Common vetch hay and the influence of Yucao on the digestibility, metabolism, and greenhouse gas emissions of lambs

To study the effects of common vetch (Vicia sativa) and Yucao on the digestion and metabolism of livestock, 6-month-old hybrid rams were fed one of the following three diets: diet 1, 100% Yucao; diet 2, 30% V. sativa and 70% Yucao; diet 3, 45% V. sativa and 55% Yucao. Results showed that 1) dry matter intake and the digestibility of Diet 3 were higher than Diet 1 and Diet 2; 2) the neutral detergent fiber and crude protein digestibility of Diet 3 were significantly higher than Diet 1 and Diet 2 (P < 0.05); and 3) a mixed diet of V. sativa and Yucao reduced greenhouse gas emissions, which were the lowest in Diet 2. However, there was no significant difference in oxygen consumption, methane emissions, or carbon dioxide emissions per unit of dry matter intake between Diet 2 and Diet 3. Based on the above results, a diet of 45% V. sativa + 55% Yucao will increase feed digestion and metabolism by lambs and at the same time, can be used as an effective greenhouse gas emission reduction measure in animal husbandry.