نتایج جستجو برای: cattle breeding
تعداد نتایج: 104336 فیلتر نتایج به سال:
McKenzie’s laboratory (U. MO; 1930s) described the estrous cycle of domestic animals. Brownell (Cornell; 1936) reported AI and bull bred pregnancy rates were similar. Between 1938 (first, EJ Perry, NJ) and 1940, 54 AI organizations in 21 states were formed. Ulberg, Christian and Casida (1951) controlled time of ovulation in cows with progesterone (P) injected daily. Trimberger and Hansel (1955)...
the objective of the present study was to determine the grades of nonspecific bacterial infection of genitalia of repeat breeding cattle by a simple and rapid test under field condition. for this purpose, a total of 100 crossbred jersey cows comprising of 80 repeat breeding animals presented for treatment and 20 normal cyclic (control group) animals presented for artificial insemination at thei...
We reportedhere data from a productivity veterinary service that was participatory planned and delivered on farms at the Kanihari Union belongs to Mymensingh District of Bangladesh. We used a set of five forms and a breeding calendar on farm visit once in a month to guide service delivery and acquisition of data and to keep the records on general cattle health, reproduction, udder health and fe...
Background Tree breeding is logistically complex and expensive, and breeders have long sought to use molecular markers to accelerate breeding. A candidate gene approach based on testing for association between the presence of DNA sequence variation in or near candidate genes, and phenotypic variation in a population has long been explored [1,2]. However, using candidate gene approach (QTLs) has...
In the present study, 12 Hereford bulls approximately 22.5 mo of age were individually introduced to a restrained nonestrous stimulus female for 15 to 30 min under four treatment conditions: (1) without prior sexual stimulation and visually isolated from male conspecifics (control), (2) being watched by another male during matings, (3) after observing the copulatory activities of another male a...
The current review focuses on characterization and conservation efforts vital for the development of breeding programmes for indigenous beef cattle genetic resources in Southern Africa. Indigenous African cattle breeds were identified and characterized using information from refereed journals, conference papers and research reports. Results of this current review reviewed that smallholder beef ...
In 1995, the multiple-trait across country genetic evaluation procedure replaced regression-based conversion equations as the preferred method for international genetic comparisons of dairy bulls. In the present study, February 1999 estimated breeding values of 632 foreign Holstein bulls that were used in Canada, Germany, Italy, The Netherlands, Sweden, and the US were compared with January 199...
The purpose of this investigation was to compare accuracy and precision of variance components and breeding values for international genetic evaluations based on national breeding values or animal performance records. A conventional progeny test scheme was simulated for 3 countries. True breeding values and observations were generated specific to production environments. Two production environm...
The present study was conducted with an objective of establishing a relationship between various routine semen evaluation parameters. Work was conducted at Sperm Station Palampur, Himachal Pradesh, on the semen from five Jersey X local hill cattle crossbred breeding bulls. A total of 40 ejaculates (8 from each bull), were analysed at five different stages of processing namely post dilution, pos...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید