Management Hints JUNE 2018 The spreading rate will be 1,500-2,500 gallons of diluted slurry per acre. X Very heavy applications result in run-off or caking on the surface; X This will save 8-13 units of N per acre. Do not spread within 30-40 yards of wells and open waterways. X Minimise risk of pollution. Do not spread when wind is blowing towards local householders. X Some farmers love annoying their neighbours, but don’t; X Use downward spreading splash plates or trailing shoe; X Turn off the vacuum tanker immediately when tanker is empty. Again, be very careful, while agitating, as the gasses will kill without warning. X Too many road accidents happen as a result of no warning signs or muck on the road and/or involvement of very young tractor drivers; X Talk about these safety issues in advance. Spread the slurry immediately after the silage is cut. X N should be spread five to seven days later; X You will lose N to the atmosphere if spread near the slurry spreading date; X Anyway, there is no rush as there will be no growth for 7-10 days. Spread lime on 'bare' silage fields earmarked for grazing and other bare grazing fields that need lime. X Generally, all fields need 2 tonnes (t)/ac of lime every three years. In-calf for 2019: check and act two to three seconds, the chances of not seeding these cows bulling now is very high. You must increase your heat observation efforts: X Tail paint, or such aids, are now more important than ever and should be topped up every three to four days; X A vasectomised bull, if you have one, should now be introduced; X He will be effective without a chin-ball if cow numbers are not too high; X Many farmers are now using computerised devices during this period to ‘help out’ and they have merit because it is now very difficult to identify bulling cows; X Use previous service dates, from the ICBF report, to guide you to expect certain cows. If more than 25 per cent of cows are repeating, you have a problem: X Look at the repeats and analyse the situation. Bull late calvers at 35-40 days after calving with a young test bull (easy calving with a minus 7+ days for calving interval). The same principle applies to repeat artificial insemination (AI) bulls being used. Some farmers with infertile herds are scanning cows served more than 35-40 days to confirm pregnancy – if a cow is in calf on that date she has a great chance to stay in calf. This allows you to use your vet to take remedial action for those cows not pregnant or with a weak pregnancy. Question: How long should I use dairy AI? Each missed heat now results in €250 per cow loss: X She will be a late calver; X She may be culled if she doesn’t go in calf before the end of breeding season, leading to losses of €800-1,000; X Check your Irish Cattle Breeding Federation (ICBF) fertility report for 2017 to see if you have ‘long repeat intervals’. A figure greater than 15 per cent in this box indicates that you are missing heats. We are now in the most difficult part of the breeding season: X It is more difficult to identify bulling cows; X Bulling activity is now only one-fifth of what it was four to five weeks ago; X Fewer cows are bulling, therefore, there is less bulling activity and, as some cows are only mounted five or six times (the average is 10), with each mount only lasting Farmers must use five straws for every heifer required. X A 100-cow farmer will need 25 heifer calves; therefore, use 125 dairy AI straws. X Farmers must keep using AI until that number of straws are used in the season. This includes repeats; X If the farmer intends expanding or has mastitis, lameness or other health issues, he must use more AI straws. Choose your AI bull now to ensure a shorter calving period: X He must have an Economic Breeding Index (EBI) of €270, over €120 for fertility and 0.15 per cent improvement in percentage fat (F) and protein (P). X He should be minus seven days or greater, on calving interval, at this stage of the season; X And, he must meet whatever other criteria you have set for the herd. After 9-10 weeks breeding, some farmers scan the cows for pregnancy: X This is a good idea as you can act on the results under veterinary supervision. When the correct number of dairy AI straws have been used, introduce the stock-bull. 48