Effect of ensiling gliricidia with cassava on silage quality, growth performance, digestibility, ingestive behavior and carcass traits in lambs

The objective of this study was to evaluate the effects of ensiling gliricidia (Gliricidia sepium Jacq.) with cassava on silage quality as well as the growth performance, digestibility, ingestive behavior and carcass traits in lambs. Gliricidia was ensiled with cassava leaves at varying proportions of inclusion (0, 200, 400 and 600 g/kg) for 75 days and fed as a total mixed ration (TMR) at 700 g/kg, while a concentrate mixture was fed at 300 g/kg to 32 castrated Santa Ines crossbred lambs with an average weight of 18.9 ± 2.0 kg. The pH, N-NH3, density, butyric and acetic acid contents and dry matter losses (DML) of the gliricidia silages decreased linearly (P < 0.05) with cassava inclusion, but there was a linear increase (P < 0.05) in the contents of dry matter (DM), non-fibrous carbohydrates (NFC), total carbohydrates (TC), and lactic and propionic acids. Including cassava leaves in the gliricidia silage increased (P < 0.05) the intake (g/d) of DM, CP, EE, NDFap and NDFap (%BW) by the lambs, but there was no effect on the digestibility of DM, CP, EE, and NDFap or the time spent feeding, ruminating, idling and chewing. There was a slight tendency toward a quadratic increase in the NFC digestibility coefficient (P = 0.084). The inclusion of cassava leaves in the gliricidia silage linearly increased (P < 0.05) the final weight, total weight gain, average daily gain, and hot and cold carcass weights of the lambs, but there was no influence on the carcass traits (P > 0.05). However, the weights of the commercial cuts and non-carcass components linearly increased (P < 0.05) with the inclusion of 600 g/kg of cassava in the gliricidia silage. Therefore, it is recommended to combine gliricidia with 600 g/kg of cassava leaves to improve the fermentation pattern and chemical composition of gliricidia-cassava silage, and offering the silage in lamb diets increases the nutrient intake, performance, morphometric measurements and carcass and non-carcass components as well as the yields of both prime commercial cuts, such as the loin and ham, and typical foods, such as sheep "buchada".