Multiparous, spring-calving beef cows (n = 250) were used to determine whether large changes in body energy reserves during mid- to late gestation influenced subsequent reproductive performance of cows calving in moderate body condition. In three states, cows were blocked by BW and body condition score (BCS; 1 = emaciated to 9 = obese) then allotted to receive either a high or low plane of nutr...

Stayability to consecutive calvings was selected as a measure of cow longevity in the Canadian Simmental population. Calving performance data on 188,579 cows and culling information from the Total Herd Reporting System were used to determine whether a cow stayed in a herd for her second and later (up to the eighth) calvings, given that she had calved as 2 yr old. Binary records (n = 1,164,319) ...

In most studies on beef cattle longevity, only the cows reaching a given number of calvings by a specific age are considered in the analyses. With the aim of evaluating all cows with productive life in herds, taking into consideration the different forms of management on each farm, it was proposed to measure cow longevity from age at last calving (ALC), that is, the most recent calving register...

The aim of this study was to evaluate the effect calving season on postpartum changes certain blood metabolites and minerals body condition score evaluation (BCS) in Montbeliard dairy cows reared under semi-arid conditions. Blood samples were collected from 74 clinically healthy 10 semi-intensive Algerian herds once month during a whole year. Animals grouped according occurrence their four diff...

to investigate the effects of certain factors on the rate of retained placenta, 2844 calving records from 1288 holstein cows in a herd were used. these cows calved during year period of 2001 to 2007. a generalized statistical linear model was applied to analyze the data. logistic regression model was applied as the statistical model. in the model, fixed effects of year, season (warm or cold) an...

Objective-To assess the effect of lameness on culling of dairy cows in Tehran province. Design- Historical cohort study. Study population and procedures- 7067 first- and second-parity Holstein dairy cows that calved from March, 21 2007 to March, 20 2008 were until next calving or culling. Logistic regression was conducted data. Results-The overall lactational culling rate for eligible cows i...

Two trials were conducted to evaluate one trial, pregnancy first 21 d and total pregnancy in effects of Synovex C@ implants on replacement heifers, 63-d breeding season were decreased ( P = . 0 5 ) by given at two different ages. Crossbred heifer calves ( n implanting at 6 mo. At subsequent calving, an = 370) were allotted to four treatments: 1) noninteraction existed between the effects of the...

A survey of management practices in 309 Irish dairy herds was used to identify risk factors for the presence of antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in extensively managed unvaccinated dairy herds. A previous study documented a herd-level seroprevalence in bulk milk of 49%, 19% and 86% for Salmonella, Neospora caninum and leptospira interrogans se...