Clinical diagnosis and outcome of cervicofacial cellulitis in pyrexic rabbits: six cases (2014-2021)

OBJECTIVES

To assess the signalment, history, exam findings, diagnostics, treatment and outcome of rabbits diagnosed with pyrexia and concurrent cervicofacial cellulitis.

MATERIALS AND METHODS

Retrospective evaluation of medical records of rabbits diagnosed with cervicofacial cellulitis and pyrexia based on physical exam, contrast-enhanced CT, clinicopathology and microbiology findings.

RESULTS

Six out of 1588 rabbits met the study inclusion criteria. Rabbits presented with a median age of 6 years (range, 8 months to 8 years) with a presenting complaint of anorexia or hyporexia. All rabbits had a rectal temperature >40.2°C (104.4°F). Physical exam and contrast-enhanced CT revealed unilateral submandibular and ipsilateral cervical diffuse soft tissue swelling in five of six rabbits. No antemortem evidence of periodontal or dental disease was found on physical exam or CT. Leucopenia was present in five of six rabbits. A left shift with marked toxic changes was present in all four rabbits, for which blood smears were reviewed. Bacterial cultures of the aspirated subcutaneous soft tissue swelling cultured Escherichia coli, Pasteurella multocida, Granulicatella adiacens, Streptococcus species, Haemophilus species and Bacteroides species. Treatment was pursued in five rabbits, where all rabbits received supportive care and four of five rabbits received systemic antibiotics. One rabbit was euthanased following a diagnosis of cervicofacial cellulitis. Three out of five rabbits continued to decline clinically despite medical management, and thus, euthanasia was pursued within 24 hours of starting treatment. Two rabbits responded to initial treatment and developed subsequent multi-focal abscessation. One rabbit was euthanased due to client cost constraints, and one rabbit died shortly after achieving clinical resolution of cervicofacial cellulitis.

CLINICAL SIGNIFICANCE

Cervicofacial cellulitis should be considered a differential diagnosis in pyrexic rabbits with facial or cervical swelling with medical and surgical management pursued for therapy.

Effects of commercial metronidazole and metronidazole benzoate suspensions on food intake in chinchillas

OBJECTIVES

To evaluate if commercially available metronidazole and metronidazole benzoate suspensions cause a reduction in food intake in healthy chinchillas and if the reduction in food intake is dose-dependent.

MATERIALS AND METHODS

Twelve chinchillas were used in a randomised, controlled, blinded, complete-crossover study. All treatments were administered orally every 12 hours for 3 days. Metronidazole (125 mg/mL) was administered at 20 mg/kg and metronidazole benzoate (25 mg/mL) was administered at 20 and 10 mg/kg. Food intake was recorded daily. The washout period between treatments was at least 14 days.

RESULTS

At 20 mg/kg PO q12h administration of both commercial suspensions resulted in a significant reduction of food intake. The greatest mean reduction in food intake occurred after 2 to 3 days of drug administration (metronidazole: -54 ± 25%; metronidazole benzoate: -44 ± 36%). After administration of metronidazole benzoate at 10 mg/kg PO q12h, the reduction in food intake was significantly less pronounced (-24 ± 36%), suggesting that negative effect of metronidazole on food intake in chinchillas is dose-dependent. Variation in metronidazole-induced food intake reduction differed widely between individual chinchillas.

CLINICAL SIGNIFICANCE

The oral administration of commercial metronidazole and metronidazole benzoate suspensions results in a dose-dependent clinically relevant reduction in food intake in chinchillas. Metronidazole should be used cautiously in this species and food intake should be monitored during treatment. Future studies are needed in order to determine if metronidazole at 10 mg/kg q12h is an effective therapeutic dosage in chinchillas.

Angiofibroma in a cockatiel (Nymphicus hollandicus)

Human angiofibromas are rare and arise typically in the nasopharynx. In veterinary medicine they have only been described in the dog. Microscopically, angiofibromas consist of irregular groups of blood vessels within a stroma of connective tissue, with oedema and secondary inflammation often present. A cockatiel (Nymphicus hollandicus) was presented with an oral mass that consisted of aggregates of blood vessels surrounded by a connective tissue stroma, with the presence of oedema and secondary inflammation. Tumours of the oral cavity are uncommon in birds and to the authors' knowledge this is the first case of avian angiofibroma.

Subspectacular nematodiasis caused by a novel Serpentirhabdias species in ball pythons (Python regius)

Subspectacular nematodiasis was diagnosed in three captive-bred juvenile ball pythons (Python regius) from two unrelated facilities within a 6-month period. The snakes were presented with similar lesions, including swelling of facial, periocular and oral tissues. Bilaterally, the subspectacular spaces were distended and filled with an opaque fluid, which contained nematodes and eggs. Histopathology showed nematodes throughout the periocular tissue, subspectacular space and subcutaneous tissue of the head. The nematodes from both facilities were morphologically indistinguishable and most closely resembled Serpentirhabdias species. Morphological characterization and genetic sequencing indicate this is a previously undescribed rhabdiasid nematode.

Diagnosis and management of oviductal disease in three red-eared slider turtles (Trachemys scripta elegans)

Three mature, female, red-eared slider turtles (Trachemys scripta elegans) were individually, and separately, diagnosed with different forms of oviductal disease. Case 1 presented with acute cloacal bleeding and was diagnosed with acute oviductal rupture and ectopic eggs in the coelom. Case 2 presented for repeated scratching in the direction of the cloaca and was diagnosed with chronic oviductal impaction and coelomitis. Both cases were treated successfully by endoscopy-assisted complete ovariosalpingectomy via a bilateral prefemoral approach. Case 3 presented with a reduced appetite and signs of nesting behaviour and was diagnosed with obstructive dystocia associated with bacterial salpingitis. Successful treatment consisted of transcloacal egg removal and systemic antibiotics. Complete recovery was achieved in all three turtles, which remained disease-free 23 to 33 months later. Oviductal disease can present with a variety of clinical signs, and an accurate diagnosis can be made based on a thorough history, physical examination and appropriate diagnostic techniques.

History dependence of circadian pacemaker period in the cockroach

The freerunning period of circadian clocks in constant environmental conditions can be history-dependent, and one effect of entrainment of circadian clocks by light cycles is to cause long-lasting changes in the freerunning period that are termed after-effects. We have studied after-effects of entrainment to 22-h (LD 8:14) and 26-h (LD 8:18) light cycles in the cockroach Leucophaea maderae. We find that in cockroaches, the freerunning period of the locomotor activity rhythm, measured in constant darkness (DD), is 0.7h less after entrainment to T22 than after entrainment to T26. Induction of after-effects requires several days (>1 week) entrainment, and after induction, after-effects will persist in DD for over 40 days. Further after-effects are unaltered by phase-resetting of up to 12h caused by exposure to low-temperature pulses (7 degrees C) of 24 or 48h duration. After-effects also persist through re-entrainment for 2 weeks to 24-h light cycles. These results indicate that after-effects arise from stable changes in the circadian system that are likely to be independent of phase relationships among oscillators within the circadian system. We also show that entrainment to temperature cycles does not generate after-effects indicating that light may be unique in its ability to generate lasting changes in pacemaker period.