Genetics Commons^™

More Lambs By Mating Weaners, R J. Suiter

Journal of the Department of Agriculture, Western Australia, Series 4

Farmers can increase sheep numbers by mating ewe weaners. Trials have shoen that this does not affect the later performance of these ewes.

Buoyancy Changes As Related To Respiratory Behavior In An Amphibious Snail, Pomacea Urceus (Müller), From Venezuela, Kathleen A. Burky, Albert J. Burky

Biology Faculty Publications

The ampullariid Pomacea urceus uses its ctenidium and lung in respiration. The snails reach the surface with their siphon and ventilate their lung by withdrawing their head-foot in a pumping action. The lung gas also serves to change the buoyancy of the snails. After a ventilation a snail does not necessarily return to the same buoyancy level. They may achieve overall specific gravities of <1 to > 1 after a ventilation. They may remain submerged (s.g. > 1) or float (s.g.

A Cytogenetic Study Of Xx/Xy Chimerism And Other Anomalies Of Bos Taurus In A Sampled Dairy Herd, Ferne M. Rogers

Masters Theses

The establishment of normal chromosomal patterns for a wide range of plants and animals has led to the recognition of abnormalities as well as their relationship to phenotypic irregularities. Research dealing with the expression of human karyotype is of prime interest; but, closely rivaling that is the genetic study of domestic animals which are of economic importance to man.

One observed anomaly which has come under scrutiny by cytogeneticists is that of the female member of a heterogeneous bovine twin pair, the freemartin. This is a sterile animal with internal morphology showing varying degrees of intersex. Cytogenetic studies reveal XX/XY …

Modification Of Ontogenic Expression Due To Relocation Of The Ry+ Gene In Drosophila Melanogaster, Allen A. Badgett Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ry⁺ gene of Drosophila melanogaster and its associated enzyme, xanthine dehydrogenase, were employed in an analysis of the relationship between regulation and the location of a gene in the genome. Enzyme assays as an indication of gene activity were performed on genotypes containing zero, one and two doses of ry⁺ genes. Xanthine dehydrogenase activity of rosy genes in normal and relocated positions was determined during development.

The results indicate: 1) the gene ry⁺ is differentially active during ontogeny; 2) the activity during ontogeny is proportional to the number of ry⁺ genes present in the genome; …

Later Mating Improves Lambing Results, R J. Suiter

Journal of the Department of Agriculture, Western Australia, Series 4

Ovulation studies in Western Australia have indicated that increased lambing percentages in crossbred and Merino ewes could be expected from mating in February-April rather than December- January.

Such increases have been demonstrated in time of lambing trials with crossbred ewes, but had not been seen in Merino flocks until recently.

This report summarises the results of time of lambing trials with Merinos carried out at the Merredin and Wongan Hills Research Stations between 1963 and 1969.