Merit of service sires for Holstein cows designated as genetically elite for yield in January 1990 was calculated to determine the contribution of these cows to genetic progress. Service sires were determined from sires of registered female progeny because male progeny were selectively registered. Primary data were 1295 elite cows (top 1%) that had a daughter produced from a mating in the 6 mo ...

A survey was conducted to quantify incidence of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls selling at auction during 2 seasons in 2008. Twenty-three BQA-related traits were evaluated by 9 trained personnel during sales at 10 livestock auction markets in Idaho (n = 5; beef and dairy), California, (n = 4; dairy only), and Utah (n = 1; beef and dairy). Ove...

Brahman preimplantation embryos are less affected by exposure to heat shock than Holstein embryos. Two experiments were conducted to test whether the ability of Brahman embryos to resist the deleterious effects of heat shock was a result of the genetic and cellular contributions from the oocyte, spermatozoa, or a combination of both. In the first experiment, Brahman and Holstein oocytes were co...

There is a paucity of data on the beef production potential of Norwegian Red (NOR) compared with 'modern' Holstein-Friesian (HF) cattle. The present study used a total of 64 bulls in a 2 × 2 factorial design study encompassing two breeds (HF and NOR) and two slaughter ages (485; E, and 610; L, days). The mean initial age and live weight of the HF bulls were 179 (s.d. 47.1) days and 203 (s.d. 64...

Two experiments were conducted to determine the effect of gonadal hormones on LH release by successive injections of Gonadotropin Releasing Hormone (GnRH). In the first experiment 1 month-old Holstein bulls were used. Bulls were assigned to be: 1) left intact (n=5), 2) castrated (n=6), or 3) castrated and given 10 mg testosterone thrice daily for 15 days (n=4). All animals received three intram...

In 1995, the multiple-trait across country genetic evaluation procedure replaced regression-based conversion equations as the preferred method for international genetic comparisons of dairy bulls. In the present study, February 1999 estimated breeding values of 632 foreign Holstein bulls that were used in Canada, Germany, Italy, The Netherlands, Sweden, and the US were compared with January 199...

Sequence variations in the bovine growth hormone (GH) gene were investigated by single strand conformation polymorphism (SSCP) analysis of seven amplified fragments covering almost the entire gene (2.7 kb). SSCPs were detected in four of these fragments and a total of six polymorphisms were found in a sample of 128 Holstein bulls. Two polymorphisms, a T-->C transition in the third intron (desig...

Genetic trend for milk yield in the artificially sired Holstein population in the northeastern United States was estimated from solutions for simultaneous genetic evaluations of bulls and cows for an animal model using mixed model equations and including all known relationships among the population by years of birth of 1960 to 1980 (1978 for bulls). First lactation milk records of 1,074,971 art...

Examination of the existence of pleiotropy or linkage of bovine leukocyte adhesion deficiency with other traits and of the impact of removal of the recessive, undesirable allele on genetic progress for those traits has been limited. Frequency of carriers among 6400 Holstein bulls tested was 8.2%; however, reporting was incomplete, and, therefore, the estimate of carrier frequency was biased dow...

AIM The present study was carried out on semen ejaculates of 15 Karan Fries (KF) bulls maintained at Artificial Breeding Research Centre, National Dairy Research Institute, Karnal, India with an objective to evaluate the relationship between the conventional and fluorescent based semen quality analysis of the bulls. MATERIALS AND METHODS A total of 96 ejaculates were collected from 15 KF (Hol...