Effect of phosphorus and calcium supplementation on growth performance of communally grazed goats in a semi-arid area
Abstract
The purpose of this study was to assess whether there exists a mineral deficiency especially phosphorus, calcium and magnesium in communally grazed "village" goats. Phosphorus deficiency has been reported to occur in both cattle and sheep in this region but not in goats. There is therefore a need to conduct this research to find the state of mineral concentrations of the above elements in the blood and faeces of goats as well as the pasture which they graze. This study was conducted at the Mafikeng University Campus, North West Province, South Africa. A total number of 24 female village goats, averaging one year of age and in different physiological states, were purchased from local farmers around Mafikeng. The goats were randomly grouped into two, the control and the supplemented groups. The supplemented group was fed dicalcium phosphate ad libitum in the evenings from June 2011 to May 2012. Faecal, blood and grass samples were collected monthly. Individual animals where also weighed on a monthly basis. Dicalcium phosphate supplement mildly influenced both faecal and serum P levels in treated goats compared to the untreated group. However, dicalcium phosphate supplemented goats, displayed more (P < 0.05) serum Ca and Mg concentrations indicating the significance of providing Ca and P supplements to grazing communal goats in this region. In terms of body mass gain, Ca and P supplemented goats also outperformed the unsupplemented goats throughout the trial period. There is a need therefore to supplement calcium and phosphorus to communally grazed goats so as to maintain normal body mass, serum calcium, magnesium and phosphorus levels.