The retention of copper in sheep fed palm kernel cake supplemented with molybdenum, molybdenum plus sulphur and zinc

Abstract

An  experiment  was  conducted  to  determine  the  effect  of  supplementation  with molybdenum (Mo), Mo + Sulphur and zinc (Zn) on the digestibility of copper (Cu) in sheep fed palm kernel cake (PKC) based diet. Twenty local cross-bred sheep were allotted to four groups and given PKC-based diets containing either, 0 (Control), 20 ppm Mo +1000 ppm sulphur (S)  (Diet MoS), 500 ppm Zn (Diet ZN) or 30ppm Mo (Diet Mo). The apparent digestibility of Cu in sheep fed the control diet  was  significantly  higher  (p<0.01)  compared  to those  in  the  other  diets.  The  retention  of  Cu  for sheep  on  Diet  MoS  was  significantly  lower  (p<0.05)  (2.49%),  compared  to  the  other  dietary treatments. Subsequently, the faecal excretion of Cu for sheep fed Diet MoS, Diet ZN and Diet Mo higher  (p<0.05)  than  the  control  group.  The  highest  urinary  excretion  of  Cu  was  also  observed  in sheep fed Diet MoS (0.64 ppm). It appears that the retention of Cu was effectively reduced  when Mo + S  was supplemented in PKC based diet. The effect of Zn and Mo alone, on urinary excretion of Cu was lower when compared to Mo + S. The liver and kidney Cu concentration of sheep fed Diets MoS, Diet  ZN  and  Diet  Mo  were  significantly  lower  (p<0.05)  than  those  in  the  control  group.  It  can  be concluded that supplementing with either Mo, Zinc or Mo+S significantly reduced the retention of Cu in sheep and thet Mo+S appears to be more effective than Mo or Zn in reducing the concentration of Cu in the  liver and kidney.