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Full-Text Articles in Life Sciences
The Effects Of Age And Induction On Cockroach Mixed Function Oxidase Activity And Cell Morphology, Richard L. Turnquist
The Effects Of Age And Induction On Cockroach Mixed Function Oxidase Activity And Cell Morphology, Richard L. Turnquist
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Female American cockroaches showed definite age-dependent changes in levels of activity of the microsomal mixed function oxidase chain. Cytochrome P-450 levels, EPN-detoxication, and p-nitroanisole O-demethylation activities were very low in young adult insects but increased steadily reaching a peak at about 100 days in fat body and at about 90 days in midgut and hindgut. The activities then declined rapidly reaching levels of young insects at about 130 to 140 days of age. NADPH-NT-reductase activity was high in young insects and declined during the first few weeks of adult life. This activity too showed a peak at about …
Influence Of Age On Milk Production Of Holstein Cows In Utah, Marvin R. Green
Influence Of Age On Milk Production Of Holstein Cows In Utah, Marvin R. Green
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Production of dairy cows is influenced by many factors, among which are: genetics, nutrition, management, disease and age. Most of these factors can be modified to maintain a high level of production. Age, however, is beyond the influence of mankind; therefore, it is important to understand the effect of age on milk and butter-fat production.
The Use Of Branchiostegal Rays To Determine Age Of Lake Trout Salvelinus Namaycush Walbaum, Ross Vivian Bulkley
The Use Of Branchiostegal Rays To Determine Age Of Lake Trout Salvelinus Namaycush Walbaum, Ross Vivian Bulkley
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Any method used in aging fish must fulfill certain requirements to be satisfactory. If the method is inaccurate, naturally little reliance can be placed upon its use. If considerable study of the method and much practice are required before accurate readings can be obtained, the method will not come into widespread use. The requirements of an aging method, then are that it must be accurate and comparatively easy. The scale method for aging lake trout (Salvelinus namaycush Walbaum) unfortunately does not fulfill these requirements. It has always been difficult to tell the age of lake trout by the examination …
Age And Growth Of The Utah Chub, Gila Atraria (Girard), In Panguitch Lake And Navajo Lake, Utah, From Scales And Opercular Bones, John M. Neuhold
Age And Growth Of The Utah Chub, Gila Atraria (Girard), In Panguitch Lake And Navajo Lake, Utah, From Scales And Opercular Bones, John M. Neuhold
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Previous literature indicates the opercular bone as a useful tool for the determination of age and growth of fish. The reliability and validity of this method is tested for two populations of Utah chub. Age and growth are calculated for 222 Utah chub collected from Panguitch Lake and 212 Utah chub collected from Navajo Lake, southern Utah, in 1952-1953 from both scales and opercular bones. Scales are measured with the aid of a projector. Opercular bones are measured directly. The center of growth of the opercular bone is posterior to the posterior lip of the fulcrum. Correction for curvature is …
The Opercular Bone As An Indicator Of Age And Growth Of The Carp Cyprinus Carpio Linnaeus, William J. Mcconell
The Opercular Bone As An Indicator Of Age And Growth Of The Carp Cyprinus Carpio Linnaeus, William J. Mcconell
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
As part of an investigation of the non-game fish resources of Utah, a study of the age and growth rate of the carp was instituted. A preliminary investigation indicated that the opercular method was superior to several other methods of determining age and growth in the carp. Age and growth were calculated from the opercular bones of 330 carp collected at Ogden Bay Refuge in 1950-51. Distances to annuli were measured directly. The relationship between the posterior radius of the opercular bone and the standard length of the carp was curvilinear. Past growth was calculated with a logarithmic nomograph. Expected …