Sixty dairy goats of the Polish white improved breed were randomly assigned to five feeding groups of twelve animals each. The animals received a supplement containing seven herbs at 20 or 40 g/animal/day (experimental groups 1 and 2) and a supplement containing nine herbs at 20 or 40 g/animal/day (experimental groups 3 and 4)m, along with pelleted concentrate feed. Group 5 (the control group) received pelleted feed without any herbal supplements. A significant effect of herbal feed additive on lactic acid bacteria (LAB) count was observed (p < 0.001). The highest number density of LAB was found in the goats receiving the feed additive with nine herbs at 20 g/animal per day (p < 0.05). There was a statistically significant effect of lactation stage on intestinal LAB count (p < 0.001). Regardless of the feeding group, the highest number density of LAB was found in animals at the peak of lactation. The LAB count was also affected by the interaction of diet group × lactation stage (p < 0.0001). A probiotic strain of Lactobacillus fermentum was identified in the faecal samples of goats receiving the herbal additive, but not in the controls. Genetic identification of the microorganisms isolated from the faeces of the experimental goats did not reveal the presence of harmful mould spores, although spores of the fungus Aspergillus fumigatus were detected in the controls.
Keywords: dairy goats; herbal feed additives; intestinal lactic acid bacteria (LAB).