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Full-Text Articles in Animal Sciences

Mathematical Equations Describing Chick Performance And Carcass Composition As A Function Of Diet Protein And Energy Levels, Naiyana Nakhata Jan 1978

Mathematical Equations Describing Chick Performance And Carcass Composition As A Function Of Diet Protein And Energy Levels, Naiyana Nakhata

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Previous work at Utah State University determined minimum levels of different nutrients that would produce the maximum rate of gain or gain/feed ratio by feeding graded levels of the nutrients. Fitting broken lines to the data from work with one nutrient tended to underestimate the minimum requirement for that nutrient. It appeared that the response was not linear up to the level required to give maximum performance as the "broken line" approach to estimating the requirement assumes. It seemed worthwhile to try to describe the relation between ration level of a nutrient and chick performance by means of a mathematical …


Possible Impacts Of The Expected Shift From Cow-Calf To Cow-Calf-Yearling Enterprises On Beef Production And Beef Prices, Suliman H. Abdalla May 1977

Possible Impacts Of The Expected Shift From Cow-Calf To Cow-Calf-Yearling Enterprises On Beef Production And Beef Prices, Suliman H. Abdalla

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Retention of young cattle and marketing older cattle from the range has been suggested as one of the profitable means of adjustment for the cow-calf operator. This study was to determine the impacts of the shift from cow-calf ranching operation to cow-calf-yearling operation on the feed energy budget of the ranch, cow herd size, beef production and market price of beef. Ten alternative livestock management options involving cow-calf-yearling operations were tested for these impacts, using two representative Utah size ranches (150 and 300 cow ranches).

The extra feed needed to accomodate the increased number of yearlings and the decrease required …


Economics Of Carry-Over Forage Production, Increased Grazing Season Length, And Increased Livestock Production From Rangeland Fertilization, Dean L. Roberts Jr. May 1977

Economics Of Carry-Over Forage Production, Increased Grazing Season Length, And Increased Livestock Production From Rangeland Fertilization, Dean L. Roberts Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper entails the economic and biological responses of both rangeland grasses and livestock grazing rangeland grasses to nitrogen fertilization. Five sites received graduated rates of fertilizer in previous studies. Analysis showed all sites failed to exhibit a significant carry-over response to fertilization. Determination of optimum rate or optimum reapplication schedule was not possible due to residual nitrogen present in the soil. Spring application of fertilizer produced the greatest returns from one site while the other site studied failed to produce a profitable response from either spring or fall application.

Calf weight gains were shown to be curvilinear and resulted …


An Economic Analysis Of Predation Control And Predatory Sheep Losses In Southwestern Utah, R. Garth Taylor May 1977

An Economic Analysis Of Predation Control And Predatory Sheep Losses In Southwestern Utah, R. Garth Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To provide accurate data concerning sheep losses resulting from predation, a verification study of sheep predation was initiated in March 1972 in the Cedar City area of Utah. In cooperation with the Cedar City Wool Growers Association and Southern Utah State College Experimental Farm, ten sheep ranches were chosen as sample operations, forming the data base for the initial phase of the study (1972-1974).

Cooperating ranchers were asked to promptly report all sheep carcasses or injured sheep, so that an examination could immediately be made to ascertain the cause of death or injury. Daily horseback searches were also conducted on …


Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr. May 1977

Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rodent densities were estimated in the major vegetation types of the Snake River Birds of Prey Natural Area in 1975 and 1976 by a combination of live-trapping and kill-trapping. Only deer mice (Peromyscus maniculatus) were numerous enough to permit reliable density estimates. Relative densities of other rodent species were indicated by kill-trap capture rates. Densities of deer mice correlated well (r = 0.99) with kill-trap capture rates. The use of kill-trapping in place of live-trapping in 1976 permitted extensive sampling throughout the 1930 km2 study area. Differences were found among the major vegetation and land-use types in …


Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza May 1977

Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to provide data on responses of Angora goats and blackbrush (Coleogyne ramosissima) to a biological manipulation program. Blackbrush utilization levels averaged 30, 16, and 6 percent (545, 367, and 147 kg per hectare) for the heavily, moderately, and lightly browsed pastures, respectively; removal rates of 77, 38, and 19 percent (1164, 582, and 291 kg per hectare) were projected.

Statistically significant differences in body weight loss (P=0.052) were noted for goats browsing in different replications. Goats lost an average of 14 and 19 percent of body weight in replications one and two, …


Breeding Biology And Pesticide-Pcb Contamination Of Western Grebe At Bear River Migratory Bird Refuge, Mark L. Lindvall May 1976

Breeding Biology And Pesticide-Pcb Contamination Of Western Grebe At Bear River Migratory Bird Refuge, Mark L. Lindvall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The breeding biology of western grebe was studied at Bear River Migratory Bird Refuge, Utah in 1973 and 1974. More than 300 nests were located and data gathered on nesting habitat and success. Western grebe at Bear River selected nest sites for nearness to open water of approximately 30 em in depth. At least one young was hatching in 21 percent of the nests. Avian predation and abandonment of nests following drops in water levels caused the greatest loss of nests. Chlorinated hydrocarbons monitored in western grebes showed DDE, DDD, PCB, 1260, and PCB 1254 levels in 24 breast muscle …


The Horse Population Of Utah And Its Impact, Scott Stewart Mckendrick May 1976

The Horse Population Of Utah And Its Impact, Scott Stewart Mckendrick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

PART I

The horse numbers of Utah had not been accurately counted since the early 1960's. It was estimated that horse and pony numbers were reaching heights as recorded before the age of tractors and automobiles. Horsemen in Utah were asking for financial assistance for public horse facilities from the Utah legislature. The first part of this study was to survey the horse population to determine an accurate count of Utah horses.

PART II

In order to be satisfied that the horse industry deserved the spending of public funds, it was necessary to know the economic contribution of the horse …


Effects Of Group, Individual, And Isolated Rearing Of Dairy Calves On Weight Gain And Social Development, Val D. Warnick May 1976

Effects Of Group, Individual, And Isolated Rearing Of Dairy Calves On Weight Gain And Social Development, Val D. Warnick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Thirty-six dairy calves were observed for four months to determine the effect of three housing methods, group, individual and isolated on body weight gain, feed consumption, age when started to consume grain, daily activity patterns, open field test of behavior and social rank. Six calves were assigned to each of the three treatments in two separate trials of eighteen calves. These calves were raised in their treatment for approximately two months and then weaned and placed together in a group of eighteen for two more months.

Treatments ranked in order from high to low according to least squares means for …


Multiple Hemoglobins In Rainbow Trout, Salmo Gairdneri, And Cutthroat Trout, Salmo Clarkii, Jeffrey Carl Braman May 1976

Multiple Hemoglobins In Rainbow Trout, Salmo Gairdneri, And Cutthroat Trout, Salmo Clarkii, Jeffrey Carl Braman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nine hemoglobins from adult rainbow trout have been isolated by starch gel electrophoresis using a Trisborate buffer system, pH 8.7. Six fast and two slow anodally migrating hemoglobins, and one slow cathodally migrating hemoglobin were observed in all specimens.

The nine hemoglobins have been purified by DEAE cellulose ion exchange chromatography followed by starch gel electrophoresis.

The subunit structure of each purified hemoglobin has been partially examined by gel electrofocusing (GEF) in .5 percent polyacrylamide gels containing 8M urea and lmM dithiothereitol (DTT). Tetrameric combinations of one, two, three, and four polypeptide chains are present.

Twelve hemoglobins have been isolated …


Food Interactions Between Utah Prairie Dogs And Cattle, Dennis Crocker-Bedford May 1976

Food Interactions Between Utah Prairie Dogs And Cattle, Dennis Crocker-Bedford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the food interactions between Utah prairie dogs (Cynomys parvidens, Allen) and cattle (Bos taurus). During 1974 and 1975, three prairie dog colonies near Panguitch, Utah, were studied intensely: "Oldfield" was chosen to represent colonies near fields of alfalfa (Medicago sativa); "Lowercrested" was chosen to represent colonies below 2,200 meters above sea level (a.s.l.) which were not near alfalfa, and "Uppercrested" was chosen to represent colonies above 2,200 meters a.s.l. which have been planted with crested wheatgrass.

Visual observations were made of Utah prairie dogs to determine their diets. Livetrapping of prairie …


Feeding Behavior Of Pen Reared Mule Deer Under Winter Range Conditions, Michael A. Smith May 1976

Feeding Behavior Of Pen Reared Mule Deer Under Winter Range Conditions, Michael A. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the feeding responses of mule deer to a system of spring livestock grazing. The specific purposes were 1) to determine botanical composition of diets selected by mule deer on a winter range subjected to previous spring grazing by sheep compared to one with no sheep grazing and 2) to develop a basis for predicting selection of individual plants by deer, based on physical characteristics of the plants and the species and physical proximity of associated plants.

The study was conducted within the framework of a completely randomized experimental design with two treatments. Variables controlled for each unit …


Forage Selection And Nutrition Of Sheep And Goats Grazing In The Tunisian Pre-Sahara, Rudolfo Ricardo Griego May 1976

Forage Selection And Nutrition Of Sheep And Goats Grazing In The Tunisian Pre-Sahara, Rudolfo Ricardo Griego

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nomadic pastoralism has been the traditional method of utilizing grazing resources in arid and semi-arid regions of Africa. However, increased sedentarization accompanied by growing human and animal populations during the past two decades is thought to be accelerating the desertification process, or desert expansion. The specific interactions of the grazing animal with this process has been speculated upon but not studied in detail. A comparative study was initiated during the spring grazing season of 1974 to determine sheep and goat nutritional and production responses, as well as patterns of vegetative selection and utilization under the pastoral system currently employed in …


The Reproductive Cycle Of Male Uinta Ground Squirrels And Its Relationship To Pineal N-Acetyltransferase And Monoamine Oxidase In The Testes, Hypothalamus And Pituitary, Robert Alexander Palmer May 1975

The Reproductive Cycle Of Male Uinta Ground Squirrels And Its Relationship To Pineal N-Acetyltransferase And Monoamine Oxidase In The Testes, Hypothalamus And Pituitary, Robert Alexander Palmer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study was made of the reproductive cycle of male Uinta ground squirrels (Spermophilus armatus) during the activity seasons of 1973 and 1974 and during the aestivation/hibernation (A/H) period of 1973-1974. Physiological data collected were compared to changes in monoamine oxidase (MAO) activity of the testes, pituitary and hypothalamus and to pineal N-acetyltransferase activity.

Male Uinta ground squirrels began emerging from their burrows on April 12, 1973, and April 8, 1974, with average body weights of 302 g and 301 g, respectively. Body weight did not increase greatly during breeding, but rose rapidly to over a 500 g …


Relationships Between Teat Shape, Teat Erosion, California Mastitis Test, And Milk Production In A Large Dairy Herd, John Sephen Malan May 1975

Relationships Between Teat Shape, Teat Erosion, California Mastitis Test, And Milk Production In A Large Dairy Herd, John Sephen Malan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Data were collected from a 1,000 cow commercial dairy unit during three different time periods to determine the interrelationships between teat shape, teat erosion, mastitis (as measured by the California Mastitis Test and somatic cell counts), and milk production.

Results showed no relationship between teat shape or teat end erosion and milk or fat production. The relationship between teat end erosion and mastitis appeared to be masked by the high level of teat erosion. There was an indication that cows with flat and cone shaped teat ends were prone to higher California Mastitis Test scores than cows with pointed, round, …


A Comparison Of Three Methods Used To Analyze Pronghorn Antelope Diets, Leonard J. Shandruk May 1975

A Comparison Of Three Methods Used To Analyze Pronghorn Antelope Diets, Leonard J. Shandruk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An increasing interest in fecal analysis as a method of determining diets of herbivores prompted research to determine if this method could be used successfully to determine diets of pronghorn antelope found in Utah's cold desert rangelands. In addition to fecal analysis, quantitative estimates of pronghorn diets were derived from rumen analysis and feeding site observations. Rumen samples were analyzed by three different methods: (1) microscopic, (2) gravimetric, and (3) point frame. In addition to field experiments, samples from a feeding trial with a diet of known composition were used to determine whether or not differential digestion of plant epidermis …


An Analysis Of Sound Communication In The Water Vole, Microtus Richardsoni (Rodentia: Microtinae), Dane R. Tang May 1975

An Analysis Of Sound Communication In The Water Vole, Microtus Richardsoni (Rodentia: Microtinae), Dane R. Tang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Adult members of the species Microtus richardsoni were used to study the importance of acoustic communication in these voles. Tests were run with single individuals and nonbreeding pairs of voles to obtain recordings and sonagraphs of sounds emitted during exploration of a new cage, agonistic encounters, encounters with a potential predator and in response to miscellaneous aversive stimuli. Of the four groups of tests conducted, sounds were used by M. richardsoni during the last three. The results of this study showed that the water vole emitted ten different call types or sounds. These sounds were separated by similarity into Group …


An Evaluation Of In-Stream Structures Designed To Provide Fish Habitat, Charles H. Call Jr. May 1974

An Evaluation Of In-Stream Structures Designed To Provide Fish Habitat, Charles H. Call Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In-stream concrete structures were studied through model tests and river tests. The model studies indicated that four designs provided good habitat in the model stream. These structures were the inverted weir, the "V" structure, the slab with legs and the cylinder. Through the river studies it was determined that these structures did not influence enough of the total river area to be effective in providing good fish habitat. Also an appreciable amount of yearly maintenance would be required to free the structures from silting in, debris, and vandalism. The slab with legs was the only promising structure.


Vocalizations In A Population Of Green-Tailed Towhees (Chlorura Chlorura), Timothy Andrus Burr May 1974

Vocalizations In A Population Of Green-Tailed Towhees (Chlorura Chlorura), Timothy Andrus Burr

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies of vocalizations in a montane population of Green-Tailed Towhees were conducted during the summer months of 1971 and 1972 in Cache County, Utah. The song and call repertoiries of 10 breeding pairs were recorded and analyzed on a sound spectograph.

Males averaged 8.7 different song and 18.2 different not types. Song variation on the population level is high (58 different songs) but the sharing of these songs among the males is low (22.4). Populational note structure is equally diverse but reveals a greater degree of sharing (75%).

Both males and females used three calls, the meow, tick, …


Manufacture Of Monterey Cheese From Preacidified Milk, Faisal O. Mohamed May 1974

Manufacture Of Monterey Cheese From Preacidified Milk, Faisal O. Mohamed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whole milk acidified to pH 5.3 with hydrochloric acid was used for the manufacture of Monterey cheese. The milk was inoculated with one and one-half percent lactic starter and set with 12.5 ml rennet per 1000 pounds of milk. Normal washing treatments resulted in cheese with moisture in excess of 44 percent. Moisture content was brought below 44 percent by using wash water at a temperature such that the water-curd-whey mixture was 35 C. The pH of cheese made by preacidification was all between 5.21 and 5.09. No acid defects were encountered. Preacidification eliminated chance of spoilage or losses caused …


Nutrition Of Sheep Grazing Foothill Big Game Range In Spring, Kurt J. Kotter May 1974

Nutrition Of Sheep Grazing Foothill Big Game Range In Spring, Kurt J. Kotter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sheep with esophageal fistulas were used to determine the daily intake, nutritive content and digestibility of forage at three periods and two stocking intensities during the spring of 1972 on a typical foothill range in northern Utah.

Heavy grazing under a season-long regime did not influence the concentrations of dietary chemical components when compared to moderate grazing; however, it did depress the digestibility of cellulose and organic matter. There was a significant decline in the dietary chemical components due to forage maturation. Digestibility of organic matter and cellulose were significantly higher in the early spring as compared to late spring. …


Effects Of Exercise On Serum Lactate Dehydrogenase Activity Of Catchable-Size Hatchery Rainbow Trout, Salmo Gairdneri, Gerlad T. Klar May 1973

Effects Of Exercise On Serum Lactate Dehydrogenase Activity Of Catchable-Size Hatchery Rainbow Trout, Salmo Gairdneri, Gerlad T. Klar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Effects of exercise and the relative condition of exercised fish were viii evaluated for two strains of rainbow trout. Circular tanks fitted with a paddle were used to continuously exercise the fish and a stamina tunnel was used to evaluate the condition of exercised trout. Trout were exercised continuously at one fish-length per second and one-half fish length per second. Serum LDH activity in Shephard-of-the-Hills (Missouri) rainbow trout acclimated to 10 C increased two fold during the first four days of exercise. Serum LDH activity returned to control levels by the tenth day of exercise. Serum LDH activity in Shephard-of-the-Hills …


Mechanisms Of Population Regulation In Confined Colonies Of Peromyscus Maniculatus (Wagner) And The Response To Exploitation, Donna Corn Olsen May 1973

Mechanisms Of Population Regulation In Confined Colonies Of Peromyscus Maniculatus (Wagner) And The Response To Exploitation, Donna Corn Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wild-trapped and laboratory-reared Peromyscus maniculatus (Wagner) were raised as confined colonies indoors with various stocking densities ranging from 0.026 to 0.100 mice per sq. ft. in pens of 40, 77, and 154 sq. ft. The animals were individually tagged and all pens were censused at weekly or semi-monthly intervals to record animals present, body weights, food consumption, and overt reproductive condition. At the termination of each experiment, all mice were necropsied and organ weights of gonads and adrenals recorded. Histological sections were made of the testes and ovaries. Half the colonies were subjected to density-independent exploitation by removal of 50% …


Fish Production And Movements In The Lower Logan River, Utah, Eric P. Bergersen May 1973

Fish Production And Movements In The Lower Logan River, Utah, Eric P. Bergersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Following the abatement of domestic sewage pollution xii in the lower Logan River , the fish population was investigated in terms of abundance, growth, fecundity, production, mortality, age class structure, species diversity, distribution and movements during 1970 and 1971.

Three general groupings of fish were identified in the study area on the basis of species composition, abundance and distribution using a cluster analysis technique. These were located in 1) the tributary stream (7-Mile Creek) which previously transported sewage to the river and 2) above and 3) below 7-Mile Creek in the main stream of the Logan River. A "transition" population …


Overwinter Mortality Of Trout In Temple Fork Of The Logan River, Daniel Richard Cerven May 1973

Overwinter Mortality Of Trout In Temple Fork Of The Logan River, Daniel Richard Cerven

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were to determine the mortality rates of trout in Temple Fork of the Logan River during the winter of 1970-1971 and to identify factors related to trout mortality.

Trout in seven 100-m sections of the 7 3-km stream were sampled by electroshocking in October, December, February, and April. Captured trout were weighed measured and tagged or fin-clipped. Scale samples were taken for age determinations and the fish were returned to the creek.

Water temperature, snow cover, and anchor ice were monitored.

Three species of trout were found in Temple Fork: brown, rainbow, and cutthroat trout. …


Factors Affecting Feeding Habits Of Sheep Grazing Foothill Ranges Of Northern Utah, Farid D. Iskander May 1973

Factors Affecting Feeding Habits Of Sheep Grazing Foothill Ranges Of Northern Utah, Farid D. Iskander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An experiment was designed to study the effects of forage availability, season and intensity of grazing, and distribution and behavior of sheep on their forage preferences. Three grazing periods of 15 days each were used to study the effect of season. Each grazing period included a heavy and a moderate stocking intensity. Pastures were divided by a grid into 30.48 m x 30.48 m compartments. Each compartment was sampled for botanical composition of available herbage prior to and after grazing. Esophageally fistulated sheep were allowed to graze freely and positions of individual sheep with respect t o compartments were recorded …


Economics Of Carry-Over Production And Increased Grazing Season Length Due To Range Fertilization, Paul W. Mccormick May 1973

Economics Of Carry-Over Production And Increased Grazing Season Length Due To Range Fertilization, Paul W. Mccormick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper entails the economic and biological interpretation of the response of rangeland grasses to nitrogen fertilization. Six sites throughout Utah received graduated rates of fertilizer. The coefficients of the production function
Y = a + bN - cN2
were identified.

An initial production and a carry-over response were identified on sites receiving greater than ten inches of annual precipitation. Optimum fertilization rates may be identified by equating the marginal physical product to the ratio of the price of nitrogen to the price of the forage.

Forage response to nitrogen is reflected strongly in the early growth response in …


A Computerized Performance Record Keeping System For Beef Cattle In Utah, John J. Pierce May 1973

A Computerized Performance Record Keeping System For Beef Cattle In Utah, John J. Pierce

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A computer program was developed at Utah State University (USU) to aid in obtaining a more complete individual performance record keeping system for beef cattle in Utah. Some computer programs for beef cattle records presently exist but a program was needed that was readily available to the USU animal science extension and resident staff.

The program was written in FORTRAN for use on the Burrogh 6700 computer located at the Utah State University Computer Center. It was designed to read input data for individual animals, perform various calculations (i. e. days of age, adjusted weaning weight and weaning weight ratio), …


Impact Of The Black-Tailed Jackrabbits (Lepus Californicus) On Vegetation In Curlew Valley, Northern Utah, Mark Westoby May 1973

Impact Of The Black-Tailed Jackrabbits (Lepus Californicus) On Vegetation In Curlew Valley, Northern Utah, Mark Westoby

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The interrelations of black-tailed jackrabbits and the desert-shrub vegetation on which they were feeding were studied in Curlew Valley, Northern Utah. The vegetation was described as a three-cornered continuum, the corners being types dominated respectively by Artemisia tridentata, Atriplex confertifolia, and Sarcobatus vermiculatus.

Jackrabbit diet was studied by microscopic analysis of plant fragments in stomachs from shot animals. The method was inaccurate, apparently because the ratio of identifiable tissues to all ingested tissues was very low, and varied between plant taxa, and seasonally. This problem seems intractable for desert shrub vegetation.

The diet was similar to that …


An Evaluation Of Stress Induced Mortality Of Stocked Catchable-Sized Rainbow Trout In Temple Fork Of The Logan River, Robert Earl Gresswell May 1973

An Evaluation Of Stress Induced Mortality Of Stocked Catchable-Sized Rainbow Trout In Temple Fork Of The Logan River, Robert Earl Gresswell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The level of stress imposed by population pressure, handling and live transportation on planted catchable-sized rainbow trout in a northern Utah stream was examined. Production of adrenocorticotrophin, as measured by interrenal ascorbic acid and serum cortisol levels, did not occur in transported or planted fish.

Dead or moribund fish collected from stream or live boxes comprised 13 percent of the 2,000 fish planted. Aeromonas salmonicida, the causative agent of furunculosis, was isolated from 41 percent of 106 moribund fish sampled. In addition, 39 percent of the samples exhibited bacterial growth other than A. salmonicida. Apparently, handling, transportation, and planting did …