High-Condensed Tannin Diet and Transportation Stress in Goats: Effects on Physiological Responses, Gut Microbial Counts and Meat Quality

Preslaughter management of goats can affect their welfare and productivity, as well as the resultant product quality. Inclusion of high-condensed tannin ingredients in the diet and minimizing stress can improve meat quality and safety in goats. This study was conducted to determine the effects of transportation stress and sericea lespedeza hay diet on physiological responses, gastrointestinal microbial populations, and meat quality in Spanish goats. Although transportation stress influenced physiological responses, it did not influence muscle pH, which is an important variable that affects the eating quality of meat. Sericea improved anti-inflammatory property and decreased microbial counts in the rumen and rectum of goats. There is evidence that feeding high-condensed tannin diet could be beneficial in meat goat production. Feeding condensed tannin (CT)-containing diets such as sericea lespedeza (Lespedeza cuneata) and reducing stress have been reported to improve meat quality and food safety in goats. In a completely randomized design with split-plot, thirty-six uncastrated male Spanish goats were assigned to 3 dietary treatments (n = 12/treatment): ground 'Serala' sericea lespedeza hay (SER), bermudagrass (Cynodon dactylon) hay (BG), or bermudagrass hay-dewormed goats (BG-DW; Control) at 75% of intake, with a corn-based supplementation (25%) for 8 weeks. Prior to slaughter, goats were either transported for 90 min to impose stress or held in pens. Basophil counts were lower (p < 0.01) in the SER group compared to BG or BG-DW groups suggesting a better anti-inflammatory capacity due to polyphenols in the SER diet. Compared to BG-DW group, cortisol level was higher (p < 0.05) and norepinephrine was lower (p < 0.05) in the SER group. The SER group had the lowest aerobic plate counts (APC) in both rumen and rectum (p < 0.01). Longissimus dorsi muscle initial pH was not affected by diet or stress. Feeding sericea hay to goats may have beneficial effects, such as enhanced antioxidant and anti-inflammatory properties during stress and reduced gut microbial counts, without changing meat quality characteristics.