A group of crossbred Dorset or Finnish Landrace ewes maintained under a synthetic light regimen (Light Treatment, 4 mo long days - 16 h light, 4 mo short days - 8 h light) and exposed to rams every 8 mo (January 1, September 1, May 1) was compared for lamb production over a period of 4.5 yr with two other comparable groups under natural daylight conditions, one exposed to rams once a year in th...

Reproductive performance and body weights of four and five-year old crossbred ewes representing five combinations of Finnsheep (F), Dorset (D) and Rambouillet (R) breeding were evaluated when lambing in the summer Oune-July, 1976). The five breed combinations represented were 1f2D, 1f2R; %D, %R; %F, 1f2D, %R; %F, %D, 1f2Rand %F, 3f4R. Breeding effectiveness of purebred and crossbred rams of Ham...

A total of 399 crossbred ewes born in 2 yr were maintained either on irrigated or dryland hill pastures. The ewes were sired by North Country Cheviot, Dorset, Finnsheep or Romney rams mated to Suffolk or Columbia-type ewes. The crossbred ewes were mated to Hampshire rams throughout the study and had the opportunity for either 4 or 5 yr of production. Annual feed cost was calculated based upon e...

Reproductive performance of four, five and six-year old crossbred ewes representing six combinations ofFinnsheep (F), Dorset (D), Rambouillet (R), and White Face Western (WFW) breeding were evaluated when lambing in the winter (February-March, 1977) and in the fall (October-November, 1977). The six breed combinations represented were 3fsF, 5fsWFW; %F, 1f2D, %R; %F, %D, 1f2R; %F, %R; 1f2D, 1f2R;...

reproductive performance was evaluated in non-lactating crossbred ewes to which were administered the exogenous gnrh and pmsg. the ewes were randomly allocated in three treatment groups (n=40).after accurate detection of estrus and 2 hours prior to mating, 2.5 ml of distilled water and 2.5 ml of gnrh were injected intramuscular to each ewe of the first (control) and second group, respectively. ...

The efficacy of two doses of progesterone (P4), i.e. 350 and 300mg was evaluated in acycling crossbred ewes (50) during the autumn breeding season. Ewes were treated with intravaginal progesterone sponges with either 350mg or 300mg for 12 days. At standing estrus, ewes were hand mated (three cycles). Progesterone (350mg) gave a better (P<0.05) estrus response (75%), compared to 300mg dose (42%)...

A study was undertaken to compare the longevity and lifetime lamb output of purebred Scottish Blackface (BF) ewes with a range of crossbred genotypes from Scottish BF dams. For up to five successive breeding seasons, 1143 Scottish BF, Swaledale × BF (SW × BF), North Country Cheviot × BF (CH × BF), Lleyn × BF (LL × BF) and Texel × BF (T × BF) ewes were mated to a range of sire breeds on six hill...

An experiment was conducted to determine whether controlled internal drug release devices-type G (CIDR-G) could be used in conjunction with the ram effect to advance the breeding season and lambing and thereafter could be reapplied to stimulate breeding of ewes to produce a second lambing in late summer. Finn crossbred and Columbia ewes were treated with CIDR-G from July 6 to 18. Rams, which ha...

Adult East Freisan crossbred (n = 220) and Chios ewes (n = 105) were divided into four groups and inseminated with chilled semen, which had been stored for 7, 13, 20 or 26 h at 5°C. Unilateral intrauterine insemination (50 x 10 6 spermatozoa in 0.25 ml) was performed with the aid of a laparoscope. Inseminations were carried out 48 – 52 h after pessary removal (30 mg FGA) without detecting estru...

The purpose of this research was to evaluate differences in parasite resistance of Barbados blackbelly ewes and Suffolk crossbred ewes. 40 ewes were used for this study; 20 were Suffolk crossbreds and 20 were Barbados blackbelly. Fecal egg counts (FEC) verified that there were zero internal parasites in the sheep at the start of the experiment. The sheep were placed on a previously grazed pastu...