Effects of corn silage intercropped with Marandu grass and pigeon pea on ruminal kinetics and methane production in lambs

This study aimed to evaluate the effects of corn silage intercropped with Marandu grass with or without pigeon pea on lamb’s ruminal kinetics and methane (CH4) production. The experimental design was completely randomised, with two treatments. The in vitro ruminal kinetics, CH4 production, and fermentation parameters of ruminal inoculum were evaluated using 12 lambs (four animals for growing season), in duplicates. Corn silage without pigeon pea showed higher fraction of dry matter degraded (65.37 vs. 60.69% DMd, respectively) in 24–hour incubation and higher fraction of organic matter degraded (83.99 vs. 79.12% OMd, respectively) in 96–hour than silage with pigeon pea. There was no difference in total gas production, short‐chain fatty acids production, and ammonia–N production of the diets. Linear and Quadratic models presented higher coefficient of determination, indicating better fit of these equations to in vitro data during 24–hour, and Dual–pool Logistic model presented the best results during 96–hour. Pigeon pea inclusion did not reduce CH4 production, independently of the incubation period (mean 36.94 and 46.91 ml CH4/g DMd, in 24 and 96–hour, respectively). The study suggests that from a nutritional stance, there were no benefits in using pigeon pea in lamb’s diets.