There are several types of commercial rodenticides, with anticoagulant, bromethalin, and cholecalciferol being the most commonly used. Each type of rodenticide has a different affect on the bird, and requires treatment unique to the type of rodenticide ingested. Because there are so many differences, if rodenticide toxicity is suspected, the trade name of the product, generic active ingredient, and concentration of the active ingredient are important to obtain. The EPA registration number can also be used to accurately identify a rodenticide. In most cases, the color and formulation (blocks versus place packs) do not provide accurate clues to the type of rodenticide.
Anticoagulants - Anticoagulants cause a severe loss of vitamin K levels in the bird's body. The severity depends on the amount of the rat poison ingested by the bird, and the toxicity of the individual product. Signs of poisoning don't happen right away. It will take generally 3 to 7 days for clinical signs to appear in ducks, post ingestion of the poison. Initial signs are related to internal bleeding so they are often vague, and may include weakness, lethargy, and decrease or loss in appetite. The chicken may also be found dead, without clinical signs developing.
Bromethalin - Bromethalin baits will be formulated as place packs and bars, like anticoagulants. Product brands include several including Trounce, Assault, and Vengeance. Clinical signs of toxicity are related to the nervous system and include muscle tremors, seizures, behavioral changes, ataxia, paresis, and depression. If recognized early enough (within 4 hours of suspected ingestion of the poison), giving activated charcoal may be beneficial. After 4 hours and once clinical signs have developed, treatment consists of therapy for the associated symptoms which develop and supportive. In mild cases, signs may resolve on their own over 2-4 days with good nursing and supportive care.
Cholecalciferol - Cholecalciferol is actually vitamin D3. Commercial brands include Quintox, Rampage, and Hyperkil. Poisoning severity depends on the dose and age and sex of the bird. It severe causes hypercalcemia. If recognized early enough (within 4 hours of ingestion), activated charcoal may be beneficial. After four hours, aggressive treatment for hypercalcemia is needed and supportive care.
Case 1: Anticoagulant Rodenticide Poisoning in a Condor A 28-year-old female Andean condor housed in an outside exhibit at the National Aviary in Pittsburgh, PA, began showing signs of weakness. Toxicosis with an anticoagulant rodenticide was suspected because its mate had died 1 day earlier from possible brodifacoum poisoning. A rapid decline in the packed cell volume, despite vitamin K1 treatment, necessitated a blood transfusion with blood from bald eagles and Steller's sea eagles. Supportive therapy after transfusion included vitamin K1 (5 mg/kg IM q12h) as well as enrofloxacin, vitamin B complex, selenium and vitamin E, and subcutaneous fluids as needed. After a 39-day treatment period, a tapering dosage of vitamin K1 was initiated, and treatment ended after 17 weeks. However, 2 weeks later, the bird suffered from a potential relapse. It was successfully treated with a repeat tapering vitamin K1 regimen lasting a total of 4 months. Ref
Case 2: Anticoagulant rodenticide toxicosis in a Backyard chickens Anticoagulant rodenticide toxicosis was diagnosed in a backyard chicken with dark red/black stained contents in the gizzard and pale organs (perhaps due to internal bleeding). The bird also had severe carcinomatosis. Ref