The study was carried out at Agarfa ATVET College dairy farm to evaluate the reproductive performance of Holstein Friesian× Arsi and Holstein Friesian ×Boran cattle. For the study, records compiled from 1983 to 2012 at the Agarfa dairy farm were used as original data. The effects of breed, bloodlines, season and parity on the reproductive traits were evaluated. Data were analyzed using the gene...

in the present study, to estimate genetic parameters and genetic and phenotypic trends in holstein dairy cows in the north of iran, the records from first lactation of 11398 collected from 1989 to 2006 were used. records were collected from 290 herds. productive traits were 305 day-2x adjusted milk and fat yield and reproductive traits were age at first calving, calving interval and dry days. g...

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...

The objective of the present retrospective cross-sectional study was to estimate prevalence postpartum clinical diseases (PPCDs) dairy cows reared under existing management conditions smallholder zero-grazing farming in Gasabo district, Rwanda. data PPCDs were collected retrospectively from 250 which calved for period 01 November 2019 29 February 2020. diagnosed hour calving until 40 days by an...

productive and reproductive traits have great importance in international dairy cattle breeding objectives. production, reproduction (days open and calving interval) and pedigree data of iranian holstein dairy cattles were collected between 2002 and 2012 from 47 herds in isfahan province. the data set consisted of 30179 records from 18837 registered iranianholstein dairy cattles. single trait r...

The objective of this study was to evaluate calving intervals and repeatability of calving intervals of young beef cows when breeding seasons were initiated immediately after calving. Average calving date at 2, 3, and 4 yr of age was recorded, and duration of calving interval between the first and second and second and third parities was compared in 178 crossbred beef cows calving between 1981 ...

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...

This study was designed to investigate causes of culling in industrial dairy herds in Fars province and to describe the pattern of reason-specific culling with respect to age of animal and interval from calving to culling. A total number of 9 dairy herds were selected for the study and information about culling reasons, birth date, last calving date and culling date was collected for culled cow...

The association of birth type (single vs. double) and pregnancy type (single vs. double) with lactation performance and lactation curve was investigated in Holstein cows in Iran. Data of 243298 lactations on 138021 cows in 261 herds collected during January 2000 to December 2012 were used. The average twinning rate was 3.64% and ranged from 1.44% (primiparous) to 5.41% (multiparous). Factors as...