Perhaps as a farmer or feed compounder you believe that you know exactly what constitutes ‘gut health’. Yet defining gut health isn’t easy. A healthy gut must be healthy physically, chemically and immunologically. It must play host to a bacterial population that also has a favorable impact on all those parameters. And all of these factors interrelate.
Diet, disease and environmental management are just a few of the factors which can disrupt the balance of these contributory components and affect gut health. Even a subtle compromise in gut health can have severe consequences for the disease status, welfare and production performance of the animal.
Why does it matter?
A key objective for any producer is to achieve maximum production from their stock for minimum cost. Nutrition is often the major component of total costs in many production systems, so getting the most from it is critical.1Without good gut health, this is not possible, resulting in reduced feed conversion ratio (FCR) and growth rates.
Food production is becoming more competitive. The cost of animal feeds and drive to reduce antibiotic usage has increased. This means maximizing FCR has become even more important. Animals with poor gut health are also more susceptible to disease – a huge consideration for producers worried about reducing costs and maximizing production. For example, poultry with poor intestinal health are more likely to be affected by coccidiosis – one of the most costly diseases to the poultry industry.1 Producers that want to maintain a competitive edge can’t afford to ignore intestinal health.
Digestion and protection
As well as digestion of food and absorption of essential nutrients, the gastrointestinal tract has a number of other vital functions. The inner lining of the gut consists of a one-cell-thick layer called the epithelium, made up predominantly of intestinal epithelial cells (IECs). This mucosal layer provides the first line of defense against harmful agents, which is crucial, as the gut is constantly exposed to a number of potential hazards. In fact, the gut mucosa is the largest exposed surface area in the body of most animals.2 This means that there’s huge potential for breaching its barriers and explains why defense is so important. It provides protection through various physiological means, as well as by stimulating an immune response.
The structure of the mucosa is the first physical factor which contributes to the gut’s protective properties. The IECs are closely connected, joined by ‘tight junctions’ which create a seal against the contents of the gut. This way the mucosa can act as a selective barrier, enabling beneficial nutrients to be absorbed through the cells, while keeping harmful substances out. Production of a mucus lining as well as other protective substances such as glycoproteins helps to shield the cells of the mucosa and can trap harmful organisms. The IECs are continually and rapidly regenerated, which also helps to keep the gut lining healthy.