30 August 2011

3 minute read

Oceania

"The recent cold snap has meant that many farms have covers lower than 1800kg DM/ha,” says Phillipa Hedley, DairyNZ farm system specialist.

“If you take action now and address the issue, getting cows in calf quickly should not be affected by lack of feed. Walk the farm, confirm the size of any deficit and then develop a plan on how to fill the deficit.”

Ms Hedley says that the aim of management now is to maximise pasture growth rates so that there is adequate pasture on hand by the start of mating.

“Past DairyNZ research showed that to maximise pasture growth rates grazing needs to occur at the two and a half to three leaf stage. As temperature drives leaf emergence, two and a half leaf stage grazing interval will be longer than 40 days given the current conditions."

“Using supplements now can be profitable. If the milking cows are grazing to lower than 1500 kg DM/ha common supplements (PKE, grass and maize silage) will be profitable to feed. If the milking cows are grazing to 1200 kg DM/ha nearly all supplement will be profitable to feed,” says Ms Hedley.

There are a number of other tactics farmers can choose if faced by low pasture covers:

• Hold a 30 day rotation for as long as possible. Aim for 7-10 September or at least to 1 September before going to your fastest round
• Get sufficient supplement on hand to fill the feed deficit for at least the next 10 days
• Graze no lower than 1400 kg DM/ha; this may mean standing milkers off if you don’t have the supplement. It is better to do this now for 10-20 days than have cows underfed at mating
• Feed supplement to get grazing residuals to 1400 kg DM/ha minimum. Aim for 1500 kg DM/ha
• Apply nitrogen now so when conditions are favourable for growth N won’t be limiting i.e. have 50 kg N/ha on all paddocks grazed by the cows since calving
• Consider using giberrellic acid, following the application recommendations, on covers greater than 1200 kg DM/ha, applying within five days of grazing
• Feeding dry cows up to 80 per cent of diet in supplement and grazing one paddock to 1000 kg DM/ha will have little impact on total farm growth
• Do not graze dry cows behind milkers
• Back fence – every day of growth counts.

“The key to getting supplementing right is monitoring,” says Ms Hedley. “At this time of year pasture growth can increase quickly."

“Farmers should be monitoring their grazing residuals with a plate meter several times each week, and average pasture covers weekly, looking for opportunities to take some supplement away from the herd and offering increased areas of pasture."

"Grazing residuals of 1300 kg DM/ha currently could quickly become 1500 during a single week. If this happens supplementary feeding becomes less profitable and if continued at high levels becomes an expensive way of generating surplus grass.”

TheCattleSite News Desk