Autumn-calving herds will be coming close to the start of the breeding season. With cows housed, there is a good opportunity to use more AI in autumn herds to improve calf quality and performance.

Use of AI offers herd owners the opportunity to use different sires to suit different cow types. This eliminates the need for multiple stock bulls on-farm, which is less feasible for smaller herds.

Different sires can be chosen to breed calves to suit different markets. AI also allows suckler farmers access to the best cattle genetics available.

Where cows are served by natural service, the stock bull will do the heat-detecting and serving for you.

However, when using AI, you will have to identify cows in heat so that they are served at the optimum time to improve conception rates.

This is easier said and done. While other factors, such as cow condition, diet and herd health, will impact on conception rates, there is little point in trying to AI cows if you are not prepared to spend time heat-detecting.

Following the outlined steps for heat-detection will help to get more cows bred at the ideal time and improve conception rates.

1. Increase time spent observing cows

Like anything, the more time you put into it, the more you will get out of it. You should be observing cows three to four times daily during the breeding season.

Each period spent observing cows should last for 20 to 30 minutes. While some cows show strong heats, others will not. Therefore, the more time you spend observing cows, the better.

Cows housed on slats can have shorter standing heats of one to two hours. This makes it harder to pick up these animals if your time is limited by working off-farm.

Using heat-detection aids will help to identify cows in heat if your time is limited.

2. When to observe

Morning and evening are the most obvious times to watch for cows in heat. Both periods also tie-in with the am-pm rule, where a cow in heat in the morning should be inseminated at night and vice versa.

However, it is also worthwhile spending a period of time heat-detecting in the afternoon and again late at night.

This should be carried out at a time when cows will have settled after their daily feeding routine, when fresh silage or meal is offered, as animals will be exhibiting their normal behaviour.

Similarly, if you are monitoring cows in the morning or evening time, do not automatically start pushing in silage as soon as you enter the house.

This will disturb cows from their natural behaviour and make it harder to pick up the cows with short standing heats.

3. Use heat-detection aids

There are several aids for heat-detection and they range in price and practicality. How effective they are depends on how often you are checking cows and using them correctly.

If you are checking cows three to four times per day, then some aids will offer little benefit.

Heat-detection aids work best when time is limited with off-farm employment, multiple enterprises or multiple stock groups. They also work well on animals that show weaker heats.

You still need to be monitoring animals at least twice daily to identify which cows have had a standing heat, so that they are served at the optimum time to increase conception rates.

4. Restrict suckling

Restricting the suckling activity of calves to twice per day can help to bring cows back into heat again after calving. It also has a positive effect, with cows tending to show stronger heats.

Calves should be restricted to suckling to a short period in the morning and again in the evening from around 20 days after calving.

Winter housing makes this option much more practical, as calves can be locked away from cows in an adjoining creep area during the daytime and at night.

5. Record heat and insemination date

Record the dates of all heats and inseminations, that way it will be easier to monitor cows for any repeat breeding activity, should they fail to hold to service.

Keep a close eye for repeat activity from around day 17 onwards after inseminating the cow.