A total of 248,230 first parity records of Holstein cows calving from 1987 to 1994, daughters of 588 sires in 3,042 herds were used to evaluate genotype by environment interactions in mature equivalent milk yield (MEM), lactation mean ...
It is also important to note that the phenotypic association between milk production and fertility/health varies from herd to herd (Windig et al., 2005). These authors found that, within farms with a high average production per cow, ...
When too large a proporAnimals such as these must tion of cows are culled for inferbe culled from the herd — a direct ... when milk yield is low ; from higher semen costs because more units of semen must be used to obtain each pregnancy ...
High merit cows had significantly greater (P
In herds with both a low average production and a low fertility of the cows there was no association between milk yield and SCC-peaks. Thus a higher production does not always increase the incidence of mastitis.
Under- milk yield , estimated as about 40 % in the standing the causes of early embryonic past 20 years in the USA ... herd fertility was high , with calving farm mammals . rates to first service between 60 and 69 % ; in the 1980s ...
This book provides a detailed review of current research on key components and quality traits of milk as well as ways of measuring milk quality.
Improve health status of the herd by addressing internal parasites that affect efficiency. Addresses high morbidity, low milk production and milk wastage in dairy systems Improve production and reproductive traits.