ABSTRACT
Friesian cattle are the leading dairy strain in the world. The strain originated in Friesia, a very small province of northern Europe, which is divided into two parts belonging to Netherlands and the Federal Republic of Germany. The good milk performance of American Holstem-Friesian cattle has boosted their popularity among all stock farmers in the developed world and has intensified the importation of strain semen for crossing with other Black-and-white strains. The comparison of Friesian strains is made between the first crosses (F1) on the Polish Friesian cows inseminated with semen provided by the participating countries. The F1 groups' milk production under intensive feeding conditions was compared with a control group of 400 randomly chosen heifers, i.e., 40 per each tested strain. The strains of Holstein-Friesian type showed the highest milk yields and lowest fat contents both under field and intensive feeding conditions.
