TRANSFER OF MAGNESIUM FROM SOIL AND FORAGE TO GOATS GRAZING IN A SEMIARID REGION OF PAKISTAN: INFLUENCE OF SEASONS AND SAMPLING PERIODS

The investigations were conducted in a goat farm at "Livestock Experimental Station" located in the South-western Punjab. The purpose of the investigations was to determine the influence of seasons and sampling periods, the transfer of magnesium from soil and forages to grazing goats in this semiarid region as to evaluate Mg requirement of the grazing livestock. Soil, forage and blood samples from lactating/ non-lactating and male grazing animals were taken fortnightly, four times during summer and winter. Soil samples taken from the pasture grazed by goats had adequate levels of Mg during winter and summer, while forage contained marginal deficient Mg. The marginal deficient levels of Mg in lactating goats were observed during winter and summer, while marginal deficient levels of Mg in the plasma of non-lactating goats were observed during both seasons. Plasma of male goats contained marginal deficient levels of Mg during summer. On the whole, the plasma Mg concentration may be considered inadequate mainly due to unavailability of this mineral from the dietary sources. It is concluded that high bio-available Mg supplementation is needed for increased animal productivity in this region.