Soil-plant-animal Continuum Concerning the Certain Micro-mineral Status of Indigenous Sheep in Hot Semi-arid Regions

Abstract

Background: Semi-arid regions have a large livestock population that grazes on nutrient-depleted natural grasses and crop leftovers, resulting in mineral shortages. The goal of this study was to determine the amounts of iron (Fe), copper (Cu), manganese (Mn) and zinc (Zn) in soil, pasture and sheep serum in semi-arid areas with low rainfall (498-522 mm) in order to construct a soil-plant-animal continuum and recommend solutions to increase trace element availability. Methods: Samples were collected from different parts of the continuum [Soil (n=50), pasture (n=50) and blood samples from sheep (n=50)] from the selected study area and the trace elements were analyzed after digestion using atomic absorption spectrophotometer. Descriptive, correlation and t-test analyses were carried out to categorize the deficiency, their significance and soil-plant-animal continuum. Result: Although most soil samples were found to be below threshold levels, most straws and stovers in the field had marginal levels of these micro-minerals. Most sheep serum samples had levels of different micro-minerals that were below the threshold level, implying that many indigenous sheep are deficient in micro-minerals. Although there was a substantial association between feed, fodder and sheep serum, there was no such correlation between trace mineral levels in sheep serum and soil. A higher percentage of these micro-minerals in sheep faeces implies that these nutrients are truly recycled through faeces and urine in semi-arid rural areas. To address the sub-clinical micro-mineral insufficiency in semi-arid regions, micro-mineral supplementation, particularly Zn, Cu and Mn, is required.