Meat goat diet supplementation with crude glycerine: Ruminal fermentation metabolism,blood chemistry profile,animal performance and carcass traits

The objective of this experiment was to determine the effects of feeding varying levels of crude glycerine (CG) on dry matter intake (DMI), animal performance, carcass traits and rumen volatile fatty acids (VFA) concentration in meat goats. Twenty-four intact male Boer goats (23.9 ± 1.0 kg initial BW and 4–5 months of age) were randomly assigned to one of four experimental diets (n = 6) containing 30% bermudagrass hay plus 70% concentrate mix with 0, 5, 10 or 15% CG in the diet on an as-fed basis, substituted for the corn portion of the concentrate. Feed offered and refusals were monitored daily for 84 days. Goats were weighed at 28-days interval. Blood and rumen samples were collected on day 84. At the end of the 84-days feeding period, goats were harvested, and carcass characteristics measured. Feed intake, average daily gain (ADG), gain-to-feed ratio (G:F), carcass traits and VFA concentrations were analysed as a completely randomized design. The CG did not influence animal body weight (BW) changes, ADG and G:F ratio but tended to (p = 0.06) decrease DMI. Molar per cent propionic acid increased linearly (p < 0.05) with increasing CG. The acetate: propionate (A:P) ratio decreased (p < 0.05) with increasing amounts of CG in the diet. The CG addition tended to increase (p = 0.09) the longissimus muscle (LM area) in meat goats. In conclusion, CG can replace corn in diet for growing meat goats when fed up to 15% of diet, improving ruminal propionate concentration, but decreasing A:P ratio without affecting animal performance and carcass traits.