Use of Biochemical Indicators to Evaluate The Nutritional Status of Lactating Cows

Nutrient requirement is important to the animal, especially to cope with the physiological demands. Tropical countries face ma.ny problems of feeding management associated with animal production. Protein,energy and minerals (calsium and phosphorous) are found in the blood and milk which can be collected in a simple mamier and used to detect the nutritional status of the animal. These blood and milk constituents could be reliable bio-chemical indicators associated with production states of animals. The objective of this research is to study the correlation between dry matter intake with milk production,levels of blood calcium, phosphorous, protein,and milk calcitun, phosphorous and protein and also urinary allantoin. Twelve lactating cows were devided randomly into 3 groups according to milk production. Group I, II dan Ill produced 15 1, 10 I and 5 l of milk per day respectively. All animals were fed concentrate and elephant grass at a level calculated for a cow producing 10 I of milk per day as recomended by NRC (1988). Results showed that group I,II and III consumed respectively 14.97; 14.13 and 13.68 kg dry matter. There were deficiencies of calsiiun and phosphorous intakes in group I (4.81% and 6.76%) but not in the other groups. Milk production decreased in group I (38.6%) as compared to group II,while production in group Ill increased by about 37.50%. Blood calcium and phosphorous concentrations increased in group III (12.6 % and 6.35 %). There was significant correlation between dry matter intake and milk production (i=0.7) but protein intake and urinary allantoin was not highly correlated.