Some hormonal characteristics of high and low yielding Holstein cows and water buffaloes located in temperate and subtropical environments.
The present study was carried out on 18 Holstein cows located in Missouri, USA (Holstein-M), 32 Holstein cows located in Egypt (Holstein-E), and 32 Egyptian water buffaloes (Buffaloes-E). Half of each group was high yielders and the other half was low with a mean daily milk yield of 32.2 and 18.6 kg for Holstein-M, 14.6 and 6.7 kg for Holstein-E, and 7.2 and 1.8 kg for Buffaloes-E, respectively. Blood samples were collected after the morning milking. Mean plasma thyroxine and triiodothyronine concentrations were significantly higher in Holstein-M than those in Holstein-E or Buffaloes-E. In all animal groups, the high yielders generally had lower plasma thyroxine and antidiuretic hormone but higher plasma triiodothyronine contents than the low yielders. Buffaloes had lower plasma cortisol and 9-fold higher plasma antidiuretic hormone as compared with the two Holstein groups.
el-Nouty
F D
FD
Department of Animal Production, Faculty of Agriculture, Alexandria University, Egypt.
Johnson
H D
HD
Kamal
T H
TH
Hassan
G A
GA
Salem
M H
MH
D000704:Analysis of Variance; D000818:Animals; D002020:Buffaloes / Q000097:blood*; D002417:Cattle / Q000097:blood*; D004534:Egypt; D005260:Female; D006728:Hormones / Q000097:blood*; D006854:Hydrocortisone / Q000097:blood; D007774:Lactation / Q000097:blood*; D008923:Missouri; D011247:Pregnancy; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D014667:Vasopressins / Q000097:blood
D006728:Hormones; D014284:Triiodothyronine; D014667:Vasopressins; D013974:Thyroxine; D006854:Hydrocortisone