Impact of dry-off and lyophilized Aloe arborescens supplementation on plasma metabolome of dairy cows

Abstract

Positive effects have been observed as a result of Aloe arborescens supplementation in the dry-off phase in dairy cows. Metabolomic approaches can provide additional information about animal physiology. Thus, we characterized plasma metabolome around dry-off in 12 cows supplemented (AL) or not (CTR) with 10 g/d of lyophilized A. arborescens with an untargeted metabolomic approach. Overall, 1658 mass features were annotated. Regardless of treatment, multivariate statistics discriminated samples taken before and after dry-off. Overall, 490 metabolites were different between late lactation and early dry period, of which 237 were shared between AL and CTR. The most discriminant compounds (pentosidine and luteolin 7-O-glucoside) were related to the more fibrous diet. Pathway analysis indicated that pyrimidine and glycerophospholipid metabolisms were down-accumulated, suggesting reduced rumen microbial activity and liver load. Samples from AL were discriminated from CTR either the day of dry-off or 7 days after. At dry-off, aloin and emodin were the most discriminant metabolites, indicating that Aloe's bioactive compounds were absorbed. Seven days later, 534 compounds were different between groups, and emodin was among the most impacted. Pathway analysis highlighted that glycerophospholipid, pyrimidine, and folate metabolisms were affected. These results might indicate that Aloe has positive effects on liver function and a modulatory effect on rumen fermentation.

Aloe arborescens supplementation in drying-off dairy cows: influence on rumen, rectum and milk microbiomes

“…The RABOLA project was the rst scienti c effort to study rumen fermentation, milk production and blood biomarkers upon in vivo supplementation with Aloe spp. during dry-off in dairy cows that did not receive antibiotic therapy but were administered only an internal teat sealant instead [14,40]. The project results revealed altered proportions of volatile fatty acids (VFA) and a reduction in dry fecal content.…”

“…This lack of impact can be attributed to the fact that the samples were analyzed only seven days' post treatment. In fact, the plasma metabolome [40] reveals that Aloe has positive effects when supplemented 7 days before and after dry-off on liver function and have modulatory effect on rumen fermentation.…”

“…These bacteria contribute to the enhancement of animal energy metabolism by producing β-hydroxybutyrate and acetoacetate, which serve as energy substrates for epithelial cells [47]. This process helps to improve the overall energy metabolism of dairy cows, maintain a healthy state of the gut and might also improve the feed e ciency [14,40,[48][49].…”