Optimal broiler gut function key to performance

With the immune and nutritional function of the broiler intestine being so interrelated, producers need to achieve an optimal balance to maximize growth and performance.

Clements 90x90 Headshot Headshot
(Willee Cole)
(Willee Cole)

Successful broiler production is dependent on good intestinal quality, according to Parana Federal University’s Luis Felipe Caron, and the quality of the gut must to be taken into account from the very start of the production process in order to minimize losses.

Speaking at the Biomin World Nutrition forum, held in South Africa late last year, Caron noted that a failure to ensure that chicks have access to food during the first 48-72 hours post-hatch will lead to a loss in intestinal development, resulting in irrevocable economic loss in terms of weight gain and immune costs.

Gut development in the chick is influenced by immediate access to solid food after hatching, and by the environmental microbiota typical of the adult bird’s intestine. In adult birds, the microbiota contains, on average, 107-1,011 bacteria per gram of intestinal contents, and more than 600 bacterial species are present in the cecum.

There is a direct and constant relationship between the nutritional and immune function in the gut. For example, experimental protocols have shown that, in conventional animals with a normal intestinal flora, at least 106 bacterial cells of Salmomella enteriditis are needed to trigger illness, yet in specific pathogen-free animals, 10 cells are sufficient.

Age is among factors that affect the immune system, and intestinal immaturity may present a risk to chicks when they are exposed to antigens, for example. This has been observed in the gut’s intraepithelial T lymphocyte generation and functionality, which translates into specific immune responsiveness. There is a delay in response over the first six days, and this continues during into the first weeks, while the immune system is still maturing.

Benefits for individual birds, whole flock

The easiest way of understanding the action of intestinal health on immune response may be to consider that an intact gut does not simply result in minimal immune system use, with little investment in immune response and therefore higher metabolic gain. Rather, with better intestinal health, the chances for pathogens to invade are lower, resulting in less contact with the bird.

For individual birds, shorter contact time will be due to reduced invasion of the internal organs from the intestine, replication will be lower and damage to health minimized. The excretion of pathogens and the spread of disease will be reduced, with lower incidence and prevalence, and a therefore lower costs.

Consequently, the greatest benefits occur at flock level, as the health of each bird is improved, which also benefits the environment in which the birds are raised.

Investing in the health or immunity of the digestive system as a whole brings a gain from lower environmental pathogen pressure, in the medium or long term.

In addition to investing in intestinal integrity, broiler producers also need to pay attention to the intestinal microbiota, as this population can be used to achieve a balance that is useful for controlling challenges.

The intestinal microbiota also provides protection from infection, directly through competition for nutrients and space.

Use of feed additives affecting microbial growth can have a significant impact on the investment that a broiler may have to make to confront any field challenges.

Growing understanding

The intestinal mucosa has several mechanisms to protect the host from bacterial infection, and these include the sensing of organisms by pattern recognition receptors, induction of different interleukins, cell axis, amplification of pro-inflammatory responses, the secretion of antimicrobial proteins and the recruitment of neutrophils.

Increasing knowledge of the dynamics involved in the mucosal immune response over recent years has allowed the development of measures that can optimize broiler production, guaranteeing a sensitive balance between immune response and performance.

However, an improved understanding of the genetic and microbial differences behind these dynamics will be vital the development of new strategies to control or prevent mucosal pathogen infections, and similarly there were would be benefit in more thoroughly understanding how intestinal microbiota balance affects immune cost, and so performance.


5 ways to aid antibiotic-free broiler enteric health


Page 1 of 1580
Next Page