title: Some hormonal characteristics of high and low yielding Holstein cows and water buffaloes located in temperate and subtropical environments.
abstract: 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.
authors.affiliation: Department of Animal Production, Faculty of Agriculture, Alexandria University, Egypt.
authors.forename: F D
authors.initials: FD
authors.lastname: el-Nouty
authors.forename: H D
authors.initials: HD
authors.lastname: Johnson
authors.forename: T H
authors.initials: TH
authors.lastname: Kamal
authors.forename: G A
authors.initials: GA
authors.lastname: Hassan
authors.forename: M H
authors.initials: MH
authors.lastname: Salem
mesh_terms: 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
chemical_list: D006728:Hormones; D014284:Triiodothyronine; D014667:Vasopressins; D013974:Thyroxine; D006854:Hydrocortisone