Veterinary Pathology and Pathobiology Commons^™

Infection Potential Of Rickettsia Felis Via Ingestion, Matthew M. Schexnayder

LSU Master's Theses

Rickettsia felis is the etiologic agent of flea-borne spotted fever (FBSF) in humans and a poorly described cause of fever in animals. It is transmitted by its primary arthropod vector and reservoir host, the cat flea Ctenocephalides felis. Known routes of Rickettsia felis transmission between Rickettsia felis-infected cat fleas and vertebrate hosts include cutaneous bites and contamination of cutaneous wounds with infective flea feces. The bulk of FBSF infections occur in young children in Africa, though infections of people at all ages all over the world have been confirmed. As mammals and young children frequently come into contact …

Outer Surface Lipoprotein Layer Homeostasis And Gene Regulation In Borrelia Burgdorferi, Poonam Dadhwal

LSU Doctoral Dissertations

The outer surface lipoprotein (osp) layer forms an interface between the internal and the external environment of the Lyme disease spirochete, Borrelia burgdorferi. The homeostatic maintenance of the osp layer effectuates adaptation of B. burgdorferi as it gets transmitted from the tick vector to a mammalian host and vice-versa. However, the regulation of the outer surface lipoproteins (osps) is still a conundrum for borrelia scientists. Part of this dissertation inquires about the homeostatic maintenance of the osp layer. We found that the deletion of the dominantly expressed tick phase osp, OspA, induces expression of two other osps. OspD, and BBJ41. …

Mites [Of Dogs And Cats], Susan E. Little, Roberto Cortinas

School of Veterinary and Biomedical Sciences: Faculty Publications

Veterinary parasitology: 20,000-word article details recognition and treatments for mite infestations of dogs and cats. Mite species reviewed include:

Cheyletiella spp. (“Walking Dandruff”)

Demodex spp. (Hair Follicle Mites, Red Mange, Demodicosis, Demodectic Mange)

Sarcoptes scabiei (Itch Mite, Scabies, Sarcoptic Mange)

Notoedres cati (Feline Head and Neck Mange)

Otodectes cynotis (Ear Mites)

Pneumonyssoides caninum (Nasal Mite)

Lynxacarus radovskyi (Fur Mite, Hair Clasping Mite)

Trombiculid Mites (Chiggers, Red Bugs, Berry Bugs, Harvest Mites, Scrub Itch or Grass Itch Mites)

Discussions include Etiology and epidemiology, Pathogenesis, Clinical features, Diagnosis, Treatment and prognosis, Immunity, Prevention, and Public health aspects.

Complete with 209 references.

North American Hard Yellow Liver Disease: An Old Problem Readdressed, Bryan L. Stegelmeier, Meredyth Jones, Christopher P. Womack, T Zane Davis, Dale R. Gardner

Poisonous Plant Research (PPR)

Hard yellow liver disease or fatty cirrhosis periodically affects cattle, sheep, goats, pronghorn antelope (Antilocapra americana) and whitetail deer (Odocoileus virginianus texanus) within several Texas counties in the United States. Clinically it presents as chronic liver disease with progressive hepatic necrosis and fibrosis, icterus and liver failure. The damaged livers are yellow and many have multiple firm, often gritty foci that are scattered throughout all lobes. Early investigations included feeding studies using potential toxic plants, climate and forage studies, infectious disease surveys and various mycotoxin studies and analyses. None have definitively reproduced the disease or identified the inciting …

Elaeophorosis In Red Deer From Spain, Mónica Santín-Durán, J. M. Alunda, J. M. San Miguel, Eric P. Hoberg, C. De La Fuente

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Elaeophorosis, caused by Elaeophora elaphi, was observed in red deer (Cervus elaphus) from Toledo Province (Spain) for the first time. Adult specimens of Elaeophora elaphi were found in the hepatic vessels of nine of 151 red deer between October 1994 and September 1995; intensity of infection was two to 18 nematodes per host. Adult nematodes were only found during the period from fall through early spring. No differences were present between sex or age groups. Parasites were not found in a limited sample from fallow deer (Dama dama). Blood samples were negative for the presence of …

Production, Characterization, And Diagnostic Application Of Monoclonal Antibodies Against The N-Protein Of Avian Metapneumovirus Subgroup B, Ravi Gupta

Electronic Theses and Dissertations

Avian metapneumovirus (aMPV) is a respiratory pathogen that causes Turkey Rhinotracheitis (TRT) in turkeys and Swollen Head Syndrome (SHS) in chickens. The infection leads to facial swelling, nasal discharge, reduced egg production, and poor growth. This virus is classified into four subgroups: aMPV-A, B, C, and D, with two other novel subgroups, in which aMPV-A, B, and C are most prevalent in the commercial flocks. In early 2024, aMPV-A and B outbreaks have been reported in the US, resulting in severe economic losses. An economic assessment estimates around $112 million in losses in Minnesota and up to $434 million in …

Prevalence Of Tick-Borne Pathogens In Small Mammals And White-Tailed Deer In Southeast Nebraska, Tim M. Hotaling

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

The prevalence of tick-borne diseases has been increasing in the United States for the past couple decades. Studies have been conducted throughout the US identifying tick-borne disease pathogens as well as their hosts and prevalence. Research was conducted in Nebraska to determine the presence of some tick-borne disease pathogens, their vectors, and their hosts, with emphasis made on Borrelia spp., Rickettsia rickettsii, and Ehrlichia chaffeensis.

Small rodents in southeast Nebraska were trapped and sampled at eight study sites using live capture traps. Captured rodents were assessed for active parasitism by ticks which were collected and placed in alcohol. …

Comparison Of Immune Responses During Gastrointestinal Helminth Self-Cure Expulsion Between Resistant Gulf Coast Native And Susceptible Suffolk Sheep, Javier Jesus Garza

LSU Doctoral Dissertations

The immune response to the self-cure phenomenon seen during gastrointestinal nematode (GIN) parasitism of small ruminants was compared between sheep breeds that are resistant or susceptible to Haemonchus contortus infection. Fifty-four Gulf Coast Native (resistant) and Suffolk (susceptible) lambs were allowed to acquire a natural GIN infection on pasture and were then randomly allocated into 4 groups. After being moved to parasite free housing for 2 months, lambs were given a challenge infection of 20,000 H. contortus L3. Fecal egg counts (FEC) were monitored throughout the study and animals were necropsied at 0, 1, 3, and 7 days post infection …

Development Of A Subunit Vaccine Against Bovine Diarrhea Caused By K99 Enterotoxigenic Escherichia Coli And Bovine Viral Diarrhea Virus, Emad Hashish

Electronic Theses and Dissertations

Bovine diarrhea is economically one of the most important problems in cattle industry. Enterotoxigenic Escherichia coli (ETEC), particularly strains expressing K99 (F5) fimbriae and heat-stable type I (STa) enterotoxin is the predominant bacterial cause of diarrhea in calves; whereas bovine viral diarrhea virus (BVDV) causes diarrhea and other illness to cattle at all ages. A vaccine that prevents against both K99 fimbrial ETEC and BVDV could benefit greatly to cattle producers worldwide. We hypothesized that a novel multivalent vaccine composed of K99, STa and BVDV E2 antigens could induce immunity for broad protection against bovine diarrhea. In this study we …

Improved Methods For The Isolation And Characterization Of Flavobacterium Columnare, Bradley Donovan Farmer

LSU Master's Theses

Columnaris disease, caused by the bacterium Flavobacterium columnare, is an economically significant problem in many warmwater fish species. Difficulties encountered in the isolation and culture of F. columnare have been an impediment to research on the organism and the disease it causes. The goal of this study was to improve the methods for isolation, culture, identification and maintenance of F. columnare. Following the evaluation of different culture media selective cytophaga agar was determined to be the optimum isolation medium, Flavobacterum columnare growth medium proved to be the optimum culture medium, and tryptone yeast extract agar with increased moisture was best …