Document Type : Original Article
Authors
1 Department of Clinical Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
2 Department of Basic Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
Abstract
Limited knowledge is available on acute intoxication with environmental toxicants in birds. This experimental study determines features of acute caffeine intoxication and clinical outcome of different treatments in pigeons. The experiment was performed in three phases. Toxicity tests were performed in phases one and two while phase three was dedicated to comparative evaluation of fluid therapy and activated charcoal with or without diazepam and/or propranolol on clinical outcome of birds. Calculated LD50 was 366 mg kg-1 although presence of regurgitation compromised the accuracy of LD50 application. The dose-response (death) curve was sharp with a slope of 8.41. Clinical signs included renal, neurological, gastrointestinal and respiratory symptoms that generally initiated in a few minutes and lasted for few hours. The approximate toxic dose (ATD) was 294 mg kg-1. Serum and brain concentrations after administration of ATD followed a normal distribution in a range of 14.6 - 83.3 mg mL-1 and 1.04 - 7.81 µg g-1, respectively. Fluid therapy and activated charcoal with or without propranolol did not affect the clinical outcome of intoxicated birds while adding diazepam and intensive therapy with all of these agents even worsened the situation. In conclusion, caffeine is a potential source of intoxication in pigeons with a fast onset of clinical signs and a sharp increase in death rates by increasing doses. Symptoms are similar to mammals with prominent neurological signs although the ATD and serum concentrations are relatively high. Intensive therapy with above mentioned drugs is not recommended. Most birds survive after resolution of transient clinical signs without any special treatment.
Keywords
- Day EJ, Dilworth BC. Toxicity of jimson weed seed and cocoa shell meal to broilers. Poult Sci 1984; 63(3): 466-468.
- Willson The clinical toxicology of caffeine: A review and case study. Toxicol Rep 2018; 5: 1140-1152.
- Peterson ME, Talcott PA. Small animal toxicology. 3rd Philadelphia, USA: WB Saunders 2012; 220-221.
- Tawde SN, Puschner B, Albin T, et al. Death by caffeine: presumptive malicious poisoning of a dog by incorporation in ground meat. J Med Toxicol 2012; 8(4): 436-440.
- Gartrell BD, Reid C. Death by chocolate: a fatal problem for an inquisitive wild parrot. N Z Vet J 2007; 55(3): 149-151.
- Varol K. Chocolate intoxication in a budgerigar. Erciyes Üniversitesi Veteriner Fakültesi Dergisi 2019; 16(1): 73-77.
- Lightfoot TL, Yeager JM. Pet bird toxicity and related environmental concerns. Vet Clin North Am Exot Anim Pract 2008; 11(2): 229-259.
- OECD Guidelines for the testing of chemicals, section 2, test No. 223: Avian acute oral toxicity test, 2016: 1-28.
- Adamson RH. The acute lethal dose 50 (LD50) of caffeine in albino rats. Regul Toxicol Pharmacol 2016; 80: 274-276.
- Alvi SN, Hammami MM. Validated HPLC method for determination of caffeine level in human plasma using synthetic plasma: application to bioavailability studies. J Chromatogr Sci 2011; 49(4): 292-296.
- Gupta RC. Veterinary toxicology: basic and clinical principles. 2nd Massachusetts, USA: Academic Press 2012; 1366-1367.
- Samour J. Avian medicine. 3rd Missouri, USA: Mosby Ltd. 2016; 22, 406.
- Tran NL, Barraj LM, Bi X, et al. Trends and patterns of caffeine consumption among US teenagers and young adults, NHANES 2003-2012. Food Chem Toxicol 2016; 94: 227-242.
- Camargo MCR, Toledo MCF. HPLC determination of caffeine in tea, chocolate products and carbonated beverages. J Sci Food Agric 1999; 79(13): 1861-1864.
- Srdjenovic B, Djordjevic-Milic V, Grujic N, et al. Simultaneous HPLC determination of caffeine, theo-bromine and theophylline in food, drinks and herbal products, J Chromatogr Sci, 2008; 46(2): 144-149.
- Arnaud MJ. Pharmacokinetics and metabolism of natural methylxanthines in animal and man, Handb Exp Pharmacol 2011; (200): 33-91.
- Vermeulen B, De Backer P, Remon JP. Drug administration to poultry. Adv Drug Deliv Rev 2002; 54(6): 795-803.
- Kerrigan S, Lindsey T. Fatal caffeine overdose: two case reports. Forensic Sci Int 2005; 153(1): 67-69.
)