Friday, December 9, 2011

Always More to Learn!

I'm beginning to realize that raising sheep will involve a lifetime of learning.  Each season - each day, in fact - offers new lessons (provided I'm paying attention).  As first generation producers, we've learned some of these lessons the hard way; others we've learned from mentors throughout the sheep industry.  In turn, we try to share the lessons we've learned with others (through workshops, writing and other avenues - including this blog!).

Sometime in the late fall every year, we bring the ewe flock into the corrals to trim their feet in preparation for winter.  Usually, we've done this soon after we pull the rams from the flock in mid-November.  This year, we waited several weeks - seems that any stress on the ewes in their first 16-18 days of pregnancy can cause them to lose their fetus(es).  We're hoping that delaying this work by three weeks will increase our lamb production.

We've been battling footrot - a fungal infection of the foot - since we started in commercial sheep production 6 years ago.  This disease can cause significant production losses.  Sheep with sore feet don't move around much, sometimes barely grazing enough to maintain themselves.  Since lambing rates are directly related to nutritional intake prior to and during the breeding season, ewes that aren't eating enough do not have as many lambs.  In past years, we've relied on the FootVax vaccine to help reduce our footrot problems; however, the vaccine was pulled from the market about a year ago.  Since then, we've relied on regular trips through a zinc sulfate footbath.  We've also tried to remove the ewes with the worst problem (or the least resistance) from our flock - and we haven't kept the offspring from these ewes, either.

On Wednesday and Thursday this week, we trimmed the feet of all 230 ewes and ewe lambs.  Our flock includes about 85 cross-bred "mule" ewes (a cross between a Bluefaced Leicester ram and a whitefaced female) and about 105 whitefaced ewes (including Border and North Country Cheviots, Dorper and Dorper crosses, Dorsets, Coopworths and about 35 yearling Columbia ewes we purchased last spring).  The results were informative!

Of the mule ewes, we had fewer than 5 individuals with any sign of footrot.  Most of these ewes didn't show symptoms of an active infection - they appeared to have fought it off.  Of the whitefaced ewes, those that had been in our flock for more than a year were similarly healthy.  We noticed that the whitefaced ewes with black feet (the Cheviots, primarily) were especially resistant to the strain of footrot we have.  On the other hand, the new Columbia ewes were almost universally infected.  We had purchased the Columbia ewes to evaluate their potential as the whitefaced breed in our three-tier breeding system.  Based on their susceptibility to footrot, we've ruled out this breed.  We did put all the ewes through the footbath, and we expect the foot problems to heal in the next week or so.

Waiting for the ultrasound machine!
Sami reading the ultrasound scan - this ewe is bred!
For the first time this year, we also used ultrasound to check on our conception rates.  We selected 20 percent of our ewes at random and Sami scanned them.  We had 8 "open" (or un-bred) ewes, which suggests a conception rate of about 80 percent (on the low side of normal).  All but one of the open ewes was a maiden ewe (being bred for the first time).  Three of the open ewes were in our Bluefaced Leicester breeding group, while five were in our terminal breeding group.  If these percentages hold for the entire flock, we have about 35-40 ewes who are not bred.  Based on this finding, we put three rams back with the flock.  This will hopefully give us a higher conception rate and will provide us with some later born lambs.  Since we want ewes that breed early in our breeding season, we won't keep any of the female lambs out of this late breeding.  The fact that most of the open ewes where first-timers suggests that we may want to do something a bit different with our pre-breeding nutritional program next year.  We also had a ewe-to-ram ratio of about 40:1 this year.  We'll purchase more rams next year and reduce this ration to 25 or 30 to 1, which should also improve the conception rate.

This morning, the dogs and I moved the entire flock to a neighboring property about a mile away.  I always look forward to this time of year - we get a brief break in our work around Christmas.  We'll contemplate what we've learned this year and what we'll do differently next year!
Passing the persimmon trees.
Fresh grass!
Heading out for new pasture!

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