Efficacy of probiotics and medicinal plants on Eimeria tenella infection of chickens and their effect on development of immunity
Abstract
Anticoccidial efficacy of probiotics (Lactobacillus acidophilus-1 g/kg, Saccharomyces cerevisiae-1 g/kg) alone and in combination with salinomycin (60 ppm), Neem (Azadirachta indica) and Papaya (Carica papaya) against Eimeria tenella, using criteria mentioned in WAAVP Guidelines along with the effect of these agents on host immunity during the infection were studied.
A total of 108 cage reared birds randomly allocated to nine groups were used, out of which all groups except the negative control received an infection of 50,000 sporulated oocysts of Eimeria tenella per bird on 21 days of age. Lesion scoring, analysis of serum protein profile, total lipids, carotenoids, haematocrit was done on day 7 post inoculation (p.i.). On day 8 and 9 p.i., OPG counts were estimated. Serum Ig Y levels were determined using 11th day p.i. sera. DTH test was done on 14th day p.i.
All probiotic fed groups produced a significant fall in oocyst output with reduction being 79, 84, 82, and 79 % of positive control respectively for Lactobacillus acidophilus, Lactobacillus acidophilus + salinomycin, Saccharomyces cerevisiae and Saccharomyces cerevisiae + salinomycin groups. The least fall in PCV was experienced by Lactobacillus acidophilus group and the rest of the groups except yeast alone group recorded significantly lower falls compared to the positive control. Only Lactobacillus acidophilus group fared poorly in MWG and FCR whereas all other were far better than positive control and yeast groups proved even better than negative control. Only Lactobacillus acidophilus + salinomycin group recorded significantly elevated serum Ig Y levels while other groups showed insignificantly elevated levels. All probiotic fed groups showed significantly enhanced CMI responses, Saccharomyces cerevisiae + salinomycin group being the highest.
Among the medicinal plant groups Papaya group resisted the infection well with its oocyst output being the lowest (88 % reduction), significantly less fall in PCV, good weight gain and FCR. Neem group performed well with respect to parasitological parameters but failed miserably in performance parameters which may be ascribed to systemic toxicity. The combination of these two powders did not go down well with this infection as the group performed no better than the positive control. Papaya groups recorded significantly elevated serum Ig Y levels whereas Neem group had the highest CMI response.
Probiotics, Papaya and Neem certainly seemed to have anticoccidial effects with apparent immuno-modulatory mechanisms involved.