Effects of blood sample collection and preparation methods on concentrations of glucose and nonesterified fatty acids in dairy cattle

Measurement of concentrations glucose and nonesterified fatty acids (NEFA) in blood is common nutrition physiology studies. Proper collection preparation conditions the have been less well studied dairy cattle. The objective this experiment was to determine NEFA prepared with different anticoagulants (heparin vs. EDTA), use fluoride as a glycolysis inhibitor, time until centrifugation (<30 min 2.5 h), plasma versus serum. Blood samples were obtained from 30 lactating cows 15 milk-fed calves into 5 evacuated test tubes. Three tubes contained K3 EDTA 1 tube heparin prepare plasma, fifth serum separator tube. One inverted divided 2 containing NaF. NaF centrifuged within others held on ice for another h before centrifugation. min. Glucose measured using enzymatic kits. Data data sets representing normal cow values or elevated NEFA. For concentrations, results indicated that decreased 2-h holding did not affect results, resulted lower than plasma. low addition significant decrease concentration. effect sitting samples, but contrary our expectations, rather increase it. Heparin an anticoagulant relative EDTA. samples. Serum similar concentrations. In high experimental power limited due small sample size, tended result greater produced compared differ While differences among methods biological significance, these provide guidance processing intended assay.