Probiotics will play an increasingly important role in the feeds of the future, according to Denise Kelly of the Rowett Institute, Aberdeen.

The bacterial population of the digestive system, or microbiota, played a vital role in maintaining the health of a bird or animal and achieving good growth and feed efficiency, she told the conference. It was therefore essential to get this properly established in the early stages, and probiotics could help to do this.

A probiotic is a live micro-organism that has a beneficial effect on the host animal, and is one of three classes of “bugs” that could inhabit the gastro-intestinal tract, she explained. The other two were commensals and pathogens, and together all three formed the microbiota.

“Commensals are the naturally colonising bacteria – the good guys,” said Prof Kelly.

 

Bright future

 

Producers always had a major interest in diet form and composition, because they were trying to promote gut function as much as possible in terms of extraction of nutrients.

“However, as much as diet is impacting on the gut, the microbiota, I would argue, has an even greater impact. The future is really important and actually very bright for probiotics or live biotherapeutics.”

The microbiota of a healthy animal was highly diverse and very functional, she added. Although nutrients had a direct impact on growth rates, many of these substrates also had a bearing on the microbiota, affecting its composition and functionality.

“We are talking about trillions of organisms, and this diversity is really important to health. In humans, there are 10 times more bugs in us than human cells; equivalent to 100 times more genes.”

The two most important things micro-organisms did was to affect metabolism, and hence the growth of an animal, and the ecology of the gut.

“If you take a germ-free animal, it has no immune system. The key to unlocking the immune system is bugs. At birth or hatching, the gut has to be seeded. You get microbiological colonisation and succession.

“In early life there is a real period of instability, whether in infants, pigs or poultry. There’s lots of bugs in there trying to find a niche, with a lot of competition. As the animal matures, the microbiota becomes more stable.”

The key fact was that once the stability was formed, it was very hard to alter. So it was essential to get the microbiota right in early life.