An experiment was conducted with 51 control and 51 experimental confinement-
managed purebred Yorkshire sows of various parities to (1) determine
whether confinement-managed sows during lactation would exhibit estrus,
mate, and conceive as a consequence of a daily regimen of a short period of
separation from their litters, mixing sows...
The role of hypothalamic biogenic amines (norepinephrine,
dopamine and serotonin) in regulating the release of luteinizing
hormone (LH) in the ewe was investigated. Eleven experiments
utilizing mature crossbred or Hampshire ewes were conducted to
determine the ability of exogenous 17β-estradiol and various pharmacological
agents to alter the levels of hypothalamic...
A study has been made of the vertical distributions and
migrations of a large number of zooplankton species at Weather
Station "P" in the Subarctic Pacific. Simultaneously towed horizontal
opening-closing nets were used for the study. The distributions
and migrations of 104 taxa have been subjectively grouped
into seven basic...
Heart rates and amplitudes were measured for both intact
animals (in situ) and isolated hearts (in vitro) of the Dungeness crab,
Cancer magister, exposed to low levels in oxygen. Recordings were
also made of gill ventilation rate by measuring the frequency of
scaphognathite (gill bailer) beats.
Both the in vitro...
This report summarizes the results of a field study of a population
of the Pacific mountain beaver, Aplodontia rufa pacifica, from
August 1965 through August 1967. The study site consisted of a 13. 5-
acre grid on a logged over area in the Coast Range Mountains of
Benton County, Oregon....
The Dover sole has been the most important flatfish in Oregon's trawl fishery since its beginning in 1938. At that time the fish was called slime sole, because the animal produces great quantities of the stuff. The term Dover sole apparently comes from the north Atlantic where a similar creature...
Grazing on the mountainous forested ranges of the Camp Creek
Unit, Malhuer National Forest, was typified by irregular distribution
of free-ranging cattle. A combination of management and physical,
topographic constraints caused cattle to concentrate on the riparian
zone early in the grazing season in 1977 and 1978. A large percentage...
Intensive observations were made of play behavior in the
young hamster (Mesocricetus auratus) from 14 to 54 days of age.
Behavior was recorded using movie film and a multi-channel event
recorder.
Play was first seen at 14 days of age. The amount of play
increased rapidly thereafter, remaining relatively high...