Denovo synthesized fatty acids as regulators of milk fat synthesis

摘要: Title of document: DENOVO SYNTHESIZED FATTY ACIDS AS REGULATORS OF MILK FAT SYNTHESIS Diwakar Vyas, Doctor Philosophy, 2011 Directed By: Professor Richard A. Erdman Department Animal and Avian Sciences The objectives the dissertation research were to determine role denovo synthesized fatty acids (DNFA) in regulation milk fat synthesis. Milk responses increasing amounts shortand medium-chain (SMCFA), added proportion as denovo, studied lactating dairy cows. results showed a significant linear increase concentration with SMCFA supplementation. However, yield was similar for all treatments. A subsequent study aimed at availability during trans-10, cis-12 CLA-induced depression (MFD) cows whether can rescue part MFD. Post-ruminal infusion butterfat (BF) used source SMCFA. BF treatment compared mixture fats containing only long-chain FA (LCFA) or without CLA infusion. content significantly reduced CLA. increased had no effects on concentration. Trans-10, mRNA expression transcription factor SREBP-1c along its downstream targets including ACC, FASN, LPL, SCD AGPAT. effect either lipogenic gene protein suggesting that nutritional manipulation not sufficient Finally, combination Rosiglitazone (ROSI), PPAR-γ agonist, examined mammary hepatic lipogenesis mice. Mammary CLA, reducing factors SREBP1-c PPARγ. lipid accumulation, while PPARγ altered. On contrary, ROSI lipogenesis. rescued steatosis.