Probiotics and lamb performance: A review

Abstract

Probiotics are naturally occurring microbes, which upon administration improve the health status of the animal by competing with the pathogenic microbes and nutrient utilization by having a positive influence on gut microflora. Addition of probiotics in the lamb’s diet has been reported to improve feed utilization and growth performance of the animals. The exact mechanism through which they affect the animal performance is not well known. However, it is stated that they work synergistically with the ruminal microbes. They also increase the ruminal pH, which favours the growth of cellulolytic bacteria. Improvement in the colonization of cellulolytic bacteria may result in improved digestion process and nitrogen flow towards lower digestive tract. Furthermore, their anti-pathogenic activity may reduce the stress on animal. Because of higher profit margin in intensive small ruminant production, farmers are shifting from tradition to high input feeding systems. In order to harvest, real benefits from small ruminants which are raised on nutrient rich diet, feed additives like probiotics are used to enhance the efficiency of nutrient utilization in growing ruminants. However, reports regarding the effect of probiotics administration on growing and fattening performance and carcass characteristics of the lambs are inconsistent. This might be related to the type and level of probiotics used and ingredient composition of the experimental diet. Thus, further research to understand the interaction of direct fed microbials with ruminal microbes is to have better understanding about adequate dose level at particular stage of lamb growth. This short review article is an attempt to recapitulate the effects of feeding probiotics on different aspects of lamb production which directly or indirectly influence the productivity and hence profitability associated with this enterprise. Key words: Probiotics, lambs performance, microbial growth.