Life 8oianaea Vol. 16, pp " 1285-1292 Printed is the U.S .A .
Pergamoa Prese
HORMONE AND METABOLITE DIFFERENCES BETWEEN LACTATING BEEF AND DAIRY CATTLE Ian C . Hart, John A. Bines, Clive C . Belch and Alfred T. Cowie National
Institute for Research in Dairying,
Shinfield,
Reading,
RG2 9AT, Great Britain
(Received is final form March 19, 1975) Summary Hourly blood samples were taken throughout a 24h (metabolites) or 48h (hormones) period from three lactating beef (Hereford-cross) and three dairy (Friesian) cows which had been matched for age, stage of lactation (89-110 days) and diet (0 .55 kg hay + 4.95 kg concentrates, twice daily) . During the first 15 weeks of lactation the beef cows (B) gained weight and gave a poor yield of milk, whereas the dairy animals (D) lost weight but gave a good yield of milk . Significantly higher circulating levels of growth hormone (D-4 .2*0 .5 ; 8-1 .5*0 .2 ng/ml*SEM; P
Pergamoa Prese
HORMONE AND METABOLITE DIFFERENCES BETWEEN LACTATING BEEF AND DAIRY CATTLE Ian C . Hart, John A. Bines, Clive C . Belch and Alfred T. Cowie National
Institute for Research in Dairying,
Shinfield,
Reading,
RG2 9AT, Great Britain
(Received is final form March 19, 1975) Summary Hourly blood samples were taken throughout a 24h (metabolites) or 48h (hormones) period from three lactating beef (Hereford-cross) and three dairy (Friesian) cows which had been matched for age, stage of lactation (89-110 days) and diet (0 .55 kg hay + 4.95 kg concentrates, twice daily) . During the first 15 weeks of lactation the beef cows (B) gained weight and gave a poor yield of milk, whereas the dairy animals (D) lost weight but gave a good yield of milk . Significantly higher circulating levels of growth hormone (D-4 .2*0 .5 ; 8-1 .5*0 .2 ng/ml*SEM; P
