Take a look at this. We haul water every day and some summer days have to make 2 trips.
Table 1. Estimated daily water intakes (gallons per head per day) for lactating beef cows, bred cows, dry cows, and bulls.
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Dry Cows,
Monthly Lactating Bred Cows,
Month Average Temp Cows and Heifers Bulls
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(�F) - - gallons per head per day - -
January 36 11.0 6.0 7.0
February 40 11.5 6.0 8.0
March 50 12.5 6.5 8.6
April 64 15.5 8.0 10.5
May 73 17.0 9.0 12.0
June 78 17.5 10.0 13.0
July 90 16.5 14.5 19.0
August 88 16.5 14.0 18.0
September 78 17.5 10.0 13.0
October 68 16.5 8.5 11.5
November 52 13.0 6.5 9.0
December 38 11.0 6.0 7.5
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Adapted from GPE-1400, Water Requirements for Beef Cattle.
The spacing is not very good, but you get the point. The first column is average daily temp, second column for lactating cows, third column for dry cows, bred cows, and heifers, fourth column for bulls.