Enhancing pig production in the Asia-Pacific region: a nutritionist’s perspective

Pork has long been a staple food item in most Asia-Pacific countries. In fact, the Asia- Pacific region accounts for more pigs than the rest of the world combined - largely due to the massive pig population of China.

However, the dominance of numbers does not necessarily imply superior efficiency of production and a review of the pig raising activities throughout the region would reveal a broad spectrum of production systems, variable efficiency and volatile economics.

Unfortunately, herd recording is not a common practice throughout much of Asia; and those operations that keep records tend to regard them as confidential.

Two countries that conduct a national recording monitor are Australia and the Philippines; and although representing only a modest cross-section of the industry, they provide some insight into the average and range of productivity within those countries. Table 1 summarises some key performance indicators in the region and demonstrates the potential for improved productivity and efficiency.


Table 1. Selected performance indicators for Australia and Philippines.


Source: Australian Pork Ltd, 2003; Arganosa et al., 2003



The Asia-Pacific region is characterised by a diverse cross-section of ethnic groups, climatic conditions varying from tropical to cool temperate, and a disease status that ranges from specific pathogen free to full exposure. This creates a number of problems for specific enterprises in terms of community pressure, environmental responsibilities, disease risks, market access, feed ingredient supply and quality issues.

Of the five principle disciplines of pig production (genetics, health, environment, nutrition and management) consensus would rank health and environment as the prime constraints, but probably the latter two have the greatest influence on productivity and profitability, though there is often significant interaction between disciplines (e.g. nutrition x health). The prime constraints vary between regions and among individual operations within regions.

There is reasonable access to world genetic resources, except for Australia where genetic imports are prohibited due to quarantine concerns. There is access to vaccines, drugs and biosecurity measures to manage the health challenges, as well as access to housing design and engineering technology to control the environmental challenges, though not necessarily within the financial reach of all sectors of the industry.

Although there are a number of large corporate production facilities throughout Asia, the greater proportion of the industry is made up of smallholders utilizing a modest level of technology. This traditional structure is unlikely to change in the short term and hence if the industry is to advance, methods to facilitate technology transfer into this sector as well as the corporate producers need to be developed.

The Premier Pig Programme (sponsored by Alltech Inc.), developed in Australia and introduced to other parts of Asia, has made some progress in this direction. From the surveys conducted with producers as a component of this programme, feed ingredient quality and feeding management have been identified as significant areas of concern.


Feed ingredient quality

This encompasses many aspects including variations in nutrient composition, feed ingredient integrity, and physical composition of feedstuffs.


VARIABILITY OF BASIC NUTRITIONAL PARAMETERS

In an in-depth analysis of Australian feed grains, van Barneveld (1999) identified a wide range in energy, protein and amino acid availability values for cereal grains and grain legumes (Table 2).


Table 2. Range of nutritive values in feed grains.


van Barneveld, 1999



Throughout Asia, feed materials are drawn from many sources both local and imported and involve many different forms of conventional materials as well as by-products. As such, the range in nutrient content would be as wide, and probably wider than that identified in Australia. Consequently, there is a need for a rapid but reliable method of monitoring this variance to allow effective management of livestock nutrition.

Recent developments in the field of NIR spectroscopy have facilitated this by extending measurement beyond the traditional parameters of moisture, protein and fat to include pig digestible energy and poultry metabolisable energy as well as total and available amino acid content in feedstuffs (Valdez and Leeson, 1992; Jackson et al., 1996; Givens et al., 1997; van Barneveld et al., 1998).

Feed formulation becomes meaningless without accurate estimates of the nutrient composition of the feedstuffs employed.


FEED INGREDIENT INTEGRITY

Ingredient quality is a major concern, particularly in the tropical areas of Southeast Asia. The high temperatures and humidity predispose feed ingredients to extensive degradation if processing, handling or storage facilities are sub-optimal. The damage involved can take the form of:

• Protein putrefaction leading to a loss of amino acids, formation of biogenic amines and ammonia, and reduced palatability. This usually involves high moisture content from delayed processing, poor drying, or exposure to rain or condensation.

• Oxidation of fats and other vulnerable components leading to a loss of vitamin activity, reduced palatability (rancidity) and risk of spontaneous combustion. Unsaturated fats are more vulnerable to oxidation and metals such as copper and iron act as oxidative catalysts.

• Mould infestation and associated mycotoxin production, leading to acute toxicity, immunosuppression, infertility, embryo mortality, agalactia, prolapses, etc.

• Insect/rodent damage - loss of product, bacterial contamination.

Feedstuffs are perishable items and so require quick turnover or appropriate storage facilities. End users need to be proactive with regard to promoting the use of antioxidants and mould inhibitors before any deterioration rather than attempting to recover value from degraded material. Therefore not only do end users need a disciplined quality assurance protocol for receiving materials but also appropriate handling procedure, and feed hygiene strategies to prevent any further deterioration on-site.

Swamy (2005) citing surveys of feedstuffs in India and China, reported a 90+% incidence of mycotoxin contamination with up to six different mycotoxins being isolated concurrently in many samples. Given the toxicological synergy that occurs between mycotoxins, in situations where mycotoxins cannot be avoided the use of an effective mycotoxin adsorbent is almost mandatory.


PHYSICAL COMPOSITION OF FEEDSTUFFS

One of the constant challenges in many parts of Asia is achieving adequate feed intake under oppressive conditions (temperature and humidity). Complicating this is the fibrous nature of many of the by-products on offer (e.g. wheat bran, rice bran, palm kernel meal, copra, leaf meal, soya hulls, sunflower meal, cottonseed meal, kapok meal, etc) and the low biological value of alternative proteins. Since fibre fermentation and protein deamination add to the heat increment, increasing inclusion rates of these materials can result in further intake depression.

This effect can be partially offset by increasing energy density using added fat and replacing part of the protein contribution with synthetic amino acids - as long as the added fat is stable and palatable and the diets are fed at least twice/day or more frequently to ensure full utilization of the synthetic amino acids.

Feed related issues are often the root cause of production problems though commonly involving complicating interactions with the environment, health and management. Two problems common throughout Asia are piglet diarrhea and its influence on post-weaning mortality and reproductive shortfalls, particularly low litter size.


Piglet diarrhea

The problem surrounding piglet diarrhea is not a simple question of dealing with virulent pathogens. It is a complex network of factors that exert influence from the point of conception that must be dealt with in a holistic manner. Contributing factors include:


a) Gestating sow nutrition

• Poor transfer of inorganic iron (Fe) and selenium (Se) to the foetal mass resulting in weak, lighter piglets born.
• Mycotoxin interference (especially zearalenone) retarding foetal growth and reducing sow immunity.


b) Reduced colostral protection

• Inadequate colostrum intake and reduced colostrum quality,

• Need to remove any mycotoxin interference, reinforce immunocompetence with lactobacilli or mannan oligosaccharide support, and provide appropriate vaccinations or exposure to ensure broad spectrum protection.


c) Low weaning weight

• Gut maturity is a function of pig weight at weaning.

• Need to promote lactational output in the sow via elevated feed intake, and/or supplementary feeding of piglets, and/or delayed weaning age.


d) Nutritional challenge post-weaning

• It is important that pigs eat immediately post-weaning as extended delays can damage the gut (Pluske et al., 1991).

• The diet needs to be of high quality (digestible, palatable, low acid binding capacity, minimum 10% lactose, non-antigenic, supported with acids, enzymes, antibacterials, etc).

• The piglet needs immunological support (e.g., immediate immunoglobulin delivery from porcine plasma complemented with nucleotides from yeast extract (e.g. NuPro®) to promote active immunity.


e) Hygiene

• Need to minimize exposure to pathogens (biosecurity).

• Reduce sow shedding of bacteria using acids.

• Clean and disinfect facilities between batches.

• All in/all out, single age, segregated production.

• Minimise vectors (staff, equipment, birds, rodents, cats).

• Ensure clean water (quality, quantity, temperature).


When all the above points are addressed concurrently, piglet diarrhea will be minimised. Sow reproductive output

Low litter size is reported as a common problem throughout Asia and is frequently attributed to the tropical heat. Yet, individual farms can achieve respectable litter size by world standards within the same environment, which raises the possibility of mycotoxins or the feeding and physical management of the sows as potential contributing factors on individual farms.

The number of pigs born alive per litter is the culmination of a series of events from ovulation, fertilisation, implantation, embryo survival, through to stillbirth losses at farrowing. Factors which have been identified to promote success in each of these phases include:

• Supplementing organic chromium to stimulate insulin sensitivity and reinforce the hormonal signals driving ovulation.

• The use of Sel-Plex® organic selenium, vitamin E, vitamin C, and omega-3 fatty acids in boars to improve semen quality.

• Optimum timing of insemination.

• Organic zinc to promote rapid uterine involution to be in readiness to commence the next pregnancy.

• Controlled feeding in the first three weeks of pregnancy to prevent an elevated progesterone clearance from the blood and a reduced survival rate of embryos.

• Sel-Plex® organic Se and Fe which cross the placenta to nourish the developing foetal mass.

• Sel-Plex® organic Se to prevent farrowing fatigue leading to stillbirths.

• Feeding of elevated protein levels in lactation aimed at delivering 60 g lysine/day such that despite inevitable body weight loss most of it will be as fat, with protein mass being preserved. Since the latter is a prime determinant of fertility this preservation will ensure no erosion of subsequent litter size (Tritton et al., 1996).


Therefore, the aetiology of reduced litter size can be a complex interaction of health, toxins, climate, and management practices and requires a multi-disciplinary approach for successful correction. If reproductive output can be elevated via litter size and losses from piglet diarrhea and resultant post-weaning mortality can be contained, then these two things alone will go a long way to enhancing productivity.

Critical to the success of this is management and in particular staff training. When the staff have a sound understanding of the causes of specific problems and have been instructed in the standard procedures necessary to avoid them, then there is a much higher probability of success.

Although it is necessary for management to adjudicate on basic policy in the area of genetics, health strategies, environmental control, feeding strategies and production planning, probably management’s prime role is to motivate staff and provide the necessary training to allow employees to do their jobs well.

There are many new technologies now available to the Asia-Pacific pig industries that have the potential to enhance production, but there is a real risk of failure if the people at the animal interface do not have adequate understanding to ensure their effective application. Consequently, education and training emerge as the priority prerequisites to enhance pig production in the Asia- Pacific region.

Once the knowledge and skills are in place, current constraints can be identified and addressed in an orderly and coordinated manner to lift productivity to similar levels as the advanced industries in other parts of the world.


References

Arganosa, V.G., E.C. Villar, M.O. Maleon, R.M. Galamgam and A.B. Flores. 2003. Swine Production Performance in the Philippines. Philippine Swine Industry Research and Development Foundation Inc. Australian Pig Annual 2003. Australian Pork Limited.

Givens, D.I., J.L. de Boeuer and E.R. Deaville. 1977. The principles, practices and some future applications of near infrared spectroscopy for predicting the nutritive value of foods for animals and humans. Nutr. Res. Rev. 10:83-114.

Jackson, D.A., J.D. Bodin and R. Maillard. 1996. Determination of total and digestible amino acids by near infrared reflectance spectroscopy. Proc. Austr. Poult. Sci. Sym. 8:46-52.

Pluske, J.R., I.H. Williams and F.X. Aherne. 1991. Maintenance of villus height and crypt depth in the small intestine of weaned piglets. In: Manipulating Pig Production III (E.S. Batterham, ed). Australian Pig Science Association, Werribbee, Australia, p. 143.

Swamy, H.V.L.N. 2005. Mycotoxicosis in Poultry: An overview from the Asia - Pacific Region. In: Nutritional Biotechnology in the Feed and Food Industries, Proceedings of Alltech’s 21st Annual Symposium (T.P. Lyons and K.A. Jacques, eds). Nottingham University Press, UK, pp. 75-89.

Tritton, S.M., R.H. King, R.G. Campbell, A.C. Edwards and P.E. Hughes. 1996. The effect of dietary protein and energy levels of diets offered during lactation on lactational and subsequent performance in first litter sows. J. Anim. Sci. 65:573-579.

Valdez, E.V. and S. Leeson. 1992. Near infrared reflectance as a method to measure metabolisable energy in complete poultry feeds. Poult. Sci. 71:1179-1187.

Van Barneveld, R.J., J.D. Nuttall, P.C. Flynn and B.C. Osborne. 1998. NIR measurement of the digestible energy content of cereals for growing pigs. J. Near Infrared Spectr. 7:1-7.

Van Barneveld, R.J. 1999. Chemical and physical characteristics of grains related to variability in energy and amino acid availability in pigs: A review. Austr. J. Agric. Res. 50(5):667-688.