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Filtering by: Subject Sheep -- Breeding Remove constraint Subject: Sheep -- Breeding Non-Academic Affiliation Oregon State University. Graduate School Remove constraint Non-Academic Affiliation: Oregon State University. Graduate School

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  • Comparison of Dorper and Polypay as maternalsire breeds for reduced input lamb production

    Creator:
    Haas, Joel D.
    Abstract:
    During years 2005, 2006, and 2007 ewes of predominantly Polypay breeding were bred to either Dorper or Polypay rams for spring lambing. Ewes were assigned to single-sire mating groups based on age and genotype. Internally generated replacements were added to the flock for the 2007 lambing season and bred to...
    Resource Type:
    Masters Thesis
    Full Text:
    : ____________________________________ Howard H. Meyer During years 2005, 2006, and 2007 ewes of predominantly Polypay breeding were

  • Crossbred lamb production from Columbia and Suffolk ewes

    Creator:
    Levine, Joel Martin
    Resource Type:
    Masters Thesis
    Full Text:
    . Ewe Production and Lamb Traits II. Simulation of the Sheep Flock: Net Income Per Ewe AN ABSTRACT OF

  • Effects of sire breed on growth, feed efficiency, and carcass traits of cross-bred lambs slaughtered at three weights

    Creator:
    Collins, Debora Ann
    Abstract:
    This study examined the effects of sire breed and weight on the performance of 117 crossbred wether lambs born at the Oregon State University Agricultural Experiment Station, Corvallis. Lambs were produced by mating Clun Forest,Polypay, Dorset, Border Leicester, and Suffolk sires to Columbia-type ewes. After weaning at approximately 90 days...
    Resource Type:
    Masters Thesis
    Full Text:
    review of sheep crossbreeding studies by Nitter (1978) indicated that crossbreeding systems generally

  • Genetic and environmental variation in production components of purebred and crossbred ewes

    Creator:
    Nawaz, Mohammad, 1957-
    Abstract:
    Coopworth sheep, a newly available genotype, were compared with other genotypes in two trials to assess cumulative lamb and wool production and contributing components related to survival, reproduction and growth, and for the effects of ewe body weight on reproductive traits. In a third trial, various genotypes generated in the...
    Resource Type:
    Dissertation
    Full Text:
    approved: Howard IV Meyer Coopworth sheep, a newly available genotype, were compared with other

  • Genetic polymorphism of sheep hemoglobin

    Creator:
    Templeton, Joe Wayne, 1941-
    Abstract:
    Five breeds of sheep (Columbia, Targhee, Rambouillet, Lincoln, and Suffolk) were found to possess two hemoglobin types (Hb. A and Hb. B) when their hemoglobins were examined by disc gel electrophoresis. The hemoglobin alleles proved to be co-dominant. Three of the breeds (Columbia, Targhee, and Rambouillet) were maintained at altitudes...
    Resource Type:
    Dissertation
    Full Text:
    Columbia breeds were developed at the U. S. Sheep Breeding Station from crosses of Lincoln X Rambouillet

  • Genetics of sheep transferrins as determined by disc electrophoresis

    Creator:
    Nix, Carroll Eugene
    Abstract:
    A total of 902 plasma samples from the Rambouillet, Targhee, Columbia, Lincoln, and Suffolk breeds of sheep were analyzed for transferrin type by disc electrophoresis. Six transferrin types, Tf[superscript A], Tf[superscript B], Tf[superscript C], Tf[superscript p], Tf[superscript E], and Tf[superscript P], were found in the Rambouillet, Targhee, and Columbia breeds...
    Resource Type:
    Dissertation
    Full Text:
    breeding sys- tem used at the U. S. Sheep Experiment Station as this involves a major part of the study

  • Ova tranfers in sheep and rabbits : studies on material influences and irradiation damage

    Creator:
    Hunt, William Lynn
    Abstract:
    The first study utilized ova transfer in sheep and involved hormonal treatments for synchronization of estrus and superovulation in an investigation of crossbred maternal influences on inbred and linecross lambs. Synchronization of estrus in ewes was achieved effectively with either oral progestogen, 6 α-methyl-17α-hydroxy-progesterone acetate (60 mg./ewe/day), or intramuscular injections...
    Resource Type:
    Dissertation
    Full Text:
    has not been accepted for any large scale breeding prograrn, although an atternpt with sheep in

  • Regulation of ovine pituitary function with estrogen alone and in combination with progresterone

    Creator:
    Osland, Robert Birger
    Abstract:
    Five experiments were conducted to study the activity of the pituitary gland in sheep as influenced by estrogen administered alone or in combination with progesterone. Particular emphasis was given to the study of gonadotropic activity. Mature wethers (experiments I, III, IV and V) or ewes (experiment II) were utilized as...
    Resource Type:
    Masters Thesis
    Full Text:
    study the activity of the pituitary gland in sheep as influenced by estrogen administered alone or in

  • Some genetic and environmental factors affecting weaning weights of lambs

    Creator:
    Dahmen, J. J. (Jerome John), 1919-
    Abstract:
    Eight purebred rams (four Suffolk and four Panama) previously selected as high and low on the basis of post-weaning performance feed test of 84 days were used each of three years. Each of the rams was mated to approximately 25 grade Panama ewes each year. One ram and 25 ewes...
    Resource Type:
    Dissertation
    Full Text:
    produce these in quantity and quality have economic value in breeding for sheep im- provement. Weaning

  • Some hormonal factors associated with the regulation of ewe reproductive patterns

    Creator:
    Reeves, Jerry John
    Abstract:
    Twenty-eight Columbia ewes were made available for study during their breeding and anestrous seasons. After the regularity of the estrous cycles had been established, eight of the ewes were sacrificed in pairs at four different stages of the estrous cycle. Eight additional ewes were sacrificed during anestrus. Pituitary glands, ovaries,...
    Resource Type:
    Masters Thesis
    Full Text:
    approximately the midpoint of the breeding season for the ewe. The domestic sheep is a seasonally