Reproductive failure in inseminated cattle results from poor fertilization and embryo survival. Recent studies utilizing dairy and beef cattle indicate that fertilization rates are higher for nulliparous dairy and beef heifers and nonlactating beef cows than lactating beef and dairy cows and nonlactating dairy cows. Several factors affect fertilization rates, but the greatest impact was observe...

Facial eczema (FE) is a disease of grazing ruminants causedbyingestingsporesofthefungusPithomyces chartarum. The spores contain a toxic compound, sporidesmin, which causes liver injury, sensitivity to sunlight andreduced performance in susceptible dairy cattle. The extent of production losses is summarised. Research at Ruakura has demonstrated that the resistance of animals to FE is inherited, ...

Introduction Mycoplasmas are normal inhabitants of the upper respiratory airways, urinary and genital tracts, and the digestive system; however, they can become infectious and cause high impact diseases in dairy herds including mastitis and metritis. In dairy cattle, Mycoplasma bovis is the most commonly isolated mycoplasma species (spp.). This species is very invasive and capable of colonizing...

A total of 200 milk samples from cattle (n = 86) and buffalo (n = 114) were evaluated using milk ring test (MRT) and indirect enzyme-linked immunosorbent assay (i-ELISA). The overall prevalence was found to be 3% and 8.5% in cattle and buffaloes using MRT and i-ELISA, respectively. The prevalence was 4.6% and 1.7% in cattle and buffalo using MRT, respectively, while i-ELISA exhibited 20% and 0%...

Hemorrhagic bowel syndrome is a highly fatal intestinal disease of adult dairy cattle with uncertain cause. In a dairy herd in KhorasanRazavi province, Northeast of Iran, two cows showed depression, anorexia, decrease in milk production, ruminal hypomotility, bruxism and dehydration. At necropsy, massive hemorrhage and clot formation was observed within the jejunum and bacterial culture of the ...

Background: A. bovis and A. phagocytophilium are leukocytotropic agents of bovine anaplasmosis. They are obligate intracellular bacteria that can infect and cause Anaplasmosis in human and animals. Therefore, this study was carried out to detect A. bovis and A. phagocytophilum in naturally infected dairy cattle in Isfahan using molecular techniques. Materials and Methods: In this study a tot...

We investigated the effect of stage of pregnancy on estimates of breeding values for milk yield and milk persistency in Gyr and Holstein dairy cattle in Brazil. Test-day milk yield records were analyzed using random regression models with or without the effect of pregnancy. Models were compared using residual variances, heritabilities, rank correlations of estimated breeding values of bul...

The major problems for the dairy practices in the tropical country are low milk yield and short lactation period of either pure exotic or crossbred dairy cattle. Many factors affect milk production in dairy cattle in tropical areas including high environmental temperature and humidity, lower genetic potential for milk production in indigenous cattle and inadequate supply of food during the dry ...

the objective of this study was to evaluate the concentration of these acute phase proteins(serum amyloid a, milk amyloid a and serum haptoglobin) and alteration in hematological values in some inflammatory diseases in dairy cattle. fifty-six holstein dairy cows with some inflammatory diseases were used in this study including: subclinical mastitis, hematological infections (theileriosis and an...

The method of Israel and Weller (Estimation of candidate gene effects in dairy cattle populations. Journal of Dairy Science 1998, 81, 1653-1662) to estimate quantitative trait locus (QTL) effects when only a small fraction of the population was genotyped was investigated by simulation. The QTL effect was underestimated in all cases, but bias was greater for extreme allelic frequencies, and incr...