The influence of two stocking rates on diet composition and intake of sheep in a three camp rotational grazing system in the central Orange Free State
A study was made of the nutritive value of native pasture for sheep in a 3-camp rotational grazing system at 2 stocking rates. The experiment covered a period of 12 months. Differences in crude protein content of herbage samples collected by oesophageal fistulated sheep were not statistically significant (P ≤ 0,05) between stocking rates. In vitro digestibilities of these samples were significantly higher at the lower stocking rate at times but the opposite was also true. Differences in botanical composition of the plant cover in the 2 stocking rates could have been responsible for some of the observed differences. Feed intake was also measured at various stages in order to determine whether the protein and energy requirements of the sheep were being met. It was found that the digestible organic matter (DOM) intake of the sheep at the low stocking rate was below the amount required for maintenance only during July/August 1973. In the higher stocking rate, DOM intake was insufficient for maintenance during October 1972, January 1973 and May/June 1973. The results also show that digestible protein intake of the sheep at the low stocking rate was below the maintenance requirement during July/August 1973. The sheep at the higher stocking rate experienced a digestible protein deficiency in January 1973.