Obtaining sexed sperm from previously frozen doses (reverse-sorted semen [RSS]) provides an important advantage because of the possibility of using the semen of bulls with desired genetic attributes that have died or have become infertile but from whom frozen semen is available. We report the efficiency of RSS on the pregnancy rate and birth rate of calves in a large-scale program using ovum pi...

This paper aimed at investigating the potential use of sperm DNA fragmentation (SDF) to improve the routine screening of infertility of Holstein bulls. Cryopreserved sperm samples from 201 Holstein bulls provided by an AI center were used in the analyses of SDF at 0 (SDF_0) and 6 (SDF_6) h of incubation at 37oC. A refi nement of the sperm chromatin dispersion test implemented in the Sperm-Halom...

average age distribution and generation interval were investigated in four different selection pathways. i.e., sire of future sires (ss), sire of future dams (sd), dam of future sires (ds) and dam of future dams (dd). young bulls pathway (yb) is also considered as a path that affects the generation interval in sd pathway when using progeny testing program. data were collected from animal breedi...

Abstract In the Sverdlovsk region, purebred bull producers of Holstein breed German, Danish and Canadian selection breeding stock domestic black-and-white Ural offspring were used for improvement. The was distinguished by high milk yield fat mass fraction protein in milk. 2002, type cattle officially registered region. This has significant differences from original rocks. purpose article is to ...

Based on standard histological methods and specific injection technique, the study demonstrates for the first time the blood vessel system of the scrotal integument.The latter is relatively thin and shows a thick underlying fascia, the tunica dartos. The vessel networks found in both structures are somewhat different from each other, i.e., the former displays the typical integumental vessel sch...

Estimated breeding values (EBVs) and genomic enhanced breeding values (GEBVs) for milk production of young genotyped Holstein bulls were predicted using a conventional BLUP - Animal Model, a method fitting regression coefficients for loci (RRBLUP), a method utilizing the realized genomic relationship matrix (GBLUP), by a single-step procedure (ssGBLUP) and by a one-step blending procedure. Info...

Multiple regression of genetic evaluations for milk yields of first lactations of 159 Holstein bulls on sire, dam, and maternal grandsire evaluations indicates that the weight for estimated transmitting ability of the dam calculated from the first record of the dam and first records of her herdmates is about as theoretically expected and is markedly superior both to estimated transmitting abili...

The aims of the present study were: (1) to determine the existence of sperm subpopulations with specific motility characteristics in fresh ejaculates from Holstein bulls, (2) to investigate the effects of semen cryopreservation and post-thaw incubation on the distribution of spermatozoa within the different subpopulations, and (3) to evaluate the existence of between-bull variation in the sperm...

Use of sexed semen for artificial insemination of US Holstein heifers (1.3 million breedings) and cows (10.8 million breedings) in Dairy Herd Improvement herds was characterized by breeding year, parity, service number, region, herd size, and herd milk yield. Sexed semen was used for 1.4, 9.5, and 17.8% of all reported breedings for 2006, 2007, and 2008, respectively, for heifers, and for 0.1, ...