摘要 : Comparative biological response of combination of different strains of lactobacilli, streptococci and yeast, isolated from different indigenous sources was studied in commercial laying chickens. The treatments consisted of T<sub>1... 展开 Comparative biological response of combination of different strains of lactobacilli, streptococci and yeast, isolated from different indigenous sources was studied in commercial laying chickens. The treatments consisted of T₁ (control feed with culture medium only), T₂ (<i>Lactobacillus bulgaricus</i> L₄+<i>Streptococcus lactis</i> S₁+<i>Saccharomyces cerevisiae</i> Y₃), T₃ (<i>L. acidophilous</i> leopard excreta+<i>S. faecalis</i> leopard excreta+<i>Torulopsis spherica</i> calf dung), T₄ (<i>L. acidophilous</i> bottle gourd+<i>S. uberis</i> bitter gourd+<i>S. cerevisiae</i> bitter gourd), T₅ (<i>L. lactis</i> tomato+<i>S. faecium</i> khamir+<i>Pichia memberanaefaciens</i> tomato), T₆ (T₂+T₃) and T₇ (T₃+T₄). In overall, the FCR was higher in probiotic fed groups as compared to that of the control. Mortality was observed in the control (T₁) and T₅ group only. Feed consumed per kg egg mass was lower and, per cent hen day egg production was higher in all the probiotic fed groups. The probiotic feeding resulted in larger egg size production. The better egg laying performance could be due to the higher total and % Gram+ve microbial counts in the intestinal tract. It could be concluded that the probiotics, fed only up to 8 weeks of age showed a carry-over effect on the laying performance throughout the laying period and there was no need to mix too many strains of microbes from different sources to increase the farm returns. 收起