Carotene and immunoglobulin concentrations in the colostrum and milk of pasture-fed cows

Abstract

SummaryThe carotene and immunoglobulin concentrations in colostra and milks of 6 Jersey, 4 Friesian and 6 Jersey × Friesian cows were determined during the first 21 d of lactation. Carotene concentrations of between 50 and 300 μg/g milk fat were found at first milking and these declined to normal concentrations, in the range 9–21 μg/g milk fat, by the eighth to tenth day of lactation. Immunoglobulin concentrations at first milking were in the range 4–40 g/l milk and decreased to normal concentrations, in the range 0·3–0·5 g/l, by the fifth to seventh day of lactation. For both substances the data from each cow's milk fitted an exponential decay model. The fractional rates of decrease in concentration of carotene were 0·19–0·57/d and of immunoglobulin were 0·40–0·73/d. Breed-group differences were observed in both carotene and immunoglobulin concentrations in milks after the fourteenth day of lactation. In Jersey milks, the average carotene and immunoglobulin concentrations were respectively 18·5 μg/g milk fat and 0·32 g/l of milk, while in Friesian milks the concentrations were respectively 11·4 μg/g milk fat and 0·46 g/l milk. There was also a difference between breed groups in the daily rates of decrease of the immunoglobulin concentrations. The average rate of decrease for the Friesians was about 1·5 times the rate for the Jerseys.

Composition of bovine milk fat globules by confocal Raman microscopy

“…Milk of Jersey cows contains more carotenoids than milk of Friesian and Friesian-Jersey cows (Newstead, 1976). Friesian cows have a lower level of b-carotene and a higher level of vitamin A than Jersey and Guernsey cows (MacGibbon & Taylor, 2006).…”

Management effects on colostrogenesis in small ruminants: a review

“…The different findings among studies, with respect to the effects of either lactation number and the litter size on the colostrum IgG content, may be due to the different breeds used in each experiment, because breed is an important factor that can influence the colostral IgG concentration (Tennant et al 1969;Kruse 1970;Newstead 1976;Halliday et al 1978;Ha et al 1986). Thus non-specialists dairy goats produce higher quality of colostrum than those dairy breeds such as Majorera goats ).…”

Long‐term bromocriptine treatment during late pregnancy has differential effects on milk yields of single‐ and twin‐bearing ewes

“…The continued difference in protein percentage past the first few days in the present trial cannot readily be attributed to differences in immunoglobulin secretion since large concentrations of immunoglobulins are normally present in milk only during the initial stage of lactation, then the pool of immunoglobulin which has accumulated during the prepartum period is washed out (Newstead 1976). Thus, the continued elevation of protein for 4 weeks indicates that protein synthesis was less affected by CB154 treatment than was milk volume (i.e., lactose synthesis).…”