Comparative mammalian choline metabolism with emphasis on the high-yielding dairy cow

Abstract

The present review examines the importance of choline in dairy cow nutrition. Choline is an essential nutrient for mammals when excess methionine and folate are not available in the diet. The requirement for choline can be met by dietary choline and by transmethylation reactions. Two types of functions for choline are known: functions of choline per se; functions as a methyl donor. The two principal methyl donors in animal metabolism are betaine, a metabolite of choline, and S-adenosyl-methionine, a metabolite of methionine. Choline and methionine are interchangeable with regard to their methyl group-furnishing functions. In adult ruminants, choline is extensively degraded in the rumen; for this reason dietary choline contributes insignificantly to the choline body pool and methyl group metabolism is generally conservative with a relatively low rate of methyl catabolism and an elevated rate of de novo synthesis of methyl groups via the tetrahydrofolate system. In dairy ruminants, the dietary availability of choline is still low, but the output of methylated compounds in milk is high, and precursors from the tetrahydrofolate pathway are limiting, especially at the onset of lactation. Therefore choline may be a limiting nutrient for milk production in high-yielding dairy cows.

Rumen-protected choline and vitamin E supplementation in periparturient dairy goats: effects on milk production and folate, vitamin B12 and vitamin E status

“…The exact mechanism by which vitamin E alone or in combination with choline can affect milk fat is not known. Although it is plausible that choline can have a positive effect on lipid trafficking and lipid transport to extra-hepatic tissues, including the mammary gland (see Pinotti et al, 2002 for references), effects of vitamin E on this situation are difficult to envisage and may merit further investigation.…”

“…In dairy ruminants, the dietary availability of choline is still low, but the output of methylated compounds in milk is high, and precursors from the tetrahydrofolate pathway are often limiting, especially at the onset of lactation (Pinotti et al, 2002;Girard and Matte, 2004). Based on those considerations, the effects of rumen-protected choline (RPC) supplementation to transition cows have been investigated in several studies.…”

Effects of rumen-protected choline supplementation on milk production and choline supply of periparturient dairy cows

“…Earlier studies (Piepenbrink and Overton, 2000;Pinotti et al, 2002;Cooke et al, 2007) suggested that high-producing cows may be choline deficient around parturition, which adversely affects liver functions, especially the synthesis and secretion of VLDL. Higher choline supply may increase milk production (Erdman and Sharma, 1991;Hartwell et al, 2000;Pinotti et al, 2003) but this response is strongly influenced by -E-mail: husveth@georgikon.hu other nutrients such as protein and methionine (Emmanuel and Kennelly, 1984;Hartwell et al, 2000;Brü semeister and Sü dekum, 2006).…”

Effect of Pre-partum Rumen Protected Choline and Energy Supplementation on the Post-partum Milk Production and Metabolic Profile of Cross Bred Dairy Cows

“…This may be due to the fact RPC can reduce non-esterified fatty acid concentration in plasma which contribute majority of fatty acids secreted by the mammary glands in dairy cows (Pinotti et al, 2002;Cooke et al, 2008). Change in Fat% can also be understood by the fact that it is negatively correlated with milk yield.…”