Progress of Conjugated Linoleic Acid on Milk Fat Metabolism in Ruminants and Humans

Abstract

As a valuable nutrient in milk, fat accounts for a significant proportion of the energy requirements of ruminants and is largely responsible for determining milk quality. Fatty acids (FAs) are a pivotal component of milk fat. Conjugated linoleic acid (CLA) is one of the naturally occurring FAs prevalent in ruminant dairy products and meat. Increasing attention has been given to CLA because of its anti-cancer, anti-inflammatory, immune regulation, and lipid metabolism regulation properties, and these benefits potentially contribute to the growth and health of infants. In breast milk, CLA is present in trace amounts, mainly in the form of cis-9, trans-11 CLA. Notably, cis-9, trans-11 CLA improves the milk fat rate while trans-10, cis-12 CLA inhibits it. Apart from having multiple physiological functions, CLA is also a pivotal factor in determining the milk quality of ruminants, especially milk fat rate. In response to growing interest in green and healthy functional foods, more and more researchers are exploring the potential of CLA to improve the production performance of animals and the nutritional value of livestock products. Taken together, it is novel and worthwhile to investigate how CLA regulates milk fat synthesis. It is the purpose of this review to clarify the necessity for studying CLA in ruminant milk fat and breast milk fat.

The Effects of trans-10, cis-12 Conjugated Linoleic Acid on the Production Performance of Dairy Cows and the Expression and Transcription Regulation of Lipid Metabolism-Related Genes in Bovine Mammary Epithelial Cells

“…The impact of dietary factors on milk composition is crucial, where high-concentrate diets can result in MFD. Among various hypotheses proposed regarding MFD, the trans-fatty acid theory, particularly t 10 c 12-CLA, has gained widespread recognition as an effective inhibitor of milk fat biosynthesis. , As milk fat is primarily composed of TGs, t 10 c 12-CLA can inhibit the synthesis of TGs in milk fat. Under normal physiological conditions, TG in cells is synthesized in the endoplasmic reticulum, where the synthesized TAGs aggregate into small lipid droplets.…”