Spontaneous mammary neoplasms are uncommon in nonhuman primates (NHPs), particularly in neotropical species, and their pathologic aspects and biological behavior remain poorly characterized. Here, we describe the pathology and immunohistochemical features of spontaneous metastatic mammary carcinomas in 2 elderly captive capuchin monkeys (Sapajus libidinosus). A 26-y-old female and a 29-y-old male had unilateral mammary masses and died as a result of complications associated with advanced neoplastic disease. Grossly, both tumors had marked local invasion and systemic metastases involving lymph nodes, lungs, liver, and pericardium. Histologically, both carcinomas were poorly demarcated, infiltrative malignant epithelial proliferations arranged predominantly in solid nests and trabeculae, with central necrosis, marked anisocytosis and anisokaryosis, high mitotic activity, and vascular invasion. Immunohistochemically, both tumors expressed pancytokeratin, CK7, mammaglobin, HER2, and Ki67. The female had a triple-positive phenotype (ER+, PR+, HER2 2+), whereas the male had an HER2-enriched profile (ER low or negative, PR-, HER2 3+). Ki67 indices were high in both cases (31% and 35%, respectively), supporting elevated proliferative activity. The immunophenotypic and pathology findings resembled aggressive high-grade human breast carcinomas associated with poor prognosis and metastatic potential. A literature review confirmed the rarity of spontaneous mammary tumors in neotropical NHPs and highlighted the scarcity of cases with metastases. Collectively, our findings expand the current knowledge of mammary neoplasia in NHPs and reinforce the comparative relevance of these species for understanding similar human breast cancer.
An 8-mo-old Japanese Black beef heifer calf was presented with anorexia, dysuria, and abdominal pain. Ultrasonographically, the left renal pelvis and calyces were markedly dilated and contained numerous calculi; the right renal pelvis was filled with hyperechoic material without obvious calculi. Despite supportive care and antimicrobial treatment with ceftiofur, the calf died 4 d after presentation. Autopsy revealed severe hydronephrosis with numerous struvite calculi in the left kidney and advanced pyonephrosis in the right kidney. Proteus mirabilis was isolated antemortem from urine and postmortem from purulent material in both kidneys, ureters, urinary bladder, and an associated urachal remnant abscess. As found in our case, P. mirabilis infection in cattle can be associated with both obstructive and suppurative renal lesions within a single animal. Our case emphasizes the importance of comprehensive diagnostic investigation, including bilateral renal ultrasonography and thorough bacteriologic evaluation, and offers diagnostic insight into the variable pathologic manifestations of P. mirabilis-associated urinary tract disease in cattle.
The BC-75R Vet (Mindray Animal Medical) is a multi-species hematology analyzer that uses electrical impedance and SF-Cube technology (combining laser scatter, fluorescence, and 3-dimensional analysis) for CBC and reticulocyte analysis. We evaluated its analytical performance and compared it with the Advia 2120i (Siemens), a widely used analyzer in veterinary clinical pathology. CBCs were performed on EDTA-anticoagulated blood samples from 411 dogs and 225 cats submitted for routine testing. Analytical precision, linearity, carryover, and total observed error (TEobs) were assessed according to ASVCP guidelines. We used a 2120i as the reference method and manual differential counts for WBC evaluation. RIs were calculated from 131 healthy dogs and 53 cats. The BC-75R Vet fulfilled the ASVCP requirements for repeatability (CVs < 5% for most variables) and linearity (r > 0.97), with negligible carryover. TEobs values were within ASVCP allowable error limits, except for WBC types in QC material, which remained acceptable for in-clinic use. Agreement with the 2120i was acceptable for most RBC-related variables; however, systematic and proportional errors were found for mean corpuscular hemoglobin concentration (MCHC) in both species, and a systematic error for mean corpuscular volume (MCV) was found in dogs. Agreement for WBC and platelet counts was generally good, although discrepancies were noted for monocyte and mean platelet volume in both species. These differences likely reflect methodologic differences and known challenges in feline hematology. Despite these limitations, the BC-75R Vet met ASVCP standards and appears suitable for routine testing in dogs and cats. Manual smear review remains essential in selected cases.
Canine distemper virus (CDV; family Paramyxoviridae , taxon species Morbillivirus canis ) causes systemic disease in a broad range of mammalian hosts. CDV commonly targets epithelial, lymphoid, and nervous tissues. Reproductive disease is reported less frequently. Here, we describe CDV-associated placentitis and abortion in a 4-y-old, female Linnaeus’s two-toed sloth ( Choloepus didactylus ) from a private collection. The animal developed respiratory and gastrointestinal illness, aborted a midgestational fetus, and subsequently died. Gross examination revealed necrotizing placentitis. Histologically, the uterus and placenta had vasculitis with thrombosis, endothelial syncytia, and intracytoplasmic and intranuclear viral inclusions within endothelial cells. Additional maternal lesions included bronchointerstitial pneumonia, lymphoid depletion, hepatic necrosis, multisystemic intracytoplasmic and intranuclear viral inclusions, and secondary fungal infection. CDV antigen was abundant within endothelial cells, vessel walls, and perivascular stroma in the uterus and placenta by immunohistochemistry. Real-time PCR detected CDV in the maternal uterus, lung, and placenta. The hemagglutinin gene shared 98.3% nucleotide sequence identity with a CDV previously detected in a raccoon in the United States. Our case documents CDV-associated reproductive failure and endothelial tropism in a sloth, highlighting the potential for severe disease in captive nontraditional hosts.
A 3-y-old rooster was submitted for postmortem evaluation following a 4-mo history of progressive ulcerative dermatitis affecting the right hock. Autopsy revealed 6 bilateral, discrete globoid masses along the caudoventral cervical musculature and extending into the proximal celomic cavity. Histologically, a neoplasm effaced and/or compressed residual thymic parenchyma and consisted of ill-defined aggregates of 2-3 primordial germ cell lineages (ectoderm, mesoderm, endoderm). Immunohistochemical and histochemical stains, including desmin, glial fibrillary acidic protein, pancytokeratin, and phosphotungstic acid hematoxylin, confirmed the presence of heterogeneous germ cell tissues, consistent with an extragonadal teratoma. Extragonadal teratomas are rare in non-human species, particularly in avian species, and reports of mediastinal involvement are limited. In our case, the teratoma was an incidental finding; the primary reason for submission was progressive necroulcerative bacterial dermatitis affecting the right leg.
Canine extramedullary plasma cell tumors (cePCTs) are common integumentary round-cell tumors. The presence of adipocytes among round cells, which is thought to be the result of trapping of subcutaneous adipocytes, is reported as a helpful diagnostic feature to distinguish cePCTs from other round-cell tumors in the skin. Here, we report our retrospective analysis of the prevalence, extent, and distribution of adipocytes in cePCTs from a single institution. We found adipocytes in 73 of 265 (27.5%) cePCT cases diagnosed from 2020-2024, suggesting that intra-tumoral adipocytes are a frequent histologic feature in cutaneous cePCTs. We found that 1-96% of the mass was composed of adipocytes, as quantified on whole-slide images. Of the cePCTs with adipocytes, 27 (37%) cases did not have significant involvement of the subcutis. Adipocyte-containing cePCTs were more frequent in our case series than were amyloid-producing cePCTs (19; 7%). A subset of 9 cases had limited involvement of the subcutis. The proportion of intra-tumoral adipocytes was far greater (>10%) than would be expected for simple entrapment of subcutaneous adipocytes, suggesting the promotion of proliferation of mature adipocytes by neoplastic cells.
Bovine alphaherpesvirus 1 (BoAHV1; family Orthoherpesviridae, taxon species Varicellovirus bovinealpha1)-a major cause of reproductive losses in cattle-establishes lifelong latency with periodic reactivation. Although vaccination reduces disease severity and abortion risk, BoAHV1 continues to circulate in cattle populations. Here, we report the whole-genome sequencing (WGS) of a BoAHV1 isolate recovered from fetal tissues associated with a last-trimester abortion in a vaccinated heifer herd. BoAHV1 was confirmed by quantitative PCR (qPCR) and virus isolation in Madin-Darby bovine kidney cells. The cell culture-isolated virus was subsequently sequenced using an Oxford Nanopore platform. Comparative genomic analysis using reference strain MH791339 identified 73 nucleotide variants (~0.12% of the genome), mostly located in the unique short (US) region. Multiple high-impact frameshift mutations were detected in several viral genes, including independent frameshifts in the infective cell protein 4 gene (bICP4) and moderate-impact variants in US3, a gene involved in immune modulation. Overall, genomic features were consistent with a wild-type BoAHV1.1 field strain and not compatible with known modified-live virus vaccine genomes. Our findings highlight the extent of genomic variability of BoAHV1 circulating in vaccinated cattle populations and demonstrate the value of WGS for resolving diagnostic questions related to abortion events and vaccine strain exclusion.
An 8-y-old, castrated male Korean Shorthair cat was presented to a veterinary clinic for evaluation of a cutaneous mass on the left inner thigh. Microscopic examination revealed a poorly circumscribed dermal neoplasm composed of poorly granulated, pleomorphic neoplastic mast cells with frequent cell-in-cell structures. Notably, viable neoplastic mast cells were engulfed by large macrophages, indicating a specific form of the cell-in-cell phenomenon. Immunohistochemistry for c-KIT, IBA1, and cleaved caspase-3 was used to support the diagnosis. To our knowledge, cell-in-cell phenomenon has not been previously described in feline cutaneous mast cell tumors, nor has the clinical outcome of such cases been reported.
Bovine leukemia virus (BLV; family Retroviridae, taxon species Deltaretrovirus bovleu) infection poses a serious threat to cattle health, and the strategic identification of high proviral-load (PVL) carriers is essential for disease control. We evaluated 2 commercial ELISA kits for the detection of BLV antibodies and indirect identification of high-PVL cattle (EBL ELISA [Nippon Gene] and Leukosis Serum X2 [Idexx]) using a cross-sectional survey of 155 cattle from 17 farms. Based on our quantitative real-time PCR (qPCR) results, we classified tested cattle into non-infected, low-PVL (<400 copies/10 ng DNA), and high-PVL (≥400 copies/10 ng DNA) groups. The 2 ELISA kits had excellent agreement (κ = 0.97; 95% CI [0.93, 1.00]) and moderate correlation (r = 0.617). In a receiver operating characteristic curve analysis, the Leukosis Serum X2 ELISA performed better than the EBL ELISA at identifying high-PVL cattle, with a higher area under the curve (0.840 vs. 0.785) and higher sensitivity (89.7% vs. 84.6%) and specificity (66.4% vs. 56.9%). Both ELISA kits had a moderate ability to distinguish high-level BLV-infected cattle. Our results suggest that a 2-step screening concept could be valuable: ELISA screening followed by confirmatory qPCR testing to identify cattle with a high PVL.
Bovine rotavirus A is a major cause of neonatal calf diarrhea and can lead to significant economic losses for cattle producers. Studying genotypic diversity among circulating RVA strains is critical to understanding virus epidemiology and to enhancing vaccine development. We identified 1,515 fecal samples from calves with enteric disease. Samples originated from 9 U.S. states and were submitted to the Nebraska Veterinary Diagnostic Center between 2020-2025 for bovine rotavirus A (RVA) testing. Of these 1,515 samples, 540 tested positive by reverse-transcription quantitative real-time PCR (RT-qPCR), and 76 were genotyped. Among VP7 (G-type) and VP4 (P-type) genes, G6P[5] were most frequent (36 of 76), followed by G10P[11] (12 of 76) and G6P[11] (7 of 76); 15 samples were partially genotyped. Five isolates (3 G8P[1] and 2 G6P[5] strains) were cultured in MA-104 cells and sequenced using long-read nanopore technology. In phylogenetic analysis, all isolates clustered within established bovine RVA genotype lineages and included both closely related strains and distinct sub-lineages. Our descriptive findings indicate that a diverse set of viruses circulates in U.S. cattle, and we offer sequence data for comparison with previously reported strains.
Here, we describe and characterize catastrophic pelvic fractures in Thoroughbred racehorses in California. We reviewed retrospectively racehorse autopsy reports from horses that died spontaneously or were euthanized because of complete pelvic fractures in California between 1992 and 2018. The exercise history of affected horses was compared with eventmatched control horses. Catastrophic pelvic fractures were sustained by 133 horses. Pelvic fractures were 2.7% of all musculoskeletal fatalities. Pelvic fractures occurred during training (48.0%), racing (35.0%), and non-exercise (17.0%). Horses ≤4-y-old were affected most frequently (73.5%); horses ≥5-y-old were affected less frequently (26.5%). Fractures were more common in females (68.1%) than in geldings (23.1%) and intact males (8.8%). Bilateral fracture occurred in 46.9% of horses. The ilium was fractured alone or with other pelvic bones in 90.3% of horses; 28.4% of these cases included bilateral iliac wing fractures. Preexisting periosteal calluses associated with the catastrophic fracture line were observed in 31.9% of horses with pelvic fractures. Calluses were frequently associated with ilial fractures (88.9%). Of horses with complete pelvic fracture, 25.7% died spontaneously, and 89.6% of those deaths were a consequence of massive internal bleeding from lacerated blood vessels. The horses with pelvic fractures had fewer races (spaced farther apart), exercised less intensely throughout their career, and had more lay-ups than control horses. They also had 31% less exercise time and 40% fewer events since the last lay-up than control horses. Factors associated with these events, such as preexisting injuries, should be identified to enable recommendations for diagnosis, treatment, and prevention of catastrophic pelvic fractures.
A six-banded armadillo ( Euphractus sexcinctus ) from a zoo collection in central California developed acute neurologic signs followed by death. Postmortem examination revealed multisystemic bacterial disease (fibrinosuppurative meningoencephalomyelitis, splenitis, and endocarditis) with fibrinous necrotizing vasculitis and thrombosis. Streptococcus gallinaceus was isolated from the heart, lung, and meninges. To our knowledge, this microorganism has not been reported previously in association with systemic disease in an armadillo. Although the source of infection remains unknown, the animal was housed in the same building as chickens, a species that historically is associated with outbreaks of this bacterial infection. This case further broadens our understanding of the possible host range of S. gallinaceus and emphasizes the risk of interspecies pathogen transmission in captive environments.
During the 2020-2021 irruption year, pine siskins (Spinus pinus) experienced widespread mortality across North America, attributed to Salmonella enterica subsp. enterica serovar Typhimurium. In March 2021, 3 pine siskins were admitted to the Louisiana State University Wildlife Hospital (Baton Rouge, LA, USA) because of lethargy, respiratory distress, diarrhea, and inability to fly. All birds died on or shortly after presentation. Postmortem examination revealed necrotizing and granulomatous esophagitis (3), hepatitis (3), splenitis (2), enteritis (1), cloacitis (1), and stomatitis/rhinitis (1) with intralesional gram-negative bacilli. Immunohistochemistry revealed abundant extracellular and intracellular Salmonella sp. lipopolysaccharide antigen in affected organs. Salmonella Typhimurium was isolated from livers (3), cloacal swabs (2), and a spleen (1). One case had concurrent trichomonosis with erosive pharyngitis and necrotizing esophagitis. These cases are a subset of the larger 2020-2021 salmonellosis outbreak in passerines and are among the few reported from Louisiana.
Paratuberculosis is a chronic infectious disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). MAP is transmitted primarily through ingestion of contaminated feces, milk, or water and establishes persistent infection within intestinal macrophages by evading host immune defenses. Typical lesions include granulomatous enteritis, lymphangitis, and lymphadenitis. Lymphangitis mimicking arteritis has not been reported in bovine paratuberculosis, to our knowledge. Here, we describe a case of paratuberculosis in a 2-y-old Angus cow that was found dead. Gross changes consisted of red contents in the ileum and streaks of blood in the feces. Histologic examination revealed granulomatous enteritis with abundant intralesional acid-fast bacilli and marked inflammation of intestinal and mesenteric vessels that histologically resembled arteritis. Because arteritis is characteristic of malignant catarrhal fever (MCF), PCR testing was performed and was negative for gammaherpesvirus. MAP infection was confirmed by Ziehl-Neelsen stain and real-time PCR assay. Verhoeff-van Gieson stain revealed a complete absence of inner and outer elastic laminae, supporting a lymphatic rather than arterial origin. Endothelial cells had no immunolabeling for Prox1, a lymphatic endothelial marker, suggesting that it may not be reliably detectable in bovine tissues or that the antibody used lacks cross-reactivity with bovine Prox1. Our findings of chronic lymphangitis initially mimicked arteritis on histology. We emphasize that recognizing this phenomenon is critical to avoid misdiagnosis and highlight the limitations of Prox1 immunohistochemistry in bovine lymphatic vessels.
Free-living amebas such as Acanthamoeba spp., Balamuthia mandrillaris, and Naegleria fowleri can cause infections in humans and animals. Here, we describe 2 cases of meningoencephalitis and an outbreak of multisystemic disease caused by Acanthamoeba sp. in cattle from Central-Western Brazil. Within 3 d of onset, 2 adult cattle from 2 different herds developed acute neurologic signs, including incoordination progressing to flaccid paralysis, opisthotonos, recumbency, and spontaneous death (case 1), and blindness, behavioral alterations, and flaccid paralysis leading to euthanasia (case 2). In a separate herd, 2 of 11 calves died within 5 d of developing lethargy and incoordination and were autopsied (cases 3, 4). On gross examination, the brains of all 4 cases and the cervicothoracic spinal cord of case 3 had red-brown areas of malacia and cavitation. Case 3 also had myriad firm, white, spherical nodules in the kidneys; case 4 had numerous firm, white lung nodules. Histologically, all animals had multifocal necrosis with granulomatous inflammation and numerous amebic trophozoites and cysts in the CNS. Lesions also included pyogranulomatous pneumonia, nephritis, myocarditis, and splenitis. Immunohistochemistry and PCR, followed by sequencing, confirmed Acanthamoeba spp. infection in all 4 cases. To our knowledge, Acanthamoeba sp.-associated encephalitis and multisystemic disease have not been reported previously in cattle.
In a herd of 70 crossbred beef calves (10-12-mo-old) managed extensively in Santa Catarina, Brazil, 14 animals developed clinical signs; 9 of the 14 died within 7 d of accidental ingestion of a copper sulfate (CuSO4) product. Affected calves were lethargic, anorectic, and had green diarrhea. A bag containing remnants of blue-green product was found near the carcasses; this product was later determined to contain 53% metallic copper (Cu; dry weight). Postmortem examinations were performed on 3 calves found dead; tissue samples were collected for histopathology and mineral analysis. Gross findings included yellow-orange livers, distended gallbladders, green-blue intestinal contents, and hyperemic abomasal mucosae. Histologically, hepatic and renal necrosis varied in severity, with moderate Cu accumulation in both organs on rhodanine staining. Renal lesions were more prominent than hepatic lesions. Cu concentrations were 483 mg/kg in liver and 838 mg/kg in kidney; both were above RIs. Blood samples from 5 surviving calves were submitted for hematologic and biochemical testing; liver enzyme activities were elevated in most animals. We highlight the diagnostic value of kidney histopathology and toxicology in cases of acute copper toxicosis resulting from short-term, massive ingestion. To our knowledge, spontaneous acute CuSO4 toxicosis has not been reported previously in cattle in Brazil.
A 10-y-old American Paint Horse mare was presented to the Equine Field Services at Virginia-Maryland College of Veterinary Medicine (Blacksburg, VA, USA) for evaluation of mastitis and a possible abscess in the right mamma. Histologic evaluation of a mammary biopsy revealed a densely cellular, infiltrative neoplasm with cells arranged in packets supported by thin stroma. In a neuroendocrine immunohistochemistry panel, the neoplastic cells did not immunolabel for neuron-specific enolase or synaptophysin, positively immunolabeled for chromogranin A, and had moderate scattered immunolabeling for S100. These findings confirmed a diagnosis of mammary neuroendocrine tumor. Although the cells also did not immunolabel for cytokeratin, we cannot rule out a neuroendocrine carcinoma. Neuroendocrine mammary neoplasms are very rare and, to our knowledge, they have not been reported previously in horses. This neoplasm should be considered as a differential diagnosis for mammary tumors in mares.
We evaluated a semi-automated method for DNA extraction, expanded to herbivore feces a gyrA PCR method for the detection of Campylobacter jejuni in canine feces, added an internal positive control (IPC) DNA to specimens before DNA extraction, and multiplexed the gyrA PCR assay with the IPC assay. The addition of IPC DNA and multiplexing of the IPC assay did not affect the performance of the gyrA PCR assay. The method was repeatable with no significant difference in results across 6 d (F = 0.715; p = 0.614 with R2 = 0.818). In a single-laboratory randomized method test evaluating detection in bovine feces, sensitivity was 96.1%, specificity was 100%, and accuracy was 94.1%. In a multi-laboratory randomized method test (M-RMT) in bovine feces, agreement was 90% between laboratories on test results with κ = 0.80 (95% CI [0.64, 0.96]). Comparison of manual DNA extraction kits with a semi-automated extraction method in canine feces found 88.9% agreement, with κ = 0.78 (95% CI [0.64, 0.92]). In a second M-RMT in canine feces, accuracy was 78% with 90% agreement between the laboratories and κ = 0.80 (95% CI [0.64, 0.96]), even though inoculation of the intended fractional level was lower than intended at 45 cfu/g feces. Overall, the gyrA PCR assay was extended to an additional matrix, the inclusion of an IPC DNA and assay was successful, and the gyrA PCR assay for the detection of Campylobacter jejuni provided repeatable results in multiple laboratories.
We investigated the analytical performance and robustness of a flow-type immunosensor (FIS)-based canine C-reactive protein (CRP) measurement system against analytical interferents. To improve the clinical applicability of the canine FIS CRP measurement system, we reduced the measurement time to 9 min. Statistical analyses, including scatter plots, Bland-Altman plots, and Passing-Bablok regression analyses, were performed to evaluate agreement with a comparative method (particle-enhanced turbidimetric immunoassay). Within-run imprecision (10 replicates) was 8.2% and 6.4% at ~39 and 115 mg/L; between-run imprecision (20 measurement days) was 9.9% and 6.5% at ~39 and 115 mg/L, respectively. The lower limit of quantification in the FIS measurement system was 4.0 mg/L, and quantification linearity was confirmed from 4.0 to 300 mg/L. CRP content was measured in canine heparinized plasma samples (n = 43) using both the comparative method (x) and the FIS (y). The regression equation for our new method (y) as a function of the reference method (x) was y = 0.979x + 0.592 (R2 = 0.974). The system was robust against typical interfering components, including hemoglobin, lipids, and bilirubin. The FIS method was not suitable for K2EDTA plasma. Based on between-run imprecision (20 measurement days) and concentration-specific targeted bias derived from Passing-Bablok regression, the observed total error was 20.3% and 14.6% at ~39 and 115 mg/L, respectively, meeting the American Society for Veterinary Clinical Pathology desirable and minimum performance goals, as well as optimal performance at the higher concentration level.
Mycobacterium avium subsp. paratuberculosis (MAP) infection in deer causes paratuberculosis (PTb; Johne's disease), a slowly progressive chronic granulomatous enteritis. Accurate and rapid detection of MAP shedding by subclinical animals is essential for effective control of infection in deer herds. The VetMAX MAP 2.0 qPCR assay targeting IS900 was developed for cattle, sheep, and goats. However, the performance of the assay in sika deer (Cervus nippon) has not been evaluated. Here, we describe the use of the VetMAX MAP 2.0 qPCR assay on fecal samples from sika deer for the detection of MAP and its correlation with bacterial culture. DNA was extracted from fecal samples from 115 sika deer with known culture results (79 from a PTb-endemic herd and 36 from a PTb-free herd), using the QIAamp PowerFecal Pro DNA extraction kit. Diagnostic sensitivity and specificity were 100% (76 of 76) and 92.3% (36 of 39), respectively, with an overall accuracy of 97.4% compared with bacterial culture. A strong positive correlation was observed between culture time to detection and the qPCR Cq-value (r = 0.70, area under the curve = 0.96). Our findings offer correlation between bacterial culture and VetMAX MAP 2.0 qPCR assay results in feces of farmed sika deer and highlight the quantitative value of the qPCR assay as a rapid indicator of bacterial load and shedding intensity.
