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Husbandry

Grazing

Conditions are excellent and most farms have enough grass to have cows out full time with no need to feed meals. Soil temperatures are rising above 8 degrees and there is plenty of sunshine. Expect growth to take off. Growth at Moorepark is 56 kg DM/ha/day - the norm is 51.

Many farmers have finished the first round. Heavy covers are being skipped. They are closed for silage or grazed by dry stock. They can be brought back for grazing later if grass runs short.

Be careful before using milkers to graze out heavy covers. You could end up with too much grass ahead. The best approach is to measure farm cover. A total cover of about 2,000 kg DM/ha is sufficient if growth is equal to demand. If you are above this cover, then take out the heaviest paddocks.

Grass is still short in some farms. Frosts have hit growth. This is a problem with low covers. If you are in this position, find out why you have a low farm cover. Was it late closing last autumn, inadequate fertilizer or heavy grazing pressure in the first round? Farmers, who have plenty of grass started closing paddocks in early Oct, spread N in Jan, started grazing in Feb and have just finished the first rotation. It can be done!

Condition score

Spring calvers: Cows that are over 2.75 CS at breeding will have pregnancy rates to first service of 64-72 per cent after six weeks of AI.

Ideally, you should CS all cows when they are standing in a crush. Condition score from the side. Cows must be felt by hand. Use the flat of the hand. If condition is static or falling you have to increase feed intake. The cheapest feed is always grass. If you have enough grass, allocate more to the milkers and clean out paddocks with dry stock. Block grazing every 12 hours is not recommended because heifer intake is hit.

Aim for 36-48 hour grazings. Give more than enough for the first 2-3 grazings and clean out the paddock in the last one. That way, intake is restricted for only one grazing in every 3 or 4.

Many farmers have grazed tightly (1,300 kg residual) in the first round. The regrowths are very leafy and very high quality. So, in this round, graze down to about 1,500 kg to achieve high intakes of high quality feed.

Autumn calvers: Sept/Oct calvers have 2-3 months to go before drying off. They should be gaining condition to reach score 3-3.5 at drying off in July/Aug.

Measure the CS of all autumn calvers. Cows that need to gain CS should either be dried off early or fed meals depending on quota situation.

Lepto

Vaccination against lepto is a must. Some 80 per cent of unvaccinated herds are infected. Trials show that infected cows had low conception rates of 34 per cent. Vaccination increased CR in another trial from 29 to 49 per cent.

There is time to vaccinate cows and bulling heifers. This should be done at least two weeks before the breeding season begins. Vaccination closer to breeding can reduce CRs. This may be due to the stress of vaccination rather than the vaccine itself. So, it makes sense to minimise all stress as you enter the breeding season.

Don't forget to vaccinate autumn-born heifers. There is also some evidence to suggest that spring-born calves should be vaccinated early in life before they pick up infection.

Bulling heifers