Differences between Yaks and Qaidam Cattle in Digestibilities of Nutrients and Ruminal Concentration of Volatile Fatty Acids Are not Dependent on Feed Level
Hu Liu,
Daozhicairang Wu,
Abraham Allan Degen,
Lizhuang Hao,
Shuiyan Gan,
Hongshan Liu,
Xuliang Cao,
Jianwei Zhou,
Ruijun Long
Affiliations
Hu Liu
State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Centre of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
Daozhicairang Wu
State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Centre of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
Abraham Allan Degen
Desert Animal Adaptations and Husbandry, Wyler Department of Dryland Agriculture, Blaustein Institutes for Desert Research, Ben-Gurion University of Negev, Beer Sheva 8410500, Israel
Lizhuang Hao
Key Laboratory of Plateau Grazing Animal Nutrition and Feed Science of Qinghai Province, Qinghai Academy of Animal Science and Veterinary Medicine, State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
Shuiyan Gan
State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Centre of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
Hongshan Liu
State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Centre of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
Xuliang Cao
State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Centre of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
Jianwei Zhou
State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Centre of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
Ruijun Long
International Centre for Tibetan Plateau Ecosystem Management, College of Ecology, Lanzhou University, Lanzhou 730020, China
The Qinghai–Tibetan Plateau (QTP) is characterized by highly fluctuating seasonal pastures. Yaks (Bos grunniens) graze at higher altitudes than Qaidam cattle (Bos taurus), but the two bovine species co-graze in their overlapping ranges. We hypothesized that yaks would digest nutrients to a greater extent and utilize energy more efficiently than cattle at low dietary intakes, but the difference between bovine species would not be apparent at high intakes. To test this hypothesis, six yaks (203 ± 6.0 kg) and six Qaidam cattle (214 ± 9.0 kg), all 3.5-year-old castrated males, were used in two concurrent 4 × 4 Latin square designs with two extra steers of each species in each period. The digestibilities of dry matter, organic matter, crude protein, ether extract, neutral and acid detergent fiber were greater (p p p p −0.75 d−1, which was lesser (p −0.75 d−1 in cattle. We concluded that: (1) when differences between breeds emerged, the differences existed for all FLs; (2) maintenance energy requirement was lesser and ADG was greater in yaks than in cattle; (3) the digestibilities of nutrients were greater in yaks than in cattle when consuming only oat hay pellets. These findings indicate that yaks adapt to fluctuating dietary intakes in harsh environments by having a low energy requirement and high digestibility of nutrients, independent of the FL.
