Good nutrition is essential, especially in hot weather. Heat reduces cows' appetites and less feed means less production. Hot weather also changes the way cows process and use nutrients.
Summer nutrition strategies aim to:
- Maintain daily intakes of ME and other nutrients.
- Maintain digestibility of feed in the gut.
- Free up more energy for milk production by maintaining normal heat balance.
- Provide energy in the form that best suits the cows in their challenged state.
Drinking water. How much water do cows need in hot weather? Allow for 200 - 250 litres per cow per day in hot weather - double what cows usually need each day. Make sure cows have access to plenty of cool drinking water wherever they are during the day. A big water trough on the exit side of the dairy is a must. Provide a minimum of 0.75m water trough space per cow at your feed-out facility. Water pipes should be 75mm in diameter, with sufficient pressure to provide 20 litres per cow per hour, so that troughs cope with periods of peak demand.
Summer nutrition strategies - fibre, starch, protein, mineral and buffers
With daily feed intake reduced, and more grain / concentrates being fed to maintain energy intake, the quality and amount of fibre sources fed is critical. High quality fibre is the best tool you have to maintain rumen stability and to increase nutrient density without producing excessive metabolic heat. Heat stressed cows have a greater need for glucose.
Most farmers notice falls in milk production when cows get hot. This results in substantial losses in milk income, but reduced in-calf rates, low milk protein and fat tests, liveweight loss, higher sometic cell counts, more clinical mastitis cases and other cow health problems can often double these losses.
If you can develop an effective heat stress management program there are substantial benefits to be gained.
Cool Cows (external website)
Dairy Australia is helping farmers adapt to this changing operating environment through the Cool Cows program, which offers dairy farmers and their advisers information and tools to help stay ahead of heat stress.