|
Changes in Metabolites Concentration in Nguni and Crossbred Calves on Natural Pasture |
M. Mapekula, C. Mapiye, M. Chimonyo |
|
|
|
|
Abstract |
Accurate assessment of the nutritional status of Nguni cattle is becoming increasingly important in determining their mechanism for adaptation to challenging environments. Changes in body weights and concentrations of total protein (TP), albumin, globulin, glucose, cholesterol, non-esterified fatty acids (NEFA), phosphorus (SIP), calcium and magnesium were determined in Nguni and crossbred calves raised on natural pasture from birth until weaning. At an early age, TP concentration in crossbreds was higher (p<0.05) than that of Nguni calves. However, TP levels increased with age in Nguni calves so that Nguni’s had higher (p<0.05) TP levels than crossbreds at weaning. Nguni calves had higher (p<0.05) glucose concentrations than crossbreds in all the ages except in the third month. Serum NEFA levels in Nguni calves were higher (p<0.05) than in crossbreds at all ages except for the second month. Calcium levels decreased (p<0.05) with age in both genotypes. The blood TP concentrations tended to decrease (p<0.05) as body weight increased up to 80 kg, thereafter blood TP concentration increased (p<0.05) as body weight increased. Calcium concentrations in crossbred calves decreased (p<0.05) quadratically as the body weight increased. There was, however, a linear increase (p<0.05) in calcium concentrations in Nguni calves. The higher NEFA and TP concentrations at weaning and the TP increase in Nguni calves beyond 80 kg suggest that Nguni’s utilise fibrous feeds better than crossbreds. |
Keywords:
Age; Calcium; Glucose; Non-esterified Fatty Acids; Total Protein; Calf |
|