Carotene and immunoglobulin concentrations in the colostrum and milk of pasture-fed cows
Summary The 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.
EFFECTS OF FEEDING COLOSTRUM AND MILK OF HOLSTEIN COWS ON GROWTH RATE , IMMUNOGLOBULIN LEVELS AND METABOLIC TRAITS IN JERSEY CALVES PRODUCED BY EMBRYO TRANSFER : COMPARISON WITH HOLSTEIN CALVES
The aim of the present study was to assess the effects of Holstein dam’s colostrum and milk on growth rate, immunoglobulin levels, and metabolic traits in Jersey calves produced by embryo transfer: comparison with Holstein calves. All calves received colostrum within half an hour after birth at the rate of 2.4-3.9 L were 10% BW basis, and continued for the first 3 days and milk from after that to weaning at 8 weeks; they were fed twice daily in equal amounts more or less 5-10% of their BW. Also, calves were provided water ad libitum, grass hay, and calf starter at 7 days after birth. Results exhibited the content and immunoglobulin levels of colostrum gradually decreased with increasing age after birth. Jersey calves had lower BW (P<0.05) at preweaning period and mean ADG over 56 days compared with Holstein calves (P>0.05). However, feed efficiency was higher in Jersey than in Holstein calves (P>0.05). The level of plasma IgG was over 10 mg/mL, which indicated the successful transfer of passive immunity in Jersey and Holstein calves. Indeed, feeding the milk of Holstein dams did not significantly affect plasma total protein, glucose, urea nitrogen, and NEFA concentrations of Jersey calves as compared with Holstein calves. Therefore, these data suggest that feeding Holstein dam’s milk will not affect the growth performance, immunoglobulin level and metabolic traits of Jersey calves produced by embryo transfer.
Nursing theory and administrative practice: Agenda for the 1990s
&NA; Despite past progress in the development of nursing theory, a theoretical nursing perspective is not yet common to the practice of nursing administration. Such a perspective could serve as a catalyst both to advance knowledge development for administrative nursing practice and to align clinical and administrative practice within a common framework. In this article assumptions, concepts, and questions common to both clinical and administrative nursing practice are identified. Select domain concepts are used to exemplify the themes shared by nurse clinicians and nurse administrators. The article concludes with a five‐item agenda as a guide for future theory development.