Assessment of probiotics supplementation via feed or water on the growth performance, intestinal morphology and microflora of chickens after experimental infection with Eimeria acervulina, Eimeria maxima and Eimeria tenella

In this study, the effect of probiotic supplementation via drinking water or feed on the performance of broiler chickens experimentally infected with sporulated oocysts of Eimeria acervulina (5 x 10(4)), Eimeria maxima and Eimeria tenella (2 x 10(4) each one) at 14 days of age was evaluated. Two hundred and forty 1-day-old Ross 308 male chicks were separated into eight equal groups with three replicates. Two of the groups, one infected with mixed Eimeria oocysts and the other not, were given a basal diet and served as controls. The remaining groups were also challenged with mixed Eimeria species and received the basal diet and either water supplemented with probiotic (three groups) or probiotic via feed (two groups); the probiotic used consisted of Enterococcus faecium #589, Bifidobacterium animalis #503 and Lactobacillus salivarius #505 at a ratio of 6:3:1. Probiotic supplementation was applied either via drinking water in different inclusion rates (groups W1, W2 and W3) or via feed using uncoated (group FN) or coated strains (group FC). The last group was given the basal diet supplemented with the anticoccidial lasalocid at 75 mg/kg. Each experimental group was given the corresponding diet or drinking water from day 1 to day 42 of age. Throughout the experimental period of 42 days, body weight and feed intake were recorded weekly and feed conversion ratios were calculated. Seven days after infection, the infected control group presented the lowest weight gain values, while probiotics supplied via feed supported growth to a comparable level with that of the lasalocid group. Probiotic groups presented lesion score values and oocyst numbers that were lower than in control infected birds but higher than in the lasalocid group. In the duodenum, jejunum and ileum, the highest villous height values were presented by probiotic groups. In conclusion, a mixture of probiotic substances gave considerable improvement in both growth performance and intestinal health in comparison with infected control birds and fairly similar improvement to an approved anticoccidial during a mixed Eimeria infection.