The rams are in with the ewes and another successful breeding cycle is well under way, or is it?
Andrew Sawyer of Alnorthumbria Vets of Alnwick says: “It’s important to keep a check on progress and the first indicator is the raddle marks on the ewes.
“Ideally the ewes should have tupped quickly with all ewes covered in the first 17-day cycle.
“Poor mating results can be split into three categories; ewes not cycling, fertilisation failure and failure to conceive or maintain early pregnancy.”
One reason for ewes not cycling, which the vets in Mr Sawyer’s practice meet on most years, is that they are already in lamb to a chaser lamb or the neighbour’s tup.
Breed can also have an effect, he warns. Don’t expect Blackies to be cycling in August but Suffolks or Dorsets should be no problem. Ewe lambs and gimmers are normally slow to start.
Prolonged stress caused by very poor weather may delay activity, and if the ewes are in very poor condition they will not come to the tup as readily. High levels of red clover in the pasture may contain oestrogens that prevent ewes cycling normally.
Mr Sawyer added: “Fertilisation failure occurs if you have used unsound rams.
“Hopefully you and your vet have checked this all before use but they can and often do go wrong during the breeding season.
“Inappropriate ewe-to-ram ratios can also lead to ewes not being covered. A fit but not fat and completely sound ram will serve a lot of ewes, but an overfed ram fresh from the sales and unable to walk far will manage a lot less.
“Too extensive an area for mating may lead to ewes being missed but they are pretty good at searching out a ram if in heat.”
Failure to conceive or maintain pregnancy is the area of most concern from now till scanning, he said.
If the ewes look to have been covered well from the keel marks and don’t live up to expectations on scanning, call the vet in to investigate before the empty ewes are sent to the mart. Those ewes may yield important information into why there is a problem.
Severe under-nutrition due to heavy snow or shortage of grass or other feed is one reason for ewes to reabsorb foetuses. Low protein status due to a high parasite challenge, particularly with fluke, Johne’s Disease or a poor diet, also leads to reabsorbing foetuses.
Persistent stress is an issue. Mineral deficiencies of selenium and iodine can lead to low scan rates. Infections most likely are Toxoplasmosis and Border Disease.
Mr Sawyer concluded: “If more than 2% of your ewes are empty at scanning, or your scanning percentage is lower than expected, getin touch with your vet to discussthe problem before you cash in the barren ewes.