Evaluating the potential for lambs to bond to heifers

TitleEvaluating the potential for lambs to bond to heifers
Publication TypeConference Paper
Year of Publication1993
AuthorsAnderson D.M., Walker J., Havstad K, Murray L.W.
Conference NameAnnual Meeting, Society for Range Management
Date Published1993
AbstractSince 1986, two bonded wether sheep on the Jornada Experimental Range (JER) have consistently stayed closer to cattle compared to ewe lambs of similar age and breeding. A joint USDA-ARS ewe-wether sibling study was begun in 1992 to investigate how gender may influence bonding cohesiveness. Purebred Polypay and 1/2 Rambouillet, 1/2 Polypay crossbred sheep were evaluated on the JER, Las Cruces, New Mexico, while purebred Rambouill and 1/4 Finn, 3/4 Columbia or 3/4 Targee crossbred sheep were handled under similar management on the U.S. Sheep Experiment Station, Dubois, Idaho. Lambs were weaned at approximately 60 days of age. Immediately, seven lambs of the same gender and three yearling beef heifers were randomly allocated to one of six pens (three experimental units/gender), each approximately 675 m2 in size, for 60 days using previously described protocol. Pens had a lamb creep area while baled alfalfa in a common bunk was fed ad libitum along with water and mineral blocks. In a 4-h field trial 60 d post pen-confinement, the tendency for lambs to follow the heifers was evaluated by measuring separation of the two animal species and calculating means +/- standard errors to describe cohesiveness. At Las Cruces, wether lambs followed heifers closer (1.45 +/- 0.82 m) than ewe lambs (6.58 +/- 0.82 m; P = 0.001). Idaho lambs did not follow cattle as close as did JER lambs nor did they demonstrate a consistent cohesiveness to stay with cattle. In contrast to JER lambs, Idaho ewe lambs formed a closer association (18.94 +/- 2.87 m) to heifers compared to wethers (29.20 +/- 3.31 m). Lamb cohesiveness to heifers did not appear similar between siblings at either location.