David A. Phelps

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Results are summarized of necropsy findings from 798 calves lost from birth to weaning over a 15-yr period. Autopsies determined cause of death and ascertained anatomical normalcy of the skeletal, musculature and organ systems and functinal status of the lungs. Of the 798 calves, 77.7% were anatomically normal and 22.3% were abnormal (P < 0.01) and 75.0% of(More)
This experiment had two objectives. The first was to test a hypothesis that the presence of mature cows can influence the growth rate and physiological maturation rate of growing heifers. The second objective was to define a phenomenon termed nonpuberal estrus (NPE). Nonpuberal estrus in a prepuberal heifer is a behavioral estrus that is not followed by(More)
A normalized enzyme-linked immunosorbent assay for the determination of immunoglobulin G antibodies to cytomegalovirus is described. The rapid assay involves three 30-min incubations and permits the quantitation of antibody levels with a single-specimen dilution in conjunction with a reference antibody preparation. The results obtained with the normalized(More)
One hundred twenty-five patients with 194 supernumerary toes were analyzed. Postaxial polydactyly accounted for 79%. Duplication at the proximal phalanx with either a block metatarsal or a wide metatarsal head was the most common anatomical pattern. Sixty-one patients with 97 duplications evaluated at an average follow-up of 15.1 years postoperatively had(More)
Two trials were conducted to examine the effects of estrus synchronization scheme, gonadotropin injection protocol and presence of a large ovarian follicle on response to superstimulation of follicular development and the ensuing superovulation. Estrus was synchronized with either a progestin compound (MGA) or by the use of a luteolytic agent (PGF).(More)
Beef cows were superovulated with follicle stimulating hormone (FSH) to compare two nonsurgical methods of embryo recovery from the uterus. In the first method each uterine horn was independently flushed with physiological saline solution (PSS) through a Foley catheter passed through the cervix and into the uterine horn. In the second method both uterine(More)
This study was designed to examine how the cognitive functions of attention and automaticity, as identified in the Stroop Effect phenomenon, are impacted by frustration. It was hypothesized that being in a frustrated state would inhibit attentional override of reading automaticity, thereby exaggerating the Stroop Effect. To test this, N = 24 participants’(More)
Oocytes and follicular components obtained from ovaries recovered from mature Hereford cows at slaughter were used to determine follicular influence on oocyte maturation. Some oocytes were fixed immediately to determine the stage of maturation. The remaining oocytes were cultured for 32 to 34 hr in various environments to determine the influences of the(More)
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