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2019

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Animal Sciences

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Full-Text Articles in Life Sciences

The Vezo Communities And Fisheries Of The Coral Reef Ecosystem In The Bay Of Ranobe, Madagascar, Shane Abeare Dec 2019

The Vezo Communities And Fisheries Of The Coral Reef Ecosystem In The Bay Of Ranobe, Madagascar, Shane Abeare

University of New Orleans Theses and Dissertations

Madagascar, a country whose extraordinary levels of endemism and biodiversity are celebrated globally by scientists and laymen alike, yet historically has received surprisingly little research attention, is the setting of the present dissertation. Here, I contribute to the need for applied research by: 1) focusing on the most intensely fished section of the Toliara Barrier Reef, the Bay of Ranobe; 2) characterizing the marine environment, the human population, and the fisheries; and 3) collecting the longest known time-series of data on fisheries of Madagascar, thereby providing a useful baseline for future analyses. In Chapter 1, the bathymetry of the Bay …


The Potential For Dickeya Dianthicola To Be Vectored By Two Common Insect Pests Of Potatoes, Jonas K. Insinga Dec 2019

The Potential For Dickeya Dianthicola To Be Vectored By Two Common Insect Pests Of Potatoes, Jonas K. Insinga

Electronic Theses and Dissertations

Dickeya dianthicola (Samson) causing blackleg and soft rot was first detected in potatoes grown in Maine in 2014. Previous work has suggested that insects, particularly aphids, may be able to vector bacteria in this genus between plants, but no conclusive work has been done to confirm this theory. In order to determine whether insect-mediated transmission is likely to occur in potato fields, two model potato pests common in Maine were used: the Colorado potato beetle (Leptinotarsa decimlineata Say) and the green peach aphids (Myzus persicae Sulzer). Olfactometry and recruitment experiments evaluated if either insect discriminates between infected and …


The Effects Of Sediment Acidification And Temperature On The Immune Capacity Of The Atlantic Jackknife (Razor) Clam (Ensis Leei M. Huber, 2015), Brian Preziosi Dec 2019

The Effects Of Sediment Acidification And Temperature On The Immune Capacity Of The Atlantic Jackknife (Razor) Clam (Ensis Leei M. Huber, 2015), Brian Preziosi

Electronic Theses and Dissertations

Sediment acidification has been shown to negatively impact clams of economic importance such as the soft-shell clam, Mya arenaria Linnaeus, 1758, and hard clam, Mercenaria mercenaria (Linnaeus, 1758). Effects of sediment acidification on razor clams, including the Atlantic jackknife clam Ensis leei M. Huber, 2015, are unknown. E. leei has been identified as a species with potential for aquaculture operations on the New England coast. E. leei may be resilient to acidification and thus persist in acidified sediments where other clams cannot. To this end, the impact of acidified surface sediment on the internal immune capacity of adult (mean shell …


Feeding The Future Meat Doesn’T Come Cheap, Lukas C. Southard Dec 2019

Feeding The Future Meat Doesn’T Come Cheap, Lukas C. Southard

Capstones

Cultured – or as it is referred to by companies innovating the technology clean – meat is expected to be the next innovation to change the way the world gets its animal protein. Meat from animal cells grown in a lab seems like science fiction but it is around the corner from hitting your supermarket shelves. The technology has been developed but how these companies intend on scaling up their production to meet retail demands remains a mystery. So far companies have relied on seed and early stage investment from venture capital companies and private sources to fund research. Predictions …


Fish Passage And Hydropower: Investigating Resource Agency Decision-Making During The Ferc Hydropower Relicensing Process, Sarah Vogel Dec 2019

Fish Passage And Hydropower: Investigating Resource Agency Decision-Making During The Ferc Hydropower Relicensing Process, Sarah Vogel

Electronic Theses and Dissertations

Hydropower dams represent a significant challenge for the successful migration of sea-run fish, many species of which are in decline. Most hydropower dams in the United States are regulated by the Federal Energy Regulatory Commission (FERC), an independent federal agency responsible for granting 30 to 50-year licenses to projects for their continued operation. Licenses typically include conditions for the conservation of sea-run fish such as fish passage construction, operational changes, monitoring of effectiveness, and other mitigative conditions. While FERC remains the primary authority in licensing, the current regulatory framework stipulates input from other federal and state resource and regulatory agencies, …


Bone Mineral Density Of The Common Bottlenose Dolphin, Tursiops Truncatus: A Proposed Model For Monitoring Osteological And Ecosystem Health, James Wright Burrus Powell Dec 2019

Bone Mineral Density Of The Common Bottlenose Dolphin, Tursiops Truncatus: A Proposed Model For Monitoring Osteological And Ecosystem Health, James Wright Burrus Powell

Dissertations and Theses

Bone mineral density (BMD) in the pectoral flipper of the common bottlenose dolphin, Tursiops truncatus, was examined to address the need to define a comprehensive target site for clinical osteodensitometric assessment and to establish ranges of observed bone density values for this species. Radii were analyzed using dual energy X-ray absorptiometry (DXA), the accepted standard in human medical studies. Multiple loci within the radius were identified and assessed for their correlation to BMD of the entire bone. Radii BMD were also examined for differences based on sex, age, total body length, handedness, geographical affinity, and nutritional status at time …


Estimating Dry Matter Digestibility Of Forage In Equine Diets, Taylor N. Godwin Dec 2019

Estimating Dry Matter Digestibility Of Forage In Equine Diets, Taylor N. Godwin

MSU Graduate Theses

Previous research indicates equine fecal inoculates produce comparable results to cecal fluid when used for in vitro procedures to analyze dry matter digestibility (DMD). Equine hindgut microbial populations represented in fecal samples have been shown to be affected by diet. The objective of this study was to determine the effect of diet on in vitro DMD when fecal samples from horses on varying starch and fiber diets were used as inoculates. Six mature Quarter Horses (BW 522 ± 45kg) were used in a crossover repeated measures design to compare the effects of a grain vs. all forage diets on the …


Cyanobacterial Harmful Algal Bloom Ecology And Cyanotoxins In The Eutrophic Lake Winnebago-Green Bay Water System, Sarah L. Bartlett Dec 2019

Cyanobacterial Harmful Algal Bloom Ecology And Cyanotoxins In The Eutrophic Lake Winnebago-Green Bay Water System, Sarah L. Bartlett

Theses and Dissertations

Cyanobacterial harmful algal blooms (cyanoHABs) are frequently observed in water bodies used for recreation and drinking water production and can be detrimental to humans, animals, and general water quality. CyanoHABs are natural occurrences, but human activities such as agriculture, land use change, and runoff from urban and rural landscapes can promote and accelerate their expansion. The blooms are aesthetically unpleasing scums and can be laden with toxins (cyanotoxins) and toxic or otherwise bioactive peptides (TBPs) that can be harmful to humans and animals. Despite the vast research on cyanoHABs, cyanotoxin and TBP diversity and dynamics within a water column are …


A Landscape-Scaled And Community Ecology Approach To Wildlife Corridor Design In South Texas, James A. Stilley Dec 2019

A Landscape-Scaled And Community Ecology Approach To Wildlife Corridor Design In South Texas, James A. Stilley

Theses and Dissertations

A formidable challenge in landscape ecology is developing a sound resolution to mitigate the impacts of habitat fragmentation and restore connectivity to a degraded landscape. The problem is worldwide landscapes are becoming primarily anthropogenic and areas set aside for wildlife are small and isolated. Researchers’ have developed the concept of the wildlife corridor to mediate this situation but a proper methodology to implement this concept is still in its infancy. This study aims to uncover a quantitative and repeatable wildlife corridor design methodology based on the least cost analysis strategy with both a singular focal taxa approach and a comprehensive …


Investigating Egg Storage Conditions, Hatch Characteristics, And Feeding Methods Of Commercially Produced Poultry, Joshua R. Deines Dec 2019

Investigating Egg Storage Conditions, Hatch Characteristics, And Feeding Methods Of Commercially Produced Poultry, Joshua R. Deines

Graduate Theses and Dissertations

Advancements in poultry research continue to add knowledge and understanding to an already technical industry. Such information has led to new developments in early feeding strategies which provide nutrients to broiler chicks while in the egg or during transport. This wealth of knowledge in poultry research extends beyond chickens and is utilized for other species, such as quail and pheasants, including how fertile eggs are stored and incubated. However, methods of early feeding broilers have not been investigated in industry relevant approaches to understand its effects, including how timing of feed access interacts with the hatch window. As well, quail …


The Effects Of Foot And Udder Scoring On Cow And Calf Performance, Clayton Lee Mcguire Dec 2019

The Effects Of Foot And Udder Scoring On Cow And Calf Performance, Clayton Lee Mcguire

Graduate Theses and Dissertations

Foot soundness and udder conformation are essential for longevity in beef cattle. The objective of this study was to investigate the effects of foot angle (FA), claw set (CS), teat size (TS) and udder suspension (US) scores on cowherd performance. Data were analyzed for 1,685 observations on Angus-based cows over a four-year period. At weaning FA, CS, TS, and US were evaluated. Scores are based on nine-point scales. A score of one indicates straight pasterns, divergent toes, enlarged bottle shaped teats, and absence of a median suspensory ligament; nine indicates weak pasterns, curled toes, small symmetrical teats, and a tight …


Ecology And Conservation Of Shrubland Bird Communities In The Eastern Ghats Of Indi, Anant Deshwal Dec 2019

Ecology And Conservation Of Shrubland Bird Communities In The Eastern Ghats Of Indi, Anant Deshwal

Graduate Theses and Dissertations

Anthropogenic disturbance, in its multiple facets represents a major threat to biodiversity and habitat quality. Consequently, extensive research is guided towards understanding anthropogenic disturbance and their effects on wildlife for development of wildlife management plans. However, for development of effective wildlife management plans it is imperative that we understand the habitat use and preference by local fauna along with effects of anthropogenic presence. In this dissertation, I studied the habitat usage and preferences of Shrubland birds in the Eastern Ghats of India during the pre-monsoon and post monsoon seasons. Eastern Ghats show a marked difference from pre-monsoon season to post-monsoon …


Methods To Evaluate Ruminant Animal Production Responses, Jose Manuel Diaz Gomez Dec 2019

Methods To Evaluate Ruminant Animal Production Responses, Jose Manuel Diaz Gomez

Graduate Theses and Dissertations

In experiment 1, 80 steers (197.0 kg initial body weight; BW for fall, 116.9 kg for spring), were stocked at 2.45 and 4.1 calves/ha in fall and spring, respectively in 16 tall fescue pastures [fall ergovaline (EV) = 1,475 ppb and spring EV = 1,173 ppb] under 2 treatments, mineral (MIN) (n = 8) and cumulative management (CM) (n = 8). Forage allowance did not differ (P = 0.76) between CM and MIN during fall but differed during spring (P ≤ 0.05, 2.55 vs. 3.22 kg DM/kg BW, for MIN and CM, respectively). For fall, average daily gain (ADG) resulted …


Effects Of Dietary Copper, Zinc And Manganese Source And Level On The Acute Inflammatory Response Of Broilers, Chelsea Ellington Dec 2019

Effects Of Dietary Copper, Zinc And Manganese Source And Level On The Acute Inflammatory Response Of Broilers, Chelsea Ellington

Graduate Theses and Dissertations

Trace minerals, particularly copper, zinc and manganese, play a role in ensuring optimal immune function. To examine the effects of diets containing different levels and sources of trace minerals on the inflammatory response, Cobb 500 broilers were fed four experimental diets containing 5 mg/kg Cu and 45 mg/kg of Zn and Mn or 10 mg/kg Cu and 90 mg/kg Zn and Mn in either the sulfate or hydroxychloride form. When the broilers were 5 weeks of age, 16 μg of lipopolysaccharide (LPS) was injected into the pulp of growing feathers (GF; 16 GF per chicken; 1 μg LPS per GF). …


Estimation Of Genetic Components Related To Infectious Bovine Keratoconjunctivitis Susceptibility In Angus And Angus Derived Cattle Produced In The Southern United States, Eric Oxford Dec 2019

Estimation Of Genetic Components Related To Infectious Bovine Keratoconjunctivitis Susceptibility In Angus And Angus Derived Cattle Produced In The Southern United States, Eric Oxford

Graduate Theses and Dissertations

The economic impact of infectious bovine keratoconjunctivitis (IBK) has been documented in many parts of the world. Many researchers have observed that prevention of this disease is very difficult given current methodologies. This is primarily due to the multifactorial nature of this disease. The objective of this dissertation was to determine the impact of IBK on calf performance and estimate genetic parameters, heritability and estimated breeding values for IBK susceptibility. Data were analyzed using PROC GLIMMIX of SAS; while genetic parameters were estimated using a linear animal model for both single- and two-traits through MTDFREML. Additional evaluations calculated heritability using …


Effects Of 50:50 Proportion Bull:Cow Blend Levels And Incorporation Of Finely Textured Beef On The Color Of Precooked Ground Beef Patties, Colton Allen Althaber Dec 2019

Effects Of 50:50 Proportion Bull:Cow Blend Levels And Incorporation Of Finely Textured Beef On The Color Of Precooked Ground Beef Patties, Colton Allen Althaber

Graduate Theses and Dissertations

Variation in internal cooked color of ground beef is an economic concern for the ground beef market. Persistent pink color in hamburger patties can lead consumers to the perception of an undercooked product. Therefore, the objective of this study was to characterize the effects of bull:cow blend proportions, with or without finely textured beef (FTB), and cookery method on internal color of precooked ground beef patties. Batches (9.1 kg) of 85% lean ground beef were manufactured with 0, 33, 67, or 100% 50:50 bull:cow blend (remainder of lean was 100, 67, 33, or 0% Select-grade knuckles, respectively) mixed with 2 …


Eastern Collared Lizard (Crotaphytus Collaris) Population Declines In Ozark Landscapes: An Assessment Of Environmental Constraints., Casey L. Brewster Dec 2019

Eastern Collared Lizard (Crotaphytus Collaris) Population Declines In Ozark Landscapes: An Assessment Of Environmental Constraints., Casey L. Brewster

Graduate Theses and Dissertations

The Eastern Collared Lizard (Crotaphytus collaris) has experienced extensive population declines over the past half century in the Ozark Mountains. Previous research suggests that glade habitat degradation through woody vegetation encroachment is an important factor resulting in population declines. In this dissertation I used information on time-energy budgets to investigate the link between habitat degradation and shifts in life history traits likely resulting in population declines of Eastern Collared Lizards (Crotaphytus collaris) in the Ozarks. In chapter one, I addressed the influence of dense woody vegetation encroachment on age-specific growth, body size, body condition and reproduction of C. collaris in …


Investigating Growth Performance And Intestinal Barrier Integrity In Heat-Stressed Modern Broilers And Their Ancestor Jungle Fowl, Travis Tabler Dec 2019

Investigating Growth Performance And Intestinal Barrier Integrity In Heat-Stressed Modern Broilers And Their Ancestor Jungle Fowl, Travis Tabler

Graduate Theses and Dissertations

Heat stress (HS) has a negative effect on poultry production sustainability due to its adverse consequence on bird welfare, health, growth, and mortality. Although modern broilers have greater gut mass and higher energy use efficiency than unselected birds, they are more vulnerable to HS that induces “leaky gut syndrome,” or increased intestinal permeability. The aim of the current study was to determine the effect of HS on growth performance and gut barrier integrity in three modern broiler lines and their ancestor the Jungle Fowl. Four chicken populations including Giant Jungle Fowl (JF), Athens Canadian Random Bred (ACRB), 1995 Arkansas Random …


Getting Over The Dam: Overcoming Institutional Barriers To The Recovery Of Atlantic Salmon By Navigating The Social-Science/Policy Interface, Melissa E. Flye Dec 2019

Getting Over The Dam: Overcoming Institutional Barriers To The Recovery Of Atlantic Salmon By Navigating The Social-Science/Policy Interface, Melissa E. Flye

Electronic Theses and Dissertations

The term governance has undergone somewhat of an evolution since its inception, originally describing the act of governing, it has come to represent a more collaborative form of governing which is distinct from hierarchical control models (Marin and Mayntz, 1991). Collaborative governance refers to the systems associated with public policy decision making and resource management which span the jurisdictional boundaries of public agencies, levels of government, and/or public and private spheres in order to pursue a public policy goal or outcome (Emerson et al., 2012). Environmental management is often considered an inherently collaborative effort, as ecological systems and species rarely …


Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding Dec 2019

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in …


Coccidiosis Vaccination And Nutrient Utilization In Broiler Chickens, Alyson Elaine Gautier Dec 2019

Coccidiosis Vaccination And Nutrient Utilization In Broiler Chickens, Alyson Elaine Gautier

Graduate Theses and Dissertations

Four experiments were conducted to evaluate the interrelationships among coccidiosis vaccination and nutrient utilization in floor-reared broiler chickens. Experiment 1 longitudinally compared the effects of coccidiosis vaccination and a chemical coccidiostat on broiler performance, nutrient digestibility, and intestinal morphology. Coccidiosis vaccination had no significant impact on morphology, overall body weight gain and feed intake of vaccinated birds, although vaccination impaired overall FCR. Vaccination elicited a transient reduction in digestibility of energy and nutrients, particularly for lipids, but vaccinated birds were able to recover from these reductions by 20 d. Experiment 2 assessed the impact of vaccination in digestibility of different …


Strategies To Improve Forage Utilization By Sheep Offered Forage Mixtures, Valens Niyigena Dec 2019

Strategies To Improve Forage Utilization By Sheep Offered Forage Mixtures, Valens Niyigena

Graduate Theses and Dissertations

In the first experiment, alfalfa and novel endophyte-infected tall fescue (NE+) forages were harvested after a killing frost, then mixed to formulate 4 different treatments; alfalfa alone, 67% alfalfa +33% fescue, 33% alfalfa + 67% fescue, or 100% fescue. After 3 months of storage as silage, Dorper ewe lambs (n = 20; mean BW = 34.7 ± 6.65 kg) were fed silage for ad libitum consumption, using 5 animals per treatment. Increasing the proportion of NE+ tall fescue improved (P < 0.05) silage total acids and lactic acid concentrations and decreased silage ammonia concentration. Digestible dry matter and organic matter intake and nitrogen utilization parameters decreased with increasing inclusion of NE+ in diet. In the second experiment, 16 Dorper ewe lambs (41.8 ± 4.61 kg BW) were assigned to 4 different treatments; alfalfa silage alone (0 g/kg; CONT) or alfalfa silage mixed with chopped sericea lespedeza (SL) hay to provide 90 (LOW), 180 (MED), or 270 g/kg SL (HIGH) on a dry matter basis in a randomized complete block design experiment with 2 period to provide 4 observations per treatment for each experimental period. Increasing the proportion of sericea lespedeza in the diet decreased dry matter and organic matter digestibility but did not affect feed intake. Fecal nitrogen (g/kg N intake) increased linearly (P < 0.01) while urinary N (g/ day and g/ kg of N intake) tended to decreased linearly and quadratically (P ≤ 0.1) with increasing the proportion of SL in diet. In the third experiments, 16 gestating Dorper ewe lambs (49.1 ± 4.61 kg BW) were allocated to 4 treatments; alfalfa silage alone (0% g/kg; CONT) or alfalfa silage mixed with lablab purpureus(LP) hay to provide 90 (LOW), 180 (MED), or 270 g/kg LP (HIGH) on a dry matter (DM) basis, in a randomized complete block design experiment with a total 8 replication per treatment. Supplementation of LP in diet increased quadratically (P ≤ 0.04) forage dry matter, organic matter intake, digestible dry matter and digestible organic matter intake (P < 0.05). Nitrogen apparently absorbed and urinary N both decreased linearly (P < 0.01) with adding more LP hay in diet. Harvesting and mixing alfalfa and fescue after a killing frost improved silage fermentation characteristics and supplementation of tannins from SL and polyphenol from LP altered N excretion.

Key words: lablab, sericea lespedeza, alfalfa silage, nitrogen, sheep.


Evaluation Of A Proprietary Slow-Release Oxytocin Therapy And Return Of The Luteolytic Mechanism In Mares, Brendan Andrew Sarnecky Dec 2019

Evaluation Of A Proprietary Slow-Release Oxytocin Therapy And Return Of The Luteolytic Mechanism In Mares, Brendan Andrew Sarnecky

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Prolonging function of the corpus luteum (CL) is a method of suppressing estrus that maintains secretion of endogenous progesterone to keep mares out of heat naturally. The use of oxytocin to prolong CL function is becoming more popular. In these therapies, upregulation of cyclooxygenase-2 is inhibited, which impairs prostaglandin F2α ( PGF2α) production. Intramuscular (IM) administration of 60 IU of oxytocin once daily from 7 to 14 days after ovulation is currently the most common treatment protocol. Although that protocol is efficacious in ≥70% of treated mares, the need for daily administration is a drawback to its use. A proprietary …


The Impact Of Ergot Alkaloid Consumption During Gestation On Maternal Performance And Fetoplacental Development, Jessica Lynn Britt Dec 2019

The Impact Of Ergot Alkaloid Consumption During Gestation On Maternal Performance And Fetoplacental Development, Jessica Lynn Britt

All Dissertations

Tall fescue is the primary cool season perennial forage grass in southeastern US for grazing livestock. Tall fescue the is known to be drought tolerant , disease resistant, grazing tolerant and overall very hardy. Many of these attributes common to fescue are due to a symbiotic relationship between the fescue plant and an endophyte, Epichloë coenophiala , which produces a class of mycotoxins known as ergot alkaloids. These ergot alkaloids are similar in structure to several biogenic amines, such as epinephrine, norepinephrine, and dopamine. When consumed, ergot alkaloids cause a syndrome known as fescue toxicosis which causes problems with weight …


The Effects Of Seasonal Variations, El Niño-Southern Oscillation, And Climate Change On The Tuna-Dolphin Association, Caitlynn Birch, Michael D. Scott, Zhi-Yong Yin, Lisa T. Ballance Nov 2019

The Effects Of Seasonal Variations, El Niño-Southern Oscillation, And Climate Change On The Tuna-Dolphin Association, Caitlynn Birch, Michael D. Scott, Zhi-Yong Yin, Lisa T. Ballance

Theses

Tuna and dolphins swim together in the waters of the eastern tropical Pacific, and this association has long benefitted tuna fishermen and intrigued scientists. Although the tuna-dolphin association is often referred to as a “mystery,” much is known about the association. Yellowfin tuna are primarily caught with spotted dolphins and, to a lesser extent, spinner dolphins; historically the spotted dolphin has borne the brunt of the bycatch mortality. The tuna-dolphin association is thought to be a product of the distinct oceanography of the ETP: a shallow mixed layer, a thick oxygen minimum zone, and warm surface waters. As the mixed …


Molecular Survey Of Helminths Infecting Ground Dwelling Birds In The Grouse Subfamily Tetraoninae, Briana M. Sesmundo Nov 2019

Molecular Survey Of Helminths Infecting Ground Dwelling Birds In The Grouse Subfamily Tetraoninae, Briana M. Sesmundo

Honors College Theses

Alaskan grouse and ptarmigan (Galliformes) are important avian game species in Alaska. Interestingly, gallids harbor a fairly diverse helminth fauna, particularly cestodes, which may make birds with high parasite loads more susceptible to predation. Unfortunately, there is limited information available on the helminth fauna of Alaskan gallids, and no molecular surveys. The present study aims to develop baseline data on diversity of intestinal and subcutaneous (filariid) helminth infections in galliforms using morphological and molecular (DNA) approaches. These data can then be used to better understand changes in helminth community structure given current environmental volatility. The intestines, cloaca, liver and kidneys …


Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey Gadek Nov 2019

Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey Gadek

Biology ETDs

The distribution of life across the Andes mountains reflects historical elevational-range contraction and expansion. Whereas contraction implies specialization, expansion requires overcoming hidden barriers. Three eco-evolutionary phenomena may drive patterns in rates of elevational range evolution: (1) The Dobzhansky-MacArthur Phenomenon (DMP) predicts lower rates of upward expansion with harsher physical conditions, while downward expansion increases with lower diversity; (2) the evolutionary tendency toward specialization predicts contraction increases when ranges are broad; and (3) natural selection for respiratory performance could suppress expansion across mid-elevations due to gene-environment mismatch. We modeled elevational range shifts of Neotropical landbirds. Contrary to the DMP, upward expansion …


Habitat Associations And Reproduction Of Fishes On The Northwestern Gulf Of Mexico Shelf Edge, Elizabeth Marie Keller Nov 2019

Habitat Associations And Reproduction Of Fishes On The Northwestern Gulf Of Mexico Shelf Edge, Elizabeth Marie Keller

LSU Doctoral Dissertations

Several of the northwestern Gulf of Mexico (GOM) shelf-edge banks provide critical hard bottom habitat for coral and fish communities, supporting a wide diversity of ecologically and economically important species. These sites may be fish aggregation and spawning sites and provide important habitat for fish growth and reproduction. Already designated as habitat areas of particular concern, many of these banks are also under consideration for inclusion in the expansion of the Flower Garden Banks National Marine Sanctuary. This project aimed to gain a more comprehensive understanding of the communities and fish species on shelf-edge banks by way of gonad histology, …


Assessment Of Off-Bottom Oyster (Crassostrea Virginica) Aquaculture Techniques On Biofouling In The Northern Gulf Of Mexico, Ellis Chapman Nov 2019

Assessment Of Off-Bottom Oyster (Crassostrea Virginica) Aquaculture Techniques On Biofouling In The Northern Gulf Of Mexico, Ellis Chapman

LSU Master's Theses

Although off-bottom oyster aquaculture is a rising industry in the northern Gulf of Mexico, it is susceptible to biofouling, the accumulation of organisms on industry surfaces. Biofouling creates problems for commercial growers by increasing the costs of labor associated with biofouling management. The most used off-bottom production techniques involve aerial exposure. OysterGro™ 6-slot off-bottom oyster cages were used in this project to test aerial exposure frequency, antifouling coatings and bag position on mortality, growth rates, shell ratios and condition indices on four sites in the northern Gulf of Mexico. Aerial exposure of floating cages was performed in increments of once …


Immune Gene Diversity And Populations Structure Of Reticulated Flatwoods Salamander (Ambystoma Bishopi), Steven Tyler Williams Nov 2019

Immune Gene Diversity And Populations Structure Of Reticulated Flatwoods Salamander (Ambystoma Bishopi), Steven Tyler Williams

LSU Master's Theses

Reticulated flatwoods salamander (Ambystoma bishopi) populations began decreasing dramatically in the late 1900s. Contemporary populations are small, isolated, and may be susceptible to inbreeding and reduced adaptive potential because of low genetic variation. Genetic variation at immune genes is especially important as it influences disease susceptibility and adaptation to emerging infectious pathogens, a central conservation concern for declining amphibians. Connectivity between isolated populations is also vital to maintain genetic diversity and avoid inbreeding. I collected tissue samples from across the extant range of this salamander to examine genetic variation and population structure in: immune genes broadly (immunome), the …