Regulation of bovine adipose tissue metabolism during lactation. 5. Relationships of lipid synthesis and lipolysis with energy intake and utilization.

摘要: Abstract The effects of energy utilization during lactation on adipose tissue metabolism were determined in 51 first Holstein heifers producing between 5950 and 10,246 kg milk 305 d. Net intake ranged from 18.3 to 40.6 Mcal/d 28 140 d lactation. Milk yield 13.5 47.4 kg/d fat percent 1.49 4.60 d, providing a range 8.2 32.6 secretion. Calculated balance −16.4 11.5 Mcal/d. Weight change −70 143 kg that 112-d period. Subcutaneous was biopsied nine times 30 prepartum 15 after ceased. Adipose lipid synthesis measured negatively related subsequent intake, body weight, weight positively rates 56 but those Lipolysis secretion NE intake. At 60 lactation, function gain, net However, catecholamine-stimulated lipolysis After elevated more closely the previous peak rather than concomitant These relationships demonstrate dietary content genetic selection for production metabolism.