Comparación entre el efecto de lactobacillus casei y el de una vacuna comercial en pollos contra la coccidiosis

This study was carried out to determine a possible protective effect of Lactobacillus casei against Eimeria spp. infection in broilers. In Stage I (SI), 165 broilers were used to isolate Eimeria spp. in commercial farms and to determine the number of oocysts to be used per bird in a challenge. In Stage II (SII), 300 broilers were distributed at random into five groups, each with three replicates (20 birds/replicate). Birds in group A were treated with a commercial vaccine, orally 15 d before the challenge (b.c.). Each bird in group B was inoculated intraperitoneally (i.p.) with viable L. casei organisms 7 d b.c. Animals in group C were inoculated i.p. with a supernatant from L. casei growth media seven d b.c. Birds in group D acted as non-treated infected control and those from group E performed as non-treated uninfected control. Protection was assessed through the anticcocidial index (Al). In SI a combination of Eimeria acervulina (125,000), E. tenella (100,000) and E. maxima (100,000) oocysts per bird was used as an inoculum in the challenge. The AI obtained in SII for groups A, B, C, D, and E was 189 (adequate), 177 (moderate), 86 (bad), 65 (bad) and 200 (good), respectively. On d 33 a.c. mean weight of broilers treated with the vaccine and of those inoculated with L. casei was similar. These results suggest that L. casei could be considered as an alternative for coccidiosis control in broilers.