2016 - 85 (5)

Since 2016, an extensive spread of RHDV2, a virus variant of the classical rabbit hemorrhagic diseasevirus (RHDV) is ongoing in the Belgian rabbit population. Both variants of the virus usually causeacute death without prior symptoms.Vaccination against both variants of the virus is possible. In Belgium, only a vaccine protectingagainst the classical RHDV has been registered. On their own responsibility, veterinarians are allowed–to import a vaccine protecting against RHDV2 that is registered in another EU member state,in accordance with the so-called legislative waterfall-system.The current epidemiological situation warrants preventive vaccination of rabbits against RHD. Itshould be noted that myxomatosis is currently rather neglected in view of the increased attention forthe RHDV2 spread. Myxomatosis also still causes a high mortality in both wild and domesticated rabbits.Veterinarians should correctly inform the public about the two important viral diseases in rabbitsand the possibilities for prevention.

In this report, clinical and histological findings of a rare case of a large congenital fibropapillomaon the forehead of a warmblood foal are reported. Surgical excision was curative and norecurrence was observed after nine months. The foal did not present any other abnormalities.Morphologically, the lesion was classified as a fibro-epithelial type of skin hamartoma. The fibrouscomponent has thus far only been reported in pigs. Although fibropapillomas are commonin adult animals and are associated with papillomavirus infection, this association has not beendemonstrated in foals and piglets. Additionally, there were no histopathological indications ofpapillomavirus infection in the present study, nor could PCR reveal the presence of papillomavirusDNA.

A ten-month-old, intact, male Cavalier King Charles spaniel was presented two months after anabdominal bite incident with inspiratory dyspnea and positional pain. A diaphragmatic herniation wassuspected, based on absent lung- and cardiac sounds on auscultation of the left hemithorax. Radiographyconfirmed this but also showed the presence of severe tympany of a herniated stomach. This is calledtension gastrothorax and is an immediate life-threatening complication of the herniation. Because ofthe progressive worsening of the cardiorespiratory condition of the patient and the inability to intubatethe stomach, immediate surgical correction was necessary. A standardized surgical approach was usedto reposition the stomach and close the hernia. There were no postoperative complications and one yearafter the surgery, the dog was still doing well.

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

Between April 2012 and July 2015, cloacal and/or tracheal swab samples were collected from fourhundred and twenty-four Belgian chicken broiler, breeder and layer flocks. All flocks were kept forproduction purposes and presented clinical signs suggestive of an infectious bronchitis virus (IBV)infection. The samples were analyzed by real-time polymerase chain reaction (RT-qPCR) to detectthe presence of ribonucleic acid (RNA) of IBV. When positive, approximately four hundred base pairs(bp) encoding for the hypervariable region of the IBV S1 protein were sequenced. Sequencing results,cycle threshold (Ct) values and vaccination history were used as criteria to try and distinguish vaccinestrains from field strains.Of all samples examined, 22.4% was negative. In 16.4% of the samples that did contain RNAfrom IBV, the genotype could not be determined. In most cases, this was due to the recovery ofRNA quantities below the lower limit of detection of the sequencing PCR. The remaining positivesubmissions predominantly revealed RNA from IBV strains that belonged to the 4/91–793B (46.8%),D388–QX (25.2%), D274-D207 (5.8%) and Massachusetts (4.0%) genotypes. Estimations indicatedthat approximately 58%, 11%, 37% and 46% of these detections, respectively, were vaccine strains.Infections with types CK/CH/Guandong/Xindadi/0903, Ukr/27/2011, NGA/295/2006 and Q1 wereobserved sporadically.The results indicate that IBV infections are highly prevalent in Belgian chickens and that at leasteight different IBV types were circulating during the monitored period. This underlines the necessityof providing flocks with a strong and broad protective immunity against IBV.

This retrospective study determined disease free survival (DFS) and progression freesurvival (PFS) in chemo-naïve dogs with multicentric or cranial mediastinal high-grade T-celllymphoma, treated with a first-line CCNU-L(-chlorambucil)-CHOP protocol. Of thirteen dogswith multicentric lymphoma, 92.3% achieved a complete remission (CR), and the median DFSand PFS was 317 and 256 days, respectively. Three dogs had cranial mediastinal lymphoma,and achieved a CR with a median DFS and PFS of 978 and 1007 days, respectively. The oneandtwo-year DFS/PFS probability estimate for dogs with multicentric lymphoma was 0.50/0.46and 0.42/0.38, respectively, for dogs with cranial mediastinal lymphoma 0.67/0.67. Neutropeniaand thrombocytopenia were reported in 52.9% and 50% of the dogs, respectively, while 56.3%experienced grade 1-4 nephrotoxicity, hypothesized to be lomustine-induced. It was concludedthat, compared to historical data, the currently described first-line CCNU-L(-chlorambucil)-CHOP protocol could benefit the survival of dogs with multicentric or cranial mediastinal highgradeT-cell lymphoma.

In the second part of this review article , the diagnostic aspects of thyroid scintigraphy arediscussed, with major emphasis on hyperthyroidism, followed by an overview of radioiodinetreatment.

In the first part of this review article, thyroid anatomy, physiology and pathophysiology arereviewed to continue more specifically on hyperthyroidism, the most common thyroid disorderin cats. The diagnostic work-up of this disorder is discussed with emphasis on thyroid glandimaging. Scintigraphy is most commonly used and best suited to assess thyroid function, whichwill be discussed extensively in the second part of this review article. All other available imagingmodalities do not offer a functional assessment and are therefore of limited use in the diagnosisand evaluation of hyperthyroidism.