Effect of direct-fed microbials on growth performance, blood biochemical indices, and immune status of female goats

The effect of direct-feed microbial (DFM) treatment on body weight, serum biochemical indexes, serum immunoglobulins, and serum cytokines was studied. The study was a completely randomized design with 20 growing females Beichuan white goats, weighing 25.11 ± 1.96 kg, divided into two groups of 10 goats per treatment. Goats were offered (1) 10 mL saline solution (Control group) (2) or 10 mL microbials solution (DFM group) on days 0 and 7 for two times. No effect on final body weight and body size was observed between DFM and control group (p > 0.05). DFM treatment had greater serum total protein, globulin, and albumin/globulin ratio than the control treatment (p < 0.05). The concentrations of IgA, IgG, IgM, INF-γ, and IL-2 in DFM group were significantly higher than those in the control group on days 7, 14, and 21 (p < 0.05), and the highest content was detected on day 14 of the experiment. The concentrations of IgA, IgG, IgM, IL-2, INF-γ, INF-α, IL-4, and IL-5 in DFM group on day 14 were higher than those on day 0 (p < 0.05). In conclusion, DFM enhanced serum immunoglobulins and cytokines without affecting body weight, body size, and normal serum metabolism.