Our family farm consists of 50 acres, all in permanent pasture and fenced for rotational grazing. Pastures include: Trefoil, red clover, alsike, bluegrass, timothy and more. We typically run a commercial white face flock of ewes that ranges in size between 70 and 100 head of breeding stock. The ewes are mostly Dorset/East Friesian. We also buy week old Holstein calves from neighbors and graze some steers in conjunction with the ewe flock. We have a donkey with the ewes for predator control. Ewes are lambed on pasture in June. The flock never sees the inside of a barn, but is out all winter, grazing stockpile under snow or big round bales set up on pasture. We expose ewe lambs to lamb at a year of age. Ewe lambs are managed separately from the flock, though also, for the most part, on pasture. Market lambs combing off pasture are fed out with grain.
Prior to receiving this grant, we rotationally grazed approximately a half dozen years. Since this grant, we have however, become even more low input and intent (and successful) at improving our pastures. We still do not water our ewe flock in the winter, and we do not water them spring, fall and even summer when there’s ample rain and heavy dews.
PROJECT DESCRIPTION AND RESULTS
The goal of this project is to see if ewes consuming snow as their sole source of water perform as well as those given free choice access to fresh water, and to see how prolificacy and lamb size are impacted as well.
A flock of 66 commercial white face ewes, that had been on pasture until December 25, 1996, were randomly divided into four groups: adults on water, adults on snow, yearlings on water and yearlings on snow. Rams were turned in on the initial January 15, 1997 weigh in.
It should be noted that the yearlings were light in weight and low in condition score as a result of lambing at 12 months of age and then running too long with the adult ewes after their lambs were weaned. The yearlings were thus fed second crop hay free choice and one pound of corn per day until the March 6 weigh date, at which time they were added to the adult ewes and fed the same.
Adults were on free choice big round bales which tested at 10.6% protein and 86 RFV. All of the sheep had mineral available at all times.
Sheep were weighed and condition scored at approximately 25 day intervals during this 75 day trial. They were ultra sounded for pregnancy. Those results were compared to the actual number of lambs born. Lambs were also weighed at birth and groups compared.
Adults will be compared to adults and yearlings to yearlings, as they were fed differently. What’s more, yearlings are still putting on some growth to reach mature size.
The average weight gained per adult ewe on water was 26.5 pounds, while the average for those only receiving snow was 20 pounds. Yearling ewes on water gained 31 pounds on average, compared to 22 pounds for those on snow. As for body condition score, adults watered gained 0.44 point, compared to 0.29 for those on snow. Yearlings on water gained 0.50 condition points, while those on snow gained 0.21.
However, a great deal of these differences in gain were offset by the ewes’ initial body condition. All groups finished with close scores – adults on water with a body score of 3.28 versus 3.24 for those on snow. Yearlings on water finished lower at a body score of 3.30, compared to 3.32 for those on snow.
The actual lambing percentages were very close to what the ewes had been ultra sounded to deliver. In three of the groups, there was only a one lamb difference between ultra sounded and lambs born. The remaining group delivered the exact number of lambs the ultra sounding had predicted they would.
However, large differences surfaced in lamb weights. The average weight of lambs born to adults on water was 10.5 pounds, while it was 9.36 pounds for adults on snow only. That’s a difference of 1.14 pounds per lamb born, with the watered ewes delivering the heavier lambs. Yearlings showed an even more dramatic difference. Lambs born to those on water averaged 9.83 pounds, while the lambs of yearlings consuming only snow averaged 8 pounds a piece. That’s a difference of 1.83 pounds per lamb.
Clearly, lambs born to ewes given access to fresh water will weigh more at birth than those over wintered on snow alone. Ewes will also gain more weight when they’re watered. No adverse impact on the health of either ewes or newborn lambs was noted when the ewes relied solely on snow for their water needs. All ewes made steady weight gains. All ewes’ condition scored well at the end of the trial. No significant difference in pre lambing mortality was noted (lambs lost between ultra sounding and birth). Lamb weights were acceptable in both groups, but I wouldn’t want to drop below that 7 to 8 pound range.
Because ewes relying on snow for their water needs could gain weight and condition and produce a high percentage of healthy although lighter weight lambs, I feel relying on clean snow as the sole source of water is a viable, humane option for reducing labor during the winter. I also believe that some, if not all, of the resulting weight differences could me made up by feeding better quality hay. The quality of hay fed during this trial was fairly low.
A few notes: four yearling ewes were dropped from the study – two from the watered group, two from the group on snow – because they were unable to gain weight and maintain condition, for unknown reasons. They did, though, lamb and are doing fine now. It’s speculated they weren’t aggressive enough at the feeder, as is sometimes the case with young ewes.
This study took place in the first half of gestation, which is for the most part, a maintenance period. When the trial was over and the snow melted, the ewes were turned onto leftover pasture and given access to bales and water. They were on lush spring growth through lambing, which started June 7, 1997. No grain was fed in the last trimester. No ewes had ketosis. Ewes lambed out on pasture and were not jugged up in the barn.
Ewes were not forced to clean up every stem of the relatively low quality hay fed in this trial. Nor were they allowed to waste it. If ewes self fed big round bales are expected to clean up the hay from the start, they will consistently clean it up. If allowed to be picky, they’ll force themselves to get pretty hungry before they eat the coarser stems. However, once they make up their minds to eat the stemmier leftovers, they remain better eaters.
To tell others about our project we held a field day (November 15) which was well attended by sheep producers in Central Wisconsin. Advance publicity for the field day was sent to the 3 statewide farm newspapers, the local newspapers, county Extension offices in the area (which included it in their newsletters to farmers), and sheep producer organizations mostly in central and northern Wisconsin. Most, if not all of the final research results were printed up and handed out to producers at the field day.
We also sent the final report to the UW sheep specialist. Brain was invited to be a guest speaker on the University’s statewide Educational Telephone Network (ETN) winter sheep production series. On the sheep ETN, he talked about the project, SARE in general, and shared results and no winter watering comments with hundreds of producers listening to the ETN out in their individual counties. As a result of that ETN appearance, one of the statewide farm newspapers, the Wisconsin State Farmer, covered the story in the paper.
The research final report was also publicized in it’s entirely, as written by Brian, in sheep!, and the Shepherd (both national sheep magazines) and the Farmers Digest (a national general farming magazine).