부산대학교 도서관

Common levels of blood metabolites of post-calving crossbred dairy cows under different production systems in Batangas and Laguna, Philippines were determined to deduce the general health and nutritional status of the animals. Thirty-six apparently healthy Holstein Friesian x Sahiwal post-calving cows were selected using purposive sampling. Blood samples were collected via the coccygeal vein and were analyzed for non-esterified fatty acids (NEFA), betahydroxybutyrate (BHBA), glucose, cholesterol, blood urea nitrogen (BUN), calcium (Ca), phosphorus (P), potassium (K) and magnesium (Mg). Mean NEFA, BHBA, cholesterol and P concentrations in the blood and NEFAto- cholesterol ratio were within the normal range. Mean glucose and BUN concentrations, on the other hand, were higher than the maximum range while macro minerals Ca, K and Mg were lower than the minimum normal levels. Only mean NEFA concentrations from the intensive and semi-intensive production systems were significantly different (P<0.05). Mean concentrations of BHBA, glucose, cholesterol, BUN, Ca, P, K and Mg and NEFA-to-cholesterol ratio had no significant differences among the three production systems. Therefore, apparently healthy crossbred post-calving dairy cows from Batangas and Laguna did not experience negative energy balance but had macro mineral (Ca, K and Mg) deficiency when compared with reference standards in temperate countries. [ABSTRACT FROM AUTHOR]