Hepatic Cobalt and Copper Levels in Lambs in Norway

T Sivertsen,C Plassen

doi:10.1186/1751-0147-45-69

Abstract

Cobalt and copper concentrations were measured in 599 lamb livers collected at slaughter from 58 sheep flocks in 6 different parts of Norway in 1993. Information about pasture, additional feeding and mineral supplements in the flocks was obtained through a questionnaire. Average hepatic levels of cobalt in the lamb flocks varied from <0.003 to 0.22 μg/g ww, and of copper from 5 to 240 μg/g ww. Flocks with deficient or marginal cobalt status were found in all parts of southern Norway, but primarily in the west and south-west. Some flocks with marginal copper status were found in the south-west, while flocks with signs of excessive hepatic copper concentrations were found mainly in inner parts of central and northern Norway. Hepatic copper concentrations were significantly higher in lambs that had grazed mountain pastures than in those that had grazed lowland pastures in the summer.

Highlights

Cobalt deficiency in the form of ovine whiteliver disease (OWLD) is a documented problem in lambs grazing cultivated pastures in the south-western parts of Norway (Ulvund 1990a)
We think that an average cobalt level below 0.025 μg/g ww in a sheep flock should be considered marginal
In the present survey we found 9 flocks with average hepatic cobalt levels below 0.025 μg/g ww (Table 2)

Summary

Introduction

Cobalt deficiency in the form of ovine whiteliver disease (OWLD) is a documented problem in lambs grazing cultivated pastures in the south-western parts of Norway (Ulvund 1990a). As the primary sign of the disease is illthrift in grazing lambs, it may be unnoticed and under-diagnosed in areas where it is less known. On this basis we decided to undertake a survey of hepatic cobalt levels in lambs from different parts of Norway. Copper is another element of concern in sheep husbandry. Cases of chronic copper poisoning with acute haemolytic crisis occur regularly in a number of inland districts, and may be a serious problem in some flocks (Sivertsen & Wie 1996).

Methods

Results

Conclusion