77 Responses to alfalfa supplementation in mice

Abstract

Abstract Anecdotal evidence suggests health benefits from feeding late cutting alfalfa to non-ruminants, but there is a lack of published literature to support these claims. The objective was to compare early (1st) and late (5th) cutting alfalfa as ground hay, aqueous, or chloroform-extracted hay in combination with a gastrointestinal challenge to understand the effect of supplementation form and cutting on the overall health, microbiome, and immune system of mice. 163 C57BL/6J mice were housed for 35 d (Innovive system; 2–4 mice/cage) and fed treatments that consisted of an 18% protein rodent diet (alfalfa-free control), or control supplemented with 1st or 5th cutting 9% ground alfalfa hay, 0.25% aqueous extract (AAE), or 0.25% chloroform extract (CAE). After a 14 d enrichment period, 6 mice/treatment were euthanized for baseline tissue and digesta sampling, and remaining mice were orally gavaged with 2x1010 CFU Citrobacter rodentium. On d18, 22, 28, and 35, 4 mice/treatment were euthanized for sampling. Body weight (BW) and feed intake (FI) were recorded, 13 serum cytokines were measured, and changes in the microbial communities were analyzed using 16S rRNA amplicon sequencing. Data were analyzed using PROC MIXED and linear discrimination analysis effect size (LEfSe), with significance at P ≤ 0.05. No BW differences were observed between treatments at the key timepoints (P > 0.05). Mice fed hay diets ate 16% more per day during the enrichment period (P = 0.03), 19% more from d14–18 (P = 0.001), and 17% more from d18–22 (P = 0.03) versus mice fed AAE. Citrobacter rodentium infection was confirmed via MiSeq in colon digesta. Significant shifts in microbial taxa were observed in mice fed alfalfa hay regardless of cutting (P < 0.05). Cytokine analysis, flow cytometry, and microbiome analysis is ongoing. Preliminary results show that alfalfa form significantly impacts FI and microbiome while cutting impacts weight (P < 0.05).