Seasonal Variation in Sodium Status of Soil, Forage, Feed, Water and Small Ruminants Grazing in the Semi-arid Region of Pakistan
Zafar Iqbal Khan,
Hans- Werner Koyro,
Muhammad Saeed Akhtar
An investigation was conducted in central region of Punjab, Pakistan to study the relationship of mineral (Na) in soil, plantand animal systems to enable prediction of sodium status of three different classes of goats and sheep grazing the pasture. From goat and sheep ranch soil, forage, feed, waterand animal samples (Blood plasma, milk, faecesand urine) were collected fortnightly during winter and summer seasons. At goat ranch it was found that seasons did not affect soil, forageand plasma Na+ concentrations. These samples were lower than the required range in relation to Na+ levels. The fecal, urineand milk Na+ losses were found to be responsible for low plasma Na+ status in different goat classes. At sheep ranch soil, feedand plasma, milk and urine sodium concentrations in lactating sheep were affected by seasonal changes. Forage sodium level during summer was at marginal deficient and during winter it was slightly deficient. In lactating sheep plasma had marginal deficient level of sodium in winter and moderate deficient level in summer. While in non lactating sheep plasma sodium was also moderately deficient in summer and marginal deficient in winter and in male sheep moderately deficient level of sodium in plasma was found in summer only. Fecal and urine loss of sodium in lactating and non lactating animals was lower during winter than those during summer. Milk loss of sodium was found to be higher in winter than that in summer. From these results it is concluded that Na+ status of goats and sheep in this specific region needs supplementation with mixture of salt containing Na+ to enhance the Na+ levels of grazing animals.