this experiment was conducted to evaluate reproductive indices and provide appropriate solutions to improve the reproductive efficiency of dairy cattle in kermanshah province. with reference to forty-eight dairy industrial herds available at different cities of the province, a questionnaire containing quantitative measures were completed to assessing the reproductive parameters of 5397 dairy co...

BACKGROUND Over two decades of observations in the field in South East Asia and Hawai'i suggest that majority of the commercial dairy herds are of black hair coat. Hence a simple study to determine the accuracy of the observation was conducted with two large dairy herds in Hawaii in the mid-1990s. METHODS A retrospective study on longevity of Holstein cattle in the tropics was conducted using...

A high incidence (about 70%) of alteration in endometrial epidermal growth factor (EGF) profile, i.e., loss of 2 peaks on days 2-4 and 13-14, has been linked to a reduced fertility in multiparous repeat breeder Holstein cows. However, the EGF profile in Holstein heifers and other breeds (types) of cattle has not been investigated. In study 1, EGF concentrations were determined using endometrial...

Bovine genital campylobacteriosis is one of the most economically important diseases of dairy cattleresulting in lowered fertility, embryo mortality and abortion, repeated returns to service, reduced pregnancyrates and extended calving intervals. While the occurrence of repeat breeding syndrome and abortions arereported from many Iranian dairy cattle farms, little information is available regar...

bovine genital campylobacteriosis is one of the most economically important diseases of dairy cattleresulting in lowered fertility, embryo mortality and abortion, repeated returns to service, reduced pregnancyrates and extended calving intervals. while the occurrence of repeat breeding syndrome and abortions arereported from many iranian dairy cattle farms, little information is available regar...

dairy cattle breeding programs have been based in the selection for traits related to milk production. in this research a data set of 63 herds of east azerbaijan province holstein cattle, collected during 2002-2013 by the iranian animal breeding center was used to estimate the repeatability and heritability of three traits of economic importance. genetic parameters for first three lactations of...

Crossbreeding is a popular tool for genetic improvement of pigs, beef cattle, and other livestock species, but its use in US dairy cattle has been limited for several reasons. The primary reason is the advantage of Holstein cows in milk volume, coupled with a milk pricing system that still tends to reward quantity, rather than quality, in many regions of the country (i.e., through volume premiu...

Excellent reviews of cattle breed comparisons or breed-cross comparisons have been previously reported by Franke (1980), Long (1980), and Marshall (1994). However, these reviews do not contain information on the calving ease, performance, carcass characteristics, or beef palatability of crossbred progeny of Holstein dams sired by different beef breeds. In many countries dairy females are common...

mastitis in cattle is a serious problem which causes considerable economic losses in the dairy cattle herds. the aim of this survey was to identify mycoflorain milk of healthy, clinical and subclinical mastitis of lactating holstein dairy cows. milk samples of 154 holstein dairy cows were collected from 10 dairy cattle herds in suburb of mashhad-iran. the treatment groups included 104 lactating...

mastitis is one of the most serious and costly diseases affecting dairy cattle production. in the present study, effects of a lactoferrin gene polymorphism (intron 6) on milk somatic cell count (scc) and subclinical mastitis was investigated in 121 holstein dairy cattle. two alleles of a and b and two genotypes of aa and ab were found in an ecori recognized single nucleotide polymorphism in int...