Abstract
Investigations were conducted in the southern part of Punjab, Pakistan to evaluate the mineral status of goats, to determine the classes of animals which are most susceptible to specific mineral deficiencies or toxicities, as reflected by low tissue fluids mineral concentrations in animals, and to study the effect of season of the year on the mineral availability to animals. During both the winter and summer season, soil, forage, feed, water from pasture and blood, milk, faeces, and urine samples from lactating, non-lactating, and male goats were collected fortnightly and analyzed for macro- and micro mineral concentrations. Soil samples taken from the pasture grazed by goats had adequate levels of both calcium and magnesium during winter and summer. While forage contained marginal deficient Ca2+, Mg2+. Feed Ca2+ concentrations were moderately deficient during both seasons. The effects of feed supplement at goat ranch in raising the plasma mineral level was different in different groups of animals in different seasons. The moderate deficient level of plasma Ca2+ and marginal deficient level of Mg2+ during winter and summer in lactating goats, while in non-lactating goats in plasma, moderate levels of Ca2+ and marginal deficient levels of Mg2+ during both seasons were found. Plasma of male goats contained marginal deficient levels of Ca2+ during winter, and Mg2+ during summer, while moderate deficient levels of Ca2+ were found in summer. The fecal Ca2+ in non-lactating animals were high in summer, and Mg2+ high in winter. Urine mineral concentrations of lactating animals were above optimum level during winter, and in non-lactating animals both the urine minerals were high during the winter. Concentrations of milk minerals such as Ca2+, and Mg2+ were lower in winter than those in summer. Ca2+ in lactating goats, and Mg2+ in male goats were excreted more during winter when comparison was made among different classes of goats because animal had low absorption for these minerals or for their body requirements. Urine mineral concentrations such as Ca2+ in lactating goats, Mg2+ in non-lactating goats were higher in winter than that in summer. The minerals which had more absorptive capacity through intestinal tract had been excreted more in urine and translocated to plasma of the animals. Ca2+, and Mg 2+ contents of milk in lactating goats was found to be lower during winter showing less availability and absorption of these minerals in this season. The findings of this work showed that the distribution of nutrients in different parts of the animal body was dependent on the rate of absorption through gastrointestinal tract of the animals. Despite the adequate levels of certain minerals found in forage and feed in particular season, the animals showed deficiency of these elements. So further study to eliminate unnecessary minerals in the supplement showing antagonism and thus responsible for reducing the bioavailability of certain essential minerals in a particular season, is needed. On the basis of these results both minerals in soil were adequate for the normal growth of plant. But were deficient in forage on goat ranch particularly during summer season. However, the supplementation of feed containing minerals seemed to have contributed much to the well being of the animals.
