Introduction
The modern poultry industry aims at high production and better quality at a low cost. This, in addition to an increase in the demand for poultry meat, necessitates constant, efficient and goal-oriented healthcare to prevent the development of diseases.
In the future several challenges and problems, in addition to the ones already existing, will face everybody involved in the poultry production chain. These will include: strong global competition; changes in social, political and consumer perceptions in regard to food safety and animal welfare; increase of environmental protection issues; a steady increase in the cost of feed; the emergence of new and unforeseen diseases, and new legislation that will serve to regulate the related issues. The present paper describes the main challenges face the poultry production.
Strong global competition
Strong global competition and varying production costs in various regions will lead to an increase in the global movement of poultry and poultry products. This, however, increases the risk of introducing diseases to areas that are now considered to be free from such diseases. Poultry diseases will remain a major challenge to the industry. Once an outbreak of a given disease occurs, it can explode into an epidemic and may have a significant negative effect on trade in a specific country, a continent or even globally.
The steady increase in the cost of feed will accelerate the global trade. In addition, the increase of biofuel and biogas production will reduce the available land for food grains and feed production, leading to a considerable increase of feed costs for animal production. In the future, the feed industry, however, will also be forced to take more responsibility not only for the quality of the feed ingredients, but also to ensure that no poultry pathogens and unwanted contaminants and residues are present in the feed. In addition, climatic changes and limited water resources also need to be seriously considered, as they will have an influence on the cost of production.
Changes in social, political, and consumer perceptions
- Food safety
The loss of the consumers trust and confidence in the quality and safety of poultry meat is a further challenge. Poultry meat can harbour different food borne pathogens. Many reports from recent years have shown that different Salmonella serovars and Campylobacter spp. are the most common causes of human food borne bacterial diseases linked to poultry. In addition, the development of antibiotic resistance in bacteria, which is common in both animals and humans, is also an emerging public health hazard. Controlling these food borne organisms requires a broader understanding of how microbial pathogens enter and move through the food chain, as well as the conditions that promote or inhibit growth for each type of organism.
A further problem related to food safety is Campylobacter, which is the leading cause of zoonotic enteric infections worldwide. Campylobacter infections in humans are mainly transmitted by contaminated food. No evidence has been found either for vertical transmission or for horizontal transmission from one flock to the next via persistent house-contamination. However, since the organism has been detected in the intestines of most slaughtered poultry, the major route for campylobacter contamination of poultry appears to be the horizontal transmission from the environment. Investigations indicated that the external campylobacter load per chicken is increasing during transport, de-feathering and evisceration, and decreasing at the other processing steps studied, with an overall reduction of the mean load from production-to-consumption of about 4 to 5 logs. Good hygienic practice protocols should be prepared and strictly followed in all stages of production. Biosecurity should be improved throughout the production chain. Since campylobacter is found in the environment, hygienic barriers should be constructed to keep them outside the house.
Changes in social, political and consumer perceptions
- Antibiotic resistant and associated problems
The development of antibiotic resistance in bacteria, which is common in both, animals and humans, is and will also be a continuous public health hazard. It is generally known, that supplementation of poultry feed with antibiotic growth promoters (AGPs) improves performance of livestock. The effect of AGP on gut flora results in improvement of digestion, better absorption of nutrients, and a more stable balance in the microbial population. As consequence the prevalence and severity of intestinal disorders are reduced. However, AGPs also can increase the prevalence of drug-resistant bacteria. Based on „Precautionary Principle” and experiences made in some European countries, the EU completely banned the use growth-promoting antibiotics in feed of food producing animals by January 2006. Field observations in Europe showed that the poultry industry faced several problems after the ban of AGPs. The impact of the ban has been seen on the performances (body weight and feed conversion rate) as well as on the rearing husbandry (wet litter and ammonia level), animal welfare problem (foot pad dermatitis) and general health issues on the birds (enteric disorders due to dysbacteriosis and clostridial infections.
Changes in social, political and consumer perceptions
– Animal welfare
Currently, there is great concern that serious animal welfare and health problems might have been caused already due to genetic selection practices within the poultry industry. Fact is that genetic selection practices within the poultry industry have achieved significant progress in terms of growth rate, better feed conversion, better meat yield and low production cost. All the time this was accompanied by continuous improvement in husbandry practices, nutrition, and disease control. The most outstanding and visible changes in modern poultry compared to their ancestors is the rapid growth and the higher percentage of breast muscle. As a consequence it is important to understand the relationship between genetic selection pressures and other factors that may have a subsequent impact on the health conditions.
According to a published report on a new Animal Health Strategy for the European Union (2007 - 2013), the concept of animal health covers not only the absence of disease in animals, but also the relationship between the health of animals and their welfare. It will also take into account social, economic and ethical considerations, as well as support the achievement of a high level of environmental protection.
Emergence and Re-emergence of poultry diseases
Health disorders and infectious diseases of poultry are mostly associated with severe economic losses. Several pathogens are incriminated as possible causes of many disease complexes of poultry poults either alone (mono-causal) or in synergy with different other micro-organisms (multi-causal) or accompanied by noninfectious factors. Non Infectious means all factors which influence the bird health and include house structure, climatic conditions (ventilation, temperature, and litter condition), stocking density, feed and water supply, hygienic condition as well as the knowledge and qualification of the stockman. These factors affect each other and can promote or inhibit the health condition of the flock. In aim to achieve desired performance results, managers of poultry flocks should integrate good environment, husbandry, nutrition and disease control programs. The rearing management must be directed to satisfy the bird’s requirements, to promote the production and to prevent diseases condition. Any disturbance will cause stress, which will reduce the resistance of the birds, increase their susceptibility to infections and reduce their immune-response to vaccines. Infectious diseases caused by several infectious agents such as viruses, bacteria, fungus and parasites are involved in many disease conditions. These infectious agents can be introduced and spread in poultry farms by different routes. It occurs by vertical and/or horizontal route. At early days of age the main disease problems are related to vertically transmitted infections and improper hatchery eggs sanitation (Yolk sac infection/ Omphalitis) with salmonella, E. coli, mycoplasma, aspergillus, staphylococci, streptococci, pseudomonas and avian encephalomyelitis, inclusion body hepatitis. Those and other infectious agents can also be transmitted horizontally (laterally) by direct contact between infected and non-infected birds. Currently, the most important problems of poultry are respiratory diseases, possibly caused by avian influenza, Newcastle disease, infectious bronchitis, avian metapneumovirus and /or ornithobacterium rhinotracheale and E. coli. Furthermore, enteric disorders caused by several viral agents such as coronavirus, astrovirus, and rotavirus or due to parasitic infestation such as coccidia are common problems.
The severity of clinical signs, duration of the disease and mortality are extremely variable and are influenced by kind, virulence and pathogenicity of the infectious agent as well as by many environmental factors such as poor management, inadequate ventilation, high stocking density, poor litter conditions, poor hygiene, high ammonia level, concurrent diseases and the type of secondary infection. Future expectations Disease diagnosis, treatment and control In future improvements in laboratory diagnosis, such as diagnostic micro array and other technologies, will allow faster, more sensitive and more accurate diagnosis of infectious diseases, and early interventions will become a reality. However, only a few authorised pharmaceutical veterinary products will be available for the treatment of poultry as food producing animals. Future scientific findings on the pathogenic mechanisms of bacteria will help to improve the treatment of bacterial infections, and instead of non-specific antibiotic therapy, new drugs will be able to target the signalling mechanisms, which are able to disrupt the pathogenic effects of the pathogen bacteria. Vaccination is regarded as one of the most beneficial biopharmaceutical interventions due to its ability to induce protection against infectious diseases through targeted activation of the immune system. Many valuable new vaccine production technologies have been developed as a result of rapid progress in various areas. The use of future progressive vaccine production technologies, such as recombinant, subunit, reverse genetic and nucleic acid vaccines, can significantly reduce the cost of vaccines, ensure better efficacy, and allow easy and rapid intervention to face the steady mutation of the microorganisms. Furthermore, the development of efficient vaccines against bacterial infections will lead to a reduction of the use of antibiotics and subsequently of the development of resistant bacteria. Genetic resistance and selective breeding to improve production traits and health is a long-standing goal of the industry. The desire to enhance breeding strategies through the use of molecular techniques (genetic linkage maps) will lead to the characterisation of genome structure and genes that are associated with production traits and disease susceptibility and resistance. This will allow selecting bird lines that are genetically resistant to several pathogens. In addition, improvement of rearing technology, management and nutrition will help to maintain bird comfort.
Conclusions
In the future, the global cooperation and trade will force the governments to harmonize the existing different legislations related to trade, animal disease control, animal nutrition as well as the licensing of drugs and vaccines for veterinary use.
Last but not least the consumer expectations for high standards quality of poultry products will strongly influence the production methods. This means that farmers, veterinarians, stockholders and all other partners involved in the production chain will have to share more responsibilities and that cooperation will be intensified.
This paper was presented at the International Seminar AMEVEA, 2013.