Resource information
A study was conducted in dry and wet season to determine macro and micro mineral status of
growing sheep and goats in arid rangelands of northern Kenya. Forty four, 22 each of sheep and goats (1-2
year old), randomly purchased from three herds/flocks in study area, were sacrificed for whole liver and 12th
right and left ribs. Homogenized liver samples pooled from all the lobes and defatted bone ash from whole
left and right 12th ribs were used for determination of Ca, P, Mg, Cu, Fe, Zn and Mn status. Liver mineral
analysis, showed that in sheep Cu (303 vs. 184 mg/kg DM), Zn (94.1 vs. 83 mg/kg DM) and Mn (13.2 vs. 7.5
mg/kg DM) were higher (p<0.05) in wet than dry season. In goats, season had no effect on Cu (274.28 vs.
236 mg/kg DM) and Fe (183 vs. 171 mg/kg DM), but had significant influence on Zn (102 vs. 126 mg/kg DM)
and Mn (13.6 vs. 6.8 mg/kg DM). Sheep grazing in different pastures showed variation (p<0.05) in hepatic Zn,
Cu and Mn contents, while goat varied (p<0.05) in hepatic Cu, Fe and Mn concentrations. Rib analysis
indicated that season had significant effect (p<0.05) on sheep and goats DFF% ash. The rib Ca (359 vs. 362
mg/g), P (157 vs. 147 mg/g) and Mg (9.56 vs. 8.54 mg/g) contents of sheep was not influenced by season
and grazing area (p<0.05), whereas goats rib Ca (360 vs. 326 mg/g), P (142 vs. 165 mg/g) content was
affected by season and grazing area (p<0.05), but Mg showed no seasonal variation. In the wet season, liver
and bone tissue of sheep and goats indicated adequate body status of Ca, Mg, Cu, Zn, Fe and Mn. However,
in the dry season, sheep showed deficient levels of Zn, goats in Cu, while both species suffered from low
liver Mn and rib Zn reserves. With the exception of P which was marginal in all seasons, mineral deficiencies
affected animals mostly in the dry season. The liver and rib bone of sheep and goats has demonstrated
seasonal fluctuation in tissue mineral reserve. Evaluation of specific minerals in different periods and body
pools can be useful in the diagnosis of mineral status of animals. It can be concluded that, sheep and goats
would benefit from P, Cu, Zn and Mn supplementation, particularly in the dry season.
