Evaluation of trace elements in forages and their effect on gastrointestinal parasite burden in grazing sheep

Abstract

This study was designed to evaluate the trace elements (minerals) in forages fed to sheep and their effect on gastrointestinal parasite burdens. The ultimate objective was to determine the correlation between the burden of gastrointestinal (GI) parasites and the level of trace minerals in sheep serum as a result of the forages they grazed on.A total of 384 faecal samples were collected from sheep in each of the districts (Sialkot and Multan) and examined quantitatively using the McMaster technique. Serum collected from them and plants were pre-treated, and spectrophotometry was used to determine the concentration of trace minerals (Mn, Co, Cu, and Zn). The level of these trace elements differed significantly (P < 0.05) in forages from both districts. In the district of Sialkot, the highest concentrations (mg/Kg) of Zn (38.53 ± 0.16) were found in Cichorium intybus, Cu (41.57 ± 0.07) in Cynodon dactylon, Mn (39.61 ± 0.05) in Parthenium hysterophorus, and Co (1.42 ± 0.03) in Coronopus didymus. In the district of Multan, the highest concentrations (mg/Kg) of Zn (39.43 ± 0.46) were found in Cichorium intybus, Cu (25.76 ± 0.36) in Cynodon dactylon, Mn (34.29 ± 0.53) in Launaea nudicaulis, and Co (1.74 ± 0.08) in Brachiaria raptens. The prevalence of GI parasites in sheep populations in district Sialkot was 34%, while in district Multan, it was 32%. In tehsil Sialkot of district Sialkot, Zn and Cu were significantly (P < 0.05) correlated with eggs per gram (EPG) of faeces, while in tehsil Multan City of district Multan, only Cu was significantly (P < 0.05) correlated with EPG. The potential mechanism behind the role of trace mineralsin lowering the burdens of GI parasites requires more investigation. It is recommended that plants with high content of trace minerals should be utilized as part of comprehensive preventive and control strategies against GI parasitism in ruminant animals like sheep.