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...

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...

For the current research the records of 62 farms in Isfahan province were available. To estimate genetic and phonotypic trends of reproductive traits such as age at first calving, calving interval, days open and number of insemination to conception rate the records of 63,866 cows including 167793 reproductive records were employed. Farms were covered by Vahdat industrial Agriculturists and Dair...

For the current research the records of 62 farms in Isfahan province were available. To estimate genetic and phonotypic trends of reproductive traits such as age at first calving, calving interval, days open and number of insemination to conception rate the records of 63,866 cows including 167793 reproductive records were employed. Farms were covered by Vahdat industrial Agriculturists and Dair...

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...

A total of 1385 lactation records of Tharparkar cattle collected from LRS Chandan, Jaisalmer spreading over a period of 33 years were utilized to assess the effects of period and season of birth/calving on age at first calving, calving interval and service period and also studied effect of parity on calving interval and service period. The least-squares means were 1821.86 ± 37.022 days, 414.16 ...

for the current research the records of 62 farms in isfahan province were available. to estimate genetic and phonotypic trends of reproductive traits such as age at first calving, calving interval, days open and number of insemination to conception rate the records of 63,866 cows including 167793 reproductive records were employed. farms were covered by vahdat industrial agriculturists and dair...

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...

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