Feed Industry
The consumer is king: where will it all end for the feed industry?
Published: December 30, 2011
By: T. PEARSE LYONS - Published in 1998 (Courtesy of Alltech Inc.)
Where did this shift in focus from production to consumer issues begin for the feed industry? Perhaps it started as early as 1969 when the Swann Report hinted at a connection between antibiotic resistance and their use in food animal diets (Table 1). Perhaps it was an ill-informed junior minister in Britain commenting on salmonella in eggs. Perhaps it was the media catching Mad Cow Disease.
Whatever the reason, the consumer is now wide awake and paying full attention to our industry. ‘Healthy eating’ is on the rise. The ‘Nutraceutical’ era of ‘we are what we eat’ is upon us; with meat and the food animal industry as a whole under scrutiny.
Investigative reporting has found our defenses woefully ill-prepared for campylobacter in chickens, salmonella in eggs and pollution from farms. The accusations are coming fast and furious: 130 times more animal than human waste in the USA alone; antibiotic residues in meat; animal welfare secondary to production/economic concerns.
Table 1.A consumerism time line.
THE REALITY: THE ARRIVAL OF AN EDUCATED, OPINIONATED CONSUMER
How can the feed industry cope with a world of consumers connected to an information highway expected to contain 2 billion ‘surfers’ (almost 40% of the world population) by the end of the decade? Is it only months since a possible link between BSE and the human variant CJD hit the headlines?
Can it be only 12 months since Jacques Santer made the promise to return to natural feeding programs in Europe? Ironically, it is 17 years since a feed ingredient company called Alltech launched itself into the industry with the same mission: to provide natural alternatives for animal feed programs. Today our company numbers 450 people worldwide and the message is still the same.
There are natural alternatives to antibiotics, to mineral wastage and to pathogens in meat. But now, the message is stronger as these alternatives are backed by years of scientific research.
The solutions are also friendly to the environment, they avoid the consumer ‘no go’ areas of genetically engineered bacteria or plants and animal protein recycling. The solutions let the consumers decide what is rational and reasonable and provide them with what they require. The solutions are open, and just like the leading British feed company’s new approach, they are a documented ‘passport’ to food safety and quality.
They allow traceability of every cut of meat to feed to farm to animal without fear of surprises.
Surprises are exactly what today’s consumer does not want. This consumer is a different breed from the consumer of only 10 years ago (Table 2).
Today’s consumers are better informed, better educated, technologically competent and feel perfectly capable of making individual decisions about what is safe, healthy and desirable with respect to food.
The consuming public follows radio and television ‘talk shows’ where no topic is taboo and opinion rather than fact reign. They are asking ‘Why should agriculture be allowed to do whatever it wants? Why shouldn’t we tell agriculture what we want it to do?’
What, then, are the consumer-friendly and scientifically proven solutions available to today’s forward-thinking feed producer and animal rearer? The following is a brief insight into some of the more widely used, scientifically and practically-proven solutions and the issues they address.
Table 2. The future.
Issue: Reduce antibiotic use
Alternative: Mannanoligosaccharides – the natural carbohydrate alternative
The purpose of using sub-therapeutic or growth-promotant levels of in-feed antibiotics is to manipulate the balance of microorganisms in the gastrointestinal tract in favor of non-pathogens. The desired microbial balance can be also achieved using natural routes, in particular by providing nutrient sources which favor establishment and growth of benevolent bacteria while in effect starving pathogens.
Mannose sugar is such a nutrient; and it has an added benefit in that it confuses bacterial pathogens that would normally attach to the intestinal epithelium via mannose-bearing lectins. Receptors on bacterial cells instead bind dietary mannose and fail to attach and colonize the intestine. Attached to this figurative ‘raft’, pathogens are washed through the gastrointestinal tract without causing harm. The result is the desirable intestinal microbial population of a normal, healthy animal.
Is this approach to manipulating the gut microflora effective? This concept has been applied to animal feeds in Bio-Mos, a product comprised of modified mannanoligosaccharides. Developmental research with mannanoligosaccharide has focused on its nutritive effects on various bacteria, ability to bind pathogens with Type I fimbria (many species of E. coli and salmonella) and aid the animal’s capacity to fight disease via the non-specific or innate immune system.
Results with a wide range of species demonstrate these responses (Table 3); however, the key question is whether these responses translate to improvements in animal health and performance. Answers to this question have come from controlled studies in both research and commercial facilities showing feed efficiency improvements and lower disease incidence in a wide range of food animal species (Table 4). Mannan sugars, easily added to conventional, liquid, pelleted or extruded feeds, indeed offer a robust alternative to antibiotic reliance.
Table 3.Research into mannan sugar mode of action.
Table 4. Bio-Mos: Results of performance/health response research.
Issue: Trace mineral effectiveness, mineral excretion and pollution
Alternative: Bioplexed trace minerals
The August 8, 1997 announcement by Japan’s Ministry of Agriculture that dietary zinc and copper levels must be substantially reduced (Table 5) sent shock waves through the pig industry and sent a clear message: mineral wastage into the environment is no longer acceptable. Trace mineral level and form are at the heart of the issue.
High levels of inorganic zinc (oxide) and copper (sulfate) have long been used for their antimicrobial (and consequently growth promotant) effects in pig diets; and inorganic salts have traditionally been used in all livestock diets to meet essential trace mineral needs. Low and variable bioavailability of the oxide and sulfate mineral forms limit effectiveness and require that overages be added. High fecal trace element excretion has become an issue, especially where limited land areas are available for manure disposal.
Organically-bound, or bioplexed, trace elements are designed to be more bioavailable. The protective structure allows the bioplex to avoid interference reactions during digesta transit and provides a means of taking advantage of more absorption routes from the intestine. Mineral retention is maximized and the need to add excess minerals to the diet prevented.
Table 5.Permitted trace mineral levels in Japanese pig diets as of August 8, 1997.
Beyond bioavailability, bioplexed minerals are also more bioactive. Different routes of transport or metabolism allow the bioplexed mineral to more effectively reach its target tissue. For example, both Du et al. (1995a, b) and Harmon (see chapter this volume) have shown that Bioplex Copper significantly increased liver copper levels without any change in plasma ceruloplasmin levels.
As ceruloplasmin is the transport protein normally associated with moving actively-transported copper in plasma, absorption of the intact bioplex is indicated.
Enhancing bioactivity along with bioavailabiltity explains the responses to bioplexed minerals, especially in stressed animals when requirements for minerals to meet immune function, and productive and reproductive needs are highest (Table 6).
In vivo responses in both research and practical situations include marked improvements in fertility measurements, dramatic reductions in milk somatic cell counts and improved resistance to mastitis infection.
A recent report from the Agricultural Research Institute of Northern Ireland has shown that Bioplex Iron added to diets fed lactating sows significantly improves piglet weaning weights. When Bioplex Iron (600g) was added to the lactation ration, piglet weaning weights were 0.5 kg higher.
This suggests that the organically-complexed iron is transfered to milk in sufficient quantity to improve piglet iron status. Alternatively, the benefit of receiving iron in this form might be due to its inavailability to intestinal pathogens in the piglet.
A new and exciting application for bioplexed trace elements involves activation of key enzymes in the formation of the egg shell. Both zinc and manganese are needed in the biochemical reactions that form egg shell and shell membranes.
Eggshell 49, a product comprised of bioplexed enzyme cofactors, was formulated to help maintain shell quality during the latter weeks of lay when increases in checks and cracks rob egg profits.
In a recent study at the University of Florida (Miles, this volume), Eggshell 49 was added to diets fed Hyline layers beginning at week 50. Layers were divided into those producing either good quality or poor quality shells at study initiation. Eggshell 49 significantly increased the amount of shell deposited on the egg in the hens laying poor quality eggshells (Figure 1). These are the hens that need the most help with respect to improving egg shell quality and those with greatest responsibility for lost profits.
The message on trace element supplementation is a clear one. Excess fecal excretion is undesirable on both animal performance and environmental grounds. The alternative, bioplexed trace elements, allows us to do a better job of moving trace elements into target sites in the animal while controlling the amounts of trace elements that accumulate in soil profiles.
Figure 1.Effects of Eggshell 49 on egg shell weight in hens producing good or poor quality shells.
Table 6. Research with Bioplexes: bioavailability, health and reproductive responses.
Issue: Pollution. A beef over over pork?
Alternatives for feeds to reduce manure phosphorus, nitrogen and odor
Farmers and local authorities are at odds worldwide over efforts to impose tougher rules on pig (and other animal) waste. The shocking reality is that animals produce 130 times more waste than humans in the USA. The reality is that since each pig produces as much waste as several humans, a production unit of 2.5 million pigs (and Utah is proposing one such unit with 100,000 sows) has the potential to produce more waste each day than the cities of Los Angeles or London. These cities would have many effluent treatment systems; but do pig units? Rarely.
Clearly, this is a situation that cannot be allowed to continue. It has been described by Senator Harkin of Iowa as an ‘emerging national problem’. State after state in the US are adopting tough new antipollution laws targeted to livestock operations.
Alltech has recently set up a division to seek natural solutions that range from activated anaerobic digesters to selected butyric acid and hydrogen sulfide (rotten egg smell) utilizing bacteria. Animal production units in the future will, undoubtedly, be required to have treatment systems similar to those that deal with human wastes; and our company proposes to be at the forefront of developments in this area.
Volume and composition of waste can be affected in major ways by diet composition and nutrient design. Feeds are now being produced which address pollution with respect to the quantity of waste produced, its mineral and nitrogen (N) composition and the odor it produces (Table 7).
Table 7.Waste pollution problems and feeding solutions.
THE SOLUTION TO WASTE PHOSPHORUS: NON-GENETICALLY-MODIFIED PHYTASE
"Consumer-friendly solutions should not include genetically engineered bacteria."
Jamison, 1997
Over the last 5 years one of the successes of biotechnology has been the emergence of a genetically-modified phytase which can reduce phosphate wastage.
Unfortunately the consumer will ultimately not take kindly to this solution since it comes from a genetically-engineered microorganism. By using conventional selection techniques and a return to surface culture fermentation techniques, a naturally-occurring microorganism has been found that produces the same enzyme level.
Commercialized in a new feed enzyme called Allzyme Phytase, available phosphorus content of a layer diet was reduced by as much as 40% in studies at Michigan State University without affecting egg production, bone mineral content or egg shell quality (Table 8) (Balander and Flegal, 1997).
Table 8. Effect of dietary available phosphorus, calcium source and Allzyme Phytase on egg shell specific gravity, tibia ash content and phosphorus concentration in manure.
Balander and Flegal, 1997. abcMeans differ, P<.0.05.
DOWN ON THE FARM: ODORS EVERYWHERE THE ALTERNATIVE: MEXICO PROVIDES A NATURAL EXTRACT FROM YUCCA
Smells are often considered unavoidable with livestock rearing and to some extent have been taken for granted by the farming community.
The collision between urban sprawl and intensive agriculture no longer allows odor to be ignored; and over the past several years much has been learned about how dietary factors affect the odors coming from livestock facilities.
We now know that odor (and flies) need not be synonymous with farm presence and that much can be done to reduce and eliminate bad smells. Many wellmanaged farms are virtually free of odor and employ a natural extract from the desert-growing plant Yucca schidigera as part of an environmental program. When used at rates as low as 100 g per tonne, the impact of this plant extract on odors associated with manure can be seen within 2–3 weeks. Today, many farms display signs letting the public know they are using ‘a natural solution to odor control’.
Just as odor control is more complex than simply adding a masking agent, the effects of theYucca extract involve physiology and metabolism of microbes and animals in a variety of ways to bring about a response.
A reduction in ammonia (NH3) arising from manure occurs primarily via the effects of NH3 binding on the microenvironment of fecal bacteria in manure; however, other microbial populations can be similarly affected and a change in N metabolism can result. An improvement in the efficiency with which N is used has added performance implications beyond odor control.
For example, if NH3 can be used by rumen microbes to form microbial protein, then the energy required for the liver to detoxify is not wasted and the harmful effects of high blood urea N on reproduction are avoided. In a recent experiment dairy cattle grazing lush pasture in early lactation were given either 0 or 2 g De-Odorase daily.
A higher percentage of those given De-Odorase conceived to first service (43 vs 21%) and fewer services per conception were required (Figure 2). Similarly, N retained by the pig can be used for growth.
The effects of yucca extract on N metabolism have been investigated in a number of species; and the results have added to our understanding of how animal performance and other aspects of metabolism are improved along with atmospheric NH3 reduction (Table 9).
Other aspects of manure besides NH3 release are important when evaluating environmental impact.
Composition of manure affects its value as a fertilizer; and physical characteristics such as crust and solids formation affect the ease with which manure is pumped or spread. De-Odorase has been added directly to a variety of lagoon systems for evaluation of manure treatment effects alone.
Reduction of NH3 measured in the area is a consistent response in both dairy and pig anaerobic lagoons (Table 9). In addition, a Minnesota study found that the reduction in aerial NH3 measured near a pig manure lagoon treated with De-Odorase was associated with higher N content of manure and reduced solids formation (Johnson, 1997).
Figure 2. Effect of De-Odorase supplementation of dairy cattle fed high soluble N lush pasture on reproductive parameters (conception rates are number of cows conceiving to 1st service out of a group of 21). (Fahey et al., 1998).
Table 9.Research with De-Odorase: mode of action, ammonia control, nitrogen metabolism and animal performance.
To enlarge the image, click here
Issue: Protein wastage
Waste not, want not with Allzyme Vegpro
Protein remains the most expensive ingredient in food animal diets. It is also an ingredient that is becoming more and more scarce, particularly now that recycling animal protein to animals is not considered either consumer friendly or in the case of ruminants, safe. In addition, undigested protein excreted in manure contributes to odor problems.
Improving digestion of dietary protein makes good economic and environmental sense. Ironically, the solution to reducing feed protein waste comes from that bastion of genetic engineering, the Roslin Institute, home of the cloned lamb Dolly. Although this solution is not the result of genetic modification, one of the Institute’s senior scientists, McNab, found that a natural enzyme, a-galactosidase, could release as much as 7% more energy and 7% more amino acids when added to legume proteins fed to broilers.
Work with ‘Allzyme Vegpro’, the enzyme complement designed by Pugh at ADAS in Britain, McNab and co-workers, has continued with poultry, expanding into evaluations with other legume protein sources in broilers, layers and ducks (Table 10). Recently, work with pigs has demonstrated the potential to improve feed utilization of corn/soy diets in the grow/finish phase (Lindemann, 1997).
Table 10.Response to Vegpro in research trials.
To take full advantage of the improvement in energy and amino acid/protein digestibility gained when adding Vegpro, feed formulators should add a new ingredient to the matrix called ‘Soy + Vegpro’ with higher digestible amino acid and energy values. Reformulating to the same diet specifications provides the same animal performance with a cheaper diet – by as much as 10 to 15 US$ per ton.
Issue: Undigested fiber equals lost milk production and excess fiber waste
Solution: Fibrozyme in ruminant diets
Forage remains the cheapest raw material for beef and dairy cattle due to the rumen’s unique ability to break down cellulose. Even in the most efficient animal, however, only 50–80% of the forage is utilized (or conversely, 20–50% is wasted).
If feed intake is to be maximized and the amounts of nutrients extracted from forage are to be optimum, then it is critical that fibrolytic enzymes maintain peak activity. Because changes in rumen pH modulate growth and activity of rumen cellulolytic bacteria, there is a potential for a response from an exogenous enzyme with a pH optimum different from that of ruminal cellulases.
Fibrozyme, an enzyme protected against ruminal degradation with glycosylation techniques, works at 15 g per cow per day to maintain ruminal fiber degradation at peak efficiency. Summarized in a chapter in this volume by Howes et al., the net effect is more milk from dairy cattle fed high concentrate (low ruminal pH) diets and milk protein or an increased growth rate in beef animals (Figure 3). In vitro studies have shown that ruminal cultures supplemented with Fibrozyme have higher hexose utilization and net VFA production (Figure 4).
Issue: Myotoxin contamination
Alternative: Low inclusion toxin binder
From as early as the Salem witchhunts in the 17th century, when the toxin ergot in mold on rye bread caused hallucinations, to the present day,mycotoxins have been creating havoc in the food chain.
Today it is estimated that as much as 25% of the world’s cereals are contaminated with known mycotoxins, while a higher percentage could be contaminated with toxins as yet unidentified.
The impact on the consumer can be unexplained illness, leading to a collapse in confidence in food safety. While drying grains to 12% moisture as soon as possible and good storage practices are key to minimizing the molds which produce mycotoxins, very often the feed manufacturer must deal with reality – namely, his stored grains are contaminated with mycotoxins.
Figure 3.Effect of Fibrozyme on milk yield of Holstein cows (Howes et al., this volume).
Figure 4. Effect of Fibrozyme on in vitro dry matter disappearance, hexose utilization, and net volatile fatty acid production at 12 and 24 hours (Howes et al., this volume).
To counteract mycotoxins various grades of clays are used including zeolites, bentonites and other aluminosilicate clays. Unfortunately, clays must be used at high rates (5–10 kg per ton) and recently a bentonite source was found to be responsible for elevated levels of dioxins in chickens.
Of major concern to the producer is the impact of clays on the environment. Clays are non-digestible and pass through the animal with the feces and upon entry into the waste handling system are deposited in the lagoon, contributing to solids accumulation. Typically, the inclusion rate of bentonite or other clays needed to help alleviate the effects of aflatoxin is 0.5% or 10 lb/ton of diet.
Assuming expected animal numbers and feed consumption for a farm comprised of four 880-head finishing barns, Hansen (1994) calculated that 26,217 lbs of indigestible bentonite go through the pigs into the lagoon each year – a staggering 65.5 tons in a 5 year period (Table 11).
Table 11. The amounts of indigestible bentonite accumulating annually in a lagoon.
Over the past few years a number of scientists have evaluated a range of compounds with possible applications as mycotoxin-binding agents looking for something that binds toxins without the need to add large amounts of indigestible substances or complicated chemicals to the diet.
Few useful compounds exist; however, results of studies with a new product based upon an esterified glucomannan derived from yeast are promising.
The new product, Mycosorb, has been shown to adsorb several mycotoxins in a variety of in vitro studies (Table 12). Aflatoxin is bound at highest rates followed by zearalenone. Ochratoxin and fumonisin are also adsorbed. In practice, 0.5 kg of the nutritional binder is as effective as 4 kg of clay. In addition, the new adsorbent removes other mycotoxins not affected by clays.
Table 12. In vitro mycotoxin binding by Mycosorb: a summary of research findings.
The in vitro toxin-binding studies serve to explain much of the in vivo response to Mycosorb. Devegowda and co-workers demonstrated that Mycosorb addition to aflatoxin-contaminated broiler diets resulted in improved titers to Newcastle and IBD vaccines as well as improve growth rates (Devegowda et al., this volume).
Recent data have shown that Mycosorb added to broiler breeder diets containing myotoxin increased both egg production and immune response (Table 13, Devegowda et al., this volume) Together these studies suggest that Mycosorb’s toxin-binding activity successfully ameliorates liver damage due to aflatoxin.
Table 13.Effect of dietary supplementation of modified MOS (Mycosorb) on broiler breeders fed aflatoxin-containing diets (50 to 200 ppb).*
*Afzali and Devegowda, 1997 (unpublished). †Geometric mean values. IBD = Infectious Bursal Disease; NCD = Newcastle Disease. abMeans with a common superscript do not differ significantly.
Issue: Ionophores in the spotlight?
Yeast cultures come of age
To date, ionophores have not received the kind of scrutiny given to in-feed antibiotics fed to non-ruminants. These propionate-enhancing additives have proven excellent tools in improving the efficiency with which ruminants convert feed, particularly grain, to beef. Nevertheless, ionophores are ‘chemicals’ and on that basis alone are potentially seen in the same light as ‘residue-andresistance- producing antibiotics’. This possibility has led to examining various alternatives, including viable yeast cultures.
Ionophores are assumed to promote feed efficiency by selectively inhibiting certain Gram-positive rumen microbial populations to favor those that produce propionic acid as an end product. Increased efficiency can also be promoted via another route, that of stimulating key microbial populations.
Research with Yea-Sacc1026 viable yeast culture has shown that growth and activity of ruminal bacteria that digest fiber and those that convert lactic acid to propionic acid are promoted when this natural product is added to the diet (Figure 5).
In fact, research with yeast cultures has advanced to the point where strains of yeast can be selected to target microbial populations critical to digestion of various diets. For example, Yea-Sacc1026 is most useful when diets contain substantial amounts of both grain and forage such as dairy diets.
Yea-Sacc8417 targets balance of the populations present on very high grain diets while Yea-Sacc8417 focuses on maximizing activity of the fiberdigesting species present on an all-forage diet.
To enlarge the image, click here
Figure 5. Stimulation of specific strains of ruminal bacteria by Saccharomyces cerevisiae 1026 (Yea-Sacc1026). + signs indicate a significant (P<0.10) stimulation of the specific bacteria measured by a reduction of the lag time during growth (Girard, 1996).
Issue: Sodium selenite: Low bioavailability, high toxicity
Solution: Organic selenium in selenium yeast
Supplying selenium (Se) to livestock and poultry has been a problem for some time. Toxicity of the standard inorganic source, sodium selenite, has led to tight regulation owing to its potential hazards to humans while poor bioavailability to animals has meant that the low supplementation levels allowed are inadequate to meet needs for health and reproduction.
The different routes of absorption and metabolism of selenomethionine in Sel-Plex 50 selenium yeast have proven to increase bioavailability and overall antioxidant status in a wide range of species and research studies (Table 14).
Piglets are born with better Se reserves; and recent studies the Animal Improvement Institute in south Africa have shown both improved birth weights and reduced piglet mortality (Janyk,1998). Both calves and piglets take advantage of the increased Se in milk when the dam is given Sel-Plex 50. Better antioxidant status results in improved meat quality in both poultry and fish with longer shelf life and better fish flesh color.
A particularly useful response to the selenoproteins in Sel-Plex 50 is the marked increase in milk Se content in both sows and cows.
In a recent experiment Mahan (1998) fed six groups of seven sows diets containing either 0 added Se, 0.15 or 0.3 ppm Se from sodium selenite or Sel-Plex 50, or 0.15 ppm Se from selenite plus 0.15 ppm Se from Sel-Plex.
Within 4 days of beginning the experimental diets there was an increase in milk Se when the organic source was fed, but no increase was noted in response to inorganic Se. While increasing dietary Se from 0 to 0.3 ppm from either source increased milk Se, the increase with selenite was 44% while the increase with Sel-Plex 50 was 300% (Figure 6).
Mahan also observed that feeding the combination of inorganic and organic (0.3 ppm total) only resulted in milk Se levels similar to sows fed 0.15 ppm Se from Sel-Plex. This indicated that milk Se seems to be completely derived from the diet, not body reserves and underscores the need to provide bioavailable selenoproteins to the lactating animal – particularly when feeds are naturally low in Se.
Table 14.Responses to Sel-Plex 50 in research studies.
An added benefit for the human consumer is the fact that animals fed organic Se have higher levels of Se in meat. Perhaps there is even a message for humans in this new product.
A recent study from the prestigious medical journal Lancet showed that feeding organic Se to humans leads to a significant reduction in many forms of cancer. It would benefit both ourselves and our four-legged (for the most part) friends should our industry stop feeding inorganic Se and switch to nature’s Se source – Sel-Plex 50.
Figure 6. Effect of Se source and level on milk Se content (average of milk Se at 7 and 14 days) (Mahan, 1998).
Issue: Feeding animal-derived plasma sources to young animals
Alternative: Vegetable-based ideal protein sources
In recent years the practice of supplementing pig starter diets with plasma protein sources has become widespread owing to beneficial effects on health and early growth. Unfortunately, re-feeding animal by-products is increasingly unpopular following the BSE crisis, and the possibility of transmitting disease across either species or national borders cannot be risked.
The ideal protein concept started by Baker and Cole in the 1980s involves closely matching amino acid profiles of protein sources and amino acid requirements for a particular growth stage of the animal. Using modern knowledge of specific amino acid requirements along with enzyme technology, animal plasma proteins can be avoided. The more consumer-friendly cereal and oilseed sources can be combined and hydrolysed to form a range of ideal protein supplements; so why take the risk?
Beginning in 1998 Alltech will be manufacturing a range of supplements in a new facility inWisconsin. These supplements will be designed to meet amino acid requirements for optimum growth while allowing the producer to reduce reliance on expensive animal-based protein sources (Table 15).
Table 15.The Ultimate Protein range.
New technologies, new possibilities: Designer eggs
The arrival of the scientifically proven natural alternatives opens up new opportunities for niche markets. One example of this is the area of designer eggs.
Eggs have been described as ‘nature’s most perfect food’ owing to the high concentration and biological value of their protein for humans.
The flap over cholesterol made eggs appear less than perfect to consumers; and though the cholesterol scare has passed, it did serve the purpose of focusing research attention on how we can alter egg composition via dietary changes.
For example, it is now possible to produce eggs with specific nutritional characteristics for niche markets.
High natural iodine eggs
Iodine, important in thyroid function and overall metabolism, is deficient in modern human diets in many parts of the world. By feeding bioplexed iodine derived from selected varieties of seaweed, iodine levels in eggs can be increased tenfold.
High antioxidant eggs
Antioxidants are a key part in any functional food program. Se and Vitamin E play key roles, as do copper, manganese and zinc.
Cantor et al. (1996) demonstrated the ability to substantially increase the selenium content of eggs by supplying Se in the form of Se yeast (Sel-Plex 50) instead of the inorganic sodium selenite.
Marketing eggs based on Se content has important implications in regions where human food ingredients are lacking in adequate Se.
Omega-3 fatty acids
Altering the egg’s lipid fatty acid profile as a means of supplying omega-3 fatty acids in the human diet has received much publicity and attention in the media. Omega-3 fatty acids are needed for neural development and visual acuity in infants as well as adults.
A linear effect on omega-3 fatty acid composition in egg yolk as the concentration of flax seed or fish oil was increased in the hen’s diet was seen; and consumer acceptability of eggs from hens fed flax seed was similar to eggs from diets enriched with menhaden fish oil and not greatly different from eggs produced by hens fed standard diets (as cited by Miles, this volume).
Eggs, enriched with omega-3 fatty acids, are used as a viable alternative to the direct consumption of fish and fish by-products as a source of the omega-3 fatty acids.
Lower cholesterol in eggs: Chromium yeast and dietary mannan sugars
Reducing fat and cholesterol content of animal products seems to be the holy grail of modern nutrition these days. The cholesterol in an egg is found only in the yolk.
Eggs from commercial egg-type laying hens typically contain about 200 mg cholesterol per egg. Egg yolk cholesterol can be modified via the hen’s diet in a variety of ways.
Early work centered on changing dietary fiber as well as a number of chemical and pharmacological additives that have not reached the marketplace. Recently, experiments with both organic chromium and mannanoligosaccharides have shown a remarkable ability to reduce egg cholesterol.
Researchers in China have shown that chromium yeast reduced egg cholesterol and improved hatchability (Table 16). A study comparing chromium sources revealed that chromium yeast had the most marked effect on egg cholesterol of organic chromium sources tested (Figure 7).
Stanley et al. (1996a) demonstrated that dietary mannanoligosaccharides could reduce egg cholesterol. This information plus that available on chromium yeast has afforded commercial companies involved in the designer egg niche market a unique route to lowering egg cholesterol (Table 17).
Figure 7.Effect of organic chromium source on egg yolk cholesterol content (Cheng and Hsu, 1997).
Table 16. Effects of supplementation of Cr yeast (BioChrome) to layers.*
*Adapted from Lin and Lin, 1997.
Table 17. Combined effects of BioChrome (chromium yeast) and mannanoligosaccharides (Bio-Mos 194) on egg composition.
Do these natural additives make financial sense?
Can we afford them?
Every one of the previous issues and associated alternatives is fine in theory – but do they all make financial sense? The usual means of answering that question would be through examining the return on investment, but there is another means that is actually more comprehensive and directly applicable to the farm.
Veteran UK pig consultant, writer and commentator John Gadd believes the return to extra outlay ratio (REO) should be the pig producer’s preferred way of comparing commercial in-feed additives, supplements or nutritive ingredients.
The REO calculation determines from research trial data the amount of pig liveweight that one metric tonne of a feed is able to support. By this method, diets of different cost may be compared more realistically.Apractical example of this concept might be to look at an additive such as an antibiotic growth promoter which gives an expected REO of 3:1, but which represents 10% of the total diet cost. In other words, says Gadd, ‘good but expensive’.
When Gadd used the same REO calculation based on proven and published scientific data he showed that the natural alternatives are just as financially attractive as their inorganic or antibiotic counterparts (Table 18).
Table 18.Comparative return on extra outlay of conventional and natural feeding programs.
Whatever the reason, the consumer is now wide awake and paying full attention to our industry. ‘Healthy eating’ is on the rise. The ‘Nutraceutical’ era of ‘we are what we eat’ is upon us; with meat and the food animal industry as a whole under scrutiny.
Investigative reporting has found our defenses woefully ill-prepared for campylobacter in chickens, salmonella in eggs and pollution from farms. The accusations are coming fast and furious: 130 times more animal than human waste in the USA alone; antibiotic residues in meat; animal welfare secondary to production/economic concerns.
Table 1.A consumerism time line.
THE REALITY: THE ARRIVAL OF AN EDUCATED, OPINIONATED CONSUMER
How can the feed industry cope with a world of consumers connected to an information highway expected to contain 2 billion ‘surfers’ (almost 40% of the world population) by the end of the decade? Is it only months since a possible link between BSE and the human variant CJD hit the headlines?
Can it be only 12 months since Jacques Santer made the promise to return to natural feeding programs in Europe? Ironically, it is 17 years since a feed ingredient company called Alltech launched itself into the industry with the same mission: to provide natural alternatives for animal feed programs. Today our company numbers 450 people worldwide and the message is still the same.
There are natural alternatives to antibiotics, to mineral wastage and to pathogens in meat. But now, the message is stronger as these alternatives are backed by years of scientific research.
The solutions are also friendly to the environment, they avoid the consumer ‘no go’ areas of genetically engineered bacteria or plants and animal protein recycling. The solutions let the consumers decide what is rational and reasonable and provide them with what they require. The solutions are open, and just like the leading British feed company’s new approach, they are a documented ‘passport’ to food safety and quality.
They allow traceability of every cut of meat to feed to farm to animal without fear of surprises.
Surprises are exactly what today’s consumer does not want. This consumer is a different breed from the consumer of only 10 years ago (Table 2).
Today’s consumers are better informed, better educated, technologically competent and feel perfectly capable of making individual decisions about what is safe, healthy and desirable with respect to food.
The consuming public follows radio and television ‘talk shows’ where no topic is taboo and opinion rather than fact reign. They are asking ‘Why should agriculture be allowed to do whatever it wants? Why shouldn’t we tell agriculture what we want it to do?’
What, then, are the consumer-friendly and scientifically proven solutions available to today’s forward-thinking feed producer and animal rearer? The following is a brief insight into some of the more widely used, scientifically and practically-proven solutions and the issues they address.
Table 2. The future.
Issue: Reduce antibiotic use
Alternative: Mannanoligosaccharides – the natural carbohydrate alternative
The purpose of using sub-therapeutic or growth-promotant levels of in-feed antibiotics is to manipulate the balance of microorganisms in the gastrointestinal tract in favor of non-pathogens. The desired microbial balance can be also achieved using natural routes, in particular by providing nutrient sources which favor establishment and growth of benevolent bacteria while in effect starving pathogens.
Mannose sugar is such a nutrient; and it has an added benefit in that it confuses bacterial pathogens that would normally attach to the intestinal epithelium via mannose-bearing lectins. Receptors on bacterial cells instead bind dietary mannose and fail to attach and colonize the intestine. Attached to this figurative ‘raft’, pathogens are washed through the gastrointestinal tract without causing harm. The result is the desirable intestinal microbial population of a normal, healthy animal.
Is this approach to manipulating the gut microflora effective? This concept has been applied to animal feeds in Bio-Mos, a product comprised of modified mannanoligosaccharides. Developmental research with mannanoligosaccharide has focused on its nutritive effects on various bacteria, ability to bind pathogens with Type I fimbria (many species of E. coli and salmonella) and aid the animal’s capacity to fight disease via the non-specific or innate immune system.
Results with a wide range of species demonstrate these responses (Table 3); however, the key question is whether these responses translate to improvements in animal health and performance. Answers to this question have come from controlled studies in both research and commercial facilities showing feed efficiency improvements and lower disease incidence in a wide range of food animal species (Table 4). Mannan sugars, easily added to conventional, liquid, pelleted or extruded feeds, indeed offer a robust alternative to antibiotic reliance.
Table 3.Research into mannan sugar mode of action.
Table 4. Bio-Mos: Results of performance/health response research.
Issue: Trace mineral effectiveness, mineral excretion and pollution
Alternative: Bioplexed trace minerals
The August 8, 1997 announcement by Japan’s Ministry of Agriculture that dietary zinc and copper levels must be substantially reduced (Table 5) sent shock waves through the pig industry and sent a clear message: mineral wastage into the environment is no longer acceptable. Trace mineral level and form are at the heart of the issue.
High levels of inorganic zinc (oxide) and copper (sulfate) have long been used for their antimicrobial (and consequently growth promotant) effects in pig diets; and inorganic salts have traditionally been used in all livestock diets to meet essential trace mineral needs. Low and variable bioavailability of the oxide and sulfate mineral forms limit effectiveness and require that overages be added. High fecal trace element excretion has become an issue, especially where limited land areas are available for manure disposal.
Organically-bound, or bioplexed, trace elements are designed to be more bioavailable. The protective structure allows the bioplex to avoid interference reactions during digesta transit and provides a means of taking advantage of more absorption routes from the intestine. Mineral retention is maximized and the need to add excess minerals to the diet prevented.
Table 5.Permitted trace mineral levels in Japanese pig diets as of August 8, 1997.
Beyond bioavailability, bioplexed minerals are also more bioactive. Different routes of transport or metabolism allow the bioplexed mineral to more effectively reach its target tissue. For example, both Du et al. (1995a, b) and Harmon (see chapter this volume) have shown that Bioplex Copper significantly increased liver copper levels without any change in plasma ceruloplasmin levels.
As ceruloplasmin is the transport protein normally associated with moving actively-transported copper in plasma, absorption of the intact bioplex is indicated.
Enhancing bioactivity along with bioavailabiltity explains the responses to bioplexed minerals, especially in stressed animals when requirements for minerals to meet immune function, and productive and reproductive needs are highest (Table 6).
In vivo responses in both research and practical situations include marked improvements in fertility measurements, dramatic reductions in milk somatic cell counts and improved resistance to mastitis infection.
A recent report from the Agricultural Research Institute of Northern Ireland has shown that Bioplex Iron added to diets fed lactating sows significantly improves piglet weaning weights. When Bioplex Iron (600g) was added to the lactation ration, piglet weaning weights were 0.5 kg higher.
This suggests that the organically-complexed iron is transfered to milk in sufficient quantity to improve piglet iron status. Alternatively, the benefit of receiving iron in this form might be due to its inavailability to intestinal pathogens in the piglet.
A new and exciting application for bioplexed trace elements involves activation of key enzymes in the formation of the egg shell. Both zinc and manganese are needed in the biochemical reactions that form egg shell and shell membranes.
Eggshell 49, a product comprised of bioplexed enzyme cofactors, was formulated to help maintain shell quality during the latter weeks of lay when increases in checks and cracks rob egg profits.
In a recent study at the University of Florida (Miles, this volume), Eggshell 49 was added to diets fed Hyline layers beginning at week 50. Layers were divided into those producing either good quality or poor quality shells at study initiation. Eggshell 49 significantly increased the amount of shell deposited on the egg in the hens laying poor quality eggshells (Figure 1). These are the hens that need the most help with respect to improving egg shell quality and those with greatest responsibility for lost profits.
The message on trace element supplementation is a clear one. Excess fecal excretion is undesirable on both animal performance and environmental grounds. The alternative, bioplexed trace elements, allows us to do a better job of moving trace elements into target sites in the animal while controlling the amounts of trace elements that accumulate in soil profiles.
Figure 1.Effects of Eggshell 49 on egg shell weight in hens producing good or poor quality shells.
Table 6. Research with Bioplexes: bioavailability, health and reproductive responses.
Issue: Pollution. A beef over over pork?
Alternatives for feeds to reduce manure phosphorus, nitrogen and odor
Farmers and local authorities are at odds worldwide over efforts to impose tougher rules on pig (and other animal) waste. The shocking reality is that animals produce 130 times more waste than humans in the USA. The reality is that since each pig produces as much waste as several humans, a production unit of 2.5 million pigs (and Utah is proposing one such unit with 100,000 sows) has the potential to produce more waste each day than the cities of Los Angeles or London. These cities would have many effluent treatment systems; but do pig units? Rarely.
Clearly, this is a situation that cannot be allowed to continue. It has been described by Senator Harkin of Iowa as an ‘emerging national problem’. State after state in the US are adopting tough new antipollution laws targeted to livestock operations.
Alltech has recently set up a division to seek natural solutions that range from activated anaerobic digesters to selected butyric acid and hydrogen sulfide (rotten egg smell) utilizing bacteria. Animal production units in the future will, undoubtedly, be required to have treatment systems similar to those that deal with human wastes; and our company proposes to be at the forefront of developments in this area.
Volume and composition of waste can be affected in major ways by diet composition and nutrient design. Feeds are now being produced which address pollution with respect to the quantity of waste produced, its mineral and nitrogen (N) composition and the odor it produces (Table 7).
Table 7.Waste pollution problems and feeding solutions.
THE SOLUTION TO WASTE PHOSPHORUS: NON-GENETICALLY-MODIFIED PHYTASE
"Consumer-friendly solutions should not include genetically engineered bacteria."
Jamison, 1997
Over the last 5 years one of the successes of biotechnology has been the emergence of a genetically-modified phytase which can reduce phosphate wastage.
Unfortunately the consumer will ultimately not take kindly to this solution since it comes from a genetically-engineered microorganism. By using conventional selection techniques and a return to surface culture fermentation techniques, a naturally-occurring microorganism has been found that produces the same enzyme level.
Commercialized in a new feed enzyme called Allzyme Phytase, available phosphorus content of a layer diet was reduced by as much as 40% in studies at Michigan State University without affecting egg production, bone mineral content or egg shell quality (Table 8) (Balander and Flegal, 1997).
Table 8. Effect of dietary available phosphorus, calcium source and Allzyme Phytase on egg shell specific gravity, tibia ash content and phosphorus concentration in manure.
Balander and Flegal, 1997. abcMeans differ, P<.0.05.
DOWN ON THE FARM: ODORS EVERYWHERE THE ALTERNATIVE: MEXICO PROVIDES A NATURAL EXTRACT FROM YUCCA
Smells are often considered unavoidable with livestock rearing and to some extent have been taken for granted by the farming community.
The collision between urban sprawl and intensive agriculture no longer allows odor to be ignored; and over the past several years much has been learned about how dietary factors affect the odors coming from livestock facilities.
We now know that odor (and flies) need not be synonymous with farm presence and that much can be done to reduce and eliminate bad smells. Many wellmanaged farms are virtually free of odor and employ a natural extract from the desert-growing plant Yucca schidigera as part of an environmental program. When used at rates as low as 100 g per tonne, the impact of this plant extract on odors associated with manure can be seen within 2–3 weeks. Today, many farms display signs letting the public know they are using ‘a natural solution to odor control’.
Just as odor control is more complex than simply adding a masking agent, the effects of theYucca extract involve physiology and metabolism of microbes and animals in a variety of ways to bring about a response.
A reduction in ammonia (NH3) arising from manure occurs primarily via the effects of NH3 binding on the microenvironment of fecal bacteria in manure; however, other microbial populations can be similarly affected and a change in N metabolism can result. An improvement in the efficiency with which N is used has added performance implications beyond odor control.
For example, if NH3 can be used by rumen microbes to form microbial protein, then the energy required for the liver to detoxify is not wasted and the harmful effects of high blood urea N on reproduction are avoided. In a recent experiment dairy cattle grazing lush pasture in early lactation were given either 0 or 2 g De-Odorase daily.
A higher percentage of those given De-Odorase conceived to first service (43 vs 21%) and fewer services per conception were required (Figure 2). Similarly, N retained by the pig can be used for growth.
The effects of yucca extract on N metabolism have been investigated in a number of species; and the results have added to our understanding of how animal performance and other aspects of metabolism are improved along with atmospheric NH3 reduction (Table 9).
Other aspects of manure besides NH3 release are important when evaluating environmental impact.
Composition of manure affects its value as a fertilizer; and physical characteristics such as crust and solids formation affect the ease with which manure is pumped or spread. De-Odorase has been added directly to a variety of lagoon systems for evaluation of manure treatment effects alone.
Reduction of NH3 measured in the area is a consistent response in both dairy and pig anaerobic lagoons (Table 9). In addition, a Minnesota study found that the reduction in aerial NH3 measured near a pig manure lagoon treated with De-Odorase was associated with higher N content of manure and reduced solids formation (Johnson, 1997).
Figure 2. Effect of De-Odorase supplementation of dairy cattle fed high soluble N lush pasture on reproductive parameters (conception rates are number of cows conceiving to 1st service out of a group of 21). (Fahey et al., 1998).
Table 9.Research with De-Odorase: mode of action, ammonia control, nitrogen metabolism and animal performance.
To enlarge the image, click here
Issue: Protein wastage
Waste not, want not with Allzyme Vegpro
Protein remains the most expensive ingredient in food animal diets. It is also an ingredient that is becoming more and more scarce, particularly now that recycling animal protein to animals is not considered either consumer friendly or in the case of ruminants, safe. In addition, undigested protein excreted in manure contributes to odor problems.
Improving digestion of dietary protein makes good economic and environmental sense. Ironically, the solution to reducing feed protein waste comes from that bastion of genetic engineering, the Roslin Institute, home of the cloned lamb Dolly. Although this solution is not the result of genetic modification, one of the Institute’s senior scientists, McNab, found that a natural enzyme, a-galactosidase, could release as much as 7% more energy and 7% more amino acids when added to legume proteins fed to broilers.
Work with ‘Allzyme Vegpro’, the enzyme complement designed by Pugh at ADAS in Britain, McNab and co-workers, has continued with poultry, expanding into evaluations with other legume protein sources in broilers, layers and ducks (Table 10). Recently, work with pigs has demonstrated the potential to improve feed utilization of corn/soy diets in the grow/finish phase (Lindemann, 1997).
Table 10.Response to Vegpro in research trials.
To take full advantage of the improvement in energy and amino acid/protein digestibility gained when adding Vegpro, feed formulators should add a new ingredient to the matrix called ‘Soy + Vegpro’ with higher digestible amino acid and energy values. Reformulating to the same diet specifications provides the same animal performance with a cheaper diet – by as much as 10 to 15 US$ per ton.
Issue: Undigested fiber equals lost milk production and excess fiber waste
Solution: Fibrozyme in ruminant diets
Forage remains the cheapest raw material for beef and dairy cattle due to the rumen’s unique ability to break down cellulose. Even in the most efficient animal, however, only 50–80% of the forage is utilized (or conversely, 20–50% is wasted).
If feed intake is to be maximized and the amounts of nutrients extracted from forage are to be optimum, then it is critical that fibrolytic enzymes maintain peak activity. Because changes in rumen pH modulate growth and activity of rumen cellulolytic bacteria, there is a potential for a response from an exogenous enzyme with a pH optimum different from that of ruminal cellulases.
Fibrozyme, an enzyme protected against ruminal degradation with glycosylation techniques, works at 15 g per cow per day to maintain ruminal fiber degradation at peak efficiency. Summarized in a chapter in this volume by Howes et al., the net effect is more milk from dairy cattle fed high concentrate (low ruminal pH) diets and milk protein or an increased growth rate in beef animals (Figure 3). In vitro studies have shown that ruminal cultures supplemented with Fibrozyme have higher hexose utilization and net VFA production (Figure 4).
Issue: Myotoxin contamination
Alternative: Low inclusion toxin binder
From as early as the Salem witchhunts in the 17th century, when the toxin ergot in mold on rye bread caused hallucinations, to the present day,mycotoxins have been creating havoc in the food chain.
Today it is estimated that as much as 25% of the world’s cereals are contaminated with known mycotoxins, while a higher percentage could be contaminated with toxins as yet unidentified.
The impact on the consumer can be unexplained illness, leading to a collapse in confidence in food safety. While drying grains to 12% moisture as soon as possible and good storage practices are key to minimizing the molds which produce mycotoxins, very often the feed manufacturer must deal with reality – namely, his stored grains are contaminated with mycotoxins.
Figure 3.Effect of Fibrozyme on milk yield of Holstein cows (Howes et al., this volume).
Figure 4. Effect of Fibrozyme on in vitro dry matter disappearance, hexose utilization, and net volatile fatty acid production at 12 and 24 hours (Howes et al., this volume).
To counteract mycotoxins various grades of clays are used including zeolites, bentonites and other aluminosilicate clays. Unfortunately, clays must be used at high rates (5–10 kg per ton) and recently a bentonite source was found to be responsible for elevated levels of dioxins in chickens.
Of major concern to the producer is the impact of clays on the environment. Clays are non-digestible and pass through the animal with the feces and upon entry into the waste handling system are deposited in the lagoon, contributing to solids accumulation. Typically, the inclusion rate of bentonite or other clays needed to help alleviate the effects of aflatoxin is 0.5% or 10 lb/ton of diet.
Assuming expected animal numbers and feed consumption for a farm comprised of four 880-head finishing barns, Hansen (1994) calculated that 26,217 lbs of indigestible bentonite go through the pigs into the lagoon each year – a staggering 65.5 tons in a 5 year period (Table 11).
Table 11. The amounts of indigestible bentonite accumulating annually in a lagoon.
Over the past few years a number of scientists have evaluated a range of compounds with possible applications as mycotoxin-binding agents looking for something that binds toxins without the need to add large amounts of indigestible substances or complicated chemicals to the diet.
Few useful compounds exist; however, results of studies with a new product based upon an esterified glucomannan derived from yeast are promising.
The new product, Mycosorb, has been shown to adsorb several mycotoxins in a variety of in vitro studies (Table 12). Aflatoxin is bound at highest rates followed by zearalenone. Ochratoxin and fumonisin are also adsorbed. In practice, 0.5 kg of the nutritional binder is as effective as 4 kg of clay. In addition, the new adsorbent removes other mycotoxins not affected by clays.
Table 12. In vitro mycotoxin binding by Mycosorb: a summary of research findings.
The in vitro toxin-binding studies serve to explain much of the in vivo response to Mycosorb. Devegowda and co-workers demonstrated that Mycosorb addition to aflatoxin-contaminated broiler diets resulted in improved titers to Newcastle and IBD vaccines as well as improve growth rates (Devegowda et al., this volume).
Recent data have shown that Mycosorb added to broiler breeder diets containing myotoxin increased both egg production and immune response (Table 13, Devegowda et al., this volume) Together these studies suggest that Mycosorb’s toxin-binding activity successfully ameliorates liver damage due to aflatoxin.
Table 13.Effect of dietary supplementation of modified MOS (Mycosorb) on broiler breeders fed aflatoxin-containing diets (50 to 200 ppb).*
*Afzali and Devegowda, 1997 (unpublished). †Geometric mean values. IBD = Infectious Bursal Disease; NCD = Newcastle Disease. abMeans with a common superscript do not differ significantly.
Issue: Ionophores in the spotlight?
Yeast cultures come of age
To date, ionophores have not received the kind of scrutiny given to in-feed antibiotics fed to non-ruminants. These propionate-enhancing additives have proven excellent tools in improving the efficiency with which ruminants convert feed, particularly grain, to beef. Nevertheless, ionophores are ‘chemicals’ and on that basis alone are potentially seen in the same light as ‘residue-andresistance- producing antibiotics’. This possibility has led to examining various alternatives, including viable yeast cultures.
Ionophores are assumed to promote feed efficiency by selectively inhibiting certain Gram-positive rumen microbial populations to favor those that produce propionic acid as an end product. Increased efficiency can also be promoted via another route, that of stimulating key microbial populations.
Research with Yea-Sacc1026 viable yeast culture has shown that growth and activity of ruminal bacteria that digest fiber and those that convert lactic acid to propionic acid are promoted when this natural product is added to the diet (Figure 5).
In fact, research with yeast cultures has advanced to the point where strains of yeast can be selected to target microbial populations critical to digestion of various diets. For example, Yea-Sacc1026 is most useful when diets contain substantial amounts of both grain and forage such as dairy diets.
Yea-Sacc8417 targets balance of the populations present on very high grain diets while Yea-Sacc8417 focuses on maximizing activity of the fiberdigesting species present on an all-forage diet.
To enlarge the image, click here
Figure 5. Stimulation of specific strains of ruminal bacteria by Saccharomyces cerevisiae 1026 (Yea-Sacc1026). + signs indicate a significant (P<0.10) stimulation of the specific bacteria measured by a reduction of the lag time during growth (Girard, 1996).
Issue: Sodium selenite: Low bioavailability, high toxicity
Solution: Organic selenium in selenium yeast
Supplying selenium (Se) to livestock and poultry has been a problem for some time. Toxicity of the standard inorganic source, sodium selenite, has led to tight regulation owing to its potential hazards to humans while poor bioavailability to animals has meant that the low supplementation levels allowed are inadequate to meet needs for health and reproduction.
The different routes of absorption and metabolism of selenomethionine in Sel-Plex 50 selenium yeast have proven to increase bioavailability and overall antioxidant status in a wide range of species and research studies (Table 14).
Piglets are born with better Se reserves; and recent studies the Animal Improvement Institute in south Africa have shown both improved birth weights and reduced piglet mortality (Janyk,1998). Both calves and piglets take advantage of the increased Se in milk when the dam is given Sel-Plex 50. Better antioxidant status results in improved meat quality in both poultry and fish with longer shelf life and better fish flesh color.
A particularly useful response to the selenoproteins in Sel-Plex 50 is the marked increase in milk Se content in both sows and cows.
In a recent experiment Mahan (1998) fed six groups of seven sows diets containing either 0 added Se, 0.15 or 0.3 ppm Se from sodium selenite or Sel-Plex 50, or 0.15 ppm Se from selenite plus 0.15 ppm Se from Sel-Plex.
Within 4 days of beginning the experimental diets there was an increase in milk Se when the organic source was fed, but no increase was noted in response to inorganic Se. While increasing dietary Se from 0 to 0.3 ppm from either source increased milk Se, the increase with selenite was 44% while the increase with Sel-Plex 50 was 300% (Figure 6).
Mahan also observed that feeding the combination of inorganic and organic (0.3 ppm total) only resulted in milk Se levels similar to sows fed 0.15 ppm Se from Sel-Plex. This indicated that milk Se seems to be completely derived from the diet, not body reserves and underscores the need to provide bioavailable selenoproteins to the lactating animal – particularly when feeds are naturally low in Se.
Table 14.Responses to Sel-Plex 50 in research studies.
An added benefit for the human consumer is the fact that animals fed organic Se have higher levels of Se in meat. Perhaps there is even a message for humans in this new product.
A recent study from the prestigious medical journal Lancet showed that feeding organic Se to humans leads to a significant reduction in many forms of cancer. It would benefit both ourselves and our four-legged (for the most part) friends should our industry stop feeding inorganic Se and switch to nature’s Se source – Sel-Plex 50.
Figure 6. Effect of Se source and level on milk Se content (average of milk Se at 7 and 14 days) (Mahan, 1998).
Issue: Feeding animal-derived plasma sources to young animals
Alternative: Vegetable-based ideal protein sources
In recent years the practice of supplementing pig starter diets with plasma protein sources has become widespread owing to beneficial effects on health and early growth. Unfortunately, re-feeding animal by-products is increasingly unpopular following the BSE crisis, and the possibility of transmitting disease across either species or national borders cannot be risked.
The ideal protein concept started by Baker and Cole in the 1980s involves closely matching amino acid profiles of protein sources and amino acid requirements for a particular growth stage of the animal. Using modern knowledge of specific amino acid requirements along with enzyme technology, animal plasma proteins can be avoided. The more consumer-friendly cereal and oilseed sources can be combined and hydrolysed to form a range of ideal protein supplements; so why take the risk?
Beginning in 1998 Alltech will be manufacturing a range of supplements in a new facility inWisconsin. These supplements will be designed to meet amino acid requirements for optimum growth while allowing the producer to reduce reliance on expensive animal-based protein sources (Table 15).
Table 15.The Ultimate Protein range.
New technologies, new possibilities: Designer eggs
The arrival of the scientifically proven natural alternatives opens up new opportunities for niche markets. One example of this is the area of designer eggs.
Eggs have been described as ‘nature’s most perfect food’ owing to the high concentration and biological value of their protein for humans.
The flap over cholesterol made eggs appear less than perfect to consumers; and though the cholesterol scare has passed, it did serve the purpose of focusing research attention on how we can alter egg composition via dietary changes.
For example, it is now possible to produce eggs with specific nutritional characteristics for niche markets.
High natural iodine eggs
Iodine, important in thyroid function and overall metabolism, is deficient in modern human diets in many parts of the world. By feeding bioplexed iodine derived from selected varieties of seaweed, iodine levels in eggs can be increased tenfold.
High antioxidant eggs
Antioxidants are a key part in any functional food program. Se and Vitamin E play key roles, as do copper, manganese and zinc.
Cantor et al. (1996) demonstrated the ability to substantially increase the selenium content of eggs by supplying Se in the form of Se yeast (Sel-Plex 50) instead of the inorganic sodium selenite.
Marketing eggs based on Se content has important implications in regions where human food ingredients are lacking in adequate Se.
Omega-3 fatty acids
Altering the egg’s lipid fatty acid profile as a means of supplying omega-3 fatty acids in the human diet has received much publicity and attention in the media. Omega-3 fatty acids are needed for neural development and visual acuity in infants as well as adults.
A linear effect on omega-3 fatty acid composition in egg yolk as the concentration of flax seed or fish oil was increased in the hen’s diet was seen; and consumer acceptability of eggs from hens fed flax seed was similar to eggs from diets enriched with menhaden fish oil and not greatly different from eggs produced by hens fed standard diets (as cited by Miles, this volume).
Eggs, enriched with omega-3 fatty acids, are used as a viable alternative to the direct consumption of fish and fish by-products as a source of the omega-3 fatty acids.
Lower cholesterol in eggs: Chromium yeast and dietary mannan sugars
Reducing fat and cholesterol content of animal products seems to be the holy grail of modern nutrition these days. The cholesterol in an egg is found only in the yolk.
Eggs from commercial egg-type laying hens typically contain about 200 mg cholesterol per egg. Egg yolk cholesterol can be modified via the hen’s diet in a variety of ways.
Early work centered on changing dietary fiber as well as a number of chemical and pharmacological additives that have not reached the marketplace. Recently, experiments with both organic chromium and mannanoligosaccharides have shown a remarkable ability to reduce egg cholesterol.
Researchers in China have shown that chromium yeast reduced egg cholesterol and improved hatchability (Table 16). A study comparing chromium sources revealed that chromium yeast had the most marked effect on egg cholesterol of organic chromium sources tested (Figure 7).
Stanley et al. (1996a) demonstrated that dietary mannanoligosaccharides could reduce egg cholesterol. This information plus that available on chromium yeast has afforded commercial companies involved in the designer egg niche market a unique route to lowering egg cholesterol (Table 17).
Figure 7.Effect of organic chromium source on egg yolk cholesterol content (Cheng and Hsu, 1997).
Table 16. Effects of supplementation of Cr yeast (BioChrome) to layers.*
*Adapted from Lin and Lin, 1997.
Table 17. Combined effects of BioChrome (chromium yeast) and mannanoligosaccharides (Bio-Mos 194) on egg composition.
Do these natural additives make financial sense?
Can we afford them?
Every one of the previous issues and associated alternatives is fine in theory – but do they all make financial sense? The usual means of answering that question would be through examining the return on investment, but there is another means that is actually more comprehensive and directly applicable to the farm.
Veteran UK pig consultant, writer and commentator John Gadd believes the return to extra outlay ratio (REO) should be the pig producer’s preferred way of comparing commercial in-feed additives, supplements or nutritive ingredients.
The REO calculation determines from research trial data the amount of pig liveweight that one metric tonne of a feed is able to support. By this method, diets of different cost may be compared more realistically.Apractical example of this concept might be to look at an additive such as an antibiotic growth promoter which gives an expected REO of 3:1, but which represents 10% of the total diet cost. In other words, says Gadd, ‘good but expensive’.
When Gadd used the same REO calculation based on proven and published scientific data he showed that the natural alternatives are just as financially attractive as their inorganic or antibiotic counterparts (Table 18).
Table 18.Comparative return on extra outlay of conventional and natural feeding programs.
| Conclusions In the past, farmers were favorably viewed by the community. However, they receive little sympathy today following the BSE crisis; and worldwide they are on the receiving end of bad press. Animal producers are perceived in many quarters as being more concerned with profit than the welfare of animals or the environment at large. While we know that this is not the case, the media still prefers to portray the farmer as the agricultural equivalent of the Victorian workhouse owner. A change of image is desparately needed. Today’s consumer is more demanding and more educated than in the past. The feed industry, to survive against growing consumer activism and increased regulation should, in the opinion of the author, adopt the attitude that the customer is right, and provide what that customer wants: natural, environmentally friendly animal products. The impact of the consumer backlash is perhaps best summarized by the statement from the UK Minister of Agriculture who said that agriculture is now viewed just like an industry such as steel or coal and can no longer expect ‘special treatment’ from government. He was quoted as saying that ‘...despite £2 billion handed out to Britain’s beef farmers, they are still struggling and one has to question the wisdom of spending further monies in this area.’ The agricultural playing field is being altered dramatically all around the world. Agriculture in the future will no longer be singled out and future policies will reflect this new, highly competitive environment. The arrival of natural biotechnology with its innovative solutions and viable alternatives could not be more timely. The prize is there: greater market share for your feed company or farming enterprise. The rules are set, dealing openly with the public is required. The tools are in place, natural alternatives. The only question remaining is whether we have the champions prepared to adapt quickly and decisively to the inevitable. As ever, they will be the winners. |
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26 de octubre de 2017
Are really consumer friendly animal productive food entering into the market , each and every person need immediate response without discard or deductions but to sell everything to earn money never bothered about quality of food what they are eating
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