The long-term accumulation and depletion of copper in the liver of different breeds of sheep fed diets of differing copper content

Abstract

Changes in Cu concentration in the livers of adult Scottish Blackface (B), Welsh Mountain (W) and B x W ewes fed diets containing 4, 9, 17 and 29 mg Cu/kg D.M. were measured over a 28-week period. Measurement continued during two further periods of 18 weeks when first all sheep were fed the diet containing 4 mg Cu/kg D.M. and finally, when 4 mg Mo/kg D.M. was added to this diet.During the first period the increase on all diets was least in B ewes and, apart from the 4 mg Cu/kg D.M. diet, greatest in W ewes; this difference increased as the Cu in the diet increased. The rate of increase for all ewes diminished towards the end of the period. All breed types retained proportionately less Cu in their livers as the Cu in the diet increased; at one extreme B ewes fed 17 or 29 mg Cu/kg D.M. retained equal amounts.When during the second period all sheep were fed the 4 mg Cu/kg D.M. diet the Cu concentration in their livers decreased, the rate of decrease being greatest for ewes whose mean concentration in the liver was highest, but at similar concentrations the decrease was greater in B than W ewes. During the final period the decrease was faster and was again associated with the mean Cu concentration, but the decrease was not significantly affected by breed.Throughout the trial, W ewes had the highest concentration of Cu in their plasma, whilst B ewes and ewes fed the 4 mg Cu/kg D.M. diet throughout had the lowest concentrations both in plasma and in their kidneys at slaughter.The results show that breeds differ in their ability to retain Cu from the diet in their livers. The magnitude of these differences depends on the intake of Cu and Mo from the diet and is affected by the concentration of Cu in the liver. Breed differences in the absorption and endogenous loss of Cu are suggested.

The macro‐ and micro‐element content of swedes and kale in Southland, New Zealand, and the effect of trace element‐amended fertilisers on their Co, Se, and Cu concentrations

“…As livestock are fed these crops for a short period, usually 6-8 weeks, the best approach to prevent trace element deficiency problems in brassica crop-fed animals is to ensure that the animals have an adequate trace element status, that is, high liver concentrations of vitamin B 12 (Co), Se, and Cu, before being fed swedes and kale (Woolliams et al 1983;Millar & Meads 1988). Although the tissue trace element stores will become slowly depleted during the winter feeding of brassica crops they will, however, recover when Table 3 The dietary mineral requirements of sheep and cattle and the mean mineral composition of swedes and kale in this study.…”

Association of Oxidative Stress Biomarkers and Antioxidant Enzymatic Activity in Male Infertility of North-East India

“…This method employs xanthine and xanthine oxidase (XOD) to generate superoxide radicals which react with 2-(4-iodophenyl)-3-(4-nitrophenol)-5-phenyltetrazolium chloride (I.N.T) to form a red formazan dye. The superoxide dismutase activity is then measured by the degree of inhibition of this reaction [16].…”

Effect of Co, Cu, Fe, Mn, Mo, Se, and Zn supplementation on the elemental content of soft tissues and bone in sheep grazing ryegrass/white clover pasture

“…The change in plasma Cu of the ewes when the dietary Cu was increased from 5 to over 10 mg/kg DM occurred within3 weeksand thenremained relatively constant (Woolliams et al 1985) whereas the liver Cu concentrations increased more slowly over 28 weeks. The rate of hepatic Cu uptake was least in the Blackface and, except for the 4 mg Cu/kg DM diet, greatest in the Welsh Mountain ewes (Woolliams et al 1983). In this investigation increasing the Cu intake of Romney wethers from 9.3-17.3 mg/day had no effect on plasma or extrahepatic tissue Cu levels but increased the liver Cu levels mg Cu/kg fresh tissue).…”

“…Increasing Cu intake further had only smalleffects on plasmaCu (Woolliamset al 1983). Breed differences in plasma Cu levels were found when all ewes were given a low Cu diet (4 mg/kg DM) as the Cu concentrations (mg/litre) for Blackface, BlackfaceX WelshMountain, andWelsh Mountain ewes were 0.61, 0.86, and 0.91 respectively (Woolliams et al 1983). The change in plasma Cu of the ewes when the dietary Cu was increased from 5 to over 10 mg/kg DM occurred within3 weeksand thenremained relatively constant (Woolliams et al 1985) whereas the liver Cu concentrations increased more slowly over 28 weeks.…”