Detection of gastrointestinal parasitism at recreational canine sites in the USA: the DOGPARCS study

Abstract

Background: The rapid growth in off-leash dog parks provides opportunity for canine socialization activities but carries risk of exposure to intestinal parasites. This study assessed the prevalence of these infections in dogs visiting off-leash dog parks.Methods: Fresh defecations were collected from dogs visiting parks in 30 metropolitan areas across the USA. Samples were analyzed by coproantigen immunoassay (CAI) (Fecal Dx® and Giardia Test, IDEXX Laboratories, Inc.) and zinc sulfate centrifugal flotation (CF). Owners responded to a questionnaire on their dog’s signalment and use of heartworm/intestinal parasite control medications (HWCM).Results: Samples were examined from 3006 dogs, 87.9% aged at least 12 months, visiting 288 parks. At least one intestinal parasite was detected in 622 (20.7%) samples, nematodes in 263 (8.8%), with hookworms, whipworms and ascarids in 7.1, 1.9 and 0.6% of samples, respectively. A sample positive for one or more intestinal parasites was found in 245 (85.1%) parks, with nematodes found in 143 (49.7%). Combined, CAI and CF detected 78.4% more intestinal nematode infections than CF alone. Hookworm and whipworm infections were detected in all age groups, but ascarids were only detected in dogs less than 4 years-old. Approximately 42% of dogs aged less than 1 year were positive for nematodes or Giardia. Based on owner reports, HWCM was current for 68.8% of dogs, dogs previously diagnosed with intestinal parasitism were more likely to be receiving a HWCM than those without such history, and a significantly lower (P = 0.0003) proportion of dogs receiving a HWCM were positive for intestinal nematodes compared with those not on such medication.Conclusions: Intestinal parasites, the most common of which were Giardia, Ancylostoma caninum and Trichuris vulpis, were found in 20% of dogs and 85% of dog parks across the USA. Enhanced detection of canine intestinal parasitism was achieved by combining CF and CAI. Canine intestinal parasites are common across the USA and dog health can be improved by regular testing of fecal samples and routine administration of medications effective against the most common infections.

Canine nematode and Giardia spp. infections in dogs in Edmonton, Alberta, the “CANIDA” study

“…in 5.8% of samples. This is comparable (4%) with a large national survey in the US (Little et al) but lower than that reported in other studies using similar techniques reported by Stafford et al and Sweet et al [2,3,8]. Reliance on flotation alone, Giardia spp.…”

“…Nematodes (hookworms, whipworms, and ascarids) collectively were present in 2.3% of dogs. Stafford et al reported values from 2.8% (west) to 17.1% (southeast) depending on the region of the USA where the samples were collected [8]. In a national study conducted in Canada, Villeneuve et al found higher prevalence of ascarids (8.2%) in Alberta and hookworm (5.6% nationally); however, dogs were surveyed from shelters, and the prevalence is likely higher than in client-owned dogs [9].…”

Corpus callosum abnormality in a puppy with hypernatraemia

“…Dogs less than 1 year of age are at increased risk of nematode and Giardia spp. infections, and as the dog had no reported deworming since being adopted from the breeder, it is possible that the dog had intestinal parasitism leading to diarrhoea 7 . In the presence of increased losses through diarrhoea, a dog with hypodipsia may not be able to maintain hydration, resulting in hypernatraemia.…”

Field study to investigate the effectiveness and safety of a novel orally administered combination drug product containing milbemycin oxime and lotilaner (Credelio® Plus) against natural intestinal nematode infections in dogs presented as veterinary patients in Europe

“…In this study, a number of both IP-and CP-treated dogs had Day 0 pre-treatment FEC numbers that were very high for the species identified (e.g. T. canis range of 1-1275 and 1-574 for IP and CP, respectively), in line with overdispersion of parasites in dog populations, but at the same time confirming the potentially high risk of environmental contamination by non-treated, infected dogs in home environments and those locations shared with other dogs [34,35]. The zoonotic potential of T. canis and pathogenic disease caused by A. caninum are well documented, including Europe [5-8, 32, 33].…”