The additive from co-fermented edible plants and probiotics improved calves' growth performance and health by regulating antioxidant and gastrointestinal-microbiota.

OBJECTIVE

The study aimed to assess effects of supplemented co-fermented edible plants and probiotics (AEPP) on growth performance, disease resistance, plasma and rumen metabolites, and bacterial communities in the rumen and feces of pre-weaned calves.

METHODS

Twenty female Holstein calves (7±0.50 d, 41.65±6.20 kg) were randomly assigned to one of two treatments: the control group or the treatment group (30 g/head/day AEPP supplementation). Growth performance, blood, and fecal samples were measured on regular basis. On day 30 of the trial, rumen fluid and fecal samples were collected for multi-omics analysis.

RESULTS

Dietary supplementation with AEPP enhanced calf growth and improved disease resistance, as evidenced by a reduced incidence of respiratory disease and diarrhea and a decreased frequency of antibiotic therapy (p<0.05). The treatment group exhibited enrichment of rumen microorganisms Prevotella, Ruminococcus, and Xylanibacter (linear discriminant analysis>2, p<0.05), along with increased activity in beneficial metabolites such as indoleacetic acid, which activated starch and sucrose metabolism and tryptophan metabolism pathway. This intervetion significantly improved average daily gain, feed efficiency, immunoglobulin G, total superoxide dismutase, and glutathione peroxidase activities, as well as significantly reduced levels of tumor necrosis factor-alpha and interleukin-6 (p<0.05), promoting calf growth and health. The elevated abundance of fecal microorganisms, Subdoligranulum and Bifidobacterium, in the treatment group altered fecal pH, short-chain fatty acids, and butyrate proportions (p<0.05).

CONCLUSION

Feeding AEPP improved growth performance, disease resistance, and antioxidant function. It altered the bacterial communities and metabolic profiles in the rumen and feces of preweaning dairy calves, providing a data reference for the use of AEPP in young ruminant production.