Productive and metabolic increments of the inclusion of Broussonetia papyrifera to replace maize silage in growing goats

The study was conducted to investigate the effects of Broussonetia papyrifera (BP) on growth performance, rumen fermentation, digestion and meat quality in Huanghuai white goats. Diets were developed with increasing doses of BP to replace maize silage [0% (control), 15% (BP15), 30% (BP30) and 45% (BP45)]. The design was completely randomized with 4 groups of 10 animals each, totalizing 40 animals (aged 150 ± 10 days and body weight of 25.32 ± 0.52 kg). Final body weight, average daily gain and average daily feed intake increased (linear and quadratic, P < 0.05) as BP increased in the diet. The highest body weight and average daily gain were seen in the BP30 group. Feed conversion ratio also improved significantly (linear and quadratic, P < 0.05) with the increasing level of BP. Although the concentration of microbial protein (MCP) in a linear (P = 0.0028) and quadratic (P = 0.0035) fashion with increasing level of BP, however, NH3-N in a quadratic (P = 0.0841) fashion with increasing level of BP. Crude protein was increased with increasing BP in the diets (linear and quadratic, P < 0.05). Nitrogen intake, urinary excretion nitrogen and nitrogen retention were significantly improved (linear and quadratic, P < 0.05) with dietary BP addition in goats. Dietary BP supplementation increased pH (linear and quadratic, P < 0.05) and tended to reduce L* (lightness) (linear and quadratic, P < 0.05). Additionally, the redness value of meat was significantly improved by BP addition (linear and quadratic, P < 0.05). The inclusion of BP in the goat diet promotes growth and increases the digestibility of crude protein in addition to improving the meat colour and rumen fermentation.