Primiparous ewes born as singletons to Rambouillet x Columbia crossbred ewes fed either 100% of NRC recommendations (control, Con; n = 7) or 50% of NRC (nutrient restricted, NR; n = 7) from d 28 through 78 postmating were utilized for this study. At 1 yr of age, a subset of ewes born to Con (n = 4) and NR (n = 4) mothers received jugular catheters and were subjected to a corticotrophin-releasin...

Lifetime production of first-generation 1/4 and 1/2 Finnsheep crossbred ewes from Rambouillet (R), Targhee (T) and Columbia (C) dams was compared with that from randomly selected purebred R, T and C ewes. All 1,190 ewes, representing nine breed groups, were managed under range conditions and mated annually to Suffolk rams. Lifetime production was evaluated as the total lamb and total wool produ...

The aim of this study was to evaluate the reduction in water supply (ad libitum intake - 100%, or 80%, 60% and 40% ad intake) on proximate composition, physicochemical properties, mineral composition fatty acid profile ewe meat. Thirty-two crossbred Santa Inês (n = 8 per treatment) were distributed a randomized block design, receiving diet consisting elephant grass concentrate (70:30). experime...

Selection for fertility in a fall lambing system was applied for 5 yr (1.45 generations) in a crossbred sheep population. Three flocks were involved: a fall-lambing selected (S) flock of 125 ewes and 10 rams, a fall-lambing environmental control (EC) flock of 55 ewes and five rams, and a spring-lambing genetic control flock of 45 ewes and five rams used to produce replacements for EC. Estimated...

In two experiments, 64 crossbred ewes that had lambed in September or January and had their lambs removed within 24 h after birth were assigned to four groups and given the following treatments: group 1 (16 ewes)-1 ml saline, im or iv on d 10 postpartum; group 2 (24 ewes)-150 microgram/gonadotropin releasing hormone (GnRH) in 1 ml saline, im or iv on d 10 postpartum; group 3 (16 ewes)-150 micro...

The IgG1 concentrations in two-day-old lambs were significantly correlated with litter size, date of lambing, length of gestation and age of the dam. When these and other effects were allowed for significant breed differences were found, the concentrations being relatively high in Finnish Landrace, Welsh Mountain and Soay lambs, and relatively low in Border Leicester, Oxford Down and Southdown ...

An experiment was designed to evaluate the effects of five sire breeds (Dorset, Finnsheep, Romanov, Texel, and Montadale), two dam breeds (Composite III [CIII] and northwestern whiteface [WF]), and three shearing seasons (December, February, and April, corresponding to August, October, and December breeding seasons) and their interactions on wool and other characteristics of F1 ewes. Fleeces we...

Data from 644 exposures and 552 lambings were used to analyze reproductive traits of 1/2-Finnish Landrace, 1/2-Dorset ewes (1/2 Finn); 1/4-Finnish Landrace, 3/4-Dorset ewes, (1/4 Finn) and Dorset ewes. Ewes were exposed to Hampshire or Suffolk rams for spring lambing from 1973 to 1978. The analytical model included fixed effects of ewe birth year (EBY), ewe breed (BR), lambing year within EBY a...

We determined the polymorphism C242T of the aromatase gene (Cyp19) and its allelic frequency, as well as the effect of the variants on productive and reproductive traits in 71 purebred Santa Inês sheep, 13 purebred Brazilian Somali sheep, nine purebred Poll Dorset sheep, and 18 crossbred 1/2 Dorper sheep. The animals were genotyped using the PCR-RFLP technique. The influence of the animal's gen...

The effects of progestogen-gonadotropin treatment on estrous response, ovulation rate and lambing response of crossbred ewes were examined at two times during the anestrous season (May-June and July-August). Each ewe group was treated with progestogen pessaries for 16 days and injected with 750 IU pregnant mare serum gonadotropin (PMSG) on days 17 and 32 to induce two consecutive estrous period...