Multicentric B-cell lymphoma in a pygmy goat

A six-year-old, male pygmy goat was referred with a sudden onset of peripheral lymphadenopathy, which initially started as enlarged inguinal lymph nodes. Clinical examination showed swollen retropharyngeal, prescapular and inguinal lymph nodes. Serologic testing for bovine leukemia, caprine arthritis-encephalitis virus and caseous lymphadenitis was negative. Fine needle aspirates of the prescapular lymph nodes were taken and revealed multiple, large lymphoblastic cells on cytology. Because of the poor prognosis and clinical deterioration, the animal was euthanized. Full necropsy was performed and showed generalized lymphadenopathy. Further histological and immunohistochemical investigation of the lymph nodes characterized this neoplasia as a multicentric large B-cell lymphoma.

Prevalence of respiratory pathogens in nasal swabs from horses with acute respiratory disease in Belgium

Contagious respiratory infections are an important cause of respiratory disease in horses, resulting in impaired pulmonary function, poor performance and sometimes severe illness. Although bacterial infections are often suspected to be involved, viruses are frequently overlooked and are an underestimated cause of respiratory disease outbreaks in horses. In this study, nasal swabs of 103 horses with acute symptoms of respiratory disease were analyzed for the presence of 13 different respiratory pathogens. Gamma herpesviruses were the most commonly detected, with 60% of the samples being positive, followed by streptococcus equi subsp. zooepidemicus infection (30%). Rhinovirus B, streptococcus equi subsp. equi, adenovirus 1 and EHV-4 were more rarely detected. Further research is necessary to correctly interpret the importance of gamma herpesviruses in horses, for example by screening a healthy control population. National surveillance of respiratory viruses in horses by PCR analysis on nasal swabs might be a useful, earlywarning system for viral epidemics.

Orale ivermectine-intoxicatie op een vleeskalverbedrijf

In deze casus wordt een vermoedelijk kwaadwillige, orale ivermectine-intoxicatie op een Vlaams vleeskalverbedrijf besproken. Alle 330 kalveren van twee tot vier weken oud werden in de eerste week na aankomst op het bedrijf getroffen. De symptomen waren ernstige depressie, het neerliggen in laterale of sternale positie, tremor en kopschudden. Uiteindelijk stierf 13,6% van de kalveren. De overige dieren herstelden gradueel met ondersteunende orale rehydratatietherapie over een termijn van vijf tot zeven dagen. In de kunstmelk kon een ivermectinegehalte van 35 mg/kg aangetoond worden. In het serum van drie kalveren werden ivermectinegehaltes van 0,75 mg/kg tot 1,1 mg/kg gevonden. De vermoedelijk toegediende dosering was 1,75 mg/kg lichaamsgewicht voor een gemiddeld kalf (40 kg). In deze casus wordt aangetoond dat orale toxiciteitsverschijnselen van ivermectine bij kalveren van twee tot vier weken oud kunnen optreden aan een dosis die 8,75 keer hoger is dan de geregistreerde therapeutische dosis voor subcutane toediening bij rundvee.

Health risks associated with the use of automatic milk feeders in calves

The objective of the present article was to summarize available evidence of the economic benefits and health risks associated with the use of automatic milk feeders (AMFs) in calves. Although AMFs are increasingly used in cattle production, clear evidence of their economic benefits (increased average daily gain, gradual weaning and reduced labor time) for the typical Belgian farm size and management is not available. Especially in smaller farms, where labor time is not a limiting factor, a careful economic consideration should be made. Regarding the association of AMFs with calf disease, studies have only been performed for bovine respiratory disease and confirmed an increased risk. However, since the use of AMFs is strongly related with several other risk factors (group housing at young age, large groups, age difference in a group, continuous system versus all-in/all-out), it is difficult to unequivocally identify the risk associated with AMFs alone. A group size of less than ten calves on a single drinking point, an all-in/allout grouping system and a minimum age at introduction to the automat of three weeks are recommended for farms with AMFs. To the authors’ knowledge, no scientific evidence supporting the presumed association of diarrhea and tongue ulcers with AMFs is available to date.

Gastro-intestinale Clostridium perfringens-infecties: een blijvend gevaar in de Belgische rundveehouderij

De intensivering van de moderne landbouw wordt geassocieerd met een toename van Clostridium perfringens-gerelateerde, gastro-intestinale problemen bij intensief gevoede runderen, zoals “hemorrhagic bowel disease” bij hoogproductief melkvee en enterotoxemie bij kalveren. Waar de pathogenese van hemorrhagic bowel disease nog grotendeels ongekend is, werden er de laatste jaren nieuwe inzichten in de pathogenese van enterotoxemie bekomen die een belangrijke repercussie op de aanpak van deze ziekte onder praktijkomstandigheden hebben. Ook andere clostridiumgeassocieerde maagdarminfecties, zoals “overeating disease” en neonatale clostridiose, worden regelmatig gediagnosticeerd. Overvoedering met structuurarme, eiwitrijke voeders is een overkoepelende risicofactor bij zowel HBD, enterotoxemie als overeating disease. Een goed uitgebalanceerd dieet dat zo stabiel mogelijk gehouden wordt, is dan ook het belangrijkste aandachtspunt op bedrijven die problemen hebben met clostridiose. Daarnaast dient bij jonge kalveren voldoende aandacht gegeven te worden aan een correcte en hygiënische biestverstrekking om problemen met neonatale clostridiose te vermijden.

A new predilection site of Mycoplasma bovis: Postsurgical seromas in beef cattle

Mycoplasma bovis is a highly contagious bacterium, which predominantly causes chronic pneumonia, otitis and arthritis in calves and mastitis in adult cattle. In humans, Mycoplasma species have been associated with post-surgical infections. The present study aimed to identify the bacteria associated with three outbreaks of infected seromas after caesarian section in Belgian Blue beef cattle. A total of 10 cases occurred in three herds which were in close proximity of each other and shared the same veterinary practice. M. bovis could be cultured from seroma fluid in five of the six referred animals, mostly in pure culture and was isolated from multiple chronic sites of infection (arthritis and mastitis) as well. DNA fingerprinting of the isolates targeting two insertion sequence elements suggested spread of M. bovis from chronic sites of infection (udder and joints) to the postsurgical seromas. Identical genetic profiles were demonstrated in two animals from two separate farms, suggesting spread between farms. Mortality rate in the referred animals positive for M. bovis in a seroma was 80% (4/5), despite intensive treatment. A massive increase in antimicrobial use was observed in every affected farm. These observations demonstrate involvement of mycoplasmas in outbreaks of postsurgical seromas in cattle.

Total plasma proANP increases with atrial dilatation in horses

Equine atrial natriuretic peptide (ANP) plasma concentrations are correlated with left atrial size. However, species-specific assays are lacking and the results from human assays are poorly reproducible. A new methodology called processing independent analysis (PIA) that measures the total proANP product in plasma has proven to be successful in human medicine, but has never been used in horses. The aims were to establish an equine proANP reference interval by measurement of the total proANP product using PIA and to examine the proANP concentrations in horses with atrial dilatation. Sample stability was studied by comparison of storage at -80°C and -20°C. Plasma samples were obtained from 23 healthy horses, 12 horses with moderate or severe valvular regurgitation without atrial dilatation and 42 horses with valvular regurgitation and atrial dilatation. The proANP concentration was significantly (P<0.001) higher in horses with atrial dilatation (761.4 (442.1-1859.1) pmol/l) than in healthy horses (491.6 (429.5-765.9) pmol/l; P<0.001) or horses with cardiac disease but without atrial dilatation (544.4 (457.0-677.6) pmol/l). A cut-off value (573.8 pmol/l) for detection of atrial dilatation was calculated. Sample storage at -80°C did not differ from sample storage at -20°C. The measurement of total proANP in plasma detects atrial dilatation in horses and may be useful for clinical evaluation in equine medicine.

Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015

REASONS FOR PERFORMING THE STUDY

Yellow fat disease or steatitis is characterised by a local or general inflammation of fat tissue and is occasionally found in horses. Diagnosis is challenging because of the wide range of nonspecific clinical signs.

OBJECTIVES

To describe clinical signs, treatment, outcome and ultrasonographic findings in horses with steatitis.

STUDY DESIGN

Retrospective study (January 2008 to January 2015).

METHODS

History, clinical signs, ultrasonographic findings, diagnosis, treatment and outcome were recorded.

RESULTS

Twenty cases (18 horses, 2 donkeys; 9 mares, 9 stallions, 2 geldings) were retrieved from 13,707 patient records. Mean age was 1.6 (± 0.8) years (range 1 month-3.5 years). All cases appeared between October and February except for one (August). History included dullness, recumbency, decreased appetite and weight loss. Fever, ventral oedema, stiff/painful gait and painful neck were found. Low haematocrit, low vitamin E and selenium and increased levels of creatinine kinase and particularly lactate dehydrogenase were almost consistent findings. On ultrasound, ventral oedema was found. Subperitoneal, perirenal, mesenteric, coronary and caudal mediastinal fat showed homogenously increased echogenicity. Especially the subperitoneal fat was surrounded by oedema or free fluid. Increased amounts of abdominal, thoracic and pericardial fluid were often found. Fat biopsies were taken in the neck or from the retroperitoneal fat in the ventral flank. In all horses where fat biopsy was taken (n = 13), steatitis was confirmed. Treatment consisted of selenium and vitamin E (intra-muscular injection followed by oral treatment) supplementation and anti-inflammatory treatment (dexamethasone or prednisolone parenteral or oral) for at least 1-4 weeks. Fourteen animals (70%) survived. Full recovery took about 2-6 months.

CONCLUSIONS

Yellow fat disease may be underdiagnosed because of the nonspecific clinical signs. Ultrasound was extremely helpful for making a diagnosis. Recovery was rather slow but was achieved in 70% of the animals. Ethical animal research: Research ethics committee oversight not currently required by this conference: retrospective study of clinical records. Explicit owner informed consent for inclusion of animals in this study was not stated.

SOURCE OF FUNDING

Ghent University (institutional). Competing interests: None declared.

Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015

REASONS FOR PERFORMING STUDY

Transcranial magnetic stimulation (TMS) is an electrophysiological technique used to elicit motor evoked potentials (MMEPs) to evaluate the functional integrity of the descending motor fibres in the spinal cord. Successful application of the technique was reported in horses with spinal cord compression. However, limited data are available on the correlation of TMS with histopathological changes.

OBJECTIVES

To determine sensitivity of TMS for assessing the integrity of the spinal cord in horses with compressive lesions of the spinal cord.

STUDY DESIGN

Case series.

METHODS

The study was conducted on 6 horses with spinal ataxia grade III-V/V admitted to the Faculty of Veterinary Medicine, Ghent University. The horses underwent TMS, radiography of the cervical or thoracolumbar vertebral column, and myelography (4/6). All horses were subjected to euthanasia and the spinal cord examined histopathologically.

RESULTS

In 5/6 horses MMEPs with abnormal onset latencies in both extensor carpi radialis muscles and cranial tibialis muscles were recorded, suggesting a cervical spinal cord lesion. Radiography revealed cervical vertebral malformation (4/5) with cervical vertebral canal stenosis (3/5) and tumour/osteomyelitis (1/5). In 1/6 horse MMEPs with normal onset latencies in extensor carpi radialis muscles and prolonged onset latencies in tibialis cranialis muscles were recorded, suggesting a thoracolumbar spinal cord lesion. Radiography revealed deformation of the 7th and 8th thoracic vertebrae. Myelography showed reduction in dural diameter and dorsal contrast column (4/4). Histopathological examination of the spinal cord confirmed compressive type lesions in all 6 horses with degenerative changes in the white matter of all funiculi, ballooning of myelin sheets, swollen axons, loss of axons and astroglial activation.

CONCLUSIONS

In this case series abnormal function of descending motor pathways as registered by TMS showed 100% sensitivity with the histopathological characteristics of compressive lesions in the spinal cord, but the number of horses is limited and further research is warranted. Ethical animal research: Research ethics committee oversight not currently required by this conference: the study was performed on material collected during clinical procedures. Explicit owner informed consent for participation in this study was not stated.

SOURCE OF FUNDING

Not applicable. Competing interests: None declared.

First confirmed case of bovine besnoitiosis in an imported bull in Belgium

Besnoitia besnoiti is a protozoan parasite known to cause important economic losses in the cattle industry in Africa, Asia and the Mediterranean area. In the last years, (re-) emergence of the parasite has been reported in France, Germany, Hungary and Italy with in some cases, establishment of an endemic infection. In this article, the first case of besnoitiosis in Belgium in a Blonde d’Aquitaine bull imported from the south of France is described. Additionally, a brief overview of the epidemiology of the disease is provided.

Surgical correction of pyelonephritis caused by multidrug-resistant Escherichia coli in a dairy cow

A four-year-old red Holstein Friesian cow was admitted to the clinic with fever and milk drop. Blood analysis revealed the presence of a chronic infection, and the diagnosis of pyelonephritis of the right kidney was made after repeated ultrasound examinations. The animal was treated with procaine benzylpenicillin, sulfadoxine trimethoprim, oxytetracycline and enrofloxacine but this therapy was not successful. Nephrectomy was performed after the left kidney proved to have a normal function. The removed right kidney was greatly enlarged and filled with pus. Escherichia coli was isolated from the kidney. The strain was multidrug-resistant, including resistance to aminopenicillins, streptomycin, sulfonamides and trimethoprim. The cow was treated with amoxicillin and clavulanic acid after the operation. Postoperatively, an abscess developed and a tube drain was placed during a second surgery to enable daily rinsing with a chlorhexidine solution. After a postoperative care period of two months, the animal was sent back to the farm, where it returned to an acceptable level of milk production. This case demonstrates that with basic surgical skills, a good preparation and knowledge of anatomy, nephrectomy is attainable for a first-opinion veterinarian, with an acceptable economic prognosis for the farmer.

Atypische myopathie bij het paard

Atypische myopathie (AM) is een vaak fatale weidemyopathie die snel opkomt in Europa. Uitbraken zijn meestal acuut en onverwacht en het is belangrijk dat dierenartsen en eigenaars weten hoe ze moeten omgaan met de kritieke patiënten van deze aandoening. Er zijn verschillende hypothesen beschreven omtrent de etiologie en pathogenese ervan. In deze review worden de belangrijkste hypothesen samengevat en enkele behandelingsmogelijkheden en preventieve maatregelen gesuggereerd. Op dit moment wordt gedacht dat AM ontstaat na opname van esdoornzaden. Deze zaden bevatten hypoglycine A, dat kan leiden tot multiple acyl-CoA dehydrogenasedeficiëntie (MADD). De behandeling is meestal gebaseerd op de klinische symptomen en gaat vaak niet verder dan een ondersteunende therapie. Daarom ligt de nadruk op de preventie van AM. Dit artikel is bedoeld als een praktische ondersteuning voor paardendierenartsen die te maken krijgen met AM.

Intestinal obstruction by Toxocara vitulorum in a calf

A one-month-old Belgian blue bull calf was referred to the animal hospital of the Faculty of Veterinary Medicine (UGhent) because of the sudden onset of severe colic. The animal showed intermittent recumbency, kicking to the abdomen, abdominal distension of the right quadrants, absence of feces and fluid-splashing and the presence of ping sounds on auscultation of the right side. Abdominal ultrasound showed distended, but still contractile small intestines with thickened walls. On exploratory laparotomy, a complete obstruction with adult Toxocara vitulorum extending from duodenum to mid-jejunum was diagnosed. On the punctum maximum of the obstruction, the ascarides were partially removed through an enterotomy. After vermifugation with doramectin, ascarides were found in the animal’s feces in the next days. In contrast to ascaride infections in puppies, piglets and foals, to the author’s knowledge, intestinal obstruction caused by T. vitulorum has not been described previously in calves.

Characteristics and challenges of the modern Belgian veal industry

In this paper, the modern Belgian veal industry is situated in a European context, and an overview is provided of the major past, present and future challenges for veal production. The production of white veal requires a specific diet and housing conditions to assure a controlled iron anemic state resulting in pale carcasses. In response to the increasing public concern about animal welfare, legal limits for hemoglobin (in 1990), the provision of a minimum quality of solid feed to assure ruminal health and group housing from the age of eight weeks on (in 2007), have been implemented sector-wide. The integrated structure of the sector likely made it possible to realize these radical changes at relatively short notice. Despite the pioneers role the veal industry played in the development of quality labels for food safety and all efforts made towards improved nutrition and housing, the veal production remains highly liable to public criticism on welfare issues. Nowadays, especially the intensive antimicrobial use in relation to high levels of antimicrobial resistance in commensal, pathogenic and zoonotic bacteria in veal calves is strongly criticized. The future challenge lies in the development of veal production systems, which require only few antibiotics, but safeguard animal welfare and revenue.

Assessment of two essential elements of BVDV control on selected Flemish dairy and beef farms

Bovine viral diarrhea virus (BVDV) is one of the most important viruses to cause disease in cattle worldwide. The virus is endemically present in Belgium. Clinical diagnosis of BVDV infection is difficult. Therefore, monitoring through testing is necessary to detect the presence of the virus on farms. As vaccination alone does not suffice for eradication, a combination of measures is required for successful control. Via a questionnaire, the BVDV policy on 241 selected Flemish cattle farms was investigated. This revealed some striking results. For the majority of the herds, the BVDV status was unknown (63%), and only 23% had a monitoring program in place. Furthermore, on seven out of ten (71%) BVDV-vaccinating farms, vaccination against BVDV was implemented as a strategy without knowing the actual BVDV status.

Spontaneous bleeding in a neonatal calf persistently infected with BVDV1b

A calf developed skin bleeding on the second day of its life. It was referred to the clinic onsuspicion of bovine neonatal pancytopenia (BNP). Hematology showed extreme thrombocytopenia,moderate anemia, but no leukopenia. A PCR test on a heparinized blood sample was bovine viraldiarrhea virus (BVDV) positive, as were the two BVDV antigen ELISAs performed three and tenweeks later. Non-cytopathic BVDV type 1b was isolated from the blood. Although the calf recoveredfrom hemorrhagic disease, and continued to be healthy, it was euthanized at eleven weeks of agebecause of persistent BVDV infection. On the basis of the case history, BNP could be excludedfrom the differential diagnosis. This case illustrates that hemorrhagic disease is not exclusivelyassociated with BVDV type 2 and that the clinical signs in neonatal calves infected with BVDV1bcan be identical to the clinical presentation of BNP.

Acute hemorrhagic syndrome by bracken poisoning in cattle in Belgium

In August 2007, two Belgian blue cows which had been on pasture for three months, showed highfever (41.4°C), epistaxis, melena, cutaneous bleeding, a stiff gait and red lesions on the udder. Bloodexamination revealed severe pancytopenia, and bluetongue virus serotype 8 could be demonstratedby PCR. Despite blood transfusion and supportive treatment, both animals died within 6 days afterthe initial symptoms. At necropsy, an explicit case of a blood coagulation disorder was observed.Inspection at pasture, one week later, showed the presence of numerous regenerated young fronds ofPteridium aquilinum. Whereas the stiff gait and the red lesions on the udder were likely bluetonguevirus associated, other symptoms were consistent with acute bracken poisoning (acute hemorrhagicsyndrome). The present report illustrates that also in Belgium, where the density of bracken fern isrelatively low, pastures should be carefully screened for the presence of young fronds.

Risk factors for Psoroptes ovis mange on Belgian Blue farms in Northern Belgium

The parasitic mite Psoroptes ovis causes important economic losses in Belgian Blue cattle. Because mange problems vary significantly between farms, a cross-sectional questionnaire survey and subsequent farm visits were performed to identify potential risk factors for P. ovis infections on Belgian Blue farms in Flanders, Belgium. The questionnaire was sent to 1800 beef farms to evaluate the presence and severity of psoroptic mange in the herd and to assess farm management practices, including antiparasitic treatments. Subsequently, about 10% of the farms with a completed questionnaire were visited to validate the questionnaire and to retrieve supplementary information on additional management parameters, such as barn infrastructure and climate. Associations between parasitism and putative risk factors were assessed by logistic regression. Out of 1800 contacted farms, 680 (38%) completed questionnaires were received. Data were collected from 238 barns during 66 farm visits. The questionnaire results demonstrated a high farm prevalence of mange (74%; 95% CI (70.7-77.3)) and half of the farmers declared that the problem was difficult to control. Nevertheless, in only 14% of the barns a high scratching index was recorded and in most of the sampled animals (80%) the affected body surface was less than 10%. This indicates that despite the high prevalence and the difficulty to control the infection, clinical signs were often quite moderate. Logistic regression analyses of the questionnaire and the farm visit data suggested that heavily infested farms treat more intensively against mange. On most farms mange occurred the whole year round and more problems with mange were found on farms where a higher number of animals were purchased per year. In addition, the disease was more prevalent when the animals had a lower hygiene score. This score was strongly correlated with environmental hygiene, indicating that transmission of mites from the environment to the animals should not be underestimated. Conflicting results were obtained on the effect of supplementing minerals on the occurrence of mange. In this study, temperature, light intensity and relative humidity in the barns, ventilation systems, barn infrastructure, animal stocking rate and blood mineral levels were not indicated as risk factors for mange. In conclusion, maintaining a good animal hygiene and if possible, avoiding introduction of cattle may help to control psoroptic mange in Belgian Blue cattle.