منابع مشابه
Spermatozoa Molecules in Relation to Bulls Fertility
Bull fertility may be defined as the process by which spermatozoa fertilize and activate the ovum and then support embryonic development. Bull fertility is a complex trait having relatively low heritability and plays a vital role for efficient production and reproduction of bovine. Various mechanisms involved in regulating bull fertility associated phenotype and reliable biomarkers are poorly d...
متن کاملTesticular function in bulls 10 weeks after unilateral vasectomy.
Five mature dairy bulls were killed 10 weeks after unilateral vasectomy. Testes on the vasectomized side weighed 67% of the contralateral controls (P<.O1) and contained only 34% as many spermatids as the control testes (P<.01). Since a previous report showed little or no change in spermatogenesis in younger bulls at 23 weeks after vasectomy, possibly vasectomy temporarily interrupts spermatogen...
متن کاملImmunohistochemical Localization of Ghrelin in Testicular Tissues of Holstein Bulls
Ghrelin, a 28-amino acid acylated peptide, was identified as the endogenous ligand for the growth hormone (GH) secretagogue receptor and its role in reproduction has recently been established. It is believed that the site of ghrelin expression in testes may indicate its role in local regulation. This study investigated the immunohistochemical (IHC) localization of ghrelin in Holstein bull testi...
متن کاملDetermining Reproductive Fertility in Herd Bulls
ity of a beef operation is the percentage of the calf crop weaned, which, in turn, is determined mainly by the number of cows bred during the breeding season. The herd bull influences overall herd fertility more than any other single animal. Because the bull also supplies half of the genetics to all of the calves he sires, bull selection can be the most powerful method of genetic improvement in...
متن کاملComparative endocrinology of testicular, adrenal and thyroid function in captive Asian and African elephant bulls.
Concentrations of serum testosterone, cortisol, thyroxine (free and total T4), triiodothyronine (free and total T3) and thyroid stimulating hormone (TSH) were measured to assess adrenal and thyroid function as they relate to testicular activity and musth in captive elephants. Blood samples were collected approximately weekly from Asian (n=8) and African (n=12) bulls at seven facilities for peri...
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: Bioscientifica Proceedings
سال: 2019
ISSN: 2515-0227
DOI: 10.1530/biosciprocs.8.017