The importance of lameness in primiparous dairy heifers is increasingly recognised. Although it is accepted that clinical lameness in any lactation increases the risk of future lameness, the impact of foot lesions during the first lactation on long-term lameness risk is less clear. This retrospective cohort study aimed to investigate the impacts of foot lesions occurring around the time of firs...

the objective of this study was to estimates the genetic and environmental components for the lactation curve parameters, milk yield, age at first calving (afc), calving interval (ci) and somatic cell count (scc) in iranian holstein cows. the dataset consisted of 210625 test day records from 25883 cows with milk yield in the first parity recorded from july 2002 to september 2007 in a total of 9...

Determining a calving law valid for all glaciological and environmental regimes has proven to be a difficult problem in glaciology. For this reason, most models of the calving process are semiempirical, with little connection to the underlying fracture processes. In this study, I introduce methods rooted in statistical physics to show how calving laws, valid for any glaciological domain, can em...

Fifty one dairy buffaloes in their last two months of gestation were selected at seven peri-urban commercial farms located within a radius of 70km around Peshawar. These animals were monitored from parturition until 150 days post-partum. After parturition, rectal examination of reproductive organs was carried out. Estrus detection was made through visual signs and use of intact bulls. Milk samp...

Data on productive and reproductive performance of cows in dual-purpose herds were analyzed to determine the effect of some environmental and genetic factors on saleable milk yield (SMY), lactation length (LL), daily saleable milk per lactation (DMYL), calving interval (CI), and daily saleable milk per calving interval (MYCI) in dual-purpose herds in Yucatan, Mexico. Repeatabilities (re) for th...

Calving traits for frequently used dairy breeds and crossbreeds were investigated using calving records collected in Australia over a period of 18 years. Dystocia (calving difficulty) was highest for heifers calving to Holstein-Friesian bulls, and Jersey calves caused the least dystocia. Incidence of dystocia in Holsteins was influenced by the season (gestation lengths were longer in winter, re...

to describe proportion and pattern of culling in commercial dairy herds of khorasan razavi province, this survey was carried out from 21st march 2008 to 20th march 2009 in 15 industrialized dairy herds. for each culled cow data related to parity at culling, last calving to culling interval and primary reason for culling were recorded. annual herd exit rate was 20.9%. out of a total of 652 culle...

The effect of calving ease on the fertility and production performance of both dam and calf was studied in approximately 50,000 and 10,000 UK Holstein-Friesian heifers and heifer calves, respectively. The first objective of this study was to estimate the effect of a difficult calving on the subsequent first-lactation milk production by estimating lactation curves using cubic splines. This metho...

A total of 198 cows were randomly assigned to treatment with a single intramuscular injection of 10 ml of a preparation containing vitamin E and selenium or placebo 3 wk before expected parturition. Incidence of retained fetal membranes was 3.0% for the treated group and 10.1% for the control group (P=0.06). Administration of MU-SE also increased the percentage of cows pregnant to the first ser...