Level of Fat from Canola Seed Supplementation in Pregnant Beef Cow Diets - Effects on Cow and Calf Performance

怀孕肉牛日粮中添加双低油菜籽的脂肪水平 - 对奶牛和犊牛生产性能的影响

• 批准号: 558272-2020
• 负责人: Lardner, Herbert
• 金额: $ 6.66万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Alliance Grants
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=706723
• 关键词: Level; Fat; Canola; Seed; Supplementation

Researchers from the University of Saskatchewan found that canola-fat based pellet supplementation in the diet of beef cows during late pregnancy led to greater growth of their calves from birth to slaughter, translating into 22 kg more carcass. The difference between the control diet and the fat-supplemented diet was the source, not the amount, of dietary energy. In the control diet energy came from hay, barley straw, and barley grain, while in the pellet-supplemented diet energy came largely from barley grain with a slight amount of the energy supplied by the hay and barley straw replaced by the fat-pellet. Expression of a gene that controls growth and muscle development was also affected by prenatal diet. This gene is also under the control of DNA methylation, a modification of DNA that can be altered by general nutrition, and sometimes permanently by prenatal nutrition. The difference in gene expression could indicate that fat supplementation during pregnancy has permanently altered the way genes are expressed in the calves of these cows, and this difference may be contributing to the growth difference in the calves. The proposed research will test the repeatability of these results, and find an optimal level of inclusion of canola-fat in the prenatal diet. Blood will be collected at birth, weaning, and slaughter from steer calves exposed to the prenatal diets to identify differences in epigenetic and metabolite profiles. Tissues fundamentally driving metabolism and growth will be collected at slaughter to determine if prenatal fat supplementation affects DNA methylation and gene expression within the tissues themselves. Blood DNA methylation and metabolite profiles measured at birth and weaning will be examined for use as predictors of postnatal growth, and patterns of DNA methylation and gene expression in metabolically important tissues. Understanding biologic and epigenetic pathways that underlie connections between prenatal nutrition and postnatal growth and development can lead to increased predictability of calf performance and novel strategies to improve postnatal growth.

萨斯喀彻温大学的研究人员发现，在肉牛妊娠后期的饮食中添加基于芥花籽脂肪的颗粒补充剂，可以使小牛从出生到屠宰的生长更快，转化为屠宰量增加 22 公斤。对照饮食和补充脂肪的饮食之间的差异在于膳食能量的来源，而不是数量。在对照日粮中，能量来自干草、大麦秸秆和大麦谷物，而在颗粒补充日粮中，能量主要来自大麦谷物，少量干草和大麦秸秆提供的能量被脂肪颗粒替代。 控制生长和肌肉发育的基因表达也受到产前饮食的影响。该基因也受到 DNA 甲基化的控制，DNA 甲基化是一种 DNA 修饰，可以通过一般营养改变，有时可以通过产前营养永久改变。基因表达的差异可能表明，怀孕期间补充脂肪永久改变了这些奶牛犊牛中基因的表达方式，这种差异可能导致了犊牛的生长差异。 拟议的研究将测试这些结果的可重复性，并找到产前饮食中芥花籽脂肪的最佳含量。将在出生、断奶和屠宰时从接触产前饮食的小牛身上采集血液，以鉴定表观遗传和代谢谱的差异。将在屠宰时收集从根本上驱动新陈代谢和生长的组织，以确定产前脂肪补充是否会影响组织本身内的 DNA 甲基化和基因表达。将检查出生和断奶时测量的血液 DNA 甲基化和代谢物谱，以用作出生后生长以及代谢重要组织中 DNA 甲基化和基因表达模式的预测因子。 了解产前营养与产后生长发育之间联系的生物学和表观遗传途径可以提高犊牛性能的可预测性，并制定改善产后生长的新策略。