Nutrition and gut health are closely related in commercial poultry production. Diet formulation and feed management can have a marked effect on gut health, greatly influencing nutrient utilization and growth of the animal. Gut health problems arise due to improper nutrition and an unhygienic environment, especially during the early stages of chick development. For cost effective and sustainable commercial operations, there is need to: 1) Maintain natural gut health through proper nutrition and a clean environment; and, 2) effectively treat any existing gut disorder.
Intestinal integrity may be described as the intactness of the intestine in maintaining its structure and function or simply an unimpaired and sound intestine.
A sound gut ensures:
- Proper digestion and absorption of valuable feed nutrients
- Less wastage of nutrients
- Minimum foul odor
- Resistance against entero-pathogens
- Lower likelihood of mortality and morbidity losses
- Optimal feed conversion ratio
Natural physical barriers
Physical barriers protect against the entry of foreign materials and organisms into the bloodstream and access to other viscera, thus helping intestinal integrity. On occasion, due to improper nutrition or an unhygienic environment, when the load of foreign invaders increases, these barriers are breached.
There are several factors which can influence gut integrity. These include impacts by disease or toxins to compromise physical barriers as well as stress factors, feed toxins and toxicants, dietary factors such as nutritional deficiencies, health status, gut micro flora balance and beak deformity which may prevent proper feed consumption.
Early chick nutrition
A good start is an important factor in maximizing profits from broiler operations. Early nutrition mainly in the first seven days of life for broilers may program the birds' systems and set a pattern for growth and productivity. A large percentage of early growth (2 to 5 times the growth rate of other tissues) occurs in the digestive tract and those organs involved in digestion. If digestive growth is retarded during this time period, overall growth rate may be compromised. Further, newly hatched chicks are more prone to gut infections as their natural defense is yet to be strengthened, so proper care should be taken during this time period.
Delayed access to nutrients post hatch reduces the relative weight of bursa and spleen. The passage of feed that is not sterile, through the gastro-intestinal tract exposes the bursa to a variety of antigens. So the earlier the chicks are fed post hatch, the sooner will the proliferation stem cell meet environmental antigens. Suitable feed additives should be added in the starter diet as precautionary measure that will ensure better health and productivity.
Supplementation of quality feed ingredients helps in maintaining natural gut health. Many incriminating factors of feed are destroyed due to processing. Extrusion is effective in reducing microbial contamination in feedstuffs and in Salmonella control. Pelleting provides scope for utilization of high-fiber feed resources. Use of steam-pelleted feed seems to be of value in maintaining gut health.
Commercial poultry production during the last 50 years has benefited from pharmaceutical and biological products that enabled flock size to increase, genetic potential and improved nutritional formulations to be realized, and overall production to increase. Essentially, there are two main ways in which we can reduce our dependence on antibiotic use in animals. An obvious choice is the development of alternatives to antibiotics that work via similar mechanisms, promoting growth while enhancing the efficiency of feed conversion. A more difficult route would be to improve animal health.
Regardless of the level of hygiene and biosecurity imposed at production level, poultry will be exposed to multiple infections and toxic agents through the feed and environment.
Today's intensive animal agriculture industry must adapt to producing animals in a world without antibiotic growth promoters. Although no single alternative may be as effective as antibiotics, a combination of strategies and feed additives can be used to achieve good gut health and growth performance. Nutrients are intended, after all, to be taken up and used by the host animal, rather than by the resident bacteria.