Oral Administration of Lactobacillus amylovorus Alleviates Diarrhea by Restoring Gut Microbiota and SCFAs in Neonatal Goats

Diarrhea in kids is a significant health and economic concern for small-scale ruminant farms. This study aims to investigate the properties of <i>Lactobacillus amylovorus</i> as a treatment for kids with diarrhea and its effect on the composition of the gut microbiota. A total of 20 neonatal goats (approximately 2 months old) were divided into three groups: healthy control (HC, <i>n</i> = 4), diarrhea (D, <i>n</i> = 8), and diarrhea treated with probiotic (DT, <i>n</i> = 8). We tracked gut microbial profiles, fecal consistency, short-chain fatty acids (SCFAs), and clinical symptoms. Probiotic-treated kids recovered fully from diarrhea within two weeks, while their untreated counterparts showed signs of clinical deterioration and gradual emaciation. Kids with diarrhea had lower microbial richness, according to alpha diversity analysis, and this was only partially restored after probiotic treatment. The kids with diarrhea had the lowest Shannon, ACE, Simpson, Dominance, Pielou-e, and Chao1 indices compared to the HC group, while the administration of <i>Lactobacillus amylovorus</i> significantly (<i>p</i> < 0.05) restored their normal enrichment in the DT group compared to the D group. The healthy group had a higher abundance of Verrucomicrobiota, while <i>Firmicutes</i> and <i>Bacteroidota</i> predominated in all groups. <i>Bacteroides</i> and <i>Akkermansia</i> predominated in the healthy and treated groups. At the genus level, analysis showed elevated levels of <i>Escherichia-Shigella</i> and <i>UCG-005</i> in kids with diarrhea. In addition, the concentration of each SCFA in the D group was significantly (<i>p</i> < 0.05) lower than in the HC group. This study provides novel evidence that <i>Lactobacillus amylovorus</i> administration not only alleviates diarrhea but also uniquely restores the production of key SCFAs-including butyrate, acetate, and propionate-in neonatal goats, a finding not previously reported in this species. The concurrent recovery of microbial diversity and SCFA profiles highlights the dual mechanistic potential of <i>Lactobacillus amylovorus</i> as a gut microbiota modulator and metabolic therapeutic in young ruminants. These results lend credence to its potential as a probiotic treatment for small ruminant enteric diseases.