bovine immunodeficiency virus is a lentivirus which can cause varieties of infectious complications and induce remarkable losses to dairy industry. considering to the probability of worldwide distribution of the biv infection, this study was conducted for the first time in iran to determine of the status of biv infection in the holstein cattle and evaluate the associated findings. according to ...

First-growth orchardgrass and alfalfa were harvested at two stages of maturity, treated with formic acid plus formaldehyde, and ensiled as direct-cut silage during 1978 and 1979. The 1978 silages were fed to eight yearling Holstein heifers (average BW 273 kg), and the 1979 silages were fed to eight yearling Holstein steers (average BW 264 kg) in replicated 4 x 4 Latin square experiments to meas...

Previously, our laboratory showed that Holstein cattle experimentally infected with Neospora caninum develop parasite-specific CD4+ cytotoxic T lymphocytes (CTL) that lyse infected, autologous target cells through a perforin-granzyme pathway. To identify specific parasite antigens inducing bovine CTL and helper T-lymphocyte responses for vaccine development against bovine neosporosis, the tachy...

using monthly test day records the genetic parameters of iranian holstein cattle in first lactation were studied. data of 277400 test-day milk records from 65320 cows and 2210 sires were analyzed by an animal random regression model using restricted maximum likelihood methodology. the model included herd-test-date, interaction between year-season of calving, days in milk (linear and quadratic) ...

Livestock species can be affected by different types of genetic defects. Recently, we are faced with genetic defects in dairy cattle such as bovine leukocyte adhesion deficiency (BLAD) and complex vertebral malformation (CVM) both are autosomal recessive defects leads to an inherited lethal disease in Holstein breed. BLAD is caused by a deficiency in leukocyte surface glycoproteins known as int...

Two studies using beef and calf-fed Holstein cattle were conducted to determine the effect of zilpaterol hydrochloride (ZH) supplementation on the color of strip loin steaks packaged in traditional and modified-atmosphere packaging. Select (USDA) strip loins were obtained from the carcasses of beef (n = 118) or calf-fed Holstein (n = 132) cattle fed ZH (6.8 g/ton on a 90% DM basis) for the last...

embryo transfer (et) in holstein dairy cattle became an important commercial enterprise after the introduction of non-surgical recovery technique. embryo transfer could increase the reproductive rate of genetically superior cows. the objectives of the present study were to evaluate the use of et in iranian holstein dairy cattle to increase selection intensity on the dam side, economically; esti...

Our objective was to determine the effect of repeated use of implants on feedlot performance and carcass characteristics of Holstein cattle. Holstein steers (n = 128) weighing an average of 211 kg were blocked by weight and randomly assigned to 16 pens. At the start of the trial (d 0), pens were assigned to one of four treatments: 1) nonimplanted control (C); 2) implant on d 0, 112, and 224 (T3...

Economic weights (EW) for the Slovak dairy production system were calculated in Holstein, Slovak Simmental, and Slovak Pinzgau breeds under a direct support regime using a bio-economic approach. EW were calculated for three scenarios (A: without agricultural subsidies; B: agricultural subsidies included in revenues and C: agricultural subsidies included in feeding costs). Quota-free milk produc...

We investigated the associations between SLC11A1 polymorphisms and susceptibility to tuberculosis (TB) in Chinese Holstein cattle, using a case-control study of 136 animals that had positive reactions to TB tests and showed symptoms and 96 animals that had negative reactions to tests and showed no symptoms. Polymerase chain reaction (PCR) sequencing and the restriction fragment length polymorph...