materials and methods: a total of 285 commercial and traditional dairy products as well as 267 pasteurized and raw milk samples were collected during one year. the samples were studied by culturing and the positive-culture samples were investigated using pcr techniques. results: the results of culture showed that 52 (9.42%) and 28 (5.07%) of the total 552 milk and dairy samples were positive fo...

this experiment was aimed to study the association between the dgat1 k232a polymorphism and milk production traits and somatic cell score (scs) in iranian holstein dairy cows. the records of 408 animals from five dairy herds were randomly identified and then genomic dna was extracted from blood using the modified-salting method described by miller. rflp-pcr was performed to obtain all the polym...

This paper examines the cost efficiency of dairy farms in 2 important regions of commercial milk production in Poland (i.e., Wielkopolskie and Podlaskie). Both regions gained importance following the market-driven resource allocation mechanism adopted after Poland's transition to the market economy in 1989 and accession to the European Union (EU) in 2004. The elimination of the dairy quota syst...

The modern dairy cow has been selected over generations for high milk production, with many successful dairy operations averaging over 13,500 kg of milk per lactation cycle per cow. This amount of nutrient output in the form of milk components puts a tremendous amount of pressure on the metabolism of the dairy cow, especially during early lactation. In fact, it is common to all mammals, includi...

nutrition has a significant effect on reproduction and lactation in ruminant. supply of require nutrient of dairy cows and ewes in early lactation is the main challenges that will be considered, since in most cases the animals facing negative energy balance after calving and the beginning of the period of lactation. negative energy balance may sometimes result in reduced livestock production an...

A common perception is that pasture-based, low-input dairy systems characteristic of the 1940s were more conducive to environmental stewardship than modern milk production systems. The objective of this study was to compare the environmental impact of modern (2007) US dairy production with historical production practices as exemplified by the US dairy system in 1944. A deterministic model based...