Breeding season has kicked off on many farms, and with that farmers using a stock bull are reminded to monitor their bull.
Assuming an average gestation length of 280 days, a cow served on May 1, 2024, would have an expected calving date of February 5, 2025.
With the wet spring experienced this year, some spring-calving herds are considering delaying their breeding season to delay the commencement of their calving season next spring but careful consideration should be given before taking this step.
In a recent post on the Teagasc website, Teagasc drystock advisor Patricia Lynch outlined 10 factors for farmers to monitor to ensure their bull is performing correctly:
- Bull fertility check: A bull’s fertility status can change, from year to year. It is good practice to have a fertility test carried out on the stock bull prior to start of breeding season. It is estimated that 25% of stock bulls are sub-fertile. The cost of the test is very low compared to carrying empty cows for the summer and test results are available to farmers before the technician leaves the yard;
- Body condition score (BCS): A bull must be able to maintain body condition (ideally, BCS 3). The bull must be physically fit to serve cows for 12 weeks and have a long working life in the herd. Where farmers are buying a bull, farmers should find out from the seller what level of concentrates the bull is being fed and what vaccinations he has received;
- Health: Consult your vet for advice on the health of the bull. Remember a young bull in his first season should serve no more than 20 cows;
- Nutrition: It is important to avoid sudden changes in diet and not to over feed the bull as this can reduce fertility and can also lead to feet problems. The bull needs to be fit but not over-fat;
- Visual check: Before the breeding season, check the bulls’ feet and legs are good and take remedial action, if required, well in advance of the breeding season;
- Observe: Watch the bull working to check he is serving cows correctly;
- Rotate: If possible, rotate bulls or scan cows early so that an infertile bull or sub-fertile bull can be identified early;
- Records: Record when you see a cow being mated and watch for signs of cows coming on heat repeatedly;
- Issues: If a large number of your cows are repeating, you need to take action to find out what is wrong. You must be prepared to start using Artificial Insemination (AI) or if you have a second bull with another group of cows, he may be utilised to serve more cows;
- Pregnancy scanning – When it is at least 35 days since the last cow in the herd could have been served then you should consider scanning the cows. It offers many advantages.
Finally, it can never be emphasised enough that bulls are dangerous animals and caution should always be exercised when working near bulls.
Bulls (or cows for that matter) that show any signs of aggression should not be given a second chance and should be sent for slaughter.
When entering a field or an area where a stock bull is present, farmers should always have an exit route planned. Bulls are unpredictable animals and are particularly so during the breeding season.