Effects of dietary protein level on growth performance and nitrogen excretion of dairy heifers
2
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
Objective: Protein supplementation is costly and can result in excess nitrogen (N) excretion. The objective of this study was to evaluate the effects of feeding different levels of dietary protein on average daily gain, body size, rumen fermentation, and nitrogen excretion of 8 to 10 month-old Holstein heifers. Methods: Thirty-six Holstein heifers were divided into 12 blocks according to age (273±6.2 d) and were randomly assigned to diets containing a low (10.2% dry matter [DM]), medium (11.9% DM), or high (13.5% DM) level of dietary crude protein (CP). All diets contained approximately 70% roughage and 30% concentrate with similar dietary metabolizable energy (ME) content (2.47 Mcal/kg). Results: Dry matter intake did not differ among the treatments, and average daily gain increased with the increasing dietary protein, 0.79, 0.95, 0.97 kg/d for low, medium, and high group, respectively. Body height increased linearly with increasing dietary CP but no other significant differences in body dimensions were found among the treatments. The increased ratios of dietary CP improved the rate of rear teat length growth remarkably (p<0.05). There was no difference in rumen pH or ruminal major volatile fatty acid (acetate, propionate, and butyrate) concentration among the 3 diets, but rumen ammonia-N concentration increased with the higher dietary CP (p<0.05). Increasing N intake led to increased total N excretion; urinary N excretion was significantly increased (p<0.05) but fecal N excretion was similar among the treatments. Conclusion: These data suggest that the diet containing 11.9% CP (ME 2.47 Mcal/kg) could meet the maintenance and growth requirements of 9 to 11 month-old Holstein heifers gaining approximately 0.9 kg/d.
Abstract
Objective: Protein supplementation is costly and can result in excess nitrogen (N) excretion. The objective of this study was to evaluate the effects of feeding different levels of dietary protein on average daily gain, body size, rumen fermentation, and nitrogen excretion of 8 to 10 month-old Holstein heifers. Methods: Thirty-six Holstein heifers were divided into 12 blocks according to age (273±6.2 d) and were randomly assigned to diets containing a low (10.2% dry matter [DM]), medium (11.9% DM), or high (13.5% DM) level of dietary crude protein (CP). All diets contained approximately 70% roughage and 30% concentrate with similar dietary metabolizable energy (ME) content (2.47 Mcal/kg). Results: Dry matter intake did not differ among the treatments, and average daily gain increased with the increasing dietary protein, 0.79, 0.95, 0.97 kg/d for low, medium, and high group, respectively. Body height increased linearly with increasing dietary CP but no other significant differences in body dimensions were found among the treatments. The increased ratios of dietary CP improved the rate of rear teat length growth remarkably (p<0.05). There was no difference in rumen pH or ruminal major volatile fatty acid (acetate, propionate, and butyrate) concentration among the 3 diets, but rumen ammonia-N concentration increased with the higher dietary CP (p<0.05). Increasing N intake led to increased total N excretion; urinary N excretion was significantly increased (p<0.05) but fecal N excretion was similar among the treatments. Conclusion: These data suggest that the diet containing 11.9% CP (ME 2.47 Mcal/kg) could meet the maintenance and growth requirements of 9 to 11 month-old Holstein heifers gaining approximately 0.9 kg/d.
참고문헌 (29)
- Imura H, "Environmental issues in China today" (2013), Springer-Verlag
- Li RG, "Pollutants sources and their discharging amount in Taihu Lake Area of Jiangsu Province", J Lake Sci, 8, pp.147~153 (2000)
- Guo C, "The analysis of diets feed nutrients and the status of nitrogen and phosphorus use in scale dairy farms which are in the eastern region", pp.2013
- National Research Council, "Nutrient requirements of dairy cattle" (2001), National Academy Press
- Wang C, "Effect of dietary phosphorus content on milk production and phosphorus excretion in dairy cows", J Anim Sci Biotechnol, 5, pp.23~28 (2014)
- B. Zhang, "The Effects of Dietary Phosphorus on the Growth Performance and Phosphorus Excretion of Dairy Heifers", ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES, 29(7), pp.960~964 (2016), 아세아·태평양축산학회[DOI]
- Broderick GA, "Effects of varying dietary protein and energy levels on the production of lactating dairy cows", J Dairy Sci, 86, pp.1370~1381 (2003)
- O’Colmenero JJ, "Effect of dietary crude protein concentration on milk production and nitrogen utilization in lactating dairy cows", J Dairy Sci, 89, pp.1704~1712 (2006)
- Tuijian-34, "Feeding standard of dairy cattle. China Nong Ye Hang Ye Biao Zhun", pp.Agricultural Publisher, China Standard NY
- AOAC International, "Official methods of analysis of AOAC International" (2012), AOAC International
- Van Soest PJ, "Methods of dietary fiber, NDF and non-starch polysaccharides in relation to animal nutrition", J Dairy Sci, 15, pp.3583~3597 (1991)
- Shen JS, "Insertion depth of oral stomach tubes may affect the fermentation parameters of ruminal fluid collected in dairy cows", J Dairy Sci, 95, pp.5978~5984 (2012)
- Hu WL, "Effect of tea saponin on rumen fermentation in vitro", Anim Feed Sci Technol, 120, pp.333~339 (2005)
- Heinrichs AJ, "Predicting body weight and wither height in Holstein heifers using body measurements", J Dairy Sci, 75, pp.3576~3581 (1992)
- Shen JS, "Transfer efficiency of melamine from feed to milk in lactating dairy cows fed with different doses of melamine", J Dairy Sci, 93, pp.2060~2066 (2010)
- Yu Z, "Study on growth and development pattern of Chinese Holstein calf and heifer", China Anim Husb Vet Med, 41, pp.121~125 (2014)
- Kertz AF, "Increased weight gain and effects on growth parameters of Holstein heifer calves from 3 to 12 months of age", J Dairy Sci, 70, pp.1612~1622 (1987)
- Zhang WB, "Effect of dietary protein to metabolizable energy ratio on growth performance and nutrients digestion of 8-10-month-old Chinese Holstein heifers", Sci Agric Sin, 43, pp.2441~2547 (2010)
- Lammers BP, "The response of altering the ratio of dietary protein to energy on growth, feed efficiency, and mammary development in rapidly growing prepubertal heifers", J Dairy Sci, 83, pp.977~983 (2000)
- Gabler MT, "Dietary protein to metabolizable energy ratios on feed efficiency and structural growth of prepubertal Holstein heifers", J Dairy Sci, 86, pp.268~274 (2003)
- Cozler YL, "Rearing strategy and optimizing first calving targets in dairy heifers: a review", Animal, 2, pp.1393~1404 (2008)
- Lin CY, "Inter-correlations among milk traits and body and udder 180 measurements in Holstein heifers", J Dairy Sci, 70, pp.2385~2393 (1987)
- Sejren K, "Influence of prepubertal feeding level on milk yield potential of dairy heifers: a review", J Anim Sci, 75, pp.828~835 (1997)
- Whitlock BK, "Effect of dietary protein on prepubertal mammary development in rapidly growing dairy heifers", J Dairy Sci, 85, pp.1516~1525 (2002)
- Ge RF, "Effects of different dietary metabolizable protein levels on growth and development, blood biochemical indices and body condition scores of 8 to 10-month-old heifers", Chinese J Anim Nutr, 27, pp.910~917 (2015)
- Gabler MT, "Effects of increasing dietary protein on nutrient utilization in heifers", J Dairy Sci, 86, pp.2170~2177 (2003)
- Satter LD, "Effect of ammonia concentration on rumen microbial protein production in vitro", Br J Nutr, 32, pp.199~208 (1974)
- Zanton GI, "Rumen digestion and nutritional efficiency of dairy heifers limit-fed a high forage ration to four levels of dry matter intake", J Dairy Sci, 91, pp.3579~3588 (2008)
- Marini JC, "Nitrogen metabolism and recycling in Holstein heifers", J Anim Sci, 81, pp.545~552 (2003)
