Record Details
Genetic and physiological factors associated with gonadotropic and thyrotropic hormone content of sheep pituitaries
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Genetic and physiological factors associated with gonadotropic and thyrotropic hormone content of sheep pituitaries |
| Names |
Plotka, Edward Dennis
(creator) Bogart, Ralph (advisor) |
| Date Issued | 1963-05-10 (iso8601) |
| Note | Graduation date: 1963 |
| Abstract | Data were taken from 47 animals consisting of five breeds: Border Cheviot, Columbia, Dorset Horn, Suffolk, and Willamette. Both sexes were represented in each breed, although in unequal numbers. The pituitaries were assayed for gonadotropic and thyrotropic hormone content by injecting a suspension of the macerated gland in saline into one-day old chicks. Five levels of the suspension were injected subcutaneously into the breast area of the birds once a day for four days. The amount of hormone present in the pituitary was measured by the increased weight of the testes and thyroids over those of the controls in the assay animals. Analysis of the data showed that there were no differences in the hormone content per unit of pituitary weight of the pituitaries between the breeds or sexes of the animals. Significant differences (P < 0.1) due to breed were found in the live weight of the animals, and in the pituitary weights of the animals. A correlation coefficient of 0.5769 was found between pituitary weight and live weight. From these data, it was concluded that the differences in the growth and reproduction of different breeds of sheep are associated with differences in the total amount of gonadotropic and thyrotropic hormones present in the pituitary gland rather than the concentration of hormone per unit of gland. |
| Genre | Thesis/Dissertation |
| Topic | Sheep breeds |
| Identifier | http://hdl.handle.net/1957/48759 |
