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.

Dispersal of taeniid eggs: Experimental faecal contamination of forest environment followed by DNA detection in wild berries.

To understand Taeniidae epidemiology, the principles of egg-dispersion dynamics under natural conditions must be known. In this study, non-zoonotic Taenia laticollis was used as a model parasite for the family Taeniidae (including Echinococcus spp.). An experiment to investigate dispersion from contaminated faeces to the surroundings was performed both with bilberries (Vaccinium myrtillus) and lingonberries (Vaccinium vitis-idaea), both of which are commercially harvested wild berries in Finland. For this experiment, 30 g of fox faeces was inoculated with 30,000 T. laticollis eggs for the bilberry experiment and 100,000 eggs for the lingonberry experiment. The faecal material was placed in the middle of good berry growth areas in four locations for bilberries and eight locations for lingonberries. After 41-42 days, berries at different distances (0-15 m) from the original contamination spot were collected and delivered to our laboratory. DNA was extracted from washed and sieved material and analysed using T. laticollis-specific semi-quantitative SYBR Green real-time polymerase chain reaction (qPCR). Taenia laticollis-specific DNA was recovered from 67% (8/12) of bilberry samples but not reliably from any of the lingonberry samples 0% (0/24), although the exposure dose was higher for those. The qPCR results suggest that under natural conditions, taeniid egg dispersion from the contamination spot is demonstrated but attachment is berry specific. The surface of bilberries may be more adhesive for taeniid eggs than the waxier and harder pericarp of the lingonberries or there might be a difference in the dispersal mechanism caused by different biotopes.

Severe deforming dermatitis in a kitten caused by Caryospora bigenetica.

BACKGROUND: Caryospora bigenetica is an intracellular protozoan parasite, which in its primary hosts, typically snakes, is found it the intestine. Extraintestinal multiplication with the development of tissue cysts takes place in secondary hosts, which are normally prey for snakes. Natural infection in domestic animals has been reported only in dogs; this is the first report of C. bigenetica infection in a cat. CASE PRESENTATION: A stray kitten developed nodular dermatitis after being adopted by a shelter. Firm swelling, nodules, and crusts were present mainly on the nasal bridge, eyelids, and pinnae. Histopathology and cytology revealed severe pyogranulomatous inflammation with abundant intracellular organisms suggestive of apicomplexan protozoa. Treatment with clindamycin 13 mg/kg twice daily was initiated, but the cat was euthanized because of the worsening condition. Transmission electron microscopy confirmed parasite's apicomplexan origin postmortem, and the causative agent was identified as C. bigenetica by polymerase chain reaction and DNA sequencing. CONCLUSIONS: We present the first case of a naturally occurring infection with C. bigenetica in a cat. Although the definitive etiological diagnosis relied on molecular identification, the abundance of unsporulated oocysts and caryocysts and the parasite's effective reproduction within macrophages and in several other cell types might have enabled differentiation from other protozoal infections and allowed a presumptive diagnosis through cytology and histopathology.

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.

Clinical and Genetic Findings in 28 American Cocker Spaniels with Aural Ceruminous Gland Hyperplasia and Ectasia.

American Cocker Spaniels (ACSs) develop aural ceruminous gland hyperplasia and ectasia more often than dogs of other breeds. Data on the cause and development of these breed characteristic histopathological changes are lacking. We performed video-otoscopic examinations and dermatological work-up on 28 ACSs, obtained aural biopsies from each dog and assessed the statistical associations between the presence of ceruminous gland hyperplasia and ectasia and disease history, clinical or microbiological findings and underlying cause of otitis externa (OE). Histological lesions of ceruminous gland hyperplasia and ectasia were observed in aural biopsies from 6/13 clinically healthy ears and 13/15 ears with OE from 19/28 examined dogs. Nine of 28 dogs had histologically normal ceruminous glands (odds ratio [OR] 6.2, 95% confidence interval [CI] 1.1-36.6). Bacterial growth in microbiological culture of aural exudate (OR 14.1, 95% CI 2.1-95.3) was associated with ceruminous glandular changes, whereas previous history of OE, cutaneous findings or underlying allergies were not. Pedigree analysis and a genome-wide association study (GWAS) were performed on 18 affected and eight unaffected dogs based on histopathological diagnosis. While the GWAS indicated a tentative, but not statistically significant, association of ceruminous gland hyperplasia and ectasia with chromosome 31, a larger cohort is needed to confirm this preliminary result. Based on our results, ceruminous gland hyperplasia and ectasia may also precede clinical signs of OE in ACSs and a genetic aetiological component is likely Further studies with larger cohorts are warranted to verify our preliminary results.

Berries as a potential transmission vehicle for taeniid eggs.

Potential role of wild forest berries as a transmission vehicle for taeniid eggs was examined using non-zoonotic Taenia laticollis eggs as a model. The berries studied were bilberries (Vaccinium myrtillus) (1 m2 plot, n = 10) and lingonberries (Vaccinium vitis-idaea) (1 m2 plot, n = 11). The plots in the managed forest were evenly sprayed with 30,000 or 60,000 T. laticollis eggs suspended in water, and berries were collected 24 h after spraying. The berries were rinsed with water, and the water was sieved through a 1-mm and a 63-µm sieve to remove coarse material and through a 20-µm sieve to collect possible eggs. A small proportion of the sieved material was examined by microscopy after treatment with fluorescent Calcofluor White stain, which binds to eggshell chitin. In the recovery tests in artificially spiked samples, the detection limit was 5 eggs in 100 g of commercial frozen bilberries and lingonberries. Taeniid eggs were detected in all of the 10 experimentally contaminated bilberry samples and in 10 of 11 lingonberry samples. The sieved debris was also analyzed for T. laticollis DNA using semi-quantitative PCR. All samples were positive in quantitative SYBR Green real-time PCR using a T. laticollis-specific primer pair amplifying a short fragment of mitochondrial NADH dehydrogenase subunit 1 gene. This indicates that forest berries contaminated in shrubs contained T. laticollis eggs, and that berries can serve as a vehicle for taeniid eggs and may pose a possible risk to humans.

A new SYBR green real-time PCR assay for semi-quantitative detection of Echinococcus multilocularis and Echinococcus canadensis DNA on bilberries (Vaccinium myrtillus).

Berries and vegetables are potential transmission vehicles for eggs of pathogenic parasites, such as Echinococcus spp. We developed a SYBR Green based semi-quantitative real-time PCR (qPCR) method for detection of Echinococcus multilocularis and Echinococcus canadensis DNA from berry samples. A set of primers based on the mitochondrial NADH dehydrogenase subunit 1 (nad1) gene was designed and evaluated. To assess the efficacy of the assay, we spiked bilberries (Vaccinium myrtillus) with a known amount of E. multilocularis eggs. The detection limit for the assay using the NAD1_88 primer set was 4.37 × 10-5 ng/µl of E. multilocularis DNA. Under artificial contamination of berries, 50 E. multilocularis eggs were reliably detected in 250 g of bilberries. Analytical sensitivity of the assay was determined to be 100% with three eggs. As an application of the assay, 21 bilberry samples from Finnish market places and 21 bilberry samples from Estonia were examined. Previously described sieving and DNA extraction methods were used, and the samples were analyzed for E. multilocularis and E. canadensis DNA using semi-quantitative real-time PCR and a melting curve analysis of the amplified products. Echinococcus DNA was not detected in any of the commercial berry samples. This easy and fast method can be used for an efficient detection of E. multilocularis and E. canadensis in bilberries or other berries, and it is applicable also for fruits and vegetables.