Scrapie is one of several transmissible spongiform encephalopathies of livestock. Disease susceptibility is linked to polymorphisms in the normal prion protein gene that encodes the mammalian prion precursor. Codon 171 of this gene is a major determinant of scrapie susceptibility. Selection for arginine (R) at codon 171 is encouraged by the USDA to decrease the incidence of scrapie. Objectives ...

Despite a shortage of animal feed in Iran, cereal stubble is often underutilized due to agro-economic reasons. On the other hand, lambs fed with a conventional fattening ration deposit a considerable amount of fat; therefore, this experiment was conducted aimed at better utilization of cereal stubble and reducing the fat content of lamb carcasses. Fat-tailed Mehraban and Ghezel ram lambs were p...

The objectives of this experiment were to assess effects of animal age and castration on activities of calpain I, calpain II, and calpastatin in sheep skeletal muscle. Ten newborn male lambs (2.9 kg), six weaned wethers (23.2 kg), six weaned rams (22.2 kg), six market wethers (55.4 kg), and six market rams (60.2 kg) were slaughtered and samples of biceps femoris were taken for assay of calpain ...

A diallel cross involving three Moroccan breeds of sheep (Sardi, Beni Guil, and D'man) was analyzed by least squares procedures. A total of 456 ewes were mated to 22 rams and this resulted in 528 lambs born from 412 ewes. D'man ewes had by far the highest general performance as measured by total weight of lamb weaned, even though the average live weight per lamb was the lowest for the three bre...

To determine the effect of breed on copper status of crossbred (F1) lambs, a study was conducted using 187 crossbred wether lambs. Wether lambs were progeny of five ram breeds (Dorset, Finnsheep, Montadale, Romanov, and Texel) and two ewe breeds (Rambouillet and a composite breed [1/2 Columbia, 1/4 Suffolk, 1/4 Hampshire]). Diets were adjusted to decrease crude protein twice during the experime...

The purpose of the study was to determine the effect of trenbolone acetate (TBA) on performance, plasma lipid metabolites, and carcass characteristics of growing ram and ewe lambs in two separate experiments. Treatments consisted of 1) a control, no implants, and 2) a TBA implant (60 mg of Finaplix; Hoechst-Roussel Agri-Vet). Twelve Rambouillet cross ram lambs (average 19.9 kg BW; Exp. 1) and 1...

The effect of FSH on the development of the testis in the ram lamb was examined in two experiments where lambs were passively immunized against ovine beta-FSH from birth until 100 or 160 d. In both experiments, immunization resulted in a slower testicular growth relative to that of controls. This effect became apparent at around the start of the period of rapid testicular growth (60-70 d of age...

AIM Present experiment was conducted to investigate the effect of selenium (Se) supplementation on performance, carcass characteristics, meat composition, shelflife of meat and biochemical profile in Nellore ram lambs. MATERIALS AND METHODS 24 male Nellore ram lambs (15.75±0.47 kg) were randomly divided into four dietary groups with six lambs in each and reared under uniform management condit...

Our objective was to estimate genetic parameters for feed intake, feeding behavior, and ADG in composite ram lambs ((1/2) Columbia, (1/4) Hampshire, (1/4) Suffolk). Data were collected from 1986 to 1997 on 1,239 ram lambs from approximately 11 to 17 wk of age at the U.S. Meat Animal Research Center near Clay Center, NE. Feeding equipment consisted of an elevated pen with an entrance chute that ...