Comparative gonadotropic potency of unfractionated extracts of poultry pituitaries

The gonadotropic potency of avian hypophyses was determined by injecting a suspension of acetone-dried glands into immature female rats. The degree of response was measured by the change in the histology of the epithelium of the vagina;On the basis of available evidence, the approximate threshold amount of acetone-dried pituitary material (whole gland) required to produce stage 3 (the vaginal unit) in the vaginal epithelium of this particular strain of rats was as follows: (a) Capons---7.5 mg. (b) Springs (2.5 to 3.5 lbs.)---14.2 mg. (c) Roasters (3.5 to 6.0 lbs.)---14.6 mg. (d) Turkeys---19.4 mg. (e) Pullets (approaching sexual maturity)---26.0 to 27.5 mg. (f) Fowl (medium to poor fecundity)---34.3 mg. (g) Fowl (good production)---40.0 mg. One positive response was obtained by injecting 25.0 mg. of Pekin duck hypophyses;Sufficient pituitary powder was not available to determine the rat vaginal unit for old cocks, geese, guineas and pheasants, but the indications were that the hypophyses of these birds did not contain appreciable gonad-stimulating properties;Age and state of reproductive activity have a pronounced effect on the gonadotropic potency of avian pituitaries. In general the glands of young birds (springs) are more potent than older birds and the glands of non-laying females are more potent than the hypophyses of laying hens;The follicle-stimulating and luteinzing potency of the hypophyses obtained from male birds was greater than obtained from females providing age was considered

PERFORMANCE EVALUATION OF SEDIMENT BASIN DESIGNS FOR HIGHWAY CONSTRUCTION SITES IN TENNESSEE

Performance of three sediment basin designs were tested; they were: 1) the TDEC standard design with a forebay, 2) the TDOT design with an inlet check dam, and 3) the TDOT standard design that does not include an inlet check dam. An 1/17 of an acre scaled physical model sediment basin, was constructed next to an elevated outdoor open flume used to mix known water volumes and sediment mass routed by gravity-flow into the basin. The measurement for performance was simply the percent sediment mass retained in the basin from the total input per experimental run (percent sediment removal). Three experimental replicates per design were completed. Sediment was analyzed by concentrations, loads, and particle size distributions (PSDs). All designs were above the 80% removal regulatory requirement for Tennessee: with TDOT, TDEC, and TDOT with check dam design achieving a total percent sediment removal of 95.4 %, 98.2 %, and 97.9 %, respectively. PSD data from the experiments provided key information for developing a sediment-basin design model to account for differential particle size settling. In addition, these experimental results were compared with sediment basin performance data collected at active highway construction sites, as well as from other published experimental studies

Wyandot Indians, 1843-1876

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Development and Impact of the Parking Meter Before World War II

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Resilience in Virginia: Outlook 2021

VCPC\u27s October webinar included an update on Virginia’s participation in the Regional Greenhouse Gas Initiative and the implementation of Executive Order 24; remarks from the Speaker of the House of Delegates, Eileen Filler -Corn, and a legislative panel discussed resilience issues for the upcoming 2021 Virginia General Assembly session. VCPC was honored to host Governor Ralph Northam for Closing Remarks