AIM The present investigation was undertaken to study the reproduction performance and effect of non-genetic factors on reproduction performance of Jersey crossbred cows. MATERIALS AND METHODS Data on 355 Jersey crossbred cattle maintained at the Post-graduate Research Institute in Animal Sciences, Kattupakkam, Tamil Nadu, distributed over 30 years (1985 to 2014). The effect of various non-ge...

the present study aimed to estimate the effects of parity, calving season and year of calving on the prevalence of subclinical mastitis in holstein cows. a total of 2682 records from 869 holstein cows in a large dairy farm (azarbaijan province, iran), respecting the period from 2006 to 2009, were collected. data was analyzed using proc mixed of sas software by mivque method. subclinical mastiti...

Calving records collected between 2000 and 2008 at the Gudmundsen Sandhills Laboratory, Whitman, NE, were used to determine the effect of estrous synchronization on calving distribution and the impact of time of calving on carcass characteristics. Calves born between 2000 and 2006 resulted from non-synchronized 60 d breeding seasons between 1999 and 2005 (n = 2075). Calves born in 2007 and 2008...

Long breeding seasons result in long calving seasons. This results in calvings distributed through a range of environmental and nutritional conditions and a disparity in calf maturity at any planned weaning time. It also results in cows entering their period of maximal nutritional requirements over the same range of environmental conditions. Attempts to increase cow and calf productivity often ...

Fertility and reproductive performance of Landim and Africander females were compared using data collected from 1968 to 1981 at the Chobela Research Station in Mozambique. Breeds were managed together and grouped by age and sex, except when separated for breeding. Traits were relative fertility (probability of fertile females calving from the first breeding season), age at first calving, first ...

In a 7-year longitudinal study 292 Bovelder beef cows in a restricted breeding system in South Africa were observed from 1 to 2 days before their first breeding season, when reproductive tract scoring (RTS, scored from 1 to 5) was performed, until weaning their 5th calves. The objective was to determine whether pre-breeding RTS in heifers is a valid tool to predict long-term reproductive perfor...

Two bioeconomic computer models were used to evaluate calving seasons in combination with calf marketing strategies for a range-based cow-calf enterprise in the Northern Great Plains. Calving seasons studied were spring (SP, calving beginning March 15 and weaning October 31), spring with calf mortality increased by 5% (SP-IM), summer (SU, calving beginning May 15 and weaning December 31), summe...

The effects of non-genetic factors (sex of calf, calf birth weight, age of cow, season of calving) affecting gestation length (GL) and open days period (OP) in the Ngaoundere Gudali cattle of the Adamawa (Cameroon) was investigated. Mean GL was 293.4 ± 0.4 d. Sex of the calf significantly (P< 0.05) affected GL, with male calves being carried in utero approximately 3 days longer than the females...

AIM The objective of this study was to investigate the effect of genetic and non-genetic factors and estimate the genetic parameter for gestation length (GL) of Jersey crossbred cattle. MATERIALS AND METHODS The data included the 986 parturition records on Jersey crossbred cattle maintained at the Eastern Regional Station of ICAR-National Dairy Research Institute, Kalyani, West Bengal, India ...

Monthly estimates of 24-h milk yield were obtained on 160 spring-calving and 153 fall-calving crossbred cows containing various proportions (0, 1/4 or 1/2) of Brahman breeding, all bred to Limousin sires. Milk production was measured using weigh-suckle-weigh procedures. Interactions between crossbred group and season of calving were not significant. Across seasons, milk production rarely was af...