Purebred Holstein-Friesian cows are the main exotic breed used for milk production on large, medium, and small farms in Kenya. A study was undertaken on seven large-scale farms to investigate the genetic trends for milk production and fertility traits between 1986 and 1997 and the genetic relationships between the traits. This involved 3,185 records from 1,614 cows, the daughters of 253 sires. ...

The aim of this study was using Bayesian approach via Gibbs sampling (GS) for estimating genetic parameters of production, reproduction and health traits in Iranian Holstein cows. Data consisted of 320666 first- lactation records of Holstein cows from 7696 sires and 260302 dams collected by the animal breeding center of Iran from year 1991 to 2010. (Co) variance components were estimated using ...

Transfer of sufficient immunoglobulin G (IgG) to the neonatal calf via colostrum is vital to provide the calf with immunological protection and resistance against disease. The objective of the present study was to determine the factors associated with both colostral IgG concentration and colostral weight in Irish dairy cows. Fresh colostrum samples were collected from 704 dairy cows of varying ...

Submit Manuscript | http://medcraveonline.com Abbreviations: AAU: Addis Ababa University; AFC: Age at First Calving; AFS: Age at First Service; CFT: Complement Fixation Test; CI: Calving Interval; CVMA: College of Veterinary Medicine and Agriculture; NSC: Number of Services per Conception; PGF2α: Prostaglandin F2 Alpha; PPA: Post-Partum Anoestrus; RBPT: Rose Bengal Plate Test; RP: Retained Plac...

For lactating dairy cows, we need management tools, that are "clean, green and ethical", cost-effective and easy to use. Specific tools are needed for artificial insemination (AI) after oestrus detection within a few months of calving, and for managing the complex nutritional requirements of cows between successive calvings. Assessment of energy deficit by measurement of body condition score (B...

There are significant costs associated with reproductive inefficiency in pasture-based dairy herds. This study has quantified the economic effect of a number of key variables associated with reproductive inefficiency in a dairy herd and related them to 6-week calving rate for both cows and heifers. These variables include: increased culling costs, the effects of sub optimum calving dates, incre...

This study was carried out in a commercial herd from 2008 to 2012 in order to determine the most prevalent reasons for culling Holstein cows and to assess the effects of risk factors. Overall, 519 (28.2%) cows were culled for involuntary (98.8%) and voluntary (1.2%) reasons. The involuntary causes of culling were diseases (38.7%), reproduction problems (36.0%), udder disorders (7.7%), lameness ...

F OR profitable milk production the dairy cow must reproduce regularly. An interval of i~ to 13 months between calves usually is considered satisfactory. Cows calving every i~ months or less had higher yields per day for the interval between calves than did cows that required more than ~ months before reproducing in studies by Gaines and Palfrey (i931) and Chapman and Casida (I935). This observ...

Inheritance of economic traits was studied in Nili-Ravi dairy buffaloes through analysis of data comprising 5037 records of daughters of 79 sires. Data were collected from three large-sized state dairy farms. Heritability, genetic and phenotypic correlations of some indicator traits on important production and reproduction traits were worked out. Based upon analysis of records for first lactati...