Effect of high and sustained zinc supplements on trace element metabolism in sheep

J. Lee, N.D. Grace, S. Martell

DSIR Grasslands, Private Bag, Palmerston North, New Zealand

Proceedings of the New Zealand Society of Animal Production. 1991, 51: 173-178

Three groups of 2th Romney wethers were given 0, 12g ZnO fortnight-1 and 12gZnO week-1 respectively for 18 months. Plasma trace element levels were monitored regularly over this period. At the end of the trial the animals were slaughtered and various organis, muscle, skin and wool were removed and analysed for a wide range of elements and for metallothionein.

Zinc treatment resulted in significantly elevated Zn in plasma, red blood cells, liver, kidney, intestine and pancreas. Copper concentrations in liver (272 ± 44 v 471 ± 45 ug g-1 dry weight) and kidney (17 ± 0.8 v 24 ± 1.6ug g-1 dry weight) were significantly (<0.001) increased in the weekly Zn treatment group compared with the control group. Plasma Cu levels were not affected. Metallothionein levels in livers from the weekly treatment group were increased 10-20 fold over those from the control group (3.6±0.9 and 0.26±0.1 mg g-1 dry weight respectively). In the weekly treatment group 76% of the total liver Cu and Zn was bound to MT compared with 10% in control group livers.

Keywords: NZSAPAB; Zinc; copper; trace element metabolism; sheep; metallothionein; liver; tissues

Download abstract in text format
Last Updated 25-01-1997