Exercise-induced Acute Abdominal Haemorrhage due to Iliopsoas Trauma in Racing Greyhounds.

Post-mortem examination of 74 racing greyhounds with sudden, unexpected death was undertaken at the Veterinary School, University of Nottingham, UK, from 2015 to 2019. These investigations revealed severe, acute haemoabdomen with extensive retroperitoneal haemorrhage and an underlying severe, unilateral iliopsoas tear in four cases (5.4%). In all four cases, unilateral trauma and haemorrhage affecting the right iliopsoas muscle was common near the caudal insertion. Despite the acute clinical event, three cases demonstrated histological evidence of previous muscle damage with muscular regeneration, fibrosis and evidence of chronic haemorrhage. To our knowledge, this is the first detailed description of exercise-induced trauma to the iliopsoas muscle leading to extensive haemoretroperitoneum and haemoabdomen with subsequent hypovolaemic shock and death in racing greyhounds.

Renal accumulation of prooxidant mineral elements and CKD in domestic cats.

Felids have a high incidence of chronic kidney disease (CKD), for which the most common renal lesion is chronic interstitial nephritis (CIN). CIN can be induced by tissue oxidative stress, which is determined by the cellular balance of pro- and anti-oxidant metabolites. Fish-flavoured foods are more often fed to cats than dogs, and such foods tend to have higher arsenic content. Arsenic is a pro-oxidant metallic element. We propose that renal accumulation of pro-oxidant elements such as arsenic and depletion of anti-oxidant elements such as zinc, underpin the high incidence of CIN in domestic cats. Total arsenic and other redox-reactive metal elements were measured in kidneys (after acid-digestion) and urine (both by inductively-coupled plasma-mass spectrometry) of domestic cats (kidneys, n = 56; urine, n = 21), domestic dogs (kidneys, n = 54; urine, n = 28) and non-domesticated Scottish Wildcats (kidneys, n = 17). Renal lesions were graded by severity of CIN. In our randomly sampled population, CIN was more prevalent in domestic cat versus domestic dog (51%, n = 32 of 62 cats; 15%, 11 of 70 dogs were positive for CIN, respectively). CIN was absent from all Scottish wildcats. Tissue and urinary (corrected for creatinine) arsenic content was higher in domestic cats, relative to domestic dogs and wildcats. Urine arsenic was higher in domestic cats and dogs with CIN. Arsenobetaine, an organic and relatively harmless species of arsenic, was the primary form of arsenic found in pet foods. In summary, the kidneys of domestic cats appear to have greater levels of pro-oxidant trace elements, as compared to dogs and wildcats. Since there was no difference in renal arsenic levels in cats with or without CIN, renal arsenic accumulation does not appear a primary driver of excess CIN in cats. Given clear differences in renal handling of pro vs. anti-oxidant minerals between cats and dogs, further in vivo balance studies are warranted. These may then inform species-specific guidelines for trace element incorporation into commercial diets.

A Fibromyxoid Stromal Response is Associated with Muscle Invasion in Canine Urothelial Carcinoma.

Canine urothelial carcinoma (UC) is the most common type of cancer of the lower urinary tract and tends to affect elderly neutered female dogs, with a high predisposition for Scottish terriers. Tumour stroma, inflammation and necrosis are poorly characterized in canine UC and their role as prognostic factors is unknown. The aims of this study were to (1) assess histologically 381 canine UCs, with emphasis on myxoid tumour stroma, inflammation and necrosis and (2) assess possible associations between these features and the available epidemiological data as well as bladder wall muscle invasion. In 103 of 381 (27%) cases, the stroma was mixed collagenous and myxoid (fibromyxoid), which was strongly associated with invasive growth of muscle (P <0.0001). Peritumoural and intratumoural inflammation was present in 308 of 345 (89%) and 287 of 381 (75%) cases, respectively, and was mostly mild and lymphoplasmacytic. One hundred and fifteen of the 381 (30%) cases showed a variable eosinophilic inflammation and 58 of 381 (15%) presented with formations of one or several lymphoid follicles. Twenty-four percent (91 of 381) of cases had tumour necrosis, which was typically mild. In 83 of 91 (91%) cases, the necrosis was comedo-like. Moderate to severe tumour necrosis was associated with the presence of moderate to predominant fibromyxoid tumour stroma (P <0.02). The results of this study indicate that fibromyxoid stroma is common in canine UC and is a strong indicator for invasive growth of muscle, which is consistent with a poor prognosis. Based on histomorphology, tumour necrosis in canine UC is best described as comedonecrosis.

Pulmonary Basaloid Squamous Cell Carcinoma in a Dog.

A 9-year-old neutered male crossbred dog with a 4-week history of progressive vestibulocerebellar signs was presented for necropsy examination. Gross examination revealed neoplastic growth in the lungs, thoracic lymph nodes, left kidney and cerebellum. Microscopically, the tumour consisted of an infiltrative, densely cellular, basaloid epithelial neoplastic growth with extensive areas of abrupt keratinization. Immunohistochemically, neoplastic cells expressed p63 and partially expressed cytokeratins 5/6. Based on these findings, the tumour was diagnosed as a primary pulmonary basaloid squamous cell carcinoma (BSSC) with metastasis to regional lymph nodes, kidney and brain. As far as the authors are aware, this is the first description of BSCC in an animal species.

Six-Year Follow-up of Slaughterhouse Surveillance (2008-2013): The Catalan Slaughterhouse Support Network (SESC).

Meat inspection has the ultimate objective of declaring the meat and offal obtained from carcasses of slaughtered animals fit or unfit for human consumption. This safeguards the health of consumers by ensuring that the food coming from these establishments poses no risk to public health. Concomitantly, it contributes to animal disease surveillance. The Catalan Public Health Protection Agency (Generalitat de Catalunya) identified the need to provide its meat inspectors with a support structure to improve diagnostic capacity: the Slaughterhouse Support Network (SESC). The main goal of the SESC was to offer continuing education to meat inspectors to improve the diagnostic capacity for lesions observed in slaughterhouses. With this aim, a web-based application was designed that allowed meat inspectors to submit their inquiries, images of the lesions, and samples for laboratory analysis. This commentary reviews the cases from the first 6 years of SESC operation (2008-2013). The program not only provides continuing education to inspectors but also contributes to the collection of useful information on animal health and welfare. Therefore, SESC complements animal disease surveillance programs, such as those for tuberculosis, bovine cysticercosis, and porcine trichinellosis, and is a powerful tool for early detection of emerging animal diseases and zoonoses.

A case of feline gastrointestinal eosinophilic sclerosing fibroplasia associated with phycomycetes.

Feline gastrointestinal eosinophilic sclerosing fibroplasia (FGESF) is a recently described inflammatory condition of domestic cats with unknown aetiology. A proportion of cases of FGESF are associated with bacteria, but antibiotic treatment is ineffective. It has been hypothesized that genetically predisposed cats may develop FGESF in response to the introduction of bacteria or other antigens into the intestinal wall. A 9- month-old male Persian cat presented with a history of marked acute haematemesis. A mass (10 cm diameter) was detected within the pylorus and proximal duodenum and this was not surgically accessible. On necropsy examination the duodenal wall was seen to be markedly thickened with extensive mucosal ulceration. Microscopically, there were haphazardly oriented trabecular bands of dense eosinophilic collagen, separated by wide, clear areas containing variable numbers of fibroblasts, eosinophils, mast cells, neutrophils, macrophages, lymphocytes and plasma cells. Numerous pleomorphic, non-parallel walled, sparsely septate hyphae, characteristic of phycomycetes, were present within the collagen matrix. Colonies of gram-positive and gram-negative rods were also present within the lesion. This is the first description of FGESF with intralesional fungi.

Detection of porcine circovirus type 2 and viral replication by in situ hybridization in primary lymphoid organs from naturally and experimentally infected pigs.

Porcine circovirus type 2 (PCV2) infection is the cause of postweaning multisystemic wasting syndrome (PMWS). It has been speculated whether cell types permissive of replication are found in the primary lymphoid organs and whether infection of these tissues has an important role in the pathogenesis of PMWS. The aim of this study was to determine if primary lymphoid organ cells support viral replication during PCV2 infection. This was done by histopathological examination of thymus and bone marrow from pigs experimentally inoculated with PCV2 (n = 24), mock-infected pigs (n = 12), pigs naturally affected by PMWS (n = 33), and age-matched healthy control animals (n = 29). In situ hybridization (ISH) techniques were used to detect PCV2 nucleic acid irrespective of replicative status (complementary probe, CP) or to detect only the replicative form of the virus (replicative form probe, RFP). PCV2 was not detected in the experimentally PCV2-inoculated pigs or the control animals. Among the PMWS-affected pigs, 19 of 20 (95%) thymuses were positive for PCV2 by CP ISH, and 7 of 19 (37%) of these also supported viral replication. By CP ISH, PCV2 was detected in 16 of 33 (48%) bone marrow samples, and 5 of 16 (31%) of these also supported replication. The 2 ISH probes labeled the same cell types, which were histiocytes in both organs and lymphocytes in thymus. The RFP labeled fewer cells than the CP. Thus, PCV2 nucleic acids and replication were found in bone marrow and thymus of PMWS-affected pigs, but there was no evidence that primary lymphoid organ cells are major supporters of PCV2 replication.

Lingual osteoma in a dog.

An 11-year-old male Belgian shepherd dog was evaluated for a one-week history of progressive lethargy, decreased appetite and excessive panting. On physical examination, a pedunculated mass protruding from the right side of the tongue base was observed. The mass was solid, irregular and multi-lobulated, and it measured approximately 4 × 2 cm. The mass was surgically excised. The histological examination was consistent with a lingual osteoma and the margins were free of neoplastic cells. The dog was euthanased eight months after the diagnosis because of an unrelated problem and no evidence of recurrence at the surgical site was appreciated at that time. To the author's knowledge, this is the first report of a lingual osteoma in a dog, and, therefore, it should be included in the differential diagnosis of masses on the tongue, especially pedunculated masses located at the base of the tongue.

Dynamics of Torque teno sus virus 1 (TTSuV1) and 2 (TTSuV2) DNA loads in serum of healthy and postweaning multisystemic wasting syndrome (PMWS) affected pigs.

Torque teno viruses (TTVs) are vertebrate infecting, small viruses with circular single stranded DNA, classified in the Anelloviridae family. In pigs, two different TTV species have been described so far, Torque teno sus virus 1 (TTSuV1) and 2 (TTSuV2). TTSuVs have lately been linked to postweaning multisystemic wasting syndrome (PMWS). In the present study, TTSuV1 and TTSuV2 prevalence and DNA loads in longitudinally collected serum samples of healthy and PMWS affected pigs from Spanish conventional, multi-site farms were analyzed. Serum samples were taken at 1, 3, 7, 11 and around 15 weeks of age (age of PMWS outbreak) and viral DNA loads determined by quantitative PCR. For both TTSuV species, percentage of viremic pigs increased progressively over time, with the highest prevalence in animals of about 15 weeks of age. TTSuV1 and TTSuV2 viral DNA loads in healthy and TTSuV1 loads in PMWS affected animals increased until 11 weeks of age declining afterwards. On the contrary, TTSuV2 DNA loads in PMWS affected pigs increased throughout the sampling period. It seems that TTSuV species differ in the in vivo infection dynamics in PMWS affected animals.

Characterization of necrotizing lymphadenitis associated with porcine circovirus type 2 infection.

Necrotizing lymphadenitis is observed in approximately 2% of pigs affected by post-weaning multisystemic wasting syndrome (PMWS). The pathogenesis of the lesion has been linked to apoptosis induced by porcine circovirus type 2 (PCV2). The aim of the present study was to gain further insights into PCV2-associated lymphoid necrosis in pigs with PMWS. Three groups of animals were studied: (1) PMWS-affected pigs with necrotizing lymphadenitis (n=5), (2) PMWS-affected pigs without necrotizing lymphadenitis (n=5) and (3) healthy pigs with no PMWS-related lesions (n=5). Investigations performed included immunohistochemical evaluation of the expression of cleaved caspase-3 and von Willebrand factor, Mallory's staining for fibrin and in-situ hybridization for detection of the PCV2 genome. The results of the study suggested that lymphoid necrosis in PMWS-affected pigs may be related to hypertrophy and hyperplasia of high endothelial venules (HEVs). The mechanism underlying these changes in HEVs was not clearly defined, but necrotizing lymphadenitis in pigs with PMWS may develop following vascular damage with thrombosis and subsequent follicular necrosis. Apoptosis was not found to be involved in lymphocyte depletion in PMWS or in PMWS-associated necrotizing lymphadenitis.

Longitudinal serological and virological study on porcine torovirus (PToV) in piglets from Spanish farms.

A study was performed to evaluate porcine torovirus (PToV) seroprevalence and infection in three multi-site farms from the North-eastern region of Spain. Serum samples from 120 piglets and faecal samples from 36 piglets were longitudinally collected at 1, 3, 7, 11 and 15 weeks of age. Serum samples from their dams (n=30) were also taken 1-week post-farrowing. PToV antibodies in serum were monitored by ELISA, while viral infection was assessed by real-time RT-PCR in faeces. A high seroprevalence (about 100%) was observed in animals older than 11 weeks and in adult sows. Moreover, all 1-week-old animals were seropositive, indicating maternal antibody transference through colostrum. The antibody titers declined to close to or below the ELISA cut-off value by the age of weaning (3 weeks of age). Development of a significant antibody response to PToV occurred before 7 weeks of age in about 50% of piglets, and the remaining animals developed the response by weeks 11 or 15. These results indicate that PToV infection occurred soon after weaning. Although the prevalence of infection in suckling piglets varied among the studied farms, PToV prevalences in 7 and 11-week-old pigs were between 50-67% and 58-75%, respectively, in all farms. Sequencing results indicated that more than one PToV strains were circulating in the studied farms. Present data suggest that PToV was endemic on the studied farms, and provide new insights on the epidemiology of PToV.

Detection of porcine torovirus by real time RT-PCR in piglets from a Spanish farm.

Toroviruses are enteric viruses belonging to the Nidovirales order that infect different animal species and humans. The lack of "in vitro" culture systems for toroviruses, except for the prototype Berne virus or BEV, isolated originally from an infected horse, has hampered their study and the development of diagnostic assays. This report describes a real time RT-PCR method to detect porcine torovirus (PToV) RNA in clinical fecal samples using primers corresponding to the gene coding for the nucleocapsid protein which are conserved in all PToV strains known to date. This method can be used to determine viral loads allowing quantitation within a range between 10(1) and 10(8) genomic units per reaction tube. The assay was evaluated with 48 rectal swabs from piglets from a Spanish farm. Nineteen out of 48 animals were shedding virus at the time of sample collection, indicating a high incidence of PToV infection in this farm. This is the first report showing the presence of PToV in Spain. The real time RT-PCR assay described in this report provides a rapid, highly sensitive, specific and reliable detection and quantitation method enabling future PToV epidemiological studies.

Swine torque teno virus (TTV) infection and excretion dynamics in conventional pig farms.

Torque teno virus (TTV) is a non-enveloped, single-stranded DNA (ssDNA) virus infecting human and non-primate species. Two genogroups of TTV (TTV1 and TTV2) have been described in swine so far. In the present study, TTV1 and TTV2 prevalences in serum, and nasal as well as rectal swabs of 55 randomly selected piglets from seven Spanish multi-site farms, were monitored from 1 to 15 weeks of age. Also, blood from their dams (n=41) were taken at 1 week post-farrowing. Samples were tested by means of two TTV genogroup specific PCRs. Although prevalence of TTV1 and TTV2 in sows was relatively high (54% and 32%, respectively), it was not directly associated to their prevalence in the offspring. Percentage of viremic pigs for both TTV genogroups followed similar dynamics, increasing progressively over time, with the highest rate of detection at 11 weeks of age for TTV1 and at 15 weeks for TTV2. Forty-two (76%) and 33 (60%) of the 55 studied pigs were TTV1 and TTV2 PCR positive in serum, respectively, in more than one sampling time. TTV1 and TTV2 viremia lasted in a number of animals up to 15 and 8 weeks, respectively. Co-infection with both TTV genogroups in serum was detected at all sampling points, but at 1 week of age. On the contrary, there were animals PCR negative to both genogroups in serum at all sampling times but at 15 weeks of age. During the study period, TTV1 and TTV2 nasal shedding increased also over time and faecal excretion was intermittent and of low percentage (<20%). In conclusion, the present study describes for the first time the infection dynamics of TTV1 and TTV2 as well as the nasal and faecal excretion throughout the life of pigs from conventional, multi-site farms. Moreover, results indicate that both swine TTV genogroups are able to establish persistent infections in a number of pigs.

Pig-major acute phase protein and haptoglobin serum concentrations correlate with PCV2 viremia and the clinical course of postweaning multisystemic wasting syndrome.

The aim of the present longitudinal study was to assess the evolution of two acute phase proteins (APPs), pig-major acute phase protein (pig-MAP) and haptoglobin (HPT), in serum from pigs that developed postweaning multisystemic wasting syndrome (PMWS) in comparison to healthy and wasted non-PMWS affected pigs. In addition, evidence of infection with other pathogens and its relation with variations in APPs concentrations was also assessed. Fourteen independent batches of 100-154 pigs were monitored from birth to PMWS outbreak occurrence in 11 PMWS affected farms. Pigs displaying PMWS-like signs and age-matched healthy controls were euthanized during the clinical outbreak. PMWS was diagnosed according to internationally accepted criteria and pigs were classified as: (i) PMWS cases, (ii) wasted non-PMWS cases and (iii) healthy pigs. At the moment of PMWS occurrence, pig-MAP and HPT concentration in PMWS affected pigs were higher than in healthy ones (p<0.0001). No differences in APPs serum concentrations between subclinically PCV2-infected pigs and healthy non-PCV2-infected pigs (based on quantitative PCR on serum results) were detected. Results showed a significant correlation between PCV2 loads and both pig-MAP (R=0.487-0.602, p<0.0001) and HPT (R=0.326-0.550, p<0.05-0.0001) concentrations in serum of PMWS affected pigs, indicating that the acute phase response in PMWS affected pigs occurred concomitantly to PCV2 viremia. No other pathogen, apart from PCV2, was consistently related with variations in APPs concentrations. A ROC analysis, made to determine the capacity of discrimination of both APPs between PMWS affected and non-affected pigs, showed higher sensitivity and specificity values using pig-MAP compared to HPT. These results suggest that pig-MAP might be a better indicator of PMWS status than HPT. Moreover, the fact that APR occurred some weeks before the start of clinical signs suggests that APPs could provide valuable prognostic information for PMWS development.

Torque teno virus (TTV) infection in sows and suckling piglets.

Torque teno virus (TTV) is a single-stranded DNA virus that has been detected in serum of primate and non-primate species including swine. Little information on swine TTV infection and transmission dynamics is nowadays available. The goal of this study was to gain insight into the potential role of the sow in transmitting TTV to piglets and the infection dynamics of both swine TTV genogroups (TTV1 and TTV2) during the lactation period. Serum samples from 44 sows at 1-week post-farrowing and 215 piglets at 1 and 3 weeks of age were tested using TTV1 and TTV2 PCR methods. Sow parity distribution and the number of delivered piglets (liveborn, stillborn and mummified) per each studied sow were recorded. TTV1 was detected in higher percentages than TTV2 in both sows (75% vs. 43%, respectively) and piglets at 1 (17% vs. 7%, respectively) and 3 (32% vs. 12%, respectively) weeks of age. TTV1 and TTV2 co-infections were observed in higher percentages in sows (34%) than in piglets (2% and 4% at 1 and 3 weeks of age, respectively). Detection of swine TTV genogroups in sows was not associated with their detection in piglets. Moreover, there were piglets infected at 1 week of age with a swine TTV genogroup different from the one detected in their dam. The number of sows delivering stillborns and the mean number of stillborns per sow tended to be higher in the TTV2 infected sows; this value was significantly higher when co-infected sows (TTV1 and TTV2) were compared with non-co-infected ones. Old parity sows had a higher percentage of TTV1 infected 1-week-old piglets. Results of the present study showed that the TTV infection occurs early in the production system and that these viruses may be transmitted from sow-to-piglet but also from piglet-to-piglet in farrowing facilities.

Inter-laboratory and inter-assay comparison on two real-time PCR techniques for quantification of PCV2 nucleic acid extracted from field samples.

Several real-time PCR assays for quantification of PCV2 DNA (qPCR) have been described in the literature, and different in-house assays are being used by laboratories around the world. A general threshold of 10(7) copies of PCV2 per millilitre serum for postweaning multisystemic wasting syndrome (PMWS) diagnosis has been suggested. However, neither inter-laboratory nor inter-assay comparisons have been published so far. In the present study, two different qPCR probe assays used routinely in two laboratories were compared on DNA extracted from serum, nasal and rectal swabs. Results showed a significant linear association between the assays (p<0.0001), and a systematic difference of 1.4 log10 copies of PCV2 per millilitre of sample (p<0.0001). This difference indicated that the assay from laboratory 1 yielded a higher output than the one from laboratory 2. Results also showed that there was no linear association between the amount of PCV2 DNA and the amount of total DNA, neither in nasal (p=0.86) nor in rectal (p=0.78) swabs, suggesting that normalizing of PCV2 DNA load in swab samples to total DNA concentration is not suitable. The present exploratory study highlights the need for the performance of ring trials on qPCV2 protocols between laboratories. Meanwhile, the proposed thresholds for PMWS diagnosis should only be considered reliable for each particular laboratory and each particular assay.