[Study of ECG in lactating cows. 2nd communication: ECG compared to behavior of various parameters of mineral and carbohydrate-fat metabolism].

Metabolism checks were carried out on eight dairy cow stocks, with 155 high-performance cows in first lactation being electrocardiographically and biochemically tested. Determined with the blood-borne concentrations of glucose, ketone body, calcium, magnesium, and inorganic phosphorus. The electrocardiographic recording were compared with behaviours of the blood parameters, and PQ conduction was found to be shortened in hypoglycaemic animals. Changes in calcium and magnesium serum concentrations were found to produce tbe most unambiguous effects on a number of ECG components, and reciprocal influence of these two components was as well observed. No correlation with ECG were recordable from the other parameters.