A 3-yr study was conducted with heifers (n = 170) whose dams were used in a 2 x 2 factorial arrangement of treatments to determine the effects of late gestation (LG) or early lactation (EL) dam nutrition on subsequent heifer growth and reproduction. In LG, cows received 0.45 kg/d of a 42% CP supplement (PS) or no supplement (NS) while grazing dormant Sandhills range. During EL, cows from each l...

Dried distillers grains plus solubles (DDGS) contain fat and rumen undegradable intake protein, both of which have been shown to increase reproductive performance in heifers. The mechanisms leading to enhanced reproduction have not been fully defined. The objectives of this research were to evaluate effects of DDGS in late gestation heifer diets on animal and reproductive performance and on blo...

OBJECTIVE The effects of the pre- and postpartum supplementation of cows with Se on their plasma P4 concentrations after calving were investigated. METHODS Thirty-four Holstein cows were used to investigate the effects of dietary selenium supplementation on the postpartum recovery of the luteal function in cows. Selenium-rich yeast (containing 300 ppm selenium) was mixed with total mixed rati...

Abstract We hypothesized that late gestational nutrient restriction (NR) would decrease organ mass in neonatal calves. Fall-calving crossbred beef heifers (BW: 466 ± 30 [SD] kg; BCS: 5.4 0.5) bred to a single sire were individually fed 100% (control; n = 10) or 70% (nutrient restricted; NR; 12) of NASEM metabolizable energy and protein requirements for maintenance, pregnancy, growth from d 160 ...

There is considerable concern about the consequences on fitness-related traits of using narrow breeding objectives for production traits. The aim of this study was to assess the potential consequences of selection for growth in French beef cattle breeds by estimating genetic correlations between growth, reproduction, calving and suckling traits of Charolais, Limousin and Blonde d’Aquitaine heif...

The objective of this study was to investigate the effect of birth weight (BW) on future milk production and reproductive performance in Iranian Holstein cattle. Records of Holstein cows between 1967 and 2010 were obtained from the Animal Breeding Center of Iran. Birth weights within each herd were grouped into five categories based on the standard normal distribution curves (z ≤-0.8416, -0.841...

Data on 368 birth records of Swedish Red and White cattle herd raised organically at Dogan Organic Dairy Cattle Farm for a period of 2006 and 2009 (4 years) were used to estimate the effects of different environmental factors on birth weight. Additionally, a comparison of four methods for variance component estimation to compute heritability of birth weight was performed using ML (Maximum likel...

Oestrus and ovarian activity were studied in a group of crossbred SahiwalShorthorn beef cows over four lactation periods of varying length throughout different seasons of the year. In the first lactation, cows were in poor condition (body weight 303 kg) and the mean interval from calving to first oestrus was 2202 16 days. Five COWS were still anoestrus 18 months after calving and were culled. T...

The objective of the study was to evaluate the effect of energy contents in a dry period diets in "7+1" feeding strategy of dry cow including 7 weeks of the dry period (far-off) and 1 week of a close-up period, on colostrum quality and the immune status of calves. Forty Holstein multiparous cows were dried at 56d before the expected date of calving and were assigned to the higher energy diet gr...

There is limited information on the value of antibiotic therapy for mastitis in beef cows. Effects of antibiotic treatment at weaning and the subsequent calving on calf weaning weight, milk somatic cell counts, milk components, and intramammary infection were studied in beef cows. Additionally, effects of number of infected mammary quarters, number of dry mammary quarters, type of intramammary ...