Digital Commons Network^™

An Economic Analysis Of Prairie Dog Control, Alan Robert Collins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Prairie dog control was found to be economically feasible on the Conata basin in South Dakota with future annual maintenance control to prevent re-invasions. The large difference between the present net worth values of the two viewpoints ($2587 for the U.S. Forest Service acting as an agent of the sovereign and $109,011 for the ranchers) was due to the added costs of environmental considerations included in the U.S. Forest Service control program, but assumed not to be included in control by ranchers. In order for prairie dog control to remain economically feasible, annual maintenance control for the U.S. Forest Service …

Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperatures selected seasonally by adult mountain whitefish were measured in the laboratory in a horizontal gradient. Final preferendum estimates, based on acute (3-hour) preference tests conducted with fish acclimated to 5, 10, and 15 C each season, were 17.7 C (pre-spawning), 11.9 C (post-spawning), 9.9 C (winter), and 16.3 C (spring). Seasonal influence on temperature selection was evident on the basis of differences in final preferenda, covariance analysis of responses of laboratory-acclimated fish, and temperature selection by fish held at ambient river temperatures. Post-spawning and winter groups selected lower temperatures than did pre-spawning and spring groups. Pre-spawning fish selected temperatures …

Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Domestic goats were used to modify the growth form of blackbrush, a spinescent shrub occurring in nearly monospecific stands on several million hectares of rangeland in the southwestern United States. The objective of this research was to evaluate goat browsing as a means of improving these rangelands for cattle. Winter goat browsing stimulated spring twig growth from basal and axillary buds which resulted in increased production.

Twig production by heavily browsed plants (>95 percent removal of current season's twigs) was a function of precipitation, soil depth, branch location on the plant, and period of rest after browsing. As precipitation …

Effect Of Toxaphene On Collagen Synthesis In Fish Tissue: Organ Culture Studies And Prolyl Hydroxylase Activity Assay, Charles Franklin Luke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Toxaphene is reported to cause defects in the collagen of fish. Chronic exposure to toxhaphene weakens the backbone of fish by decreasing the amount of collagen and usually increasing the amount of calcium in the bone which results in a more brittle and fragile bone.

We investigated the possible direct action of toxaphene on collagen synthesis by exposing vertebral and swim bladder organ cultures obtained from unexposed rainbow trout (Salmo gairdneri) fingerlings to the same lot of toxaphene found to cause this defect in vivio. Collagen produced by these organ cultures was measured by: (1) total ^{3 …}

Effect Of Rain Leaching On Chemical Composition Of Alfalfa Hay, Mercedes M. Garcia De Hernandez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Yield and chemical changes of second-cutting alfalfa hay treated with artificial rain were determined in a 2 x 3 x 2 factorial experiment. Factors were 2 stages of maturity (1 = late vegetative; 2 = early bloom), 3 levels of artificial rain applied (1 = no rain; 2 =low or approximately 5 mm; 3 = high or approximately 20 mm), and 2 times of applying artificial rain (1 = when drying forage was 40-60% dry matter; 2 = when drying forage was 60-75% dry matter). Thirty samples of alfalfa were collected at the 2 stages of maturity when the alfalfa …

Models For Estimating Energy And Protein Utilization For Feeds, Muhammad Fadel Wardeh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Data on the proximate nutrient content of feedstuffs, digestibility and energy utilization available from the International Feedstuffs Institute (Utah State University) were used to develop mathematical models for estimating energy and protein utilization of five classes of feedstuffs for various kinds of animals.

Classes of feedstuffs were subdivided into more related subclasses. Furthermore, data from all feeds were pooled together then subgrouped into more related subgroups in an attempt to gain high precision in prediction of digestible proximate nutrients and TDN from a single chemical entity by the use of simple regression models (Y = bo + b₁x …