Studies aimed to determine the usefulness of mineral mixture Bovifosfomag ® in bovine nutrition were carried out in southern Podlasie, Poland, over a period of two years. The criterion of its usefulness was the level of particular minerals measured in the hair of dairy cows. The concentrations of calcium, phosphorus and magnesium were measured by the ICP (Inductively Coupled Plasma) method using the ICP spectrometer Philips SC-PU 7000 attached to the Cetac U-5000 AT ultrasonic nebulizer. Hair samples were taken twice, 10-14 days before parturition and after the first month of lactation. Bovifosfomag ® mineral mixture, which had been developed on previous macromineral deficiency monitoring studies, in most cases improved the supply of minerals to cows in the surveyed farms. Hair of cows differed significantly in calcium, phosphorus and magnesium content. The reasons for this probably lay in the individual characteristics of the cows. Bovine coat hair proved useful in the diagnosis of mineral deficiencies and revealed a short supply in phosphorus and magnesium in the control group. The study of the mineral composition of hair partially confirmed previous trends in the patterns of mineral levels observed in blood serum. An increase in Ca, P and Mg in the hair of the animals fed the supplement was found.

Tenderness and marbling are polygenic characteristics that are important parameters of meat quality. In this study, we analyzed the genetic predisposition for both parameters in Beefmaster cattle. Tenderness was determined by the presence of calpastatin enzyme (an inhibitor of the post-mortem softening process of meat) alleles inherited by each animal, marbling was judged by the thyroglobulin gene, which encodes a precursor of the thyroid hormone that is a major regulator of fat metabolism and storage. One hundred forty five blood, semen or follicle samples from Beefmaster cattle were analyzed to generate a gene allele profile associated with tenderness and marbling. Of the animals, 43.4% showed gene predisposition for marbling, gene predisposition for tenderness was observed in 62.1%. The findings are intended to be incorporated into the decision making process of breeding programs to increase the number of animals with superior meat quality. The use of these markers could guide investment in better cattle offspring as complementary indicators of meat quality.

Studies were conducted on farm “A” located in east-central Poland to assess the mineral content in cows, taking into account individual links of the soil-feed-animal trophic chain. The mineral assessment included the determination of Na and K. Soil samples were taken once from the humus layer (that is at the depth of 0-15 cm) of pastures and arable fields in mid-growing season by means of a soil sampling stick. Feed samples were taken regularly when the feeds were included in rations (all year round), making sure the samples were representative. Sodium and potassium contents in soil and feeds were determined by the Atomic Absorption Spectrometry methods and in hair by the Inductively Coupled Plasma-Optical Emission Spectrometry method. There were two dates for hair sample collection: I (10-14 days prior to calving) and II (after the first month of lactation). The results showed that Na and K concentrations were sufficient to meet animal needs. The sodium level in cow’s hair fell within the physiological range. Also potassium concentration complied with the referential standards (2000 mg·kg-1 d.m.) and approximated 2040 mg·kg-1 d.m.