INTRAVENOUS VATINOXAN IN MARKHORS (CAPRA FALCONERI HEPTNERi) IMMOBILIZED WITH INTRAMUSCULAR MEDETOMIDINE AND KETAMINE-A PRELIMINARY DOSESCREENING STUDY.

Medetomidine is an α-2 adrenoceptor agonist commonly combined with ketamine for immobilization of nondomestic mammals. However, it may cause some remarkable adverse effects such as bradycardia, hypertension, and hypoxemia. Vatinoxan (previously called MK-467 and L-659,066) is an α-2 adrenoceptor antagonist that affects mostly the peripheral receptors due to its minimal ability to cross the blood-brain barrier. Therefore it alleviates the peripheral cardiovascular and pulmonary effects of medetomidine while sedation is maintained. In this study, the hypothesis was that vatinoxan would dose-dependently alleviate medetomidineinduced bradycardia, hypertension, and hypoxemia when administered intravenously (IV) after medetomidine and ketamine were administered intramuscularly (IM) to markhors (Capra falconeri heptneri), without impairing the immobilization. Various doses of vatinoxan were studied. In this prospective, randomized, assessor-blinded, clinical crossover study, eight markhors were immobilized two times (16 paired immobilizations altogether) with medetomidine (80 µg/kg) and ketamine (1.5 mg/kg), according to the estimated weight, IM in the same dart. Approximately 19 min later, vatinoxan (117-297 µg/kg) or saline placebo was injected IV. Atipamezole was used as a reversal agent. Pulse and respiratory rates, indirect blood pressures, arterial oxygen saturation, and body temperature were measured and blood samples collected. In general, vatinoxan alleviated the hypertension induced by medetomidine without affecting the quality of immobilization. The dose of vatinoxan correlated significantly with the reduction in arterial blood pressure. Vatinoxan showed potential to enhance cardiovascular function in captive nondomestic small ruminants immobilized with medetomidine-ketamine.

Erysipelothrix rhusiopathiae infection in a captive white-lipped peccary (Tayassu pecari) in Finland.

Erysipelothrix rhusiopathiae is a zoonotic pathogen that causes infections in several animal species, including erysipelas in swine, lambs and turkeys. In October 2022, a captive, 1-year-old white-lipped peccary (Tayassu pecari), kept in a herd of five peccaries in a zoo in Finland, suddenly developed signs of inappetence and reluctance to move. Despite treatment, the peccary was found dead. At necropsy, the main gross finding was severe acute segmental necrotizing enteritis. Several other organs had lesions compatible with acute septicaemia, including petechiae and ecchymoses. Histopathology of the intestine revealed severe acute multifocal necrotizing enteritis with neutrophilic vasculitis, vascular fibrinoid microthrombi and myriad clusters of densely packed, rod-shaped, gram-positive bacteria on the tips of the intestinal villi. Bacterial culture was identified as E. rhusiopathiae by MALDI-TOF mass spectrometry. To our knowledge, this is the first report of a naturally occurring E. rhusiopathiae infection in a captive white-lipped peccary. Our findings suggest that regular vaccination of captive white-lipped peccaries should be taken into consideration in preventing infections due to E. rhusiopathiae.

Sarcocystis calchasi in a captive Patagonian conure (Cyanoliseus patagonus) in Finland.

Sarcosystis calchasi is an emerging pathogen causing encephalitis in many avian species and has been documented in North America, Germany and Japan. In November 2019, a captive Patagonian conure (Cyanoliseus patagonus), kept in a zoological aviary in Finland, was euthanized due to acute respiratory distress. At necropsy, histopathological examination revealed numerous parasitic tissue cysts in the skeletal muscles and myocardium, chronic moderate multifocal lymphoplasmacytic and histiocytic meningoencephalitis and acute moderate multifocal purulent pneumonia caused by aspiration of foreign material. By light and transmission electron microscopy, tissue cysts had structures typical of Sarcocystis organisms. The ultrastructure of the cyst wall was compatible with S. calchasi and Sarcocystis columbae. S. calchasi-specific semi-nested polymerase chain reaction testing resulted in amplification of the internal transcribed spacer (ITS) gene, which had 100% identity with S. calchasi ITS sequences. This is the first report of S. calchasi in Fennoscandia and of a naturally-occurring S. calchasi infection in a captive psittacine bird in Europe. Our finding suggests that captive psittacine birds kept in outdoor facilities may be at risk of S. calchasi infection throughout the Holarctic.

Viral haemorrhagic septicaemia (VHS) outbreaks in Finnish rainbow trout farms.

In Finland, viral haemorrhagic septicaemia virus (VHSV) was diagnosed for the first time in 2000 from 4 rainbow trout farms in brackish water. Since then the infection has spread and, by the end of 2004, VHSV had been isolated from 24 farms in 3 separate locations: 2 in the Baltic Sea and 1 in the Gulf of Finland. The pathogenicity of 3 of these isolates from 2 separate locations was analysed in infection experiments with rainbow trout fry. The cumulative mortalities induced by waterborne and intraperitoneal challenge were approximately 40 and 90 %, respectively. Pair-wise comparisons of the G and NV gene regions of Finnish VHSV isolates collected between 2000 and 2004 revealed that all isolates were closely related, with 99.3 to 100% nucleotide identity, which suggests the same origin of infection. Phylogenetic analysis revealed that they were closely related to the old freshwater isolates from rainbow trout in Denmark and to one old marine isolate from cod in the Baltic Sea, and that they were located close to the presumed ancestral source. As the Finnish isolates induce lower mortality than freshwater VHSV isolates in infection experiments, they could represent an intermediate stage of marine isolates evolving towards pathogenicity in rainbow trout.