Farm Ireland
Independent.ie

Friday 21 July 2017

Now is the time to review the health and fertility of your cows

Dairy

Mary Kinston

By now, most farmers have started to close up their grazing platforms for next spring. Effectively, the remaining grass is being rationed out in this final grazing rotation.

Autumn rotation plans or feed budgets are available from many sources and are helpful in this process. Culling and drying-off decisions are very much on the table as farmers aim to manipulate their feed demand in line with autumn closure, especially where the superlevy is a risk.

The winter accommodation is also getting its final overhaul and consideration should now be given to how animals are going to be batched up into wintering mobs based on age, size and condition in order to reach body condition score targets at calving and liveweight targets of maiden heifers for next spring.

For the spring-calving herd, farmers may have taken the opportunity from August to October to make a final assessment of the herd's reproductive success by scanning the cows and heifers to confirm age and pregnancies, as well as to determine the empty cows within the herd.

Scanning results can be the high or low of the farming year, and on the ground there has been a mixed bag from excellent to concerning empty rates.

When discussing results among fellow farmers, remember to consider how long the cows were mated for as this substantially influences the final empty rate. The longer the mating period is, the lower the number of empty cows.

However, at the same time, this will result in a higher percentage of late calvers so the six-week in-calf rate is a far better guide. The targets for the good, bad and the ugly are suggested in table 1 (above).

Calving spread can have a huge bearing on your final empty rate and a high number of late calving cows combined with a shorter mating season as a consequence of quota concerns can result in a high number of empty cows, although this should benefit the following year's mating.


If you are concerned with your empty rate, go through your empty cows and look for trends and ask questions.

Was she a late calver? Was she cycling at mating or treated as a non-cycler? Did she have any health issue such as bad calving, retained cleansing, milk fever, lameness or mastitis?

Was she a carryover or are they mainly heifers? What is your disease status? Is there any mineral deficiency?

Dealing with infertility issues is not an easy process, but building up a picture of information may help you and your vet identify areas which need further investigation or management areas for improvement.

Considering the pregnancy rate of your in-calf heifers can also add some light as top farmers will achieve 75pc conception in the first three weeks of mating and 92pc in the first six weeks.

If these figures are less than 65pc and 85pc respectively then it might be worth reviewing your calf and heifer management, the date you started mating, insemination technique and heat detection if AI was used, and bull management.

October to December will see many culling and dry-off decisions being made on farms.

Unfortunately, in many cases culling decisions will be determined solely by the fact that a cow was empty and the opportunity for selective culling is often limited.

However, where quota is limiting and cow numbers for next year are being debated, or where mating results have been good, there should be the opportunity to make selective culling decisions and improve the profitability of the remaining herd. Table 2 (above) provides a guide to efficient culling practise.

Dr Mary Kinston is a farm consultant based in Kerry. Email: mary.kinston@gmail.com

Indo Farming