Random samples of cryopreserved, milk-extended semen, collected from 20 Holstein bulls at about 14 mo of age (young) and again at about 4 yr of age (mature), were evaluated at thawing and during 3-h incubation to compare semen quality of young versus mature bulls. Evaluation by differential interference contrast microscopy showed greater proportions of cytoplasmic droplets in semen from young v...

Origanum vulgare contains high levels of phenolic compounds such as gallic acid and polyphenols such as rosmarinic acid and quercetin. The purpose of this study was to investigate the effects of Origanum vulgare extract, as a natural antioxidant, on freezing-thawing semen quality in Holstein bulls. Three Holstein bulls (5-6 years old, mean live weight 800 kg) were used for semen collection twic...

Bone morphogenetic protein 15 (BMP-15) expression has been detected in the testis, but its roles in this organ has not been well elucidated. We evaluated polymorphisms of the BMP-15 gene by PCR-SSCP and PCR-RFLP in 212 Chinese Holstein bulls, and investigated possible associations with sperm quality traits, including semen volume per ejaculate, sperm density, fresh sperm motility, thawed sperm ...

AIM The present study compared the testicular cytology and histology between crossbred (Holstein-Friesian [HF] × Tharparkar) and purebred (HF and Tharparkar) bulls to find out differences if any. MATERIALS AND METHODS Four peripubertal bulls from each breed were utilized for the study. Through percutaneous needle aspiration biopsy, Sertoli and spermatogenic cells were extracted, and morphomet...

International Bull Evaluation Service evaluations from May 2005 were examined for country bias by comparing Holstein full-brother families. Countries with > or =25 bulls in multicountry full-brother families were included. The model fit evaluations of US estimated breeding values (EBV) by absorbing full-brother family and producing solutions for country of brothers. For yield and somatic cell s...

Forty-eight bulls (335 +/- 8.6 kg of initial BW) were randomly assigned to 4 glycerin levels (0, 4, 8, and 12% of concentrate DM) with the objective of evaluating the effects of glycerin supplementation on performance, ruminal fermentation, metabolism, and carcass and meat quality in Holstein bulls fed high-concentrate diets. Concentrates were formulated to be isonitrogenous and isocaloric (ass...

The objective of this study was to evaluate the quality of thawed semen of Holstein bull by computer assisted sperm analysis (CASA). A total sample of 40 straws imported from USA (total bulls = 4; 5 ejaculates per bull; 2 straws per ejaculate) was analysed by CASA using an IVOS. Semen motility was evaluated for kinetics parameters after thawing. The percentage of total mobile spermatozoa (%TMOB...

International genetic evaluations from August 1995 and February 1996 for Holstein bulls from Canada, France, Germany, Italy, The Netherlands, and the US were evaluated for consistency across time. Mean evaluations, expressed on a US basis, were unchanged for US bulls; evaluations for bulls from France, Germany, Italy, and The Netherlands increased about 14 kg for milk and 0.4 kg for fat and pro...

this study was performed to determine the effect of copper on growth performance, blood metabolites and claw health in young holstein bulls in a humid area in north of iran. one hundred and two young holstein bulls (initial body weight= 377.3±17.1 kg) were randomly allocated to two treatments in a completely randomized design for 56 days. the treatment groups received: (1) the basal diet of no ...

An experiment was conducted to test whether the magnitude of effects of heat shock on spermatozoal function were less for thermotolerant breeds (Brahman and other breeds with Brahman influence) than for breeds that evolved in northern Europe (Angus and Holstein). Frozen spermatozoa were thawed, purified by Percoll gradient centrifugation and incubated at 38.5, 41, or 42 degrees C for 4 h. Sperm...