Treatment of vasculitis and dermatitis in a 59-yr-old Nile hippopotamus (Hippopotamus amphibius)

SERUM DISPOSITION OF A SINGLE DOSE OF ORALLY ADMINISTERED FIROCOXIB IN AFRICAN ELEPHANTS (LOXODONTA AFRICANA)

The time course of serum firocoxib concentrations was described after administration of two single oral doses (0.01 and 0.1 mg/kg) of commercially available firocoxib tablet (n = 4) and paste (n = 2) formulations to six healthy adult female African (Loxodonta africana) elephants. Firocoxib was quantitated by high-performance liquid chromatography. Firocoxib serum concentrations were below detectable levels after administration of 0.01 mg/kg of both formulations. A dose of 0.1 mg/kg (n = 4) of the tablet formulation had the following mean ± SD of pharmacokinetic parameters: area under the curve (AUC) 1,588 ± 362 h × ng/ml, maximum plasma concentration (C_max) 31 ± 6.6 ng/ml at 6.4 ± 1.8 h, and disappearance half-life (T1/2) 66 ± 59 h, Elephant compliance to oral administration of the paste formulation was challenging, with only two elephants accepting administration of the paste at 0.1 mg/kg. Pharmacokinetic parameters determined included AUC of 814 h × ng/ml, C_max of 44 ng/ml at Tmax of 7.0 h, and T1/2 of 36.4 h. Based on mean AUC, the relative bioavailability of paste compared to tablet formulations was 50%. Limitations of this study were the small number of participants and elephant compliance with the paste formulation. This study supports an oral dose of 0.1 mg/kg every 24 h. Multidose and IV trials are indicated to confirm firocoxib dosing requirements for African elephants.

SALT BATH AS A TREATMENT FOR IDIOPATHIC DERMATITIS IN CAPTIVE NILE HIPPOPOTAMUS (HIPPOPOTAMUS AMPHIBIUS)

Ulcerative skin lesions were observed in two captive adult female hippos (Hippopotamus amphibius) from a zoological collection. Lesions appeared as cracking, peeling, or vesicles of the skin affecting the lateral and ventral aspects of the neck, limbs, thorax, and abdomen, dorsum, toes, and perineal region. Some lesions drained blood, serum, or purulent material. Histologic evaluation of sloughed skin consisted of deep dermal collagen with bacterial cellulitis and vasculitis and superficial fungal colonization. No viral pathogens were isolated and no fungal or bacterial pathogen predominated. Minimal response to systemic antibiotics and topical treatment was observed. Commercial cattle food-grade salt was added to the exhibit pool at 2-3 g/L with complete healing of all skin lesions within a 4-mo treatment period. No complications were observed. Patient compliance with salt bath therapy was higher and results more effective compared to topical and oral treatments.

Using an Inbred Horse Breed in a High Density Genome-Wide Scan for Genetic Risk Factors of Insect Bite Hypersensitivity (IBH)

While susceptibility to hypersensitive reactions is a common problem amongst humans and animals alike, the population structure of certain animal species and breeds provides a more advantageous route to better understanding the biology underpinning these conditions. The current study uses Exmoor ponies, a highly inbred breed of horse known to frequently suffer from insect bite hypersensitivity, to identify genomic regions associated with a type I and type IV hypersensitive reaction. A total of 110 cases and 170 controls were genotyped on the 670K Axiom Equine Genotyping Array. Quality control resulted in 452,457 SNPs and 268 individuals being tested for association. Genome-wide association analyses were performed using the GenABEL package in R and resulted in the identification of two regions of interest on Chromosome 8. The first region contained the most significant SNP identified, which was located in an intron of the DCC netrin 1 receptor gene. The second region identified contained multiple top SNPs and encompassed the PIGN, KIAA1468, TNFRSF11A, ZCCHC2, and PHLPP1 genes. Although additional studies will be needed to validate the importance of these regions in horses and the relevance of these regions in other species, the knowledge gained from the current study has the potential to be a step forward in unraveling the complex nature of hypersensitive reactions.