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Progressive Decline Of Testicular Function In Leptinreceptor Deficient Obese Mice, Jennifer Long May 2015

Progressive Decline Of Testicular Function In Leptinreceptor Deficient Obese Mice, Jennifer Long

Masters Theses

The incidence of obesity and metabolic syndrome among the human population is increasing, but the effects on male fertility are unresolved. Leptin insensitivity appears to show a consistent relationship between obesity and fertility problems in men. Genetically modified mice lacking the leptin hormone (ob/ob) or leptin receptor (db/db) are reported to be subfertile and/or infertile but there is only minimal information about testicular function (sperm and hormone production) and the progression of infertility. Therefore, this study was designed to investigate testicular function using a leptin-receptor-deficient obese mouse model (the POUND mouse; Charles River). Testicular sperm production is reduced in POUND …


Effects Of Pre-Release Physical Stressors On Post-Release Success Of Hatchery-Reared Spotted Seatrout, Taylor Westbrook Guest May 2015

Effects Of Pre-Release Physical Stressors On Post-Release Success Of Hatchery-Reared Spotted Seatrout, Taylor Westbrook Guest

Master's Theses

Alteration of habitat associated with coastal development and increased demand for food and recreation can result in the depletion of fisheries resources such as the Spotted Seatrout (Cynoscion nebulosus), the Gulf of Mexico’s most popular recreational fish. Stock enhancement, or the release of cultured fish to supplement wild populations, is one potential tool for managing important fisheries resources. Although much effort has gone into marine stock enhancement, the effectiveness of stocking is not well established, and techniques for ensuring success have not been developed. Although the basic biology of the Spotted Seatrout is well known, comparatively little is known about …


Effect Of Aggregation At A Winter Feeding Station On Intestinal Parasite Load In Elk (Cervus Canadensis), Morgan Jaromilla Hughes May 2015

Effect Of Aggregation At A Winter Feeding Station On Intestinal Parasite Load In Elk (Cervus Canadensis), Morgan Jaromilla Hughes

Undergraduate Honors Capstone Projects

Winter feeding stations are used throughout the western US to reduce elk depredation of crops and haystacks on private lands. Many of the unintended effects of such artificial congregation remain unexamined, but generally, across species, locally increased host densities result in increased parasite loads. This adds physiological stress to individual animals and in game species such as elk it could reduce their value to sportsmen. Through laboratory analyses of fresh samples, we recorded nematode egg densities in elk feces collected during two periods ( early and late) in the supplementary feeding season. Mean nematode egg density remained fairly constant in …


Effects Of Beef Finishing Diets And Muscle Type On Meat Quality, Fatty Acids And Volatile Compounds, Arkopriya Chail May 2015

Effects Of Beef Finishing Diets And Muscle Type On Meat Quality, Fatty Acids And Volatile Compounds, Arkopriya Chail

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Consumer evaluation, proximate data, Warner-Bratzler shear force (WBSF), fatty acid (FA) composition and volatile compounds were analyzed from the ribeye steaks (LT) finished on conventional feedlot (FL) and forages, including a perennial legume, birdsfoot trefoil (BFT; Lotus corniculatus), and a grass, meadow brome (Bromus riparius Rehmann, Grass). Representative retail forage (USDA Certified Organic Grass-fed, COGF) and conventional beef (USDA Top Choice, TC) were investigated (n = 6) for LT. Additionally, the effects of diet on round (GM) and chuck (TB) muscles FL, BFT and Grass were explored. Forage-finished beef was less liked in most of the affected …


Improvement Of Nutrient Utilization Efficiency, Ruminal Fermentation And Lactational Performance Of Dairy Cows By Feeding Birdsfoot Trefoil, Rachael G. Christensen May 2015

Improvement Of Nutrient Utilization Efficiency, Ruminal Fermentation And Lactational Performance Of Dairy Cows By Feeding Birdsfoot Trefoil, Rachael G. Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Condensed tannins (CT) are compounds that have shown potential to reduce the environmental impact of dairy farming waste products. In two live animal studies and a continuous culture study, it was hypothesized that feeding birdsfoot trefoil (Lotus corniculatus, BFT), a CT-containing legume, would improve nutrient utilization, milk, and component yield of dairy cows compared with feeding alfalfa hay or grass pasture in two studies, while feeding BFT forage would decrease methane production and improve rumen fermentation in addition to concentrate supplementation was the hypothesis of the third study. Reduction in milk urea nitrogen (MUN) and …


Correlation Of Amyloid Beta And Spatial Learning And Memory Deficits On A Thy1-App Mouse Model For Alzheimer's Disease, Amber Lynn Betz May 2015

Correlation Of Amyloid Beta And Spatial Learning And Memory Deficits On A Thy1-App Mouse Model For Alzheimer's Disease, Amber Lynn Betz

Theses and Dissertations - UTB/UTPA

The McGill-Thy1 APP mouse is a triple transgenic model of Alzheimer disease, which has the mutant amyloid precursor protein to synergistically over-produce amyloid beta plaques. These mice exhibit visuo-spatial learning impairment at 3 months of age and memory impairment at 10-13 months of age in the Morris water maze. To extend these findings mice at 3, 5, and 7 months of age were tested on the Barnes maze. Non-Transgenic and Transgenic mice showed improvement during acquisition. However, 3 month and 5 month McGill Thy1- APP mice showed impaired acquisition learning while 7 month showed a learning and memory deficit compared …


Effects Of Crystalline Amino Acid Supplementation Of Reduced Crude Protein (Rcp) Diet On Net Energy Basis On Growing-Finishing Swine, Daniel Cook May 2015

Effects Of Crystalline Amino Acid Supplementation Of Reduced Crude Protein (Rcp) Diet On Net Energy Basis On Growing-Finishing Swine, Daniel Cook

Graduate Theses and Dissertations

Barrows and gilts (n=210) were used to test the effects of crystalline amino acid (AA) supplementation of reduced crude protein (RCP) diets formulated on a net energy basis on quality characteristics of the LM from growing-finishing pigs. Pigs were blocked by weight, and pens (3 barrows and 3 gilts/pen) within each block were assigned randomly to either corn-soybean meal diets (C) or 1 of 3 RCP diets and added crystalline AA levels for the dietary treatments during each feeding phase. During the last 3-wk feeding phase, 10 ppm of ractopamine were included in all diets. At slaughter and after a …


Block And Bridle Annual 2015 Apr 2015

Block And Bridle Annual 2015

Block and Bridle Annual (1933–2021)

Three objectives of the National Block and Bridle Club are to promote animal agriculture through the activities of the club, to supplement students’ study of the animal sciences, and to bring about a closer relationship among students who choose to be a part of the organization. I believe the Block and Bridle club at the University of Nebraska - Lincoln has been successful in accomplishing these goals over the past year and I sincerely thank all of the officers and members who have given their time and effort to make this possible. I am excited to say that our active …


Plant Driven Movement: Does Plant Quality Affect The Foraging Patterns Of Successful Male Sage-Grouse (Centrocercus Urophasianus)?, Karli Graski, Marcella R. Fremgen, Gail Patricelli, Alan Krakauer, Jennifer S. Forbey Apr 2015

Plant Driven Movement: Does Plant Quality Affect The Foraging Patterns Of Successful Male Sage-Grouse (Centrocercus Urophasianus)?, Karli Graski, Marcella R. Fremgen, Gail Patricelli, Alan Krakauer, Jennifer S. Forbey

College of Arts and Sciences Presentations

The structural and dietary quality of plants is highly variable across the landscape and may influence energy acquisition by herbivores needed for energy dependent activities. For sage-grouse, male display efforts are energetically expensive, with successful males expending up to four times their basal metabolic rate to display. Previous work found that males who had the greatest energy expenditure during the lekking season also lost the least weight and foraged farthest from the lek. We hypothesized that the energetic benefit of foraging farther from the lek is due to higher quality food or cover compared to near lek vegetation. To initially …


Is Habitat Use By Greater Sage-Grouse Proportional To Availability Of Plant Morphotypes?, Jacqueline Peña, Marcella Fremgen, John C. Connelly, Jennifer Forbey Apr 2015

Is Habitat Use By Greater Sage-Grouse Proportional To Availability Of Plant Morphotypes?, Jacqueline Peña, Marcella Fremgen, John C. Connelly, Jennifer Forbey

College of Arts and Sciences Presentations

Greater Sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) select sagebrush plants for food that are high in protein. However, sagebrush produce toxins called monoterpenes that can inhibit enzymatic reactions and interrupt cellular processes and therefore result in decreased intake by sage-grouse. Moreover, species, subspecies, populations, and morphotypes of sagebrush can vary in the concentration of toxins produced. Preliminary analysis has shown that different morphotypes of sagebrush have different chemical profiles, and this may influence selection at a scale below species. Our research aims to determine whether sage-grouse select specific morphotypes of sagebrush to maximize biomass consumed per bite or minimize …


Characteristics Of Trailer Thermal Environment During Commercial Swine Transport Managed Under U.S. Industry Guidelines, Y Xiong, Angela Green, Richard S. Gates Apr 2015

Characteristics Of Trailer Thermal Environment During Commercial Swine Transport Managed Under U.S. Industry Guidelines, Y Xiong, Angela Green, Richard S. Gates

Department of Animal Science: Faculty Publications

Transport is a critical factor in modern pork production and can seriously affect swine welfare. While previous research has explored thermal conditions during transport, the impact of extreme weather conditions on the trailer thermal environment under industry practices has not been well documented; and the critical factors impacting microclimate are not well understood. To assess the trailer microclimate during transport events, an instrumentation system was designed and installed at the central ceiling level, pig level and floor-level in each of six zones inside a commercial swine trailer. Transport environmental data from 34 monitoring trips (approximately 1–4 h in duration each) …


Isotopic Incorporation Rates And Discrimination Factors In Mantis Shrimp Crustaceans., Maya Devries, Carlos Del Rio, Tate Tunstall, Todd Dawson Apr 2015

Isotopic Incorporation Rates And Discrimination Factors In Mantis Shrimp Crustaceans., Maya Devries, Carlos Del Rio, Tate Tunstall, Todd Dawson

Faculty Publications, Biological Sciences

Stable isotope analysis has provided insights into the trophic ecology of a wide diversity of animals. Knowledge about isotopic incorporation rates and isotopic discrimination between the consumer and its diet for different tissue types is essential for interpreting stable isotope data, but these parameters remain understudied in many animal taxa and particularly in aquatic invertebrates. We performed a 292-day diet shift experiment on 92 individuals of the predatory mantis shrimp, Neogonodactylus bredini, to quantify carbon and nitrogen incorporation rates and isotope discrimination factors in muscle and hemolymph tissues. Average isotopic discrimination factors between mantis shrimp muscle and the new diet …


Sphingolipids Are Required For Efficient Triacylglycerol Loss In Conjugated Linoleic Acid Treated Adipocytes, Wei Wang, Michael E. Fromm Apr 2015

Sphingolipids Are Required For Efficient Triacylglycerol Loss In Conjugated Linoleic Acid Treated Adipocytes, Wei Wang, Michael E. Fromm

Department of Animal Science: Faculty Publications

Conjugated linoleic acid (CLA) reduces adiposity in human and mouse adipocytes. This outcome is achieved through a variety of biological responses including increased energy expenditure and fatty acid oxidation, increased inflammation, repression of fatty acid biosynthesis, attenuated glucose transport, and apoptosis. In the current study, profiling of 261 metabolites was conducted to gain new insights into the biological pathways responding to CLA in 3T3-L1 adipocytes. Sphinganine and sphingosine levels were observed to be highly elevated in CLA treated adipocytes. Exogenous chemicals that increased endogenous ceramide levels decreased lipid levels in adipocytes, and activated AMP-activated protein kinase (AMPK) as well as …


Wpa News 96 (2015), World Pheasant Association Apr 2015

Wpa News 96 (2015), World Pheasant Association

Galliformes Specialist Group and Affiliated Societies: Newsletters

WPA News (Spring 2015), number 96

Published by the World Pheasant Association


Tracking The Elephant (Lexodonta Africana) Corridor And The Human-Wildlife Conflict In Selela Village, Nicole Chlebek, Laura Stalter Apr 2015

Tracking The Elephant (Lexodonta Africana) Corridor And The Human-Wildlife Conflict In Selela Village, Nicole Chlebek, Laura Stalter

Independent Study Project (ISP) Collection

The beastly journey of long-distance migration for the African Elephant (Lexodonta Africana) is important for upholding their connections between diminishing protected areas, especially in northeastern Tanzania. However, human development is encroaching into these corridors, creating a human-elephant conflict, which can ruin livelihoods of villagers, depending on the extent of conflict. This study focused on exploring the hypothesized human-elephant conflict on the Selela corridor, specifically in Selela village, as well as GPS (Global Positioning System) mapping evidence of elephant travel along the projected Selela elephant corridor connecting Ngorongoro Conservation Area (NCA), to Selela Forest Reserve (SFR), and finally to Manyara Ranch. …


Identification Of Meat Species In Pet Foods Using A Real-Time Polymerase Chain Reaction (Pcr) Assay, Tara A. Okuma, Rosalee S. Hellberg Apr 2015

Identification Of Meat Species In Pet Foods Using A Real-Time Polymerase Chain Reaction (Pcr) Assay, Tara A. Okuma, Rosalee S. Hellberg

Food Science Faculty Articles and Research

Product mislabeling, adulteration, and substitution are increasing concerns in highly processed foods, including pet foods. Although regulations exist for pet foods, there is currently a lack of information on the prevalence of pet food mislabeling. The objective of this study was to perform a market survey of pet foods and pet treats marketed for domestic canines and felines to identify meat species present as well as any instances of mislabeling. Fifty-two commercial products were collected from online and retail sources. DNA was extracted from each product in duplicate and tested for the presence of eight meat species (bovine, caprine, ovine, …


Investigation Of Dried Distillers Grains With Solubles (Ddgs) Susceptibility To Red Flour Beetle (Tribolium Castaneum (Herbst)) Infestation, Mahsa Fardisi Apr 2015

Investigation Of Dried Distillers Grains With Solubles (Ddgs) Susceptibility To Red Flour Beetle (Tribolium Castaneum (Herbst)) Infestation, Mahsa Fardisi

Open Access Dissertations

Protecting livestock feed from insect infestation is a common challenge that feed facility managers and farmers have to deal with. It becomes an issue of importance because insect infestation degrades feed quality and quantity. Dried Distillers Grains with Solubles (DDGS) is added to livestock feed because of its high protein content. As DDGS usage in animal feed increases, understanding the susceptibility of DDGS, when mixed with livestock feed, to insect infestation is necessary for safe feed storage. This research addressed four questions. The first looked at the susceptibility of DDGS, when stored as a raw ingredient, to Tribolium castaneum (Herbst) …


Propionate Induces Gluconeogenesis In Dairy Cattle Through Direct Activation Of The Bovine Cytosolic Phosphoenolpyruvate Carboxykinase Gene Promoter, Qian Zhang Apr 2015

Propionate Induces Gluconeogenesis In Dairy Cattle Through Direct Activation Of The Bovine Cytosolic Phosphoenolpyruvate Carboxykinase Gene Promoter, Qian Zhang

Open Access Dissertations

Phosphoenolpyruvate carboxykinase (PCK, GTP; EC4.1.1.32) catalyzes the conversion of oxaloacetate (OAA) to phosphoenolpyruvate (PEP), a critical reaction for gluconeogenesis. The two isoforms of PCK, namely cytosolic PCK (PCK1), and the mitochondrial PCK (PCK2) are abundantly expressed in liver and kidney. Increased PCK1 activity and mRNA expression in liver is observed as feed intake recovers during early lactation in dairy cows, a condition linked to increased ruminal propionate production. The central hypothesis of this dissertation is that propionate regulates its own metabolism in liver of dairy cattle through regulation of the PCK1 gene. The objectives of this dissertation were to determine: …


Evaluation Of Nutritional Traits Of Soy Protein Concentrate (Spc) In Broiler Chicks And Turkey Poults, Noorjan Zazai Apr 2015

Evaluation Of Nutritional Traits Of Soy Protein Concentrate (Spc) In Broiler Chicks And Turkey Poults, Noorjan Zazai

Open Access Theses

The objectives of this study were to determine the apparent metabolizable energy (AME), nitrogen corrected AME (AMEn) of soy protein concentrate (SPC), and standardized ileal amino acid digestibility (SIAAD) of (SPC) and dehulled soybean meal (SBM) in broiler and turkey poults. Soy protein concentrate and SBM was the only source of CP in their respective semi-purified diets used for estimating SIAAD in 7 and 21 d-old broiler chicken and turkey poults. Two experiments (Exp 1 and 2) were conducted with 6 replicate cages of 20 (d 7) and 6 (d 21) birds/cage. In Exp.1, experimental diets containing 0, …


Growing South Dakota (Spring 2015), College Of Agriculture &. Biological Sciences Apr 2015

Growing South Dakota (Spring 2015), College Of Agriculture &. Biological Sciences

Growing South Dakota (Publication of the College of Agriculture, Food and Environmental Sciences)

This issue includes the 2014 SDSU Extension Annual Report.

[Page] 2 Committed To South Dakotans: Programs Focus On “Healthy Food, Healthy Families, Healthy Communities”
[Page] 4 Serving South Dakota’s Multi-Cultural Communities: Programs Take Root In Sioux Falls And On Standing Rock Indian Reservation
[Page] 4 Relevant Resource: New Manual Provides Guidance For Farmers Markets
[Page] 6 Food Growers Unite: Formation Of “Food Hub” Being Explored
[Page] 8 Envisioning The Future: Extension Assists Community Leaders With Forward Thinking
[Page] 10 Innovative New Tools: Online Resources Provide Useful Climate Data, Drainage Calculators
[Page] 12 Meeting Producer Needs: Production Knowledge Enhanced With Extension …


Ecological Studies Of Wolves On Isle Royale, 2014-2015, John A. Vucetich, Rolf O. Peterson Mar 2015

Ecological Studies Of Wolves On Isle Royale, 2014-2015, John A. Vucetich, Rolf O. Peterson

Ecological Studies of Wolves on Isle Royale

Annual Report 2014-2015


Ocean Food Systems, Barry A. Costa-Pierce Mar 2015

Ocean Food Systems, Barry A. Costa-Pierce

Marine Sciences Faculty Presentations

Presentation given during session on Food Justice, where Barton Seaver, Director of the Healthy and Sustainable Food Program in the T.H. Chan School of Public Health at Harvard, described a great nutrition and health crisis in America perpetuated by groups demarketing seafood and promoting meat in the American diet. Seaver noted that Americans consume about 167 lbs. of meat a year and only 14 lbs. of seafood, leading to connected public health and environmental crises, heart disease, and obesity.

According to presenter Barry Costa-Pierce:

Seafood systems in the USA are our most insane foods; America imports nearly every seafood we …


Integrating Experiential Learning Into Animal Science Curriculum Through A Hands-On Beef Cattle Management And Marketing Contest, Corinne J. Harrison Mar 2015

Integrating Experiential Learning Into Animal Science Curriculum Through A Hands-On Beef Cattle Management And Marketing Contest, Corinne J. Harrison

Theses and Dissertations

According to the Illinois Agricultural Education, nearly 61% of students beginning their undergraduate studies in Agriculture at a 2-year college in Illinois come from non-farm backgrounds. Yet, knowledge of and experience in livestock operations is still a requirement for many careers in the animal science industry. In response to this predicament, the Department of Agriculture at Illinois State University has implemented a course that provides students an opportunity to gain hands-on experience with beef cattle management and marketing. The course was designed to enhance learning by requiring students to develop and execute a management and marketing plan for a pen …


Applying Gps And Accelerometers To The Study Of African Savanna (Loxodonta Africana) And Asian Elephant (Elephas Maximus) Welfare In Zoos, Matthew Robert Holdgate Mar 2015

Applying Gps And Accelerometers To The Study Of African Savanna (Loxodonta Africana) And Asian Elephant (Elephas Maximus) Welfare In Zoos, Matthew Robert Holdgate

Dissertations and Theses

African savanna elephants (Loxodonta africana) and Asian elephants (Elephas maximus) are a focus of welfare research in zoos due to their high intelligence, complex social structure, and sheer size. Due to these challenges, some argue that zoos are inherently incapable of providing appropriate care for elephants, while others believe that zoos can fulfill the needs of these species with improved husbandry. There is a general consensus from both within and outside of zoos, however, that zoos must improve their elephant programs or cease exhibiting these animals altogether. Now more than ever, applied research on zoo elephant welfare is needed to …


Shifts In Attack Behavior Of An Important Kelp Forest Predator Within Marine Reserves, J. S. Berriman, M. C. Kay, D. C. Reed, A. Rassweiler, D. A. Goldstein, William G. Wright Mar 2015

Shifts In Attack Behavior Of An Important Kelp Forest Predator Within Marine Reserves, J. S. Berriman, M. C. Kay, D. C. Reed, A. Rassweiler, D. A. Goldstein, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Marine reserves have become increasingly valuable tools with which to manage ecosystems. These reserves consistently restore populations of top predators, often reducing availability of their favored prey. We hypothesized that such prey reduction in reserves causes protected predators to alter their attack behavior to include less palatable prey, potentially amplifying top-down effects on community structure. To test this hypothesis, we presented the relatively unpalatable sea hare Aplysia californica to freely foraging spiny lobsters Panulirus interruptus in 4 marine no-take reserves, each paired with an adjacent fished area. We found that lobsters only attacked sea hares inside reserves, where lobster density …


Tallgrass Prairie Vegetation Response To Spring Fires And Bison Grazing, Stephen L. Winter, Brady W. Allred, Karen R. Hickman, Samuel D. Fuhlendorf Mar 2015

Tallgrass Prairie Vegetation Response To Spring Fires And Bison Grazing, Stephen L. Winter, Brady W. Allred, Karen R. Hickman, Samuel D. Fuhlendorf

School of Natural Resources: Faculty Publications

Spring fires in tallgrass prairie can create environmental conditions conducive to plant growth in the subsequent growing season. Following fires, burned areas can also be attractive to grazing animals such as bison (Bison bison). Sustained grazing activity within recently burned areas can alter vegetation structure relative to nearby landscape patches that haven’t burned recently. In 2007, we collected data on bison grazing activity, vegetation structure, and the growth and reproduction of a perennial forb, Arnoglossum plantagineum, in Oklahoma tallgrass prairie. We compared these variables in landscape patches that had burned in the spring of 2007 to measurements …


Temporal Patterns Of Nutrition Dependence In Secondary Sexual Traits And Their Varying Impacts On Male Mating Success, Malcolm F. Rosenthal, Eileen A. Hebets Mar 2015

Temporal Patterns Of Nutrition Dependence In Secondary Sexual Traits And Their Varying Impacts On Male Mating Success, Malcolm F. Rosenthal, Eileen A. Hebets

Eileen Hebets Publications

Variation in the quantity of nutrients ingested over an individual’s lifetime is likely to differentially affect distinct male secondary sexual traits and courtship signals, potentially providing females with information about a male’s past and present foraging history. We hypothesize that female choice is thus influenced by a male’s lifetime foraging history. To test this, we manipulated the quantity of nutrients (i.e. prey items) available to male wolf spiders, Schizocosa stridulans, using a fully crossed 2 × 2 design with low versus high prey quantity across juvenile and adult life stages, and assessed the impact of these diet treatments on male …


News Of The Department Of Animal Science, Department Of Animal Science Feb 2015

News Of The Department Of Animal Science, Department Of Animal Science

Animal Science Newsletters

No abstract provided.


Repercussions Of Growth Path On Carcass Characteristics, Meat Colour And Shear Force In Alentejana Bulls, P Costa, J A. Simoes, A S.H. Costa, J P.C. Lemos, D Navas, J F. Hocquette, C R. Calkins, R J.B. Bessa Feb 2015

Repercussions Of Growth Path On Carcass Characteristics, Meat Colour And Shear Force In Alentejana Bulls, P Costa, J A. Simoes, A S.H. Costa, J P.C. Lemos, D Navas, J F. Hocquette, C R. Calkins, R J.B. Bessa

Department of Animal Science: Faculty Publications

The aim of this study was to evaluate the carcass and meat characteristics of eight muscles from bulls with distinct growth paths. A total of 40 Alentejana male calves were allocated to two distinct feeding regimes. In the continuous growth (CG) system, the animals were fed concentrates plus hay and were slaughtered at 18 months of age. On the other hand, in the discontinuous growth (DG) system, the animals were fed hay until 15 months of age; the cattle were then fed the same diet provided to the CG group from 15 to 24 months of age. The DG reduced …


Ectoparasitism Shortens The Breeding Season In A Colonial Bird, Charles R. Brown, Mary Bomberger Brown Feb 2015

Ectoparasitism Shortens The Breeding Season In A Colonial Bird, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

When blood-feeding parasites increase seasonally, their deleterious effects may prevent some host species, especially those living in large groups where parasites are numerous, from reproducing later in the summer. Yet the role of parasites in regulating the length of a host’s breeding season—and thus the host’s opportunity for multiple brooding—has not been systematically investigated. The highly colonial cliff swallow (Petrochelidon pyrrhonota), a temperate-latitude migratory songbird in the western Great Plains, USA, typically has a relatively short (eight to nine week) breeding season, with birds rarely nesting late in the summer. Colonies at which ectoparasitic swallow bugs (Oeciacus vicarius) were experimentally …