Mineral exchange in bullsproducers in the conditions of the Leningrad region

Abstract

 This work is devoted to the general monitoring of mineral exchange in Holstein bullsproducers (n = 50) of black-and-white color in the conditions of the Leningrad region. The mineral exchange of bulls was studied depending on the selection (American (n = 7), Russian (n = 11) and European (Netherlands) (n = 32)) in the age range from 2 to 5.5 years. Such parameters as calcium, phosphorus, magnesium, iron, alkaline phosphatase, copper and zinc were studied using a biochemical analyzer Chem Well 2902 (Awareness Technology, USA) and an atomic absorption spectrometer “Kvant-2A”. It was found that the studied indicators for the content of minerals in blood serum are mainly at the level of reference values. There are significant differences in the bulls of
Russian and European breeding (P < 0.001). Above the reference values  concentrations of phosphorus were noted in young bulls, magnesium in all age groups, which affected the ratio of changes in the ratio of calcium and phosphorus at a highly reliable level (P < 0.001). There was also a shortage of copper in bulls of Russian and European origin (9.52 mmol/l and 8.35 mmol/l versus 9.81 mmol/l and 19.888 mmol/l in the norm). A relatively low level was observed in bulls of younger age (up to 24 months — of 6.33 mmol/l), and a zinc surplus in adult bulls over 37 months — of 59.2–62.4 mmol/l against 53.05 mmol/l the norm. We believe that it is necessary to constantly monitor the mineral metabolism of breeding bulls, not only taking into account their origin and age, but also their individual condition.