Individual cow feeding is increasing as more New Zealand farmers buy in-shed feeding systems. A DairyNZ technology-use survey in 2013 found that a third of all farm dairies have in-shed feeding systems installed, with 62 per cent of these rotary and 22 per cent herringbone.
Most of these systems feed all cows the same amount (flat-rate feeding), whereas a quarter can feed individual amounts (individual or differential feeding) according to rules set by the farmer.
CURRENT FARMER PRACTICES
The project initially surveyed New Zealand farmers and farm advisers to gain insight into existing practices.
The individual cow (or group) feeding strategies most commonly used by New Zealand farmers were: feeding to milk production (58 per cent), breed or age (50 per cent), liveweight (42 per cent), stage of pregnancy (40 per cent) and BCS (37 per cent).
Farmers generally reported that there were benefits in individual cow feeding but there was a lack of clarity concerning the most profitable feeding strategies.
COMPARING FEEDING STRATEGIES
Simulation modelling was also used to explore common criteria for individually feeding cows (milk production, age, genetic merit, liveweight and BCS) and determine any difference in the milksolids response compared with flat-rate feeding.
The same total amount of supplement was fed in each scenario and results from this modelling indicated there was no benefit to individual feeding.
EXPLORING FLAT-RATE AND INDIVIDUAL COW FEEDING
The final stage of the project was a field study carried out this spring to compare flat-rate feeding with individual cow feeding.
Four herds of 18 cows were flat-rate fed 4kg DM of supplement/cow/day.
Another four herds were individually fed according to their milk production ranking.
The highest producing cows received 6kg DM supplement/day, the middle cows received 4kg DM/day and the lowest producers received 2kg DM/day. All herds were offered the same total amount of supplement and were managed identically on pasture.
Results and information from the project will be available to farmers mid-2015.
This project is funded by the Sustainable Farming Fund and DairyNZ.