Brodifacoum Toxicosis in Two Neonatal Puppies

Abstract

Abstract. Eight out of a litter of 13 puppies were either born dead or died within 48 hours of birth. Three puppies that died shortly after birth were necropsied. Two puppies had hemorrhage in the thoracic and peritoneal cavities, intestinal serosa, and meninges. The third puppy was smaller than the other two puppies but did not have detectable hemorrhage. Brodifacoum, a second-generation coumarin anticoagulant, was detected in livers from the two puppies with hemorrhage. The dam did not have clinical signs of coagulopathy before or subsequent to whelping. The owners were confident that the dog had not been exposed to rodenticide for at least 4 weeks before whelping. A presumptive diagnosis of in utero brodifacoum toxicity was made. To the authors' knowledge this is the first time a second-generation coumarin anticoagulant has been detected in the liver of a newborn animal. This case is also unique because the dam was unaffected, suggesting that fetuses are more susceptible to brodifacoum toxicity than adult animals.Key words: Anticoagulant; brodifacoum; canine; coagulopathy; coumarin; transplacental; vitamin K.A 1-year-old Great Pyrenees bitch that was housed at a breeding kennel gave birth to 13 puppies after 63 days of gestation. Whelping was observed and was considered normal. However, two puppies were born dead, three died within 6 hours, and three died between 6 and 48 hours of birth. Four of the six puppies that died postpartum had variable hemoptysis or epistaxis before death. Two puppies were reported to have died suddenly without previous clinical signs of disease. The birth weight of the eight puppies that were born dead or died was 280 Ϯ 107 g (mean Ϯ 1 SD), whereas the birth weight of the five puppies that survived was 502 Ϯ 57 g (mean Ϯ 1 SD).The three puppies that were born alive but died within 6 hours of birth were necropsied. The abdominal cavities of two puppies (puppy Nos. 1 and 2) each contained approximately 40 ml of uncoagulated blood. Both puppies also had approximately 15 ml of uncoagulated blood within the thoracic cavity. However, one (puppy No. 3) did not have visible hemorrhage. Representative tissue samples from all three puppies were fixed in 10% buffered formalin and routinely processed for histologic examination. Histologic examination of tissues from puppy Nos. 1 and 2 revealed microscopic hemorrhage within the intestinal serosa and meninges. No significant lesions were observed by histologic examination of tissues from puppy No. 3. No histologic evidence of any infectious process was present in tissues from any of the puppies. Aerobic cultures of lung, liver, small intestine, and kidney from all three puppies did not yield pathogenic bacteria. Direct fluorescent antibody (American Bioresearch, Seivierville, TN) examination of kidney, lung, and liver did not reveal canine herpes virus antigen in any of the puppies.Liver samples from all three puppies were analyzed by high performance liquid chromatography (HPLC) for warfarin, bromadiolone, and brodifacoum. 17 Briefly, liver samp...

Superwarfarins

“…Internal bleeding also causes generalized pain; fever; II. AGENTS THAT CAN BE USED AS WEAPONS OF MASS DESTRUCTION lameness from bleeding into a joint; bleeding into the thorax or abdomen, brain, or pericardium; or sudden death (Braithwaite, 1982;Berny et al, 1995;Munday and Thompson, 2003).…”

“…The most common type of exposure is direct poisoning by eating a cereal-based bait containing the rodenticide. The most commonly affected household pets are dogs, followed by cats, hamsters, rabbits, and pet birds Park and Leck, 1982;Boermans et al, 1991;Woody et al, 1992;Hornfeldt and Phearman, 1996;Peterson and Streeter 1996;McConnico et al, 1997;Robben et al, 1997Robben et al, , 1998Munday and Thompson, 2003;Radi and Thompson, 2004) (Table 18.4).…”

Infectious Disease and Contaminants in Urban Wildlife: Unseen and Often Overlooked Threats

“…Contaminants that impact reproduction are found among nearly all types of chemicals used in urban areas, including anticoagulant rodenticides, insecticides, heavy metals, and industrial effluents. Primary effects of contaminants may include reduced female fertility and increased chance of miscarriage, reduction in sperm counts, altered gonad development, and hormonal or endocrine disruption (Vos et al 2000;Munday and Thompson 2003;Choi et al 2004;Robinson et al 2005). Laboratory experiments showed that lead exposure affected seminal vesicles and epididymes in cotton rats ( Sigmodon hispidus; McMurry et al 1995).…”

“…Hormonal disturbances in wildlife caused by endocrine disruptors include sex changes in riverine fish and marine snails, reproductive failure in birds, and abnormalities in the reproductive organs of American alligators ( Alligator mississippiensis; reviewed in Vos et al 2000). Anticoagulant rodenticides, the most commonly used rodenticides worldwide, are associated with increased chance of miscarriage, in utero toxicity, and decreased sperm counts (Munday and Thompson 2003;Robinson et al 2005). The breeding success for two bird species, blue tit ( Cyanistes caeruleus) and great tit ( Parus major), was reduced as a result of exposure to heavy metal pollution from a copper smelter (Eeva et al 2003(Eeva et al , 2009.With the varied and sometimes intensive use of contaminants in urban landscapes, reproductive impacts may be much more common than we know.…”

Bromadiolone Induced Oxidative Stress and Cytological Damage in Layer Birds

“…Non-target species are potentially at risk from direct consumption of bait and also through eating poisoned rodents (Berny et al, 1997). Recently, ten cases of rodenticide poisoning in dogs were observed in Texas Vet Medical Diagnostic Laboratory and two neonatal puppies (Munday and Thompson, 2003). Eason and Spurr (1995) reported brodifacoum rodenticide toxicity in 200, one week old chicks, in which hundred percent mortality was observed.…”