Twenty-eight indigenous ewe lambs (6 months of age and 14.4 kg body weight (BW)) were used to evaluate the effect of feeding Sporobolus grass hay (SGH) as the only source of forage on growth, and feed and water intakes. The ewe lambs were randomly and equally allocated to two treatment groups (14 lambs/group).
View Article and Find Full Text PDFGenetic parameters for birth weight were estimated for two sets of purebred and crossbred lambs in United Arab Emirates, using animal model methods. Data were analyzed by restricted maximum likelihood (REML). Five different animal models were fitted.
View Article and Find Full Text PDFSelection 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.
View Article and Find Full Text PDFGenetic parameters for female reproduction, lamb growth, and lamb scrotal circumference in a composite population of 50% Dorset, 25% Rambouillet and 25% Finnsheep breeding selected for ability to lamb in fall were estimated by REML using various animal models. Traits considered were spring fertility, litter size, weight at weaning (WWT), 90 d (WT90), and 120 d (WT120), and scrotal circumference at weaning (WSC), 90 d (SC90), and 120 d (SC120). Fertility was defined as 1 or 0 for ewes that lambed or failed to lamb, respectively, in fall and averaged .
View Article and Find Full Text PDFCharacteristics of preimplantation embryonic development to Day 3.5 of gestation were evaluated in lines of mice after 21 generations of selection for litter size or components of litter size. Selection criteria were direct selection for number born (LS), selection on an index of ovulation rate and the proportion of ova shed that resulted in fully formed pups (IX), selection for number born in unilaterally ovariectomized females as an indication of uterine capacity (UT), and an unselected control (LC).
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