Effect of oral administration of Propionibacterium acnes on growth performance, DTH response and anti-OVA titers in goat kids

Immunostimulants are susbstances that stimuli the response of effector cells to activate the immune response such as antigen uptake, cytokine release or antibody response. These substances can increase resistence to infection by different types of microorganisms, reducing dependence of antibiotics used in livestock animals. Recent reports have demonstrated the positive effect of Propionibacterium acnes (P. acnes) to control animal diseases. In this study, we evaluated the effect of the non-specific immunostimulant P. acnes on immunological functions and growth performance in goat kids. Twenty five goat kids served as control group (A) and another 25 animals received P. acnes being the experimental group (B). Kids were challenged with ovalbumin (OVA) to assess humoral immunity. To assess in vivo cell immunity, delayed type hypersensitivity (DTH) test with phytohemagglutinin (PHA) was used, clinical signs and body weight were recorded each week until 9 weeks of age when the experiment ended. Blood samples were obtained to analyze serum proteins fractions and anti-OVA specific antibodies. No clinical signs of disease and no differences (p>0.05) on body weight between groups were recorded (7.32±0.81 kg in group A, 7.13±0.65 kg in group B). Goat kids from group B had more total protein (59.8±5g/l) and albumin levels (32.8±3.3g/l) than goat kids from group A (56.6±5.7 g/l, 29.6±3.9 g/l respectively) (p<0.05). DTH response in goat kids from group B on day 42 was higher (p<0.05) than group A. At day 63, goat kids from group receiving P. acnes had higher percentage (85.4) of anti-OVA IgM titers (p