Summer is in full force. Cows need lots of water. Calves do too.

A study by Wickramasinghe and colleagues published earlier this year examined differences in offering calves free-choice water starting at day 0 vs. day 17 (the average age from the 2014 USDA National Animal Health Monitoring System study). The study’s Holstein calves were bottle fed ad lib volumes of milk at 6 quarts per day (over 3 feedings) until 14 days of age, then 10 quarts per day (over 3 feedings) from 14 to 42 days, then 3.4 quarts per day (1 feeding) until weaning at 49 days.

What did they discover?

• Once they had water available, the starting-at-day-17 calves drank more water through the rest of the preweaning period.
• Calves with water from day 0 drank more milk than the group starting water at day 17.
• Starter intake did not differ significantly between the two groups.
• Calves with water available from day 0 were, on average, taller and longer at weaning and heavier at 5 months than those who didn’t have water until day 17.
• The two groups had essentially the same incidence pattern of scours.

These results are in accord with an earlier study published in 1984 by Kertz et al. With a more limited milk allowance and much younger weaning age (28 days!), calves with free access to water ate more calf starter and gained more weight with no difference in incidence of scours compared to calves with no water available.

The bottom line: Make sure your calves have water! Even for the youngest ones, water will help them grow.

The papers:

Wickramasinghe et al. Drinking water intake of newborn dairy calves and its effects on feed intake, growth performance, health status, and nutrient digestibility. Journal of Dairy Science, 2019, 102:377-387.

Kertz et al. Ad Libitum Water Intake by Neonatal Calves and Its Relationship to Calf Starter Intake, Weight Gain, Feces Score, and Season. Journal of Dairy Science, 1984, 67:2964-2969.