Conception Rate, Growth, and Lactation of Dairy Heifers Treated with Recombinant Somatotropin
نویسندگان
چکیده
منابع مشابه
Utilization of sulfur and other mineral elements by growing dairy heifers treated with bovine somatotropin.
Apparent absorption and retention of Ca, P, Mg, K, Cu, Mn, Zn, and S were determined in Holstein heifers treated with recombinant bovine somatotropin (bST). Six heifers (initial BW averaged 104 kg) were assigned to various doses of bST in a 6 x 6 Latin square design with six consecutive 21-d periods. Treatments were daily i.m. injections of 0, 6.7, 33.3, 66.7, 100, or 200 micrograms of bST/kg o...
متن کاملGenetic parameters of a biological lactation model: early lactation and secretion rate traits of dairy heifers.
Early lactation parameters are difficult to estimate from commercial dairy records due to the small number of records available before the peak of production. A biological model of lactation was used with weekly milk records from a single Holstein herd to estimate these early lactation parameters and the secretion rate of milk from the average cell throughout lactation. A genetic analysis of th...
متن کاملBovine somatotropin and rumen-undegradable protein effects on skeletal growth in prepubertal dairy heifers.
The objectives of this study were to determine the effects of dietary rumen-undegradable protein (RUP) and bovine somatotropin (bST) during the period from weaning until puberty on body weight (BW) and skeletal growth rates and age at puberty. Fifty-one Holstein heifers at 90 d of age were randomly assigned to 4 treatment groups consisting of 0.1 mg/kg BW per day of bST and 2% added dietary RUP...
متن کاملPregnancy rate and first-service conception rate in Angus heifers.
The objective of this project was to determine the genetic control of conception rate, or pregnancy percentage in Angus beef heifers. Producers from 6 herds in 5 states provided 3,144 heifer records that included breeding dates, breeding contemporary groups, service sires, and pregnancy check information. Two hundred fourteen sires of the heifers were represented; with 104 sires having less tha...
متن کاملBiology of somatotropin in growth and lactation of domestic animals.
Impressive progress has been made during the past 15 years in our understanding of the biology of somatotropin (ST) in domestic animals. In part, this progress was sparked by advances in biotechnology that made feasible the production of large quantities of recombinant bovine ST (bST) and porcine ST (pST). The availability of recombinant bST and pST resulted in an exponential increase in invest...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1990
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(90)78648-1