Assesment of iron, cobalt and manganese in soil and forage: a case study at a rural livestock farm in Sargodha, Pakistan

This investigation was carried out at a rural livestock farm in district Sargodha, Pakistan to assess the effects of different seasons on the flow and status of some essential minerals from soil to forage. Soil and forage samples were taken concurrently for four months after one month interval and analysed for Fe, Co, and Mn levels after wet digestion. The results showed that there was a non-significant effect of sampling periods on soil Co, Fe, and Mn with an inconsistent variation in Co and Fe, and a consistent variation in soil manganese at sampling intervals. All mean values of soil Fe and Mn were higher than the requirements of forage crops, while the reverse was true for soil Co in this investigation. The effect of sampling periods on forage Fe and Co was found to be non-significant, while the reverse was true for forage Mn with a consistent increase in forage Fe and decrease in Co and Mn with the time of sampling. The higher transfer factor from soil to forage for Fe and Mn in December and Co during the month of January was observed during this study. From this pattern of nutrient transfer from soil to forage, a toxic range of these nutrients is possible for the animals at any time during the year. So supplementation with a specific balanced mineral mixture containing minerals which antagonize Co, Mn and Fe in animals digestive tracts is immediately warranted at this animal farm. (author)