| dc.description.abstract | Background: The imbalance of macro mineral household around calving can lead to fatal consequences. Clinical hypocalcaemia is featured by the recumbence of the animal, while recently, the definition of subclinical hypocalcaemia has also been stated. This disease is characterised by a drop in the blood calcium concentration, not necessarily leading to clinical recumbency, but other diseases are consequential. Objectives: The objectives of our study were to evaluate the occurrence of subclinical hypocalcaemia in 5 Hungarian dairy farms. The goal was to study the incidence, depth, and some effecting factors (lactation, days in milk) of subclinical hypocalcaemia (SCH). Materials and methods: Blood samples were collected from the coccygeal vein of dairy cows in the first seven days of lactation once. Serum total calcium concentration (tCa) and non-esterified fatty acids (NEFAs) were measured with spectrophotometry. SCH incidence was calculated at the farm level, and the effect of parity and days in milk was also evaluated. Pearson correlation was calculated to find a correlation between tCa and NEFA values.Results and discussion: The incidence of SCH ranged between 26,9 and 53,6 percent, respectively. In the first three days of lactation, SCH was affecting the majority of the animals signalling that the adaptational period of the study population was differing between farms. Interestingly, animals on days 5, 6, and 7 also showed SCH concentrations in the blood, suggesting that the adaptational period cannot be monitored from one measurement. This finding has importance in individual treatments of the animals. Heifers in the first lactation did not suffer from SCH; therefore, prevention should focus on animals from the second parity. NEFA concentrations did not correlate statistically with tCA concentrations; however, animals with increased lipolysis had higher tCa concentrations. | en_US |
