Current research in avian chemotherapy

Chemotherapy as a treatment modality is increasingly being used in avian oncology. Currently, most chemotherapeutic agents can only be used empirically, as pharmacokinetic data in birds are lacking.Recently, the pharmacokinetic profile of the platinum analogs,cisplatin, and carboplatin has been reported in Sulfur-crested cockatoos,paving the way for clinical and toxicity trials

Inherited copper toxicosis in a Bedlington terrier

Inherited copper toxicosis was diagnosed in a Bedlington Terrier using conventional diagnostic methods such as plasma biochemistry, hepatic copper assay, histology and electron microscopy and a recently developed DNA microsatellite marker test. The dog was successfully managed using D-penicillamine and a low copper diet

Experimental acute yellow-wood (Terminalia oblongata) intoxication in sheep

An aqueous suspension of air-dried, hammer-milled leaf of Terminalia oblongata (yellow-wood) was administered to sheep by gavage, as a single dose of 5 to 20 g (dry weight)/kg body weight. Doses of 15 g/kg, or more, caused depression, inappetence, abdominal pain and reduced ruminal movements within 24 to 48 h and some sheep also showed dyspnoea, opisthotonus and champing of the jaws. Haematology and blood gas and acid-base measurements were unaffected. In sheep given a dose of 12.5 g/kg, or more, plasma osmolality, aspartate aminotransferase activity and potassium and bilirubin concentrations increased while plasma total protein markedly decreased and plasma sodium concentration and alkaline phosphatase activity remained normal. Most sheep were necropsied 48 h after dosing. The liver showed zonal hepatocellular necrosis, the pattern of which varied with the dose given. No renal lesions were observed, although one sheep given a very high dose became azotaemic and hyperkalaemic. Hydrothorax, hydropericardium and ascites developed in sheep given doses of 15 or 20 g/kg

Rumen involvement in sheep tannic acid metabolism

Tannic acid (TA) metabolism was studied in sheep after po, intra-abomasal and ip administration. TA and its phenolic metabolites in ruminal fluid, abomasal fluid, plasma and urine were determined using high-performance liquid chromatography at various intervals post-dosing. After po administration, gallic acid (GA) and pyrogallol (PYR) were present in ruminal fluid and plasma, and GA, PYR and 4-O-methyl gallic acid (4OMGA) were found in urine. The concentration of GA in ruminal fluid and urine gradually decreased after dosing, while PYR concentration continued to rise. By contrast, after intra-abomasal dosing, GA and ellagic acid (EA) as well as TA were found in abomasal fluid, GA, 4OMGA, EA and TA were present in plasma, and GA, 4OMGA and PYR were in urine. The latter 3 metabolites were also detected in the urine after ip administration of TA. The plasma concentration of TA after intra-abomasal administration was significantly correlated with liver necrosis, and PYR concentration in ruminal fluid following po administration was significantly correlated to blood methemoglobin level. It was concluded that the methemoglobinemia seen in sheep given TA po is caused by high levels of the phenolic metabolite PYR, which is produced in the rumen. Liver and kidney necrosis, seen in sheep given TA directly into the abomasum, appears caused by unmetabolized TA rather than by metabolites