4 April 2011

3 minute read

A tight calving pattern will:

• Make management easier;
• Have all cows at the same stage of the breeding cycle;
• Make feed and grazing management easier;
• Allow batching of management tasks such as disbudding, castration, tagging, vaccinations, worming, pregnancy diagnosis etc.
• To optimise the timings of the above tasks;
• To improve management during calving;
• To give more even batches of calves for sale.

In order to have a tight calving pattern you have to want one and be prepared to work to achieve it. Everything has to be managed optimally to maintain a short calving but this is more than offset by the reduced work once it is in place.

Starting with your bulls; they need to be fit not fat so for spring calvers leaving the bulls out overwinter with a bit of mouldy hay will often leave them too little time to recover before their work begins. Turning a fat young bull out straight from the sales often results in a rapid loss of condition and the bull failing to work. Conformation needs to be good.

A bull with huge hind quarters that has weak hocks and can’t serve his cows is no use to anyone. Over grown and infected feet need sorting out well before the bulling period as they can affect fertility. Get your Veterinary Surgeon to check the fertility of your bulls. This will pick up those producing poor semen and some physical defects but you still need to see the bulls working. A bulls ability to serve is affected by his enthusiasm or libido and a range of physical conditions such as corkscrew penis, deviated penis, adhesions, persistent frenulum ,ruptured penis as well as lameness caused by infection, arthritis or osteochondritis.

Moving onto your cows again maintaining or improving condition is probably the most important factor in good fertility and a tight calving pattern.

Thin cows are unlikely to cycle and if they do they have less chance of holding in calf. Fat cows are more likely to have calving problems which will leave them less fertile. Nutrition is the main factor for your cows they need adequate energy to cycle.

A correct protein level to balance the energy is also important as are adequate mineral levels. Copper and selenium in particular are important in fertility though other trace elements such as iodine are relevant. Ease of calving plays a big factor in subsequent fertility and without high levels of fertility a tight calving pattern is not possible.

A cow that easily by herself produces a small to medium sized calf after a short gestation period will have a much better chance of being ready for the bull at the start of the mating period. There is much less chance of damage or infection when compared to a cow that holds onto her calf over 300 days and then struggles to calve. So breed selection and selection within a breed for desirable calving characteristics are very important if you want a tight calving pattern with little wastage.

There are infectious conditions to control to maintain optimum fertility. You can vaccinate to protect against Leptospirosis, Bovine Viral Diarrhoea (BVD), Infectious Bovine Rhinotracheitis (IBR) and in some circumstances Campylobacter or you may improve biosecurity to keep the diseases out once you know you have eliminated them.

The Scottish Agricultural College runs a Premium Cattle Health Scheme which monitors disease status and can include Johnes another disease that can reduce condition and fertility in infected animals. Parasites will also have an effect on condition and performance so fluke, worms and lice should be monitored and treated accordingly.

Maintaining a tight calving pattern can bring great benefits but to achieve one requires some effort. Effective health planning with your vet should make the task easier. It is possible to get good conception rates in a six or seven week bulling period if everything is performing to its optimum.