The effect of a probiotic preparation containing Enterococcus faecium DSM 7134 for chickens on growth performance, immune status, and the histology and microbiological profile of the jejunum

The aim of the study was to determine whether and in what dosage and duration of administration a probiotic containing live cultures of Enterococcus faecium, enriched with vitamin D3 and ascorbic acid, affects the histological and microbiological profile of the intestine, as well as the immunity and growth performance of chickens. The jejunum together with its contents was also collected for microbiological and histological testing. The results obtained indicate that the birds receiving the probiotic preparation in the amount of 0.25 g/L of water during the entire fattening period attained significantly higher bodyweight than the Control, with significantly lower feed conversion. Furthermore, this dosage and duration was most efficient in reducing the total count of fungi, aerobic bacteria and coliform bacteria in the intestinal contents, in addition to increasing the height of the jejunal villi and depth of the crypts. The probiotic administered in the amount of 0.25 g/L of water during the entire fattening period also significantly increased lysozyme activity and the content of IgA in the blood serum as compared with the Control, while decreasing the content of IL-6, and thus most efficiently stimulated non-specific immunity in the chickens.