1. Increasing roughage quality by using alfalfa hay as a substitute for concentrate mitigates CH 4 emissions and urinary N and ammonia excretion from dry ewes
- Author
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Cheng Zhang, Fujiang Hou, Chunmei Wang, Shenghua Chang, Tianhai Yan, Metha Wanapat, and Wanhe Zhu
- Subjects
Dietary Fiber ,Nitrogen ,methane emissions ,Urinary system ,Urine ,Excretion ,Ammonia ,chemistry.chemical_compound ,Animal science ,Food Animals ,Latin square ,Animals ,alfalfa hay ,Feces ,Sheep ,food and beverages ,Original Articles ,Ruminants ,concentrate supplementation ,Straw ,Animal Feed ,Manure ,Diet ,chemistry ,nutrient digestibility ,Original Article ,Animal Nutritional Physiological Phenomena ,Female ,Animal Science and Zoology ,N utilisation ,Methane ,Medicago sativa - Abstract
Twelve Hu sheep × thin‐tail Han crossbred dry ewes with an average body weight of 32.6 ± 0.68 kg and an age of 3 years were arranged in a 3 × 3 Latin square design, with each experimental period of 24 d to evaluate the effect of substituting alfalfa hay in a portion of concentrate on nutrient intake, digestibility, N utilisation efficiency and methane emissions. The ratios of corn straw to alfalfa to concentrate for 3 diet treatments were 60:0:40, 60:15:25 and 60:30:10, respectively. Intake and digestibility were measured for each of the ewes, which were housed in individual metabolism crates for 6 d after an adaptation period of 14 d, and the feed was offered at 1.2 MEm to ensure approximately 10% orts. Methane emissions were determined in a respiration chamber for 2 consecutive d. An increase in the levels of alfalfa as a substitute for concentrate significantly increased the roughage, NSC and ADF intake and faecal N output as a proportion of N intake and manure N output. Furthermore, this increase in alfalfa input levels decreased DE, ME and N intake; nutrient digestibility; DE/GE, ME/GE and CH4 emissions per day; CH4 output expressed as a portion of the DM, OM and GE intake; and urinary N and ammonia N output, especially between extreme treatments. Alfalfa input levels had no effect on the BW, DM and GE intake; the EB or EB/GE intake; and the retained N. This study indicated that increasing alfalfa input as a substitute for concentrate could significantly decrease the digestibility, CH4 emissions and urinary N and NH4 +‐N outputs; and shift the N excretion from urine to faeces; and could sustain a similar DM intake.
- Published
- 2019