Hello, Vetaheader! We are back with a brand new newsletter. This time, it is a bit different! We are bringing some highlights of the 2023 ExoticsCon proceedings, with topics that will likely interest you. I’ve separated them in topics, so it will be easier to read. Without further ado, let’s  go!

• Birds

  • You may have heard that using corticosteroids can have deleterious effects in birds. Well, an abstract reported the prolonged use of prednisone in pigeons (Columba livia). Six birds were used in the treatment group (prednisolone 1 mg/kg PO q24h for 29 days) while five were used as control (NaCl 0.9%). Their results showed no adverse clinical, clinicopathologic, or histopathologic changes in the treated birds compared to the control birds! (Petritz et al., page 41)

  • The effects of different drugs on birds’ food intake was assessed:

    • The effects of capromelin on pigeons (Columba livia) was tested. A 12 mg/kg PO q24h dose was shown to be effective in inducing greater daily food intake and weight gain over 6 days. (Trumpp et al., pages 237-238)

    • The effects of capromelin, mirtazapine and cyproheptadine were tested in budgerigars (Melopsittacus undulatus). The findings are as follows (Mans et al., page 42):

      • Mirtazapine (1 and 5 mg/kg PO) – no clinically relevant or statistically significant effects on food intake were found, regardless of the dose administered.

      • Capromorelin (10 and 40 mg/kg PO) – food intake was significantly increased for the first 8 hours compared to the control treatment; however, regurgitation was observed in 42% and 92% of birds following administration of capromorelin at 10 and 40 mg/kg, respectively. The findings suggest that capromorelin at 10 mg/kg should be considered for future studies, but lower doses may be effective in increasing food intake with less adverse effects.

      • Cyproheptadine (0.5 and 2.5 mg/kg PO) – no clinically relevant or statistically significant effects on food intake were found, regardless of the dose administered.

    • The effects of benzodiazepines was assessed in budgerigars (Melopsittacus undulatus). The animals received either midazolam (1 mg/kg and 0.5 mg/kg IM once) or diazepam (1 mg/kg IM once) in a randomized, controlled, blinded, complete crossover study. The results showed that both midazolam and diazepam at 1 mg/kg resulted in a significant increase in food intake compared to the control treatment. The results suggest that either drug can be used clinically as a short-acting appetite stimulant in budgerigars. (Mans et al., page 240)

  • Beak trimming may seem like a quick and easy procedure, but beaks are live structures, and require attention! An abstract reported the use of novel stain (Scarlet Tissue Stain), micro CT, and histology to visualize and characterize bone papillae in the upper and lower beaks of African grey parrots (Psittacus erithacus). Their results further emphasize the need for lateral radiographs of the bird’s head and beak prior to considering performing beak trims to identify the location of the underlying bone relative to the overlying rhampotheca. Also, the authors recommend the rostral tomia should not be trimmed closer than 8-10 mm from the underlying bone! (Lessner et al., pages 224-227)

• Mammals

  • The effects of different drugs on chinchillas’ food intake was assessed:

    • The use of capromorelin and mirtazapine was tested for their appetite-stimulating effects (Mans, page 296): 

      • Capromorelin was evaluated at 3 and 10 mg/kg PO q24h in normorexic chinchillas and at 10 mg/kg PO q24h in chinchillas with experimentally induced post-sedation hyporexia.  Capromorelin significantly increased food intake in normorexic animals and attenuated the sedation-induced reduction in food intake.

      • Mirtazapine was evaluated at 5 and 20 mg/kg PO q24h in normorexic chinchillas and at 20 mg/kg PO q24h in a study in chinchillas with experimentally induced post-sedation hyporexia. Mirtazapine did not have any significant or clinically relevant impact on food intake compared to the control.

    •  The use of metronidazol and tinidazole was tested in a randomized, controlled, complete-crossover study (Mans, page 306): 

      • Metronidazole (10 or 20 mg/kg q12h for 3 days) was administered, and the 20 mg/kg PO q12h dosage induced a reduction in food intake within 24 hours after starting the treatment. At 10 mg/kg PO
        q12h, the reduction in food intake was around half of that of the 20 mg/kg, suggesting that the negative effect of metronidazole on food intake in chinchillas is dose-dependent. 

      • Tinidazole (100 mg/kg or 200 mg/kg PO single dose, and 20 mg/kg PO q12h for 5 days) was administered. The repeated administration of tinidazole at 20 mg/kg q12h did not result in any clinically relevant or statistically significant reduction in food intake compared to the control treatment, suggesting it can be considered as a safe alternative to metronidazole in chinchillas.

  • A retrospective study was conducted to help determine parameters which may guide the decision to perform orogastric decompression in rabbits diagnosed with GI obstruction. Their findings suggest that radiographic findings, when correlated with the severity of hyperglycemia (avg. 25.7 mmol/L; 463 mg/dl) and hyponatremia (Na < 138 mmol/L; 138 mEq/L) could support the need for performing orogastric decompression. The cases reviewed showed that patients that were treated successfully with either medical management or orogastric decompression and medical management did not require surgical intervention. (Steinagel & Oglesbee, pages 439-440) – these findings have been published as a peer-reviewed paper, and you can read it here. For those who are Essential members, check the 3rd edition of the e-book for our rabbit course’s lesson 5! We give you the highlights there.

  • The efficacy of a single-use supraglottic airway device (SGAD) designed for small rabbits (V-Gel ADVANCED R1) was tested in hedgehogs. The hedgehogs were maintained for 30 minutes) using either a rabbit SGAD or a rodent nosecone in a randomized, complete cross-over study. Once the SGAD was placed, animals were randomly rotated into four different recumbencies to assess for dislodging of the device. The median time to successful SGAD placement was 15 seconds, and the device allowed for positive-pressure ventilation. No significant difference between treatments was found in retrospective rigid oropharyngoscopy evaluation, as well as in daily food intake and running wheel. The findings suggest that the use of the SGAD in hedgehogs appears effective and safe for anesthetic maintenance. (Doss et al., page 448)

  • A clinically useful pain assessment scale for guinea pigs is current in the making! It is based on pre-existing pain scales for other species and indicators of pain in guinea pigs described in the literature. The researchers assessed 14 descriptors, grouped in four categories (appearance, functional, physiological, and behavioral). The experimental study for the validation of this scale was conducted on 45 adult guinea pigs, and statistical analysis showed that the scale had very good repeatability and intra-operator reproducibility. However, some items needed to be clarified for the proper understanding of the scale, so further ongoing studies include modifications of these items and the use of a larger number of animals to improve this scale for clinical use. (Pignon et al., page 449)

• Reptiles

  • A retrospective study was conducted to describe clinical and pathological cardiovascular disease in bearded dragons (Pogona vitticeps), with a total of 54 cases over a 15-year period. The results showed an overall prevalence of 3.3%, with median age of 5 years (range 0.6-11). The majority of cases (81.5%) were diagnosed on necropsy alone (n = 44). In total, 81 diagnoses of cardiovascular disease were found , with the most common diagnoses being myocarditis (n = 14), aneurysms (n = 11), atherosclerosis (n = 7), epicarditis (n = 7), myocardial degeneration/necrosis (n = 7), pericardial effusion (n = 7), neoplasia (n = 6), and vasculitis (n = 5). The small number of cases diagnosed antemortem show the need for further research on the diagnosis and therapeutic options for cardiovascular disease in this species. (Ozawa et al., pages 525-526)

  • A retrospective study was conducted to evaluate the incidence and prognosis of cloacal prolapses in reptiles (lizards, chelonians, and snakes), with a total of 2228 cases, spanning over 8 years. The results showed that 4% of patients presented with cloacal prolapses, with 90.9% of cases occurring in patients older than 1 year of age. Lizards presented more frequently (56%) than chelonians (34%) and snakes (9.8%). In lizards, true cloacal prolapses presented more commonly, while penile/hemipenile prolapses were the most identified prolapse in chelonians and snakes. (Fogli & Dutton, page 530)

  • The need for UVB supplementation for nocturnal species such as the leopard gecko (Eublepharis macularius) has long been debated, and recent publications have shown that UVB exposure does increase plasma 25-hydroxyvitamn D3 (25-OHD3) concentrations in this species. However, excessive UVB exposure can lead to squamous cell carcinoma and cataracts, so a study was conducted to determine the minimal amount of UVB exposure required to increase 25-OHD3 concentrations in this species. The results showed that mean baseline 25-OHD3 was 29 nmol/L, and there was a significant difference over time, with higher concentrations at 28 days compared to baseline, regardless of length of exposure tested (15, 30 or 60 minutes daily). (Bitter et al., page 552)

  • An experiment with corn snakes (Pantherophis guttatus) aimed to find the sensitivity of plasma biochemical and blood gas parameters to detect renal disease. Contrary to what has been proposed in tortoises, SDMA (symmetric dimethylarginine) was not an indicator of renal lesions. Ionized calcium, total calcium, and lactate concentrations were the earliest indicators of renal lesions for this species. (Vergneau-Grosset et al., page 694)

  • The use of veterinary and human portable blood glucometers in bearded dragons (Pogona vitticeps) was evaluated. AlphaTrak II (canine and feline settings), AccuChek Guide and LDX were the models used, and the results showed that AlphaTrak overestimated blood glucose (BG), while AccuChek and LDX underestimated BG. However, when corrective formulas were applied, all analyzers were within clinical decision limits; so, as long as species-specific corrective formulas or method-specific reference intervals are utilized, these methods are valid for evaluating BG. (Tabert et al., pages 713-714)

Phew! This was a long one. Hope you find it useful and, as always, I will see you next month.

Sincerely,