July 2023
Options to influence your lambing season
Teaser Ram
Used correctly a teaser ram can shorten your lambing periods up to 10 days in length and is cost-effective for larger flocks. Shortening your lambing period helps to manage lamb groups more efficiently, (vaccinations and coccidiosis treatments as lambs are closer in size and age). It can reduce staffing and labour costs as well as potentially helping you to catch the spring markets.
Please make sure you have the capacity to deal with the number of ewes lambing at the same time. A teaser ram is a vasectomised tup. The teaser needs to be prepared at least six weeks in advance to make sure he is no longer fertile. We can perform the surgery on farm or at our Ludlow branch. We strongly recommend a laboratory examination of the tissues removed as well as semen testing the teaser rams annually. Nature has a strong will to repair itself.
Synchronising
A combination of a progestogen sponge and PMSG injection is used. In some animals, PMSG will also increase the ovulation rate, resulting in a higher lambing percentage. The lambing season can be kept very compact which can be a great advantage for small holders. It also allows the flock to be lambed in two distinct batches which can be useful if shed size is limited.
A ram to ewe ratio of 1:10 will be needed for synchronised ewes. Ewes should be at a condition score of 2.5-3.5 to maximise efficacy.
Melatonin
Melatonin implants are another option for advancing the breeding season. They can bring forward lambing by two months, but don’t synchronise the ewes, so very high ram to ewe ratios are not necessary. The hormone implant is administered at the base of the ear around 35 days prior to ram introduction to the flock. It works by releasing a small amount of melatonin similar to what the ewe produces naturally as daylight hours decrease. You will need to make sure that any ram is removed for at least 7 days prior to implanting.
Bull breeding soundness examination including semen testing
Why test?
We don’t only want to identify sterile bulls (which are totally incapable of getting cows in calf) but also sub-fertile bulls. Sterile bulls are rare and relatively easy to identify as your cows will keep come bulling every 21 days. Sub fertile are the expensive ones as they might get most of your cows in calf but take much longer. Having a spread-out calving pattern increases the period of time you need to monitor the herd closely but also creates a wide variation in calf ages.
A variation in calf ages might impact the marketability of these calves, make their management more difficult, but more important impacts their health. Pathogens (bacteria and viruses) build up over time and are usually worse at the end of the calving season. The longer the calving season the bigger the problem. Also, older animals will pass diseases like pneumonia on to younger animals. On dairy farms, sweeper bulls are normally confronted with the most difficult cows to get in calf. They need to be as fertile as possible.
Who to test?
Ideally, you test your bull annually. Good fertility in one year does not guarantee good fertility in the following year. For example, an injury or infection, which is not obvious to you, can impact fertility. It can be an old man’s problem. Bull’s fertility will start to decrease at 6 years of age. We recommend strongly to test newly purchased bulls as soon as possible or even before purchase. If you keep multiple bulls, the older bulls (more likely to be sub-fertile) are most likely to be more dominant and keep the younger bulls from mating. Please ask Richard for more information.