ABSTRACT.
The problem of the content of chemical elements in the body of farm animals and in livestock products is extremely relevant. The analyzed parameters are the elemental composition of the blood serum of dairy cows
(n=90). Three different breeds of cows were studied (black-mottled, red steppe and Ayshir breeds), each of these breeds
is represented by different farms of the Orenburg region. The elemental status was assessed by studying the chemical
composition of blood serum by inductively coupled plasma mass spectrometry. Cows of the Ayshir breed had significantly higher serum calcium content relative to cows of black-mottled and red steppe breeds by 62.8% and 55.7%, potassium by 50% and 31%, magnesium by 63% and 30%, phosphorus by 85% and 5%, copper by 62% and 20.6%, iron
by 118% and 5%, iodine by 199% and 50%, zinc by 110% and 6%, respectively. Thus, after conducting a study among
the three breeds, it can be concluded that the Ayshire breed is characterized by higher values of a number of important
macro- and microelements. The data obtained by us demonstrate the features of the elemental status of bovine blood serum in three different breeds of dairy productivity, which can be used for an extended assessment of the elemental status of animals in order to further establish the norm values for each specific breed.
KEYWORDS: cattle, dairy cows, trace elements