the purpose of this study was to investigate the effect of maternal inbreeding on incidence of twinning,dystocia and stillbirth in holstein cows of iran. calving records from march 2000 to april 2009 comprisingof 365,021 calvings on 153,802 cows from 86 dairy herds were used. the mean level of inbreeding was0.7%, less than 37% of all animals were inbred, and a small proportion (3.45%) of inbree...

This experiment was conducted to evaluate the association between risk factors and the risk of culling in Iranian Holstein cows. The data consisted of 329,772 lactation records obtained from the Animal Breeding Center of Iran (2003 - 2012) and logistic regression was applied to investigate the associations between the predictor and response variables. The response variable in this experiment wa...

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...

this study utilized daily records of 2000 egyptian holstein dairy cows. the productive, reproductive and economic data during a whole lactation season were recorded for healthy and mastitis cows. two risk factors for mastitis were included, parity and season of calving. mastitis cows had significant (p

The main objective of this study was to estimate the genetic parameters for multi-trait evaluation of birth weight (BW), gestation length (GL) and calving difficulty (CD) in first-parity Iranian Holstein dairy cattle. The data included 29,950 calving records collected during 1995 to 2014 by the Animal Breeding and Improvement Center of Iran. A threshold-linear sire-maternal grandsire model was ...

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 ...

Reference limits for metabolic profiles in Holstein late-pregnant heifers and dry cows were determined considering the effects of parity, days relative to calving, and season. Blood samples were collected from 104 pregnant heifers and 186 dry cows (68 primiparous and 118 pluriparous) from 60 to 10 d before the expected calving date in 31 dairy farms in northeastern Italy. Sampling was performed...

This experiment was conducted to determine the association between several risk factors which may affect culling of the Iranian Holstein cows. The data consisted of 329,772 lactation records collected by the Animal Breeding Center of Iran (2003 to 2012).The logistic regression was applied to investigate the associations between the response variable, the risk of culling, and predictor variables...

the aim of the present study was to estimate the genetic parameters and genetic trends of somatic cell score (scs) in the first 3 lactations of iranian holstein cows by random regression (rr) animal model by using restricted maximum likelihood (reml) method. the data set used in this analysis included observations of 340318 test-day records of 41526 cows in 288 herds; 89969 test-day of 11750 co...

this study was performed to investigate the incidence of abortion based on different definitions and, the effect of climate and herd size on abortion as well as its phenotypic trend. using calving records collected from 16 dairy herds from years 2004 through 2014. incidence rate and analysis of affecting factors on abortion were done using the freq and genmod procedures of sas software, respect...