Differential Effects of Sodium and Magnesium Sulfate on Water Consumption by Beef Cattle

Authors

A. S. Grout, University of British Columbia
D. M. Veira, Agriculture and Agri-Food Canada
D. M. Weary, University of British ColumbiaFollow
M. A. G. von Keyserlingk, University of British Columbia
D. Fraser, University of British ColumbiaFollow

Document Type

Article

Publication Date

2006

Abstract

The existing guidelines for maximum sulfate (SO₄) in cattle drinking water are based on Na2SO₄, although many water sources contain greater concentrations of MgSO₄. Two experiments compared the effect of different SO₄ salts on water consumption and fecal DM of cattle. In Exp. 1, 8 yearling heifers (initial BW = 345 ± 8 kg; mean ± SD) were watered twice daily with tapwater or water containing Na₂SO₄ or MgSO₄ at target levels of 1,500, 3,000, or 4,500 mg of SO₄/L for 2-d treatment periods separated by 2 d of access to tapwater. In Exp. 2, 16 yearling cattle (initial BW = 421 ± 24 kg) were watered twice daily with tapwater (16 mg of SO₄/L) or water containing Na₂SO₄ at target levels of 2,000 mg of SO₄/L (low Na₂SO₄), MgSO₄ at 2,000 mg of SO₄/L (low MgSO₄), or MgSO₄ at 4,000 mg of SO₄/L (high MgSO₄) in 21-d treatment periods separated by 7-d periods on tapwater. The first 10 d of each period were allowed for adjustment to the treatment, and the final 11 d was considered the treatment period for analysis purposes. Treatments were applied in an incomplete Latin square, where each animal was exposed to 3 of the 4 treatments. In Exp. 1, the average daily water consumption decreased linearly as the SO₄ concentration increased for MgSO₄ (P = 0.0001) but not for Na₂SO₄ (P = 0.39). In Exp. 2, the average daily water consumption was less for cattle on the high-MgSO₄ treatment than for cattle on the low-MgSO₄ treatment (P = 0.0001), and cattle on the low-MgSO₄ treatment tended (P = 0.09) to drink less than those on the tapwater treatment. Fecal DM was greater for cattle on the high-MgSO₄ treatment than for those on the low-MgSO₄ treatment (P < 0.01). These findings indicate that cattle reduce their consumption of water containing high (≥ 4,000 mg of SO₄/L) concentrations of MgSO₄, even after a given time to adjust to the treatment; such reductions may be accompanied by an increase in fecal DM.

Recommended Citation

Grout, A. S., Veira, D. M., Weary, D. M., von Keyserlingk, M. A. G., & Fraser, D. (2006). Differential effects of sodium and magnesium sulfate on water consumption by beef cattle. Journal of animal science, 84(5), 1252-1258.