Emphysematous pyometra and emphysematous hepatitis caused by Klebsiella pneumoniae infection in a diabetic dog.

A 14-year-old intact female diabetic dog presented with seizures and hyperglycemic hyperosmolar syndrome. Radiographs revealed gas-filled tubular structures in the right and left caudal abdomen, raising concerns of emphysematous pyometra or small intestinal ileus. Ultrasonography played a pivotal role in confirming emphysematous pyometra, a technique previously documented only once in veterinary practice. This report also presents the first documented case of emphysematous pyometra in a diabetic dog attributed to Klebsiella pneumoniae and complicated by emphysematous hepatitis.

Erysipelas with preferential brain and skin involvement in a Mediterranean bottlenose dolphin Tursiops truncatus.

Infections by Erysipelothrix rhusiopathiae occur in domestic animals and cause the disease known as 'erysipelas'. The ubiquity of Erysipelothrix spp. makes infection possible in a wide range of vertebrates and invertebrates. Cetaceans are highly susceptible to erysipelas, especially those under human care. The number of cases documented in wild cetaceans is low, the pathogenesis is incompletely understood, and the full spectrum of lesions is not well defined. The possible serotypes and species of the genus that can cause disease are unknown. In October 2022, a common bottlenose dolphin Tursiops truncatus stranded in Vilassar de Mar (Catalonia) showing skin lesions consistent with 'diamond skin disease', a characteristic lesion of erysipelas shared by swine and cetaceans. Necropsy was performed following standardized procedures, and multiple samples were taken for histopathology and bacteriology. Erysipelothrix sp. grew in pure culture in many tissue samples. Genetic characterization by multi-locus sequence analysis identified the species as E. rhusiopathiae. Histologically, the main lesions were an intense suppurative vasculitis of leptomeningeal arteries and veins with abundant intramural Gram-positive bacilli and meningeal hemorrhages. Meningeal lesions were considered the cause of death. The affected skin showed moderate suppurative dermatitis. Herein we document a case of erysipelas in a Mediterranean common bottlenose dolphin with unusual lesions in the leptomeningeal vessels and marked skin tropism. To our knowledge, this is the first case of severe brain involvement in erysipelas in a cetacean. We also provide a review of available cases in wild cetaceans, to highlight the characteristics of the disease and improve future diagnosis.

Tension pneumothorax in small odontocetes.

Pneumothorax, the accumulation of air in the pleural cavity, occurs when air enters the pleural space by the pleuro-cutaneous, pleuro-pulmonary, or pleuro-oesophageal-mediastinal route. Tension pneumothorax is an infrequent and severe form of pneumothorax where a positive pressure in the pleural space is built up during at least part of the respiratory cycle, with compression of both lungs and mediastinal vessels, and, if unilateral, with midline deviation towards the unaffected hemithorax. We describe 9 cases of tension pneumothorax in 3 species of small cetaceans (striped dolphin Stenella coeruleoalba, common dolphin Delphinus delphis, and common bottlenose dolphin Tursiops truncatus) from the western Mediterranean coast of Spain, and one case from a dolphinarium. Computed tomography (CT) imaging performed in 2 carcasses before necropsy showed lung compression, midline deviation, and pressure on the diaphragm, which was caudally displaced. Tension pneumothorax was recognized at necropsy by the presence of pressurized air in one of the hemithoraces. Seven of the pneumothorax cases were spontaneous (2 primary and 5 secondary to previous lung pathology). In the other 2 dolphins, the pneumothorax was traumatic, due to oesophageal-pleural perforation or rib fractures. We hypothesize that pneumothorax in dolphins is predominantly tensional because of their specific anatomical and physiological adaptations to marine life and the obligate exposure to extreme pressure changes as diving mammals.

Causes of cetacean stranding and death on the Catalonian coast (western Mediterranean Sea), 2012-2019.

The causes of cetacean stranding and death along the Catalan coast between 2012 and 2019 were systematically investigated. Necropsies and detailed pathological investigations were performed on 89 well-preserved stranded cetaceans, including 72 striped dolphins Stenella coeruleoalba, 9 Risso's dolphins Grampus griseus, 5 bottlenose dolphins Tursiops truncatus, 1 common dolphin Delphinus delphis, 1 Cuvier's beaked whale Ziphius cavirostris and 1 fin whale Balaenoptera physalus. The cause of death was determined for 89.9% of the stranded cetaceans. Fisheries interaction was the most frequent cause of death in striped dolphins (27.8%) and bottlenose dolphins (60%). Cetacean morbillivirus (CeMV) was detected on the Catalan coast from 2016 to 2017, causing systemic disease and death in 8 of the 72 (11.1%) striped dolphins. Chronic CeMV infection of the central nervous system was observed from 2018-2019 in a further 5 striped dolphins. Thus, acute and chronic CeMV disease caused mortality in 18% of striped dolphins and 14.6% of all 89 cetaceans. Brucella ceti was isolated in 6 striped dolphins and 1 bottlenose dolphin with typical brucellosis lesions and in 1 striped dolphin with systemic CeMV. Sinusitis due to severe infestation by the nematode parasite Crassicauda grampicola caused the death of 4 out of 6 adult Risso's dolphins. Maternal separation, in some cases complicated with septicemia, was a frequent cause of death in 13 of 14 calves. Other less common causes of death were encephalomalacia of unknown origin, septicemia, peritonitis due to gastric perforation by parasites and hepatitis caused by Sarcocystis spp.

Characterization of housing-related spontaneous variations of gut microbiota and expression of toll-like receptors 2 and 4 in rats.

Gut microbiota has been suggested as a key component of gut homeostasis, affecting immune responses within the gut. We determined changes in intestinal commensal bacteria and expression of toll-like receptors (TLR) 2 and 4 in rats bred under microbiologically controlled conditions (barrier), under standard conditions (conventional), and in barrier animals adapted to standard conditions (barrier/conventional). Cecal microbiota was analyzed by plate culture, and fluorescence in situ hybridization and microbial profiles were assessed by terminal restriction fragment length polymorphism. Cecal expression of TLR-2 and TLR-4 was determined by reverse transcription polymerase chain reaction (PCR). Total number of cecal bacteria was similar in the three groups. However, the barrier group showed a higher number of strict anaerobic bacteria (Bacteroides spp. and Clostridium spp.) while Bifidobacterium spp. were scarce. Re-housing the barrier-bred rats into conventional conditions led to a microbiota with intermediate characteristics between the barrier and conventional groups. Richness of the cecal microbial ecosystem was similar in the three groups, although a relative time-dependent variation, with highest homogeneity in the barrier group, was observed. Expression levels of TLR-2 and TLR-4 had no clear correlation with the microbiota. These results show that the relative composition of the cecal microbiota in rats varies spontaneously with changes in the environmental conditions, with minor impact in the expression of TLR-2 and TLR-4. These observations might be important in the understanding of variability in animal responses, particularly to immune-related stimuli, when assessed in the context of the environmental/microbiological conditions.

Foot infections associated with Arcanobacterium pyogenes in free-living fallow deer (Dama dama).

We describe foot infection associated with Arcanobacterium pyogenes in three adult male free-living fallow deer (Dama dama) from Sueve Regional Hunting Reserve (Principality of Asturias, Spain). Affected fallow deer were culled in November 1997 and 1998 during the hunting season. Necropsy, radiography, and microbiologic analysis were carried out for each animal. Unilateral swelling of one extremity at the coronary band was observed in all three cases. Areas of bone loss, severe periosteal reaction, and soft tissue swelling were seen on radiography. Lead fragments were observed in one fallow deer. Seven bacterial species were isolated, but only Arcanobacterium pyogenes was routinely found. Weather conditions in the area (mild temperatures and high humidity), the land (alternating pasture land and rock), the animal population density (both fallow deer and domestic herds of cows, horses, sheep, and goats, live side by side in the same areas), and hunting activities could be related to the frequency of these infections.