Philipp J Vet Anim Sci 2018 44 (2): 169-176 METABOLIC PROFILE OF POST-CALVING CROSSBRED DAIRY COWS UNDER DIFFERENT PRODUCTION SYSTEMS IN A TROPICAL ENVIRONMENT Karla Joy S. Ty 1 , Amado A. Angeles 1 , Gabriel L. Lagamayo 2 , Florinia E. Merca 3 and Severino S. Capitan 1 ABSTRACT Common levels of blood metabolites of post-calving crossbred dairy cows under diferent 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-esterifed fatty acids (NEFA), beta- hydroxybutyrate (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 NEFA- to-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 signifcantly diferent (P<0.05). Mean concentrations of BHBA, glucose, cholesterol, BUN, Ca, P, K and Mg and NEFA-to-cholesterol ratio had no signifcant diferences 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) defciency when compared with reference standards in temperate countries. Keywords: lactating cows, metabolite, negative energy balance, post-calving 1 Institue of Animal Science, College of Agriculture and Food Science (CAFS), University of the Philippines Los Baños (UPLB); 2 National Dairy Authority (NDA), Diliman, Quezon City; 3 Institute of Chemistry, College of Arts and Sciences (CAS), UPLB. (email: karlajoysty@gmail.com) INTRODUCTION The dairy industry of the Philippines is still in its developing stage compared to other tropical countries. The main concern of Filipino dairy farmers, aside from the high cost of stocks, is the adaptability of dairy cattle in the Philippine environment which greatly afects production performance. Most of the dairy animals in the country are crossbreds, taking advantage of the higher milk production of the temperate breed and the resistance to heat and parasites of the zebu breed. However, peak productivity cannot be obtained with breed alone, especially during the transition period wherein 75% of all diseases usually