Scientists Test Use Of Raised
Pens For Quality Production

By Colleen Schreiber

SAN ANGELO — Producing superior quality lamb and wool is becoming more and more critical for sheepmen serious about making a living in the business today. Being paid for that quality is an entirely different issue.

Researchers at the Texas A&M Research and Extension Center here, dedicated from the start to the advancement of the sheep and goat industries, continue to initiate research to answer concerns and questions directly applicable to producers throughout country. One such project now in its second year is a raised floor feeding system for lambs.

The use of a raised floor for feeding animals is certainly not a new idea, but a team of researchers here felt it might hold promise for the sheep industry, particularly for producers trying to find a niche market for premium lamb and wool products.

Thus in 1998, Texas A&M University research nutritionist Dr. Ed Huston and wool and mohair specialist Dr. Chris Lupton, both based at the research center here, set out to test whether a raised floor feeding program could produce superior lean lamb carcasses and high quality wool.

The researchers presented their preliminary results at the recent 26th annual Sheep and Goat Field Day at the Texas A&M Research and Extension Center here. This year's field day was dedicated in memory of Royce Jones, San Angelo Standard Times agricultural writer.

The team reviewed some of the advantages they expected to see using such a raised floor system. Those included a clean, healthy environment, reduced exposure to internal parasites, no predation, and reduction in energy expenditure because the animals don’t move around much. They also expected to show improved comfort with an environment that was cooler in the summer and warmer in the winter, and they hoped for cleaner fleeces, more uniform and consistent fibers, pelts and meat, and seed-free, consistent manure.

The challenge from the outset, Huston told listeners, was to design a system where feed could be easily delivered; that it wouldn’t be dusty, to keep animals healthy and thriving; and to deal with the manure problem.

In 1998 the researchers conducted a preliminary study to evaluate the system, particularly the delivery system as well as the feed they opted to use. Huston said the feed, oat hay ground in an on-site tub grinder, was chosen because they felt it had the right density of nutrients to accomplish their goals.

"We wanted a feed that would provide a slow but steady rate of gain so that at 14 months of age of these lambs would have a lean carcass and at the same time provide them with the time to grow a high quality 12-month fleece."

Ninety-four lambs went on feed at three to four months of age and were on the floor from June through February. They were shorn at just over 12 months of age.

In terms of wool the targets were a grease fleece weight greater than eight pounds; yield greater than 60; fleeces with no vegetable matter; staple length greater than 3.75 inches; and fiber diameter less than 19 microns.

In 1998 the researchers hit some targets and missed others. Grease fleece weights were 7.9 pounds, but Lupton pointed out that there was quite a bit of variability, from 5.1 to 11.7 pounds. Yields averaged 54 percent and ranged from 42 to 61 percent.

"The main thing was that we wanted to produce fleeces with no veg at all, and we expected we could on this floor," Lupton said, "but using this particular feed, the ground hay, we got a lot of veg and I'm not even going to report those figures."

Staple length, he said, was just under the targeted 3.75 inches, and fiber diameter ranged from 19.6 to 20.4 microns.

"Overall, the lambs on the floor stayed fairly fine and uniform," Lupton concluded.

Huston presented the lamb results. The lambs were sold about six weeks after they were shorn at about 14 months of age.

"We wanted to start with a 70-pound lamb and put about 65 pounds on," he told listeners. "We started with 68 pound lambs. To accomplish our goals we needed to gain .22 pounds per head per day. Ours were a little below that and ranged from .14 to .31 pounds per head per day. We learned something, and we've tried to correct that for the second year."

The targeted carcass weight recommended by packers was 65 pounds. Lambs on test fell short of that, averaging 57 pounds. Researchers were shooting for .25 inches of backfat, which would be a yield grade 2 lamb. Fat cover on test lambs was just a little less than what researchers wanted.

Furthermore, targeted quality grade was Choice for all lambs, but in the end only 68 graded Choice. Four graded Good, but where they took the biggest licking was the 22 "spool" lambs, meaning their break joints wouldn't break.

Researchers learned something valuable, however, in that 21 of the 22 spool lambs were ewe lambs. Thus, this year no ewe lambs were put on test.

Yield grade target was a YG 2, and lambs on test, Huston said, averaged 1.7. All were graded YG 1 or 2.

"Verbally we were told that our lambs weren't quite fat enough."

The ongoing project, Lupton told the group, is expected to last three more years. Other variables to be evaluated in the coming years will be a comparison of the physical environment — animals on the raised floor versus the feedlot and the range, and ultimately the cost of production in a raised floor situation.

This year Angelo State University graduate student James Jennings is evaluating two types of genetics, Rambouillet and Rambouillet-Merino crosses, 150 animals in each breed type, in the three different environments. Because of the problems with the break joint in the ewe lambs, only wether lambs were used.

The ration was changed a bit this year, Jennings told field day participants. They were able to find a feed manufacturer to make an oat hay-based pellet, which researchers expect to help greatly reduce contamination due to vegetable matter. The pellet, he noted, has 10 percent more wheat, which is expected to give a bit more boost and help in average daily gain.

This year researchers are also evaluating the use of coats on the animals to help produce a higher quality clean fleece. And in addition to the standard fiber and feeding measurements, other research counterparts will be doing some in-depth carcass work involving composition and nutrition.

Jennings reported preliminary data from the first 64 days of the trial study.

Merino cross lambs came from Nevada and the Rambouillet lambs came from different parts of Texas. To help negate previous differences in environmental conditions, all lambs were fed the same diet in a feedlot environment for a period of three weeks prior to the start of the feeding trial.

Lambs were blocked by weight, and the feeding trial began June 29th after dye banding all fleeces. Fleeces were dye banded, Jennings explained, so he had a reference point to take measurements.

Jennings reported the most recent data collected, that at the 63-day period. Average weight was significantly different for the various animals. Feedlot animals averaged 102.7 pounds, 93.4 pounds for those on the raised floor and 83.6 pounds for those on native pasture.

Average daily gain for feedlot lambs was a little less than half a pound a day, just under the target, .15 on pasture and .31 pounds per head per day for those on the raised floor, right where the researchers wanted them.

"The Rambouillet lambs are performing a little better than the Merino-Rambouillet crosses so far," Jennings told listeners.

At 63 days, the Rambouillets weighed on average 96.5 pounds and the crosses 90.2 pounds. Rambouillets did slightly better in average daily gain as well.

In comparing coated versus uncoated lambs, Jennings reported a 72.8 pound initial average weight for uncoated lambs and 74 for those with coats. At 63 days, the coated lambs weighed 95.3 pounds and the uncoated 92.6 pounds. Average daily gain was significantly different, .35 for the coated lambs and .29 for the uncoated lambs.

Huston and Lupton wrapped up by identifying what they had learned thus far.

"We know we have to pay more attention to the uniformity of lambs going on test," Huston told listeners. "Our experience the first year was that the animals came out less variable than what they started out, but they were highly variable in the beginning.

"We've identified a feed type that will accomplish what we want — a slow, uniform rate of gain — so that way we can produce a lean carcass and a uniform saleable fiber that we think will bring a premium."

The nutritionist said all the anticipated advantages of the raised floor have materialized.

"These animals are extremely healthy, they do very well, they’re very comfortable, the manure is not a problem. We pull it out with a front-end loader and the odor problem is not there."

The researchers, however, have not shown that the raised floor system is economically superior to the traditional feedlot.

"That data is not in hand," Lupton said. "It may never be in hand, as far as producing pounds of wool and pounds of lamb, but based on what we learned so far we remain very optimistic that these raised floors have the potential for producing superior lean carcasses and uniform, clean wool."

The fiber specialist added that the industry still faces a major challenge in developing price discovery for these superior products.

"We're optimistic, however. Once Ranchers’ Lamb gets their fabrication plant in, we believe we will be rewarded for these heavier, leaner lambs.

"As for clean, uniform wool, we know some cases where it is already bringing quite a lot more than average price. So through innovative and creative marketing channels we feel we will be paid for it," Lupton concluded.

Cost of production of such an enterprise will be the focus in the coming year.