The sheep industry is in a transitional phase because of the loss of the wool commodity program, and now is turning to lamb as its main commodity. In addition, sheep producers, novel and experienced, are looking for easy care, low maintenance breeds of sheep. Hair sheep appear to fit the mold because they never need shearing, possess some degree of parasite and disease resistance, and are adaptable to different environments. On the down side, hair sheep tend to produce smaller, slower growing lambs than traditional wool breeds.

Researchers at the Center are examining productivity of a relatively new breed of hair sheep in this country, the Dorper. The Dorper breed may add some size and carcass acceptability when used in a crossbreeding program with other hair sheep breeds. Major hair breeds in our country include Katahdin, St. Croix, and the Barbados Blackbelly. The Katahdin was developed in Maine in the 1950s from hair sheep from the Carribean crossed with a variety of wool sheep, including Suffolk and Wiltshire Horn. Weight of mature ewes range from 120 to 160 pounds. The St. Croix breed was imported to the mainland U.S. from the Virgin Islands in 1960 (mature ewes: 125 to 150 pounds) and Barbados Blackbelly was imported from the Carribean in 1904 and range in weight from 70 to 130 pounds. Range in weight of Dorper ewes is between 170 and 200 pounds. These weight ranges are from American Sheep Industry Association, Englewood, CO. Weight ranges in the southeast may be lower perhaps because of the heat stress and lower feed quality compared with cooler climates in the U.S.

A study was completed last fall that evaluated growth and carcass characteristics of St. Croix and Dorper x St. Croix wethers for 120 days after lambs were weaned. Lambs were raised intensively in a feedlot type system. Dorper x St. Croix lambs had the highest average daily gain, heaviest carcasses, and largest longissimus muscle area (which means larger lamb chops). Using the Dorper as a terminal sire in a St. Croix flock appears to be an acceptable means to produce larger, faster growing lambs.

At this time, more work needs to be done before management recommendations can be made for hair sheep. One potential strategy for producing market lambs from hair sheep is to breed a larger wool-type ram to hair-type ewes for terminal lambs. A hair breed sire would be needed to generate replacement ewes. This way, only the ram would require shearing. In addition, there are ethnic markets that desire smaller frame lambs, which provides an outlet for the hair breed wether lambs.

Another aspect of hair sheep management being studied is parasite control. Breeds are being evaluated for their tolerance to internal parasites. The infection from parasites can markedly impact the performance of an animal because of the detrimental effects on health (anemia, edema, diarrhea, etc.). Parasites have become resistant to dewormers that are currently available. New anthelmintics are far-off in the future. Sheep that can carry intestinal parasites without affecting performance would be an asset to any operation. In this study, fecal egg counts will be determined for individuals from each breed flock to assess internal parasite resistance on mature ewes and weaned lambs. Preliminary data suggest that the Dorper possesses at least some degree of parasite resistance as compared with St. Croix and Katahdin breeds.

Taste Panel Finds Lamb as Acceptable as Beef

A glance in the meat section of any grocery store in the U.S. will tell you that Americans eat more beef than lamb. Does this mean that Americans do not like the taste of lamb?

At the mini-field day held at the Center last October, participants compared the taste and tenderness of a lamb product to that of beef filet mignon in a non-scientific taste test. The lamb was derived from Dorper x St. Croix or St. Croix wether lambs that were grown at the Center as part of a growth and carcass evaluation study in summer and fall of 2000. The lamb mignon had an appearance of beef filet mignon. The lamb product was made by processing the entire carcass and then wrapped with bacon. The lamb mignon was developed by Dr. Jason Apple at the Department of Animal Science, University of Arkansas in Fayetteville. The meat was cooked on a gas grill and served as Sample A or B. If lamb is not cooked properly, where the fat drains away from the meat, an off-flavor and odor may be present.

Members of the survey rated the meat products for appearance, initial tenderness (first 5 bites), initial juiciness (first 5 bites), sustained juiciness and tenderness (just before swallowing), overall flavor, overall desirability, and whether they would purchase the product (Table 1). Consumers rated both products similarly in all categories except tenderness. The lamb meat was more tender than the beef. Considering that many of the taste panel members were cattlemen this suggests that lamb is just as acceptable as beef!

*Statistically greater preference for lamb tenderness.