Nutraceutical Effects of Fertilized and Unfertilized Sericea Lespedeza Hay on Gastrointestinal Parasitism and Whole-Plasma Metabolome of Naturally Infected Goats

Abstract The objective of this study was assessing the effect of the dietary inclusion of unfertilized (AS) and fertilized (AR) Sericea lespedeza hay on the parasitic burden, packed cellular volume (PCV), and whole-plasma metabolome of naturally infected goats. Thirty-six naturally parasite-infected (>5,000 eggs/gram) Spanish goats (23.9 ± 0.15 kg) were randomly allocated (12 goats per treatment) into three dietary treatments: a) Control (Bermudagrass hay), AS (Unfertilized lespedeza), and AR (fertilized lespedeza) for 60 days. All treatments were supplemented with a commercial concentrate following a 70:30 forage: concentrate ratio. Feed samples, blood samples, and fecal samples were collected and recorded weekly to estimate chemical composition, fecal egg counts, and PCV. Additionally, whole-plasma metabolomic analysis was performed using chemical isotope labelling/liquid chromatography-mass spectrometry-based technique. Pathway enrichment analysis and analysis of the differentially abundant metabolites were performed using MetaboAnalyst 5.0 software. Data were analyzed with the GLIMMIX procedure (repeated measures) of SAS with the fixed effect of treatment, week, and the random effect of animals. Total condensed tannins and precipitable phenolics were greater (P < 0.05) in AS compared with AR (13.9 vs. 6.5% DM; 95.3 vs.9.5 mg/g). However, both AS and AR reduced (P < 0.01) fecal egg counts compared with the control (1,100, 1,450 vs. 3,500 eggs/gram). Conversely, PCV was greater in AR compared with the control (23.6 vs. 20.6%), but no differences between AR and AS (23.6 vs. 22.5%) were observed. Compared with the control, relative distribution of glutamine and beta-leucine were increased in AS and AR. The pathway enrichment analysis revealed that dietary AS and AR increased glycine, serine, and purine metabolism compared with the control. Collectively, results from this study suggest that dietary AS and AR reduced fecal egg counts by improving anti-oxidative metabolism, muscle regeneration capacity, and immune response in naturally infected goats.