Dairy cows use and prefer feed bunks fitted with sprinklers

Area of Science:

• Animal Science
• Dairy Husbandry
• Environmental Physiology

Background:

• Heat stress negatively impacts dairy cow productivity and welfare.
• Sprinkler systems are used to mitigate heat load, but behavioral responses can vary.
• Feed bunk sprinklers are a common cooling method on US dairies.

Purpose of the Study:

• To determine the behavioral effects of feed bunk sprinklers on lactating dairy cows.
• To assess dairy cow preference for feed bunks equipped with sprinklers versus those without.
• To evaluate the impact of sprinklers on core body temperature and feeding behavior under heat stress.

Main Methods:

• Lactating Holstein cows (8 groups of 3) were studied in warm ambient conditions.
• A crossover design was used for a single-treatment phase (2 days/treatment) with and without sprinklers.
• A choice phase assessed preference over 5 days with ad libitum feed access in both treatments.
• Behavioral data (time spent feeding, standing) and core body temperature were recorded 24h/d.

Main Results:

• Sprinklers increased time spent feeding (3.5 vs. 2.5h/24h) and standing without feeding (4.3 vs. 2.3h/24h).
• Average 24-h core temperature was reduced (38.8 vs. 39.2°C) with sprinklers, especially on warmer days.
• Cows showed a strong preference for the sprinklered feed bunk (78% of time), increasing with heat load.
• Cows protected their heads from direct spray but still utilized the sprinklers.

Conclusions:

• Lactating dairy cows readily use and clearly prefer feed bunk sprinklers for cooling.
• Sprinklers effectively reduce heat load and maintain feeding time during warm weather.
• Despite avoiding direct head wetting, the overall cooling benefit drives preference for this system.