畜牧兽医学报2020，Vol.51Issue(6)：1295-1305,11.DOI:10.11843/j.issn.0366-6964.2020.06.013
饲粮能量水平对13～18月龄荷斯坦阉牛生产性能和屠宰指标的影响
Effects of Dietary Energy Level on Production Performance and Slaughter Indicators of 13-18 Months Old Holstein Steers
摘要
Abstract
The effects of different dietary energy levels on production performance and slaughter indicators of 13-18 months old Holstein steers were investigated in this study. Sixty 13-month-old healthy Holstein steers with average body weight of (501.17±20. 09)kg were selected and randomly divided into 3 groups with 20 replicates in each group and 1 steer in each replicate. According to the energy level of the diets，3 groups were low energy group(LE)，medium energy group (ME) and high energy group(HE)，respectively. The whole experiment lasted for 154 days with a 10-day pretest period and a 144-day formal test period. The comprehensive net energy (NEmf) of the diets in the early stage of the experiment(97 d) were 5. 90，6. 10 and 6. 30 MJ?kg-1，respectively. The NEmf of the diets in the later stage of the experiment(47 d) were 6. 10，6. 30 and 6. 50 MJ?kg-1，respectively. The crude protein level of the diets in the whole experiment was 11.50%.At the end of the feeding experiment，the production performance and other indicators were measured. Five steers were randomly selected from each group to collect blood sample for determination of blood biochemical indicators and slaughtered for determination of slaughtering performance and meat quality. The results showed that the different dietary energy levels had no significant effect on the average daily gain (ADG) of the Holstein steers during the whole experimental period(P＞0.05).Compared with LE group，the feed to gain ratio of HE group was significantly lower (P＜0.05)，but there was no significant difference between HE group and ME group(P＞0.05);With the increase of dietary dietary energy level，the serum glucose content in the HE group was the lowest，which was 16. 04% (P＜0. 05) and 8. 99% (P＜0. 05) lower than those of LE group and ME group，respectively. The content of serum urea nitrogen of ME group was the lowest，which was 8. 52% lower than that of LE group(P＜0.05)，and there was no significant difference between ME group and HE group (P＞0.05).The content ofβ-hydroxybutyric acid and growth hormone decreased significantly with the increase of dietary energy (P＜0.05)，and the activity of serum lipoprotein lipase increased with the increase of dietary energy level (P＜0.05);With the increase of dietary energy level，body height decreased significantly(P<0. 05)，but there was no significant effect on body length and heart girth(P＞0.05);The loin eye area of Holstein steers increased significantly with the increase of dietary energy level (P<0..05)，but the dietary energy level had no effect on dressing percentage，net meat rate and meat to bone ratio(P＞0.05);The content of crude fat in longissimus dorsi muscle in HE group was significantly increased (P<0.05) and the content of water was significantly reduced (P＜0.05) compared to LE group; The income of ME group was the highest，which was 0.97 yuan? (day?head)-1 and 1.02 yuan? (day?head)-1 higher than those of LE group and HE group，respectively. In summary，under the conditions of this experiment，when the dietary CP level of 13-18 months old Holstein steers was 11.50%，the suitable NEmf level in the early period was 6. 10 MJ?kg-1 , and the suitable NEmf level in the later period is 6. 30 MJ?kg-1.关键词
能量/荷斯坦阉牛/生产性能/屠宰指标Key words
energy/Holstein steers/growth performance/slaughter indicators分类
农业科技引用本文复制引用
张美琦1,李妍2,李树静3,高艳霞1,李建国1,曹玉凤1*,李秋凤1*..饲粮能量水平对13～18月龄荷斯坦阉牛生产性能和屠宰指标的影响[J].畜牧兽医学报,2020,51(6):1295-1305,11.基金项目
国家肉牛牦牛产业技术体系建设项目(CARS-37) （CARS-37）
河北省现代产业技术体系肉牛创新团队(HBCT2018130202) （HBCT2018130202）
