The investigations were based on a complete diallel cross
among three inbred lines of Suffolk sheep. Line of sire effects were
assumed to be an estimate of general combining ability effects while
sire x dam interaction was assumed to be an estimate of specific
combining ability. The line of dam...
An experiment was conducted to examine the responses to
selection for high and low rate of gain in the mouse under a system
whereby inbreeding was maximized. Rate of gain was measured by an
index designed to include gains in both the pre- and postweaning
periods with the gains in...
Mice were used to compare the index and elite selection
methods for simultaneous selection of four traits. Selection was
for litter size, birth weight, weaning weight and post-weaning
gain. Progress was evaluated by examining total phenotypic merit.
The standard deviations from the cycle mean for the four traits
were summed...
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...
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...
The relationship between x-ray induced chromosome aberrations
and x-ray induced embryonic abnormalities was studied. Golden
hamsters were irradiated during four stages of gestation: the blastocyst
stage, 4.5 days post-copulation; the primitive streak stage, 6.5
days post-copulation; the organogenesis stage, 9.5 days post-copulation;
and the period of fetal growth, 11.5 days...
Research has yielded valuable information about the inheritance of body weight in many mammals. The results with one species may not be directly applicable to another species, but since the results do not contradict genetic theory, one must assume that the same general rules apply to all species.
When the...
There were two studies involved in the thesis research. In the
first study, variation in the amount of adenohypophysis gonadotropins
among 22 individual beef bulls were investigated. These bulls
represented four inbred lines, and six linecrosses. The bulls were
raised in the Oregon State University purebred herd.
The bulls were...
Data were presented on epididymal spermatozoa from 29 inbred
and linecross bulls raised at Oregon State University in connection
with the Western Regional Beef Cattle Breeding Project, W-1. The
inbred bulls came from four inbred lines. Three of these inbred
lines were Herfords and the other line was Angus. The...