Veterinary Medicine Commons^™

Raccoon Density Estimation From Camera Traps For Raccoon Rabies Management, Amy J. Davis, Wesley C. Dixon, Richard B. Chipman, Amy T. Gilbert, Jacob E. Hill, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

Density estimation for unmarked animals is particularly challenging, yet density estimates are often necessary for effective wildlife management. Raccoons (Procyon lotor) are the primary terrestrial wildlife reservoir for Lyssavirus rabies within the United States. The raccoon rabies variant (RRVV) is actively managed at landscape scales using oral rabies vaccination (ORV) within the eastern United States. To effectively manage RRVV, it is important to know the density of raccoons to appropriately scale the density of ORV baits distributed on the landscape. We compared methods to estimate raccoon densities from camera‐trap data versus more intensive capture‐mark‐recapture (CMR) estimates across 2 …

Surveillance Of Highly Pathogenic Avian Influenza Virus In Wild Canids From Pennsylvania, Usa, Kevin D. Niedringhaus, Taylor C. Chan, Ashley Mcdowell, Lauren Mxwell, Madison Stevens, Lane Potts, Erica Miller, Eman Anis, Kyle Van Why, Thomas Keller, David Stallknecht, Rebecca L. Poulson, Kaitlyn Bahrs, Justin D. Brown

United States Department of Agriculture Wildlife Services: Staff Publications

The avian influenza virus is a global pathogen with significant health and economic implications. While primarily a pathogen of wild and domestic birds, recent outbreaks of the H5N1 highly pathogenic avian influenza virus (HPAIV) clade 2.3.4.4b have caused mortality in a wide variety of mammals, including members of the Canidae family, on multiple continents. Despite sporadic mortality events globally, the epidemiology and pathobiology of H5N1 HPAIV in wild canids remains poorly defined. During 2022–2024, 41 wild canid carcasses (diagnostic cases), including 23 red foxes and 18 gray foxes, were tested for the influenza A virus (IAV) via PCR, with five …

Rabies, Amy T. Gilbert, Christine Ellis

United States Department of Agriculture Wildlife Services: Staff Publications

Illustrated fact sheet on rabies.

Evaluating The Efficacy Of An Early Vaccination Strategy After Farrowing Using A Modified Live Prrs Vaccine And Post-Weaning Challenge With Thai Hp-Prrs, Apichart Prapattanakullawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major pathogen responsible for substantial economic losses in the global swine industry, adversely affecting both reproductive and respiratory health. In Thailand, early PRRSV infections in suckling and nursery pigs are commonly observed, necessitating the implementation of early vaccination strategies. However, early vaccination in young piglets has been controversial due to concerns about interfering maternal-derived antibodies (MDA) and the competency of the piglets' immune system. The objective of this study is to evaluate the efficacy of a modified-live virus (MLV) PRRS vaccination in early-age piglets from PRRSV-positive farms by assessing immune responses …

Genotypic Characterization And Amr Risk Assessment Of Esbl- Producing And Fluoroquinolone-Resistant Salmonella Spp. From Pork Collected In Bangkok, Thawanrut Kiatyingangsulee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to 1) determine the prevalence of ESBL-producing and fluoroquinolone-resistant Salmonella in pork, 2) investigate their genomic characteristics, and 3) estimate the risk of consumer exposure. Pork samples were collected from 58 markets across 19 districts in Bangkok. The study focused on third-generation cephalosporin resistance mediated by ESBLs and fluoroquinolone resistance, representing horizontal and vertical gene transfer, respectively. Out of 793 pork samples, 339 (42.8%) were positive for Salmonella, yielding 531 isolates from 33 serotypes. The most common were Salmonella Rissen (22.6%), Sinstorf (16.8%), and Derby (10.2%). Antimicrobial susceptibility testing showed 28.2% of isolates were ESBL producers and …

Efficacy Of Cell-Free Supernatants Based Nano-Application From Thai Probiotic Bacteria As An Alternative Preservative In Meat Against Foodborne Pathogens, Thin Zar Soe

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study evaluates whether the use of cell-free supernatants (CFS) derived from Thai probiotic bacteria as natural preservatives in meat products, provides a safer alternative to chemical preservatives. The objectives include developing a nano-encapsulation technique to enhance the stability and efficacy of CFS, and assessing the effectiveness of nano-encapsulated CFS (Nano-CFS) in maintaining meat safety and quality during storage and evaluating the antibacterial efficacy of CFS and (Nano-CFS) against common foodborne pathogens, determining the minimal inhibitory and bactericidal concentrations (MIC and MBC). The CFS was prepared from the Thai probiotic strains. Antibacterial activity was determined using agar well diffusion and …

Genomics Approach For Ex Situ Conservation Of Asian King Vulture And Steppe Eagle, Wannapol Buthasane

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Asian king vulture (Sarcogyps calvus, AKV), an ecologically important forest scavenger, is an Old World vulture in the family Accipitridae. It is classified as a critically endangered species, with no genomic data currently available. This dissertation aimed to assemble a high-quality reference genome to enhance understanding of its genetic background, scavenging adaptations and genetic diversity within Thailand’s captive population. A hybrid genome assembly combining Pacific Biosciences (PacBio) long-read and MGI short-read sequencing was generated from DNA extracted from the whole blood of a female individual. Comparative genomic analyses with New World vultures (NWVs) and other Accipitridae species revealed distinct …

Ultrasonographic Renal Cortical Thickness To Abdominal Aorta Internal Diameterin Healthy Cats And Chronic Kidney Disease Cats, Run Sakulsirajit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Chronic kidney disease (CKD) is a one of the most common disorder in cats, particularly in aging populations. Early detection and accurate monitoring are crucial for effective disease management. This study aims, first, to evaluate the ultrasonographic parameters, including renal cortical thickness (RCT), medullary thickness (MT), renal length (RL), abdominal aorta diameter (Ao) and ratios, including RCT/Ao, RCT/MT, RCT/RL, MT/Ao and RL/Ao compared between clinically healthy and CKD cats. Second, to evaluate the correlations of ultrasonographic parameters with blood renal functions including blood urea nitrogen (BUN), creatinine (Cr) and symmetric dimethylarginine (SDMA) and also correlation with age, body weight (BW) …

Improving Antimicrobial Susceptibility Testing Of Arcobacter Butzleri: Comparative Methods And Epidemiological Cut-Off Value (Ecoff) Determination, Myzatul Hanis Zahiyah Yusof

Chulalongkorn University Theses and Dissertations (Chula ETD)

Arcobacter butzleri is an emerging zoonotic pathogen associated with gastrointestinal illnesses in humans, yet standardized antimicrobial susceptibility testing (AST) methods and interpretive breakpoints for this microorganism remain unavailable. Broth microdilution, despite being endorsed by the CLSI-VAST subcommittee, is often impractical in several laboratories. Therefore, this study aimed to evaluate agar dilution as a more feasible alternative to broth microdilution. A total of 415 A. butzleri isolates from various meat sources in Bangkok, Thailand were confirmed by PCR and tested against ciprofloxacin, erythromycin, gentamicin, and tetracycline. AST was conducted using broth microdilution under aerobic conditions for 24 hours as the reference …

Complete Genome Analysis Of African Swine Fever Virus Strains In Thailand, Anwesha Prakash

Chulalongkorn University Theses and Dissertations (Chula ETD)

African Swine Fever Virus (ASFV) is a large double-stranded DNA virus responsible for the highly contagious and lethal African Swine Fever (ASF), affecting the global porcine industry. The virus has a genome length of 170-194 kb and is broadly categorized into the left variable region (LVR), the right variable region (RVR), and the central conserved region (CCR). In Thailand, ASF was officially confirmed in January 2022 and identified as genotype II, which is primarily responsible for the current Eurasian swine pandemic. To date, due to the absence of a globally accepted vaccine against ASFV, culling and quarantine remain the primary …

Canine Cricoid Cartilage And Tracheal Dimensions Observed On Computed Tomographic Image, Tanya Kasemsuwan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Inhalation anesthesia is commonly used for general anesthesia due to its effectiveness. During the procedure, an endotracheal tube (ET) is essential for maintaining anesthetic depth, delivering anesthetic agents, and providing sufficient oxygen to reduce the risks of morbidity and mortality. Mispositioning and inappropriate ET size can lead to complications like hypoxemia, hypercapnia, and airway trauma. Commercially available ET tubes are designed for general use and are not specifically optimized for different cephalic types, leading to the objective of this study, which was to investigate the differences in anatomical dimensions of the cricoid cartilage and trachea and ET location among brachycephalic, …

Determination Of Nutrients Digestibility In Commercial Dry Dog Food Containing Various Protein Sources, Phuong Anh Ta

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study evaluated the nutritional adequacy and digestibility of commercial dry dog foods formulated with different protein sources (animal versus plant) and market tiers (premium versus economy). Eight commercial dog foods were analyzed for nutrient composition and amino acid profiles using proximate analysis and high-performance liquid chromatography (HPLC). Of these, four representative products were selected to assess digestibility through in vivo total fecal collection in Beagle dogs and in vitro digestion assays. All products exceeded 18% crude protein (the minimum crude protein requirement by AAFCO). However, deficiencies were examined in essential amino acids, particularly leucine, isoleucine, methionine, lysine, tryptophan, valine …

The Comprehensive Study Of The Reproductive Cycle With A Special Focus On The Vestibular Microbiome In Captive Asian Elephants (Elephas Maximus), Yuqing Yang

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation aimed to advance the understanding of reproductive physiology and health in Asian elephants, providing critical insights and innovative methodologies for reproductive management. Chapter II established a foundational framework for normal reproductive cycling, detailing the luteal and follicular phases, and introduced a simplified, practical body condition score (BCS) method as a diagnostic tool for assessing general health and welfare. It highlighted unresolved reproductive issues, such as abnormal cycling, and revealed that progesterone peaks, with the majority (53.57%), and the onset of the follicular phase predominantly occurred during the rainy season. Monitoring ovulation and maintaining a standard BCS during the …

Molecular Investigation And Genetic Characterization Of Hemotropic Mycoplasma Spp. And Potential Role Of Flea Vectors In Goats In Thailand, Muhammad Shair Zaman Ghauri

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to investigate the identification of flea species infesting goats and to study the molecular prevalence and genetic characterization of hemotropic mycoplasmas in goats and fleas. A total of 500 blood and 79 flea samples were collected from goat farms across seven provinces in Thailand between January 2017 and October 2023. Among the 500 goats examined, 6.6% were infested with fleas, which were morphologically identified and molecularly characterized using mitochondrial (cox-I, cox-II) and nuclear (ITS1, EF-1α) markers as Ctenocephalides orientis. Additionally, 14,315 bp fragment of the C. orientis mitochondrial genome was analyzed, revealing a close evolutionary relationship with …

Detection Of Brafv595e Gene Of Canine Urothelial Carcinoma Using Real-Time Pcr, Monticha Kitnitchee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Canine urothelial carcinoma (CaUC) is the most common malignant tumor of the urinary bladder in dogs. This cancer has aggressive behavior and it is challenge for diagnosis. Most CaUC cases are diagnosed from the obvious clinical signs as the late to advance stage. In addition, therapeutic strategies for this stage are almost non-responsive for the eradication and prevention of recurrent disease. Therefore, non-invasive early diagnosis is required for urothelial carcinomas in both human and animals including dogs, which have similar cancer biology to human. This study aimed to evaluate diagnostic accuracy by BRAFV595E detection using real-time PCR (qPCR) from various …

Alternative Approaches To Replace Antibiotics Use In Boar Semen Extenders And Their Effects On Reproductive Performance, Congbang Ngo

Chulalongkorn University Theses and Dissertations (Chula ETD)

Artificial insemination (AI) with antibiotic-free alternatives in boar semen extenders is becoming essential for promoting environmentally sustainable practices in the global swine industry. Comprising 4 parts, this thesis aimed to investigate the boar fecal and seminal microbiomes in relation to semen quality and probiotic supplementation in an antibiotic-free feeding program. In addition, the characteristics of semen doses treated with alternative methods and their effects on the reproductive performance of sows inseminated with these semen doses are examined. (i) To investigate the fecal and seminal microbiomes of boars in relation to semen quality and the effects of transitioning from antibiotics to …

Validation Of A Pseudotype-Based Serum Neutralization Test Forpeste Des Petits Ruminants Virus (Pprv) Specific Antibody In Goat Sera, Suphatcha Mahawattana

Chulalongkorn University Theses and Dissertations (Chula ETD)

Peste des petits ruminants (PPR) is a transboundary viral disease in small ruminants, caused by a morbillivirus called peste des petits ruminants virus (PPRV). Recently, FAO and WOAH have set the goal to eradicate the disease in 2030. To maintain disease vigilance, the Department of Livestock Development conducts regular screenings for anti-PPRV antibodies using a commercially available competitive ELISA (cELISA). However, limitation from its window of uncertainty could lead to inconclusive result. In this study, a recently developed pseudotype-based neutralization test was validated against a large number of known positive and negative samples. In comparison with the cELISA, from 416 …

Effect Of Four Non-Slipping Floor Mat Types On The Stifle Joint Range Of Motion During Walking And Trotting In Small Breed Dogs With Medial Patellar Luxation Grade 2 And Normal Stifle Dogs, Panisara Wongsirichatchai

Chulalongkorn University Theses and Dissertations (Chula ETD)

The two dimension kinematic motion analysis was an accessible tool for clinical approach for assist gait analysis and joint mobility in veterinary clinical field. Thermographic imaging also considered as an adjunctive non-invasive technique to detects changed superficial temperature from the physiological associated with inflammation or musculoskeletal conditions especially in joints, tendon, or muscle. A comparing controlled experiment investigated the effects of various ceramic flooring surfaces on gait, stifle joint mobility, and post-activity inflammatory response following activity in small breed dogs with and without grade 2 medial patellar luxation (MPL).Sixteen small breed dogs were enrolled, including normal stifle dogs (n=7) and …

Proteomic Analysis Of Canine Reproductive Protein Profiles In Relation To Stage Of Oocyte Development, Larindhorn Udomthanaisit

Chulalongkorn University Theses and Dissertations (Chula ETD)

The domestic dog has a unique reproductive physiology in which oocytes are ovulated at an immature stage and complete nuclear maturation within the oviduct approximately 48–72 hours after ovulation. This thesis aimed to investigate proteomic changes in both serum and oviductal secretions associated with oocyte development, using a combination of natural and hormonally induced ovulation models. To evaluate dynamic changes in serum proteins across the estrous cycle, samples from healthy bitches in four stages—anestrus, proestrus, estrus, and diestrus—were analyzed, revealing 38 significantly altered proteins. Among these, eight exhibited stage-specific expression patterns, including HES2, ADGRA3, and SWI5 in anestrus; polycystin receptors …

Selection Of Lactic Acid Bacteria Probiotics From Thai-Chick And Their Efficacy In Restoring Gut Microbiome And Salmonella Reduction In Broiler Challenged With Salmonella Typhimurium, Benjamas Khurajog

Chulalongkorn University Theses and Dissertations (Chula ETD)

Antimicrobial resistance (AMR), food safety, and sustainable poultry farming are critical global concerns driving the exploration of probiotics as alternatives to antibiotics. This study focused on the isolation, characterization, and evaluation of lactic acid bacteria (LAB) strains and the performance of two probiotics—ProCU (a blend of locally isolated LAB strains) and TOP GUT (a commercial Clostridium butyricum product)—in mitigating Salmonella infection, improving growth performance, and modulating the gut microbiota and resistome in broiler chickens. From 91 LAB isolates identified in chicken feces across Thailand, five strains (Ligilactobacillus salivarius BF12 and Pediococcus acidilactici BF9, BF14, BYF20, and BYF26) exhibited strong tolerance …

Monitoring And Characterization Of Colistin-Resistant And Extended-Spectrum Β-Lactamase-Producing Escherichia Coli And Salmonella Spp. In The Standard Slaughtering Processes., Imporn Saenkankam

Chulalongkorn University Theses and Dissertations (Chula ETD)

The rise of antimicrobial-resistant pathogens in the pig production chain poses significant threats to public health and food safety, particularly involving Salmonella and extended-spectrum β-lactamase-producing (ESBL-Ec), colistin-resistant ESBL-Ec. The slaughterhouse serves as a critical point for monitoring and preventing bacterial dissemination to humans. This study comprehensively examined the prevalence, antimicrobial resistance (AMR) profiles, and genomic characteristics of these pathogens across two pig slaughterhouses in Thailand—one operating under Hazard Analysis and Critical Control Points (HACCP) standards and the other certified only under Good Manufacturing Practices (GMP). A total of 570 samples from feces, carcasses, and environmental sources were analyzed. Salmonella prevalence …

Invasive Wild Pig (Sus Scrofa) Diets On Barrier Islands In The Southeastern United States, Vienna R. Canright, Antoinette J. Piaggio, James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Background

Biological invasions are a leading cause of reductions in global biodiversity. Islands are particularly sensitive to invasions, which often result in cascading impacts throughout island communities. Wild pigs (Sus scrofa) are globally invasive and pose threats to numerous taxa and ecosystems, particularly for islands where they have contributed to declines of many endemic species. However, the impacts of wild pig diet on the flora and fauna remain understudied in many island systems.

Results

We used DNA metabarcoding of wild pig fecal samples to quantify the seasonal diet composition of wild pigs on three barrier islands in the …

Characterizing Feral Swine Movement Across The Contiguous United States Using Neural Networks And Genetic Data, Rachael M. Giglio, Courtney F. Bowden, Ryan K. Brook, Antoinette J. Piaggio, Timothy J. Smyser

United States Department of Agriculture Wildlife Services: Staff Publications

Globalization has led to the frequent movement of species out of their native habitat. Some of these species become highly invasive and capable of profoundly altering invaded ecosystems. Feral swine (Sus scrofa × domesticus) are recognized as being among the most destructive invasive species, with populations established on all continents except Antarctica. Within the United States (US), feral swine are responsible for extensive crop damage, the destruction of native ecosystems, and the spread of disease. Purposeful human-mediated movement of feral swine has contributed to their rapid range expansion over the past 30 years. Patterns of deliberate introduction of …

Discovery Of A Novel Invasive Rodent Species On Wake Atoll With A Desert Southwest Usa Origin, Antoinette J. Piaggio, Eric Lanners, Daniel R. Taylor, Aaron B. Shiels, Marjorie Matocq, John Eisemann

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive species, particularly omnivorous rodents, have damaged island ecosystems around the world. The unique flora and fauna of island systems have typically not evolved with omnivorous rodents and are heavily impacted by their introduction. Wake Atoll of the southern Pacific Ocean is a 707-hectare coral island complex of three islands managed by the United States Department of Defense (DoD). DoD restricts civilian access to the atoll but aircraft and seacraft regularly visit the island to transport military equipment and to sustain the year-round military and contractor personnel stationed on the atoll. Wake Atoll had been invaded by Rattus rattus complex …