The genome of a Korean isolate of Hepatopancreatic parvovirus (HPV) was partially cloned, sequenced and characterized. Random PCR amplification of viral DNA was combined with conventional cloning methods to generate three clones named HPV8 (2,136 bp insert), HPV3 (1,560 bp insert), and CP1139 (413 bp insert). DNA sequencing demonstrated overlapping regions between HPV8 and HPV3 and between HPV3 and CPII39. The combined sequence of these three clones encompass approximately 3,350 bp of the total 5,000 bp estimated for the HPV genome. A large open reading frame (1,692 bp) was found within clones HPV3/CPII39 encoding a polypeptide of 549 residues (∼60 kDa) whose amino terminus shows 100% homology with the first 12 residues sequenced from an apparently single 54 kDa (by SDS-PAGE) structural protein found in a Korean isolate of HPV. Two new gene probes EC.592 (592 bp) and EC.350 (350 bp) were developed by PCR amplification of previously constructed HPV (Korean) clones and labeled with DIG11-dUTP. These probes recognize different regions of the HPV genome. The specificity of both probes was confirmed by in situ hybridization using HPV-infected Penaeus chinensis (Korean) as a positive control and specific-pathogen free P. vannamei and IHHNV-infected P. stylirostris, as negative controls. Both probes were used in in situ hybridization to compare their reaction to HPV-type lesions detected by conventional H&E histology in 7 species of HPV-infected shrimp, and one of freshwater prawn, from 13 countries. The results of this comparison strongly suggest the existence of genomic differences among these geographic isolates. A post-embedding in situ hybridization assay at the electron microscope level was developed to detect HPV nucleic acids on HPV-infected hepatopancreata from P. chinensis and P. monodon . Hybridized probe (EC.592) was detected with an anti-DIG sheep antibody conjugated to 10 nm gold particles and subsequent silver enhancement. Hybridization signal was observed within HPV-infected hepatopancreatic cells, which was specifically located within intranuclear viral inclusions, cytoplasm, microvillous border, and associated to necrotic debris within the lumen of hepatopancreatic tubules. A non-destructive method, based on the PCR, was developed to detect HPV by examination of crude fecal samples from HPV-infected shrimp.

Le souffle équin est une maladie inflammatoire chronique des petites voies respiratoires, très fréquente chez les chevaux gardés à l’intérieur avec de la paille et du foin moisi et poussiéreux. Les signes cliniques peuvent être prévenus par le contrôle de l’environnement et soulagés par l’administration de corticostéroïdes systémiques et inhalés. L’objectif de cette étude était de déceler les effets secondaires présents sur des chevaux atteints de souffle traités à la fluticasone (Flovent 250 μg HFA®, 2000 μg BID, pendant six mois, et puis 2000 μg SID, pendant six autres mois) par le cortisol sérique et la présence d’ulcères gastriques. Cinq chevaux exempts de maladie respiratoire et onze chevaux atteints du souffle ont été gardés à l’intérieur d’une écurie avec du foin moisi et de la paille dans le but de provoquer la maladie chez le groupe atteints du souffle. Une fois les chevaux atteints de souffle devenus symptomatique, ils ont été divisés en deux groupes : un premier groupe traité avec de la fluticasone, nourri avec du foin et gardé sur une litière de paille, et un deuxième groupe non traité nourrie avec de la moulée et gardé sur une litière de ripe, pendant six mois. Par la suite, les deux groupes ont été mis au pâturage. Le cortisol a été mesuré par Immunoessai enzymatique par chimiluminescence (CEIA, Immunolite 1000, Siemmens®) les 12e et 10e jours avant et les 7e, 28e, 80e, 160e, 200e, 250e, 290e et 320e jours après le début du traitement afin de déterminer le degré de suppression du cortisol sérique. On a également fait une suivi de la présence d`ulcères gastriques à l`aide de vidéo endoscopique. La fluticasone inhalée deux fois par jour cause une diminution du cortisol sérique les 28e, 80e et 160e jours, mais elle n’entraîne pas d’effets sur le score des ulcères gastriques. Les pellets de luzerne causent quant à elles, une augmentation du score des ulcères gastrique chez les animaux exempts de maladie respiratoire. / Recurrent Airways Obstruction (RAO) is a small airways inflammatory disease, very common in horses stabled in mouldy-dusty hay and straw environments. The clinical signs are prevented by environmental control, relieved by systemic and inhaled corticosteroids. Our objectives were to determine whether inhaled corticosteroids cause a suppression of cortisol levels and gastric ulceration in RAO horses treated with fluticasone 2000μg (Flovant HFA®) BID for 6 months and 2000μg SID for another 6 months. Five (5) healthy horses were used as controls and eleven (11) RAO affected horses were stabled in a moldy-dusty environment to induce disease exacerbation. Once they were symptomatic, they were divided into two groups, the treated group was kept on hay/straw and the untreated group was fed with pellets food and bedded on wood shavings six months. Afterwards, all horses were pasture for the next 6 months. Serum cortisol was mesured by Immuno-essai enzymatique par chimiluminescence (CEIA, Immunolite 1000®, Siemmens) 12, 10 days before and 7, 28, 80, 160, 200, 250, 290, 320 days after treatment initiation, in order to determine cortisol suppression. Fluticasone administered twice a day reduces blood cortisol levels after 28, 80 and 160 days, but did not cause any change in gastric ulcers. However, pellets slightly increased gastric ulcer scores in healthy horses.

<p> Several lines of evidence suggest that pigs act as a reservoir of hepatitis E virus (HEV). This dissertation presents data from studies conducted from August 2010 &ndash; August 2011 in Nan, Thailand. These studies define the previously unknown burden of HEV in pig and human populations in Nan province, and evaluate the transmission of HEV among humans having direct or indirect contact with the reservoir in pig. This work begins with a literature review. The first study addressed the risks for HEV transmission between pigs in different sized farms, and possible risk factors among pigs in a cross-sectional study. This study found a 9.9% (87/879) seroprevalence of anti-HEV among pigs and 2.9% of pigs had HEV ribonucleic acid (RNA) positive fecal samples. All HEV sequences corresponded to genotype 3. Pigs raised on medium sized farms with 30-300 pigs per farm had higher anti-HEV seroprevalence than pigs raised on larger farms with over 300 pigs after controlling for other potential confounders. Better hygienic practices were used in larger farms compared with small or medium sized farms. The second study addressed the association between occupational pig exposure to HEV infection among farmers over the age of 15 and the general population without direct contact with pigs in a cross-sectional study. The overall prevalence of anti-HEV was 23.0% (118/513). There was no association between anti-HEV prevalence and direct exposure to pigs. Frequent consumption of organ meat &ge; 2 times per week was a significant risk factor for HEV seroprevalence, adjusted odds ratio (OR) 3.23, 95% confidence interval (CI) 1.15, 9.01. Serum samples from all subjects with recent symptoms compatible with hepatitis who were IgM anti-HEV positive among the farmers and 40 serum samples from the control unexposed group with the highest mean optical density (OD) value were evaluated for HEV RNA by reverse transcriptase polymerase chain reaction (RT PCR). None of the samples were HEV RNA positive. These studies establish that HEV is endemic among pig populations in Nan province. It appears that HEV infections in humans are acquired more frequently as a food-borne infection than by direct contact with pigs in this population. </p>

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6121. Adviser: Peter James Garlick. Includes bibliographical references (leaves 72-89) Available on microfilm from Pro Quest Information and Learning.

Doctor of Philosophy / Department of Anatomy and Physiology / David C. Poole / Exercise-induced pulmonary hemorrhage (EIPH) or epistaxis has been recognized in racehorses since the 16th century. Since this time, great strides have been made in terms of identifying the lungs as the source of the hemorrhage via the endoscope, utilization of bronchoalveolar lavage to quantify the hemorrhage, and the discovery of successful treatments such as furosemide and the nasal strip that ameliorate, but do not abolish EIPH. It has been determined that, in addition to extremely high pulmonary arterial pressures and the negative intrapleural pressures being the major physiologic forces causing pulmonary capillary stress failure, other factors have the potential for influencing the severity of EIPH including locomotory impact trauma, inflammatory airway disease (IAD), upper airway obstruction, coagulation anomalies, and high blood viscosity. It has been hypothesized that EIPH is detrimental to performance and this was recently confirmed by Hinchcliff et al. in 2004. EIPH is a complex multi-factorial condition with much still unknown about the etiology, best method for diagnosis, and most effective form of treatment. Chapter one of this dissertation determined the effectiveness of a novel treatment, concentrated equine serum, in ameliorating EIPH via reduction of IAD. Chapter two refuted the hypothesis that herbal formulations commonly used in the field with anecdotal success would decrease EIPH by correcting coagulation deficits during exercise, as scientific efficacy was not evident, at least at the dose and duration used in our investigation. Chapter three addressed the dogma that EIPH only occurs during maximal intensity exercise, and in demonstrating significant EIPH during sub-maximal exercise, emphasized the role that the airways play in contributing to the initiation and severity of EIPH. Chapter four examined the occurrence and severity of EIPH in the horse’s canine counterpart, the racing Greyhound. The demonstrated presence of mild EIPH in the Greyhound, a physiologically similar yet different athlete in comparison to the horse sheds new light on the etiology of this condition in both species. The results of these investigations have advanced the frontiers of our knowledge concerning EIPH. Specifically, they have generated novel information on the mechanistic bases of EIPH and have provided evidence supporting additional treatment options for reducing the severity of EIPH in horses.

Doctor of Philosophy / Department of Family Studies and Human Services / Anthony Jurich / Until recently, minimal research has been done regarding the impact of veterinary student stress on the student’s significant intimate relationships. In this study of 466 veterinary students enrolled in five different accredited U.S. Colleges of Veterinary Medicine, the association of five primary variables, perceived stress, self-esteem, academic satisfaction, relationship satisfaction, and general life satisfaction was investigated, utilizing McCubbin and Patterson’s (1983) Double ABCX Model as a guide. Six of the seven hypotheses were supported and further regression analysis yielded a model of variable associations that supported the Double ABCX Model, though significant gender differences were found. Specifically, female students perceived significantly more stress than did male students. With the exception of academic satisfaction and relationship satisfaction, all of the major variables were strongly correlated with each other. For the women, who comprised a significant majority of the sample, perceived stress had a significant impact on relationship satisfaction, as well as on self-esteem, which in turn significantly impacted academic satisfaction. Relationship satisfaction and academic satisfaction both significantly, and separately, impacted general life satisfaction, suggesting that relationship satisfaction and academic satisfaction are different constructs that operate independently of each other. However, both have a significant impact upon and are significantly associated with general life satisfaction, suggesting that neither can be neglected during veterinary training if a positive outcome is desired. For the men in this sample, stress impacted directly upon academic satisfaction, self-esteem, and general life satisfaction but did not have a direct impact upon relationship satisfaction. Instead, relationship satisfaction and general life satisfaction had a highly correlated relationship, with both significantly and strongly associated with the other. Although academic satisfaction and relationship satisfaction appear to be two separate entities, they are both important elements to achieving general life satisfaction during veterinary training and, therefore, should be equally attended to during the training process. These findings are interpreted and discussed in light of the implications for and importance of continued collaboration between veterinary students and programs and the field of Marriage and Family Therapy in an effort to understand and support students and their significant relationships during the veterinary training process.

Master of Science / Department of Clinical Sciences / Michael W. Sanderson / A Monte Carlo model was developed to determine the cost-effectiveness of different biosecurity strategies for Bovine Viral Diarrhea Virus (BVDV) on cow-calf farms. Where possible, risk distributions were defined in the course of a critical literature review covering all publications since 1990 relevant to BVDV on cow-calf farms. The prevalence of persistent infections (PIs) in adult cows was unknown, so a survey of viremia in 2,990 adult cows for sale in the Midwest during 2006 was performed; prevalence was calculated to be 0.07%. In order to validate a newly developed RT-nPCR for pooled serum used for the survey, sensitivity was determined based on 100 known viremic serum samples; sensitivity was 95%, with no detectable effect of strain type. A Monte Carlo model was developed to calculate the risk of introducing BVDV to a cow-calf herd and number of PIs introduced in one year, based on herd imports and biosecurity strategies. The results of that model were integrated with a stochastic SIR model for the spread and impact of BVDV through a cow-calf herd over 10 years, based on herd size and control strategies. The resulting model was integrated with a stochastic model for the cost of both the biosecurity and control measures used and the financial impact of BVDV infection on the herd over 10 years. The lowest risk option of 14 biosecurity strategies were calculated for 400-, 100-, and 50-head herds with 8 different import profiles, and management factors that increase financial risk due to BVDV were determined.

Master of Science / Department of Clinical Sciences / Michael Sanderson / Biosecurity, biocontainment and security practices are important in production animal agriculture. Procuring cattle from multiple sources and commingling them into a single confinement operation increases risk of disease introduction. The large concentration of animals makes a feedyard a more likely target of a domestic or international terror group. Controlling or eradicating an intentionally introduced pathogen or toxin would be costly. The aim of these surveys was to gather information from experts about perceived risks and mitigation strategies and to assess current practices of biosecurity, biocontainment and security in Central Plains feedyards. Consulting veterinarians and feedyard managers shared similar views on the likelihood of disease caused by terrorism, natural introduction or accidental introduction, and on the importance of on-site security. They disagreed on the importance of preventative products, disease transmission control, and environmental control. Generally speaking, feedyard managers believed environmental control to be more important than consulting veterinarians. In reference to a survey of current practices, some feedyards use equipment for both manure and feed handling. Many feedyards are not cleaning and disinfecting oral treatment equipment, treatment facilities, or unloading facilities on a regular basis which may increases their risk for indirect disease transmission of endemic agents such as Salmonella or BVDV. Most feedyards in this survey import some cattle directly from an auction market, do not require clean boots or foot covering to be worn by visitors, and do not require trailers to be cleaned. Smaller feedyards were more likely to require trailers to be cleaned before loading incoming cattle. Less than half of the feedyards reported having a fence that will stop humans or kept protein supplements or micro-nutrients secured from access. Some feedyards enforced a visitor log or employed a night watchman. Most feedyards learned about a future employee by calling references listed in resume, but some performed a criminal background check. A cost-benefit analysis should be done on all management practices to determine economic benefits. More research is needed to better understand which practices are most beneficial.

Master of Science / Department of Diagnostic Medicine/Pathobiology / Daniel U. Thomson / Escherichia coli O157:H7 is a human food-borne pathogen and cattle feces are a major source of contamination. Immunization against E. coli O157 may be a practical pre-harvest intervention strategy. A siderophore receptor/porin proteins (SRP) based vaccine has been developed to decrease the prevalence of E. coli O157 in cattle. Two studies were conducted to determine the efficacy of the SRP vaccine. In the first study, thirty calves were randomly assigned to one of two groups: control or SRP vaccine. Two weeks after the second vaccination, calves were orally inoculated with nalidixic acid-resistant (Nal[superscriptR]) E. coli O157. Fecal samples were collected for five weeks. Calves were necropsied on day 35 to collect gut contents and tissue swabs to determine Nal[superscriptR] E. coli O157:H7. The number of calves that were culture positive for E. coli O157 were lower (P= 0.07) in vaccinated group compared to the control. In the second study, cattle in two feedlots were randomized to SRP vaccine or control. Cattle were vaccinated on days 0 and 21. Rectal fecal samples were collected on day 0, and pen floor samples were collected on days 21, 35, and 70. Rectal fecal samples, RAMS, and hide swab samples were collected on d 85. Cattle were weighed on days 0, 21, and 85. Vaccination significantly reduced (P = 0.04) fecal E. coli O157 prevalence. There was also a decrease (P < 0.05) in E. coli O157 prevalence on hides and in fecal samples on day 85 in vaccinated cattle compared to the control.

Doctor of Philosophy / Department of Anatomy and Physiology / A. Philine Wangemann / Pendred syndrome is characterized by sensorineural deafness and post-pubertal goiter. It is caused by mutations in the anion exchanger, pendrin (SLC26A4). The purpose of this study was to understand the etiology of Pendred syndrome using a mouse model. Different methods of amplification from nanogram amounts of starting RNA were evaluated for gene array application. Gene arrays were performed and free radical stress markers were compared between the stria vascularis and the thyroid of the Slc26a4+/- and Slc26a4-/- mice. Hearing loss in Slc26a4-/- mice is linked to the loss of Kcnj10 protein expression and consequently the loss of endocochlear potential. To understand the mechanism of hearing loss in Slc26a4-/- mice, progressive loss of Kcnj10 protein expression in stria vascularis of Slc26a4-/- mice was assessed, the modulation of Kcnj10 protein expression by free radical stress in cultured stria vascularis and in an heterologous expression system was evaluated. To characterize the thyroid pathology, pendrin expression in the thyroid of Slc26a4+/- mice was measured in a developmental study and correlated with serum thyroxine (T4) levels of Slc26a4+/- and Slc26a4-/- mice over a developmental time course. All tested methods of RNA amplification were suitable for gene array application and demonstrated high internal consistency. Intermethod comparisons revealed variations in data, suggesting that a single amplification method ought to be used within a given experiment. Markers of free radical stress were increased in the stria vascularis of Slc26a4-/- mice before the onset of hearing. Progressive loss of Kcnj10 expression was seen in Slc26a4-/- mice at the onset of hearing. Furthermore, free radical stress modulated the expression of Kcnj10 in cultured stria vascularis and in a heterologous expression system. The pendrin mRNA expression was marginal in the thyroid and did not correlate with serum T4 levels. Further, absence of pendrin did not affect free radical stress markers in the thyroid. These data suggest that free radical stress-mediated loss of Kcnj10 expression in stria vascularis contributes to deafness in the Pendred syndrome mouse model and that pendrin is not essential for the function of mouse thyroid gland.