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, HerbertHA
• 金额: $ 7.59万
• 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: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=743508
• 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.

萨斯喀彻温省大学的研究人员发现，在怀孕后期的肉牛日粮中添加油菜籽脂肪颗粒，会导致小牛从出生到屠宰的生长速度更快，相当于增加了22公斤的屠体。对照饮食和脂肪补充饮食之间的差异在于饮食能量的来源，而不是数量。在对照日粮中，能量来自干草、大麦秸秆和大麦籽粒，而在颗粒饲料中，能量主要来自大麦籽粒，少量由干草和大麦秸秆提供的能量被脂肪颗粒取代。控制生长和肌肉发育的基因的表达也受到产前饮食的影响。该基因还受DNA甲基化的控制，DNA甲基化是DNA的一种修饰，可以通过一般营养改变，有时也可以永久地通过产前营养改变。基因表达的差异可能表明，怀孕期间补充脂肪已经永久性地改变了这些奶牛小牛的基因表达方式，这种差异可能是造成小牛生长差异的原因之一。拟议中的研究将测试这些结果的重复性，并找到产前饮食中油菜籽脂肪的最佳水平。将在出生、断奶和屠宰时采集暴露在产前饲料中的犊牛的血液，以确定表观遗传学和代谢物特征的差异。从根本上推动新陈代谢和生长的组织将在屠宰时收集，以确定产前补充脂肪是否影响组织本身的DNA甲基化和基因表达。在出生和断奶时测量的血液DNA甲基化和代谢物谱将被用于预测出生后生长，以及DNA甲基化模式和代谢重要组织中的基因表达。了解产前营养与出生后生长发育之间联系的生物和表观遗传途径，可以提高对犊牛生产性能的可预测性，并提出新的策略来改善出生后生长。