Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc.
Publisher:
American Association of Veterinary Laboratory Diagnosticians. Thousand Oaks, CA : Sage (2011)
Frequency: Bimonthly, 1999-
Country: United States
Language: English
Author(s):
American Association of Veterinary Laboratory Diagnosticians.
Start Year:1989 -
ISSN:
1040-6387 (Print)
1943-4936 (Electronic)
1040-6387 (Linking)
1943-4936 (Electronic)
1040-6387 (Linking)
Impact Factor
1.5
2022
| NLM ID: | 9011490 |
| (DNLM): | SR0065989(s) |
| (OCoLC): | 18477067 |
| LCCN: | sn 88008583 |
| Classification: | W1 JO97N |
Clostridium piliforme infection (Tyzzer disease) in horses: retrospective study of 25 cases and literature review. Tyzzer disease (TD) is caused by Clostridium piliforme, a gram-negative and obligate intracellular bacterium. The disease occurs in multiple species. A triad of lesions, namely colitis, hepatitis, and myocarditis, is described in cases of TD in some species, such as rats and mice. We carried out a retrospective analysis of 25 equine cases with a diagnosis of TD; 24 of 25 cases occurred in foals <45 d old; the remaining foal was 90 d old. There were 12 males and 12 females; no sex information was available for one foal. The affected breeds were Quarter Horse, Thoroughbred, Arabian, Paint, and...
Rickets in a Thoroughbred-cross foal: case report and review of the literature. Rickets is a metabolic bone disease associated with failure of endochondral ossification and impaired osteoid mineralization in growing animals. As a consequence, affected individuals can develop gross and microscopic bone malformations. The most common causes of rickets in domestic species include vitamin D and phosphorus deficiency. Rickets has been described in multiple species; however, comprehensive postmortem characterizations with confirmatory histopathology in equids have not been published. A 6-mo-old, Thoroughbred-cross foal was diagnosed with rickets based on gross autopsy findings ...
Streptococcus pluranimalium meningoencephalitis in a horse. A 3-y-old, female Quarter Horse with a history of acute neurologic signs was found dead and was submitted for postmortem examination. Areas of petechial and ecchymotic hemorrhage were present on cross-sections of the cerebrum, cerebellum, and brainstem. Histologic examination of the brain revealed severe, purulent meningoencephalitis and vasculitis with a myriad of intralesional gram-positive cocci. was identified from formalin-fixed, paraffin-embedded tissue obtained from sites with active lesions by PCR and nucleotide sequencing of bacterial 16S ribosomal RNA. should be considered as a cau...
Feasibility of using tissue autolysis to estimate the postmortem interval in horses. Estimation of the postmortem interval (PMI) is a poorly studied field in veterinary pathology. The development of field-applicable methods is needed given that animal cruelty investigations are increasing continually. We evaluated various histologic criteria in equine brain, liver, and muscle tissue to aid the estimation of PMI in horses, which is central to forensic investigations of suspicious death. After death, autolysis proceeds predictably, depending on environmental conditions. Currently, no field-applied methods exist that accurately estimate the PMI using histology in animals or human...
Sudden death caused by spinal cord injury associated with vertebral fractures and fetlock failure in a Thoroughbred racehorse. The most prevalent causes of death in racehorses are musculoskeletal injuries, causing ~83% of deaths within the racing industry in California and elsewhere. The vast majority of these injuries have preexisting lesions that predispose to fatal injury. A 4-y-old Thoroughbred colt suffered an acute suspensory apparatus failure, including biaxial proximal sesamoid bone fractures of the right front fetlock, causing loss of support of the fetlock joint and consequent fall with fractures of the cervical and sacral spine. Cervical fracture caused spinal cord damage that resulted in sudden death. A pr...
Evaluation of 2 ELISAs to determine Borrelia burgdorferi seropositivity in horses over a 12-month period. The blacklegged tick (), which transmits , the causative agent of Lyme disease, has undergone rapid range expansion in Ontario. In horses, Lyme disease remains an enigmatic disease, with limited understanding of the pathogenesis and many issues pertaining to selection and interpretation of laboratory tests. We evaluated seropositivity in naturally exposed horses over a 12-mo period and compared paired samples with 2 common serologic tests. Serum samples were collected in 2017, ~1 y after initial testing, from a cohort of 22 horses that were seropositive in a 2016 seroprevalence study. Sampl...
Simultaneous quantification of vitamin E and vitamin E metabolites in equine plasma and serum using LC-MS/MS. Vitamin E deficiencies can impact normal growth and development in humans and animals, and assessment of circulating levels of vitamin E and its metabolites may be an important endpoint for evaluation. Development of a sensitive method to detect and quantify low concentrations of vitamin E and metabolites in biological specimens allows for a proper diagnosis for patients and animals that are deficient. We developed a method to simultaneously extract, detect, and quantify the vitamin E compounds alpha-tocopherol (α-TP), gamma-tocopherol (γ-TP), alpha-tocotrienol (α-TT), and gamma-tocotrienol...
Molecular detection of equine infectious anemia virus in clinically normal, seronegative horses in an endemic area of Mexico. Equine infectious anemia (EIA) is a highly infectious disease in members of the family, caused by equine infectious anemia virus (EIAV). The disease severity ranges from subclinical to acute or chronic, and causes significant economic losses in the equine industry worldwide. Serologic tests for detection of EIAV infection have some concerns given the prolonged seroconversion time. Therefore, molecular methods are needed to improve surveillance programs for this disease. We attempted detection of EIAV in 6 clinical and 42 non-clinical horses in Nuevo Leon State, Mexico, using the agar gel immu...
Assessment of platelet biology in equine patients with systemic inflammatory response syndrome. In addition to maintaining hemostasis, platelets have an important role in modulating innate and adaptive immune responses. A low platelet count has been found to be a negative prognostic factor for survival in humans and horses with critical illnesses, such as sepsis or systemic inflammatory response syndrome (SIRS). Decreased platelet aggregation, caused by in vivo activation, has been found in human patients with severe sepsis. In our prospective controlled study, we assessed platelet biology in blood samples from 20 equine SIRS cases and 120 healthy control horses. Platelet variables such ...
Evaluation of targeted next-generation sequencing for detection of equine pathogens in clinical samples. Equine infectious disease outbreaks may have profound economic impact, resulting in losses of millions of dollars of revenue as a result of horse loss, quarantine, and cancelled events. Early and accurate diagnosis is essential to limit the spread of infectious diseases. However, laboratory detection of infectious agents, especially the simultaneous detection of multiple agents, can be challenging to the clinician and diagnostic laboratory. Next-generation sequencing (NGS), which allows millions of DNA templates to be sequenced simultaneously in a single reaction, is an ideal technology for co...
Primary sinonasal malignant melanoma with systemic metastasis in a non-gray horse. A 27-y-old Anglo-Arabian gelding with bay coat color was presented with a swelling of the left maxillary region. Fenestration on the left maxilla revealed that the left maxillary sinus was filled with black-red tissue. A portion of the tissue was excised and diagnosed histologically as malignant melanoma. Genotyping of the STX17 gene for gray coat color revealed that the horse did not have the "gray" factor. The horse was euthanized ~3 mo after first presentation. During autopsy, a black-to-gray mass extended from the left nasal cavity to the surrounding paranasal sinus and invaded the hard ...
Cumulative antibiogram and multidrug-resistant organisms in a regional equine referral hospital. Prudent use of antimicrobials is paramount to slow the development of resistance and for successful treatment. The use of cumulative antibiograms will allow evidence-based antimicrobial selection with consideration of local resistance patterns. We generated a "first-isolate-per-patient" cumulative antibiogram for a regional equine referral hospital. Bacterial organisms cultured from horses between 2011 and 2018, sample origin, antimicrobial susceptibilities, and multidrug-resistant (MDR) status were tabulated. Of 1,176 samples, 50% were culture positive. Overall, 93 of 374 (25%) were MDR. Of t...
Preanalytical variables affecting the measurement of serum paraoxonase-1 activity in horses. Paraoxonase-1 (PON-1) activity is a new inflammatory and oxidative marker. Technical effects and biological factors could affect the accuracy of PON-1 activity measurement. We investigated the effects of storage at different temperatures, repeated freeze-thaw cycles, interferences from hemolytic, lipemic, and icteric samples, and seasonal effects on PON-1 activity in horses. We evaluated 2 substrates with an automated spectrophotometer. Ten equine serum samples were stored under different conditions. Although storage at room (21°C) or refrigeration (4°C) temperature induced a statistically s...
Infectious disease surveillance of apparently healthy horses at a multi-day show using a novel nanoscale real-time PCR panel. In the United States, horses are used for a variety of purposes including recreation, exhibition, and racing. As farm, performance, and companion animals, horses are a unique species from a zoonotic disease risk perspective, and the risks of subclinical infections spreading among horses can pose challenges. Using a nanoscale real-time PCR platform, we investigated the prevalence of 14 enteric pathogens, 11 genes, and 9 respiratory pathogens in fecal samples from 97 apparently healthy horses at a multi-day horse event. In addition, sugar flotation test was performed for fecal parasites. was c...
Equine dental and skeletal fluorosis induced by well water consumption. Two horses that consumed well water with high fluoride content exhibited clinical signs of chronic dental and skeletal fluoride toxicosis and were later euthanized and autopsied. Both horses had degenerative disease of multiple joints and multiple dental defects. Elevated fluoride concentrations were found in bone and tooth samples of both horses, well water, and feed. Microscopically, abnormalities were noted in bone and tooth samples, and consisted mostly of foci of cement necrosis and hypercementosis. Horses exhibiting bilateral, highly symmetrical dental and/or skeletal lesions, with chron...
Molecular screening of XY SRY-negative sex reversal cases in horses revealed anomalies in amelogenin testing. Male-to-female sex reversal in horses is a developmental disorder in which phenotypic females have a male genetic constitution. Male-to-female sex reversal is the second most common genetic sex abnormality, after X chromosome monosomy. All male-to-female sex reversal cases studied to date have been found to be infertile. Therefore, a screening test is particularly useful in laboratories doing DNA genotyping in horses. Our laboratory has tested > 209,000 horses for parentage using a panel of microsatellite markers and the sex marker gene amelogenin (). Suspect XY sex reversal cases are rep...
Seroprevalence of Leptospira spp. in Colorado equids and association with clinical disease. Detection of is difficult as a result of intermittent leptospiruria and brief leptospiremia. Hence, diagnosis relies heavily on serologic testing, the reference method of which is the microscopic agglutination test (MAT). In horses, clinical leptospirosis has been associated with abortion, recurrent uveitis, and sporadic cases of hepatic and renal disease. Little information exists on the seroprevalence of antibodies to in equids in the United States; past nationwide studies suggest that the seroprevalence in some areas is as high as 77% (reciprocal titer ≥ 100). We tested sera from 124 ...
Sarcocystis gigantea infection associated with granulomatous eosinophilic myositis in a horse. The only species currently known to inhabit the fibers of skeletal and cardiac muscles in horses are , and . We describe herein the invasion of myofibers in a horse by , a sheep-specific species with low virulence in the original host. A hunter gelding was referred to a veterinary surgeon in Newmarket (UK). The anamnestic data reported that the horse had an initial history of swelling of the right forelimb with fluid on the front of the carpus and edema spreading up the forearm. Subsequently, 2 firm lumps were found on the left pectoral muscle adjacent to the axilla of the left forelimb. Hist...
Chronic interstitial pneumonia with features of organizing pneumonia in an adult horse. A 22-y-old American Quarter Horse gelding was presented with a history of chronic progressive respiratory problems and a diffuse pulmonary nodular pattern in thoracic radiographs. The horse was euthanized, and 4 formalin-fixed samples of lung were submitted for histopathology. There were multifocal areas of marked thickening of alveolar septa as a result of proliferation of myofibroblasts embedded in fibromyxoid matrix (interpreted as "Masson bodies"), focal areas of fibrosis, and numerous papillary projections of connective tissue into bronchioles. A diagnosis of organizing pneumonia was reac...
Seroprevalence of influenza D virus in bulls in Argentina. Influenza D virus (IDV) is considered a new agent involved in bovine respiratory disease (BRD). Based on seroprevalence studies or isolation from clinical samples, this virus has been detected on several continents and in several animal species, including cattle, pigs, camel, horses, and goats. We used an indirect in-house ELISA to detect anti-IDV antibodies in 165 serum samples from bulls on 116 farms in the province of La Pampa, Argentina. Eighty-five of 116 (73%) farms had at least 1 positive animal, and 112 of 165 (68%) of the analyzed samples were positive. There were no significant diffe...
Detection of Chlamydia species in 2 cases of equine abortion in Switzerland: a retrospective study from 2000 to 2018. Species of genus are important pathogens of animals, with a worldwide distribution and broad host range. Some species, such as , also pose a zoonotic disease risk. Abortion is one of the many diseases that has been associated with chlamydial infections in animals, with most attention focused on the economic impacts to sheep production. The role of chlamydia in equine abortions is unknown. Using the family-specific 23S ribosomal RNA (rRNA) real-time PCR, we tested 169 formalin-fixed, paraffin-embedded fetal membrane samples from 162 equine abortion cases collected between 2000 and 2018 in Swi...
A retrospective histologic study of 140 cases of clinically significant equine ocular disorders. Ocular diseases are an important category in equine medicine; however, most articles regarding histologic ocular lesions in horses are exclusive to a specific condition and do not provide a complete review of clinically significant ocular disease frequency in a diagnostic laboratory. We reviewed sections of equine eyes from 140 cases (98 enucleations [biopsies] and 42 autopsies) with clinically relevant ocular alterations at 2 diagnostic centers in the United States. The most common primary conditions were non-traumatic keratitis (36), equine recurrent uveitis (ERU; 31), traumatic injuries (22...
NetF-producing Clostridium perfringens and its associated diseases in dogs and foals. The role of type A in canine acute hemorrhagic diarrhea syndrome and foal necrotizing enteritis is poorly characterized. However, a highly significant association between the presence of novel toxigenic and these specific enteric diseases has been described. These novel toxigenic strains produce 3 novel putative toxins, which have been designated NetE, NetF, and NetG. Although not conclusively demonstrated, current evidence suggests that NetF is likely the major virulence factor in strains responsible for canine acute hemorrhagic diarrhea syndrome and foal necrotizing enteritis. NetF is a be...
Tetanus in animals. Tetanus is a neurologic disease of humans and animals characterized by spastic paralysis. Tetanus is caused by tetanus toxin (TeNT) produced by Clostridium tetani, an environmental soilborne, gram-positive, sporulating bacterium. The disease most often results from wound contamination by soil containing C. tetani spores. Horses, sheep, and humans are highly sensitive to TeNT, whereas cattle, dogs, and cats are more resistant. The diagnosis of tetanus is mainly based on the characteristic clinical signs. Identification of C. tetani at the wound site is often difficult.
Paeniclostridium (Clostridium) sordellii-associated enterocolitis in 7 horses. Enteric disease in horses may be caused by a variety of microorganisms, including several clostridial species. (previously ) has been frequently associated with gas gangrene in humans and several animal species, including horses. However, its role in enteric diseases of animals has not been fully determined. We describe herein 7 cases of enteric disease in horses associated with infection. Grossly, the small and/or large intestines were necrotic, hemorrhagic, and edematous. Microscopically, there was severe mucosal necrosis and hemorrhage of the small and/or large intestine of all horses. w...
Description of the D4/D4 genotype in Miniature horses with dwarfism. Four causative mutations (D1, D2, D3*, and D4) of chondrodysplastic dwarfism have been described in the equine () gene. Homozygotes for one of these mutations and heterozygotes for any combination of these mutations exhibit the disproportionate dwarfism phenotype. However, no case description of homozygotes for D4 (D4/D4) has been reported in the literature, to our knowledge. We report 2 Miniature horses with the genotype D4/D4 in the gene. Clinically, the 2 dwarfs had a domed head that was large compared to the rest of the body, mandibular prognathism, and short and bowed limbs, mainly in t...
Rhinosinusitis in an Australian mare caused by Flavodon flavus, a recently recognized invasive fungal pathogen of the horse. We describe herein the clinical, endoscopic, computed tomography (CT), pathologic, and microbiologic features of an infection caused by an under-recognized fungal pathogen, , in a 25-y-old Australian Quarter Horse. The horse had a unilateral obstructive nasal mass, resulting in stertor and dyspnea. On endoscopy, the mass was tan, multinodular, and completely obstructed the nasal passage. CT analysis revealed a large, soft tissue-attenuating and partially mineralized mass in the right nasal passage and dorsal-conchofrontal sinus, expanding into adjacent paranasal sinuses with associated bone ly...
Plasma adrenocorticotropic hormone concentration in horses decreases after freezing for 60 days. We investigated the stability of adrenocorticotropic hormone (ACTH) in plasma after freezing for different lengths of time. The plasma ACTH concentrations of 12 horses were measured on day 0 (baseline) and over time, after stimulation with thyrotropin-releasing hormone. Samples were stored at -80°C for 3, 7, 30, 60, and 90 d, or at -20°C for 3, 7, 30, and 60 d, or between ice packs at -20°C for 3 and 7 d prior to determination of ACTH concentration. ACTH concentrations were compared to baseline (non-frozen day 0 plasma) for each storage method using a mixed model with repeated measure...
Clostridium sordellii-associated gas gangrene in 8 horses, 1998-2019. Gas gangrene occurs in several animal species and is caused by one or more clostridial species. In horses, the disease is most often caused by Clostridium perfringens type A. Although Clostridium sordellii has been associated with gas gangrene in ruminants and humans, cases of the disease associated with this microorganism have not been described in horses, to our knowledge. We report herein 8 cases of gas gangrene caused by C. sordellii in horses. These cases were characterized by myonecrosis and cellulitis, associated with systemic changes suggestive of toxic shock. The diagnosis was confirm...
A novel PCR protocol for detection and differentiation of neuropathogenic and non-neuropathogenic equid alphaherpesvirus 1. Equid alphaherpesvirus 1 (EHV-1) infections can have a major impact on the horse industry and equine welfare by causing abortion or respiratory or neurologic disease. A single nucleotide polymorphism (A→G) in open reading frame (ORF) 30, encoding the catalytic subunit of the DNA polymerase, has been shown to be a strong predictive marker for neuropathogenicity. Given that a previously established real-time PCR (rtPCR) protocol yielded unsatisfactory results concerning determination of the EHV-1 genotype, we developed and evaluated a new conventional PCR protocol enabling identification of th...