We recently had a webinar discussing what we need to do with ewes to get them ready for breeding season. Often rams are forgotten. Sperm is being developed six weeks prior to breeding so fertility checking rams at breeding time is ok, but if they haven't been handled correctly the previous six weeks they probably won’t check out that well.
In my own flock (where a single sire is used) I prefer to rotate rams, over fertility checking as insurance that ewes are bred. A successful fertility check doesn't guarantee conception. The first consideration is a condition, not overly conditioned, but need to be in good rig and maintained that way. Testicles need to palpated for size and abnormalities. Rams with soft testicles, undersized, abscesses or hernias need to be culled. Rams should be wormed and if external parasites are a problem may be poured with 1% permethrin which will help some for flies as well.
Ventilation and shade are extremely important. Rams shouldn't be in long fleece and shearing should be done at least two months prior to breeding. There is a difference in breeds and seasonality is involved. Black face rams are less tolerant of weather and more seasonal than Katahdins. This is just one example of the difference between breeds and there are differences within breeds. Yearling rams should be able to handle 60 ewes, a mature ram lamb 25 ewes and mature rams from 25 to 60 ewes depending on condition. There are exceptions. I once turned a yearling ram with 160 ewes in a pasture in September for one heat cycle. 150 lambed and we lambed in three places instead of one. Later he was champion ram NAILE.
