No description available.

The objective of this research is to analyze the relationship between environ-mental heat exchange and vascular response in the pallid bat wing during systemicheating and to develop a simplied model of heat transfer for theoretical analysis.During heating experiments, metabolic activity, body temperature and alterations invessel diameter and blood ow were monitored. This research is very signicant, asit will correlate thermoregulation and vascular response in a way that has not beenstudied before.The wing of the pallid bat is selected because the microvascular bed performssimilar functions as that of the human skin in terms of thermoregulation; understand-ing vascular response to heat or cold allows to analyze vascular function, or arterialhealth, a response that is altered at early stages of several diseases in humans. Athigh body temperatures, bats can dissipate heat through their wings; the bat wingserves as a thermal window where heat exchange is determined by local blood owand vascular response in the wing.For this study, a lumped mathematical model to calculate body and skin tem-perature alterations in response to changes in environmental conditions has beendeveloped. In order to formulate this model, experiments have been proposed wherethe pallid bat is subjected to dynamic systemic heating with and without the wingextended. By having the wing extended outside a metabolic chamber during heating,the bats were able to maintain an equilibrated body temperature; having the wing enclosed caused body temperature to increase rapidly. The experiments were designedto obtain correlations between systemic and vascular responses and therefore learnabout the thermoregulatory mechanisms of the pallid bat.Results from experiments following Animal Use Protocols 2006-253 and 2007-110indicate that vascular responses to environmental temperature changes (changes inTchamber) maintain or reduce body temperature to basal conditions. Vessel diameter,centerline velocity, blood ow and heat ux increase with Tchamber therefore deliveringa greater volume of blood to the bat wing and increasing heat exchange with theenvironment. The positive responses in the wing to Tchamber signify that the pallidbat is regulating its body temperature as had been expected.

The objective of this research is to analyze the relationship between environ-mental heat exchange and vascular response in the pallid bat wing during systemicheating and to develop a simplied model of heat transfer for theoretical analysis.During heating experiments, metabolic activity, body temperature and alterations invessel diameter and blood ow were monitored. This research is very signicant, asit will correlate thermoregulation and vascular response in a way that has not beenstudied before.The wing of the pallid bat is selected because the microvascular bed performssimilar functions as that of the human skin in terms of thermoregulation; understand-ing vascular response to heat or cold allows to analyze vascular function, or arterialhealth, a response that is altered at early stages of several diseases in humans. Athigh body temperatures, bats can dissipate heat through their wings; the bat wingserves as a thermal window where heat exchange is determined by local blood owand vascular response in the wing.For this study, a lumped mathematical model to calculate body and skin tem-perature alterations in response to changes in environmental conditions has beendeveloped. In order to formulate this model, experiments have been proposed wherethe pallid bat is subjected to dynamic systemic heating with and without the wingextended. By having the wing extended outside a metabolic chamber during heating,the bats were able to maintain an equilibrated body temperature; having the wing enclosed caused body temperature to increase rapidly. The experiments were designedto obtain correlations between systemic and vascular responses and therefore learnabout the thermoregulatory mechanisms of the pallid bat.Results from experiments following Animal Use Protocols 2006-253 and 2007-110indicate that vascular responses to environmental temperature changes (changes inTchamber) maintain or reduce body temperature to basal conditions. Vessel diameter,centerline velocity, blood ow and heat ux increase with Tchamber therefore deliveringa greater volume of blood to the bat wing and increasing heat exchange with theenvironment. The positive responses in the wing to Tchamber signify that the pallidbat is regulating its body temperature as had been expected.

No description available.

Thesis (M.S.)--University of Nevada, Reno, 2007. / "December, 2007." Includes bibliographical references. Online version available on the World Wide Web.

Pallid sturgeon (Scaphirhynchus albus) is a native North American fish that was listed as a federally endangered species in 1990 due to failure in spawning and recruitment, perhaps as a result of human modifications to their habitat. The upper Missouri River basin pallid sturgeon have been shown to be genetically distinct from other pallid sturgeon. Since there has been no natural recruitment in the upper Missouri River for several decades, perpetuation of this genetically distinct unit is reliant on propagation using remaining wild fish as broodstock. The expense associated with acquiring unique individuals from the remaining wild broodstock is causing wild collection to become a less viable option each year. It has been proposed that rearing progeny of wild broodstock fish in a hatchery setting as captive broodstock may be feasible alternative to wild collections. The genetic risks associated with the creation of a captive broodstock need to be investigated and a captive management plan needs to be developed prior to the implementation of a captive broodstock program. The relatedness values and the effective population size for the wild caught founders were determined by genotyping wild upper Missouri River pallid sturgeon at 16 previously developed microsatellite loci. The founding wild broodstock were shown to encompass an ample amount of genetic variation and a sufficiently large effective population size. The broodstock currently housed as Gavin's Point National Fish Hatchery can be exclusively used for the propagation of pallid sturgeon to be stocked in the upper Missouri River with the caveat that descendents from each wild fish will be spawned in the future and that the reproductive variance of the broodstock be controlled to maximize Ne and thus reduce inbreeding.

The purpose of this project was to develop inexpensive, standardized, and high throughput Single Nucleotide Polymorphism (SNP) markers that discriminate between pallid (Scaphirhynchus albus) and shovelnose (S. platorynchus) sturgeon for use as a larval identification tool. A total of 67 polymorphic sites was identified in DNA sequences from three genes: Recombination Activating Gene-1, Beta Actin, and Beta-2-Microglobulin. Allele frequencies from the 10 most variable SNPs were characterized for both pallid and shovelnose sturgeon in three geographically separated populations throughout the range of the pallid sturgeon. To create a standardized method of genotyping SNPs for larval pallid and shovelnose sturgeon, 5' nuclease allelic discrimination (TaqMan) assays were designed for two unlinked SNPs that exhibited the greatest allele frequency differences between species. A power analysis compared these SNP loci and their diagnostic power for species discrimination compared to sixteen microsatellite loci currently used for species discrimination (Schrey et al. 2007) One SNP locus was the most powerful marker for species identification in the upper and middle Missouri River. This study provides practical genetic tools for species discrimination between pallid and shovelnose that will facilitate understanding addressing questions that were previously too costly, labor intensive or technically challenging to answer.

Growth rates and diet patterns for sympatric pallid sturgeon Scaphirhynchus albus and shovelnose sturgeon S. platorynchus throughout the Missouri River and lower Mississippi River were examined. Pallid sturgeon growth in the Great Plains Management Unit (GPMU) was slower than in other river reaches until age 9 and pallid sturgeon from the Interior Highlands Management Unit (IHMU) and Coastal Plain Management Unit (CPMU) did not differ. No differences in growth between management units were detected for shovelnose sturgeon. Observed differences in growth between pallid sturgeon and shovelnose sturgeon were generally dependent upon which growth model was used, but pallid sturgeon were typically larger after age 4. Diet is considered a primary driver of growth. Stable isotopes are capable of examining diet over longer time periods than gut content studies, but that time frame is dependent on which tissue is selected. Using fin clips, diet of both pallid sturgeon and shovelnose sturgeon was evaluated via stable isotopes. Pallid sturgeon and shovelnose sturgeon trophic position (TP) was influenced by management unit. There was a slight, but not significant, latitudinal trend with pallid sturgeon TP increasing by approximately one full TP between the GPMU and CPMU. Pallid sturgeon growth was negatively related to TP but was unrelated to δ13C in the Missouri River. Shovelnose sturgeon growth was not related to TP, but was negatively related to δ13C in the Missouri River. Dissimilarity in TP combined with differences in δ13C between species suggests low diet overlap between these sympatric species, and neither species should be used as a surrogate for the other for prey consumption studies. Further, pallid sturgeon differences between the GPMU and the rest of the management units suggest that individuals from the GPMU could be managed separately from those in other management units.

Research developing artificial propagation, husbandry, and nutrition of sturgeon species has developed greatly since the collapse of the Caspian Sea fisheries in the 1980s. Sturgeon species are commercially prized for their unfertilized roe which is marketed as the delicacy, caviar. Sturgeon production units commonly utilize commercial salmonid feeds, which contain large proportions of fish meal (FM) and fish oil (FO). Concerns regarding economics and sustainability have put pressure on aquafeed manufactures to efficiently utilize FM and FO, and to incorporate alternative protein sources, such as soybean meal (SBM). Therefore, the present studies estimated the optimal protein:energy ratio of juvenile Pallid Sturgeon Scaphirhynchus albus and evaluated the effects of increasing SBM composition on growth, feed efficiency, body and liver composition, and intestinal morphology of juvenile Shovelnose Sturgeon Scaphirhynchus platorhynchus, two species of Scaphirhynchus sturgeon of regional commercial importance. Protein:energy ratios were investigated using casein and dextrose based, semi-purified diets. Results indicated that Scaphirhynchus sturgeon are able to perform similarly across a wide range of protein:energy ratios (79 - 147 mg protein kcal-1), so long as adequate dietary energy (3,800 kcal kg-1 gross energy) is provided and essential amino acids are not limiting. Soybean meal was evaluated utilizing practical, isocaloric, isolipidic, isoenergetic test diets, designed to replace FM with increasing SBM. Juvenile Scaphirhynchus sturgeon were found to perform similarly on diets with up to 50% of FM replaced with SBM (336 g kg-1 diet). Evaluation of liver composition revealed that juvenile Shovelnose Sturgeon store less glycogen and crude lipid than other fish species, although no dietary differences were observed. Histological evaluation of the distal intestine revealed indications of SBM induced enteritis, though no statistical differences in measures were detected between treatments. This research is the first to describe optimal dietary formulation for the culture of Scaphirhynchus sturgeon.