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Sandy beach species are adapted to a harsh physical habitat, but for those living at relatively high latitudes, the cold, often freezing winter conditions, entail a challenge that has not been thoroughly examined. We therefore examined the individual response of talitroid amphipods (Americorchestia longicornis; Say 1818) to the strong seasonality affecting sandy beaches in Prince Edward Island, Atlantic Canada (46°N). We then experimentally assessed the influence of low temperatures upon amphipod burrowing behavior and stress levels (hemocyanin concentrations), hypothesizing that cold and freezing temperatures prompt drastic behavioral and physiological responses in the amphipods. Biweekly amphipod samples collected over three years (2019–2021) made evident the narrowness of their activity season and its tight correlation with temperature (Spearman's r = 0.85). While amphipods were abundant above 10 °C, they were very few under 5 °C and none near 0 °C. In the laboratory, amphipods exposed to 10 °C remained at shallow depths in the sand (70% at 0–4 cm of depth). By comparison, amphipods exposed to 5 °C were found at several depths (0–40 cm), while those exposed to 0 °C concentrated (70%) at depths of 16–40 cm. The assessment of stress levels showed that in comparison to amphipods at ambient temperatures, those exposed to freezing conditions exhibited hemocyanin levels 55 and 82% higher after 1 and 2 weeks, respectively. Combined, these results suggest that cold and freezing temperatures shorten the season of the amphipods and prompt them to burrow deeper into the sand and increase their stress levels, possibly influencing other life history traits. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Veterinary Journal / Revue Vétérinaire Canadienne is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Veterinary Journal / Revue Vétérinaire Canadienne is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The prevalence of Giardia duodenalis, Cryptosporidium spp. and other intestinal parasites was determined in dogs <1 year old from Prince Edward Island, Canada. Fecal samples were collected from the local animal shelter (n =62), private veterinary clinics (n =78) and a pet store (n =69). Intestinal parasites isolated included G. duodenalis, Cryptosporidium spp., Toxocara canis, Isospora spp. and Uncinaria stenocephala. To estimate the zoonotic risk associated with these infections, genotypes of G. duodenalis and Cryptosporidium spp. were determined using 16S rRNA and Hsp70 gene sequencing, respectively. Dogs from the pet store had the highest prevalence of intestinal parasites (78%, 95% CI: 68–88%), followed by the private veterinary clinics (49%, 95% CI: 37–60%), and the local animal shelter (34%, 95% CI: 22–46%). The majority G. duodenalis belonged to host-adapted assemblages D (47%, 95% CI: 31–64%) and C (26%, 95% CI: 13–43%), respectively. Zoonotic assemblages A and B were isolated alone or in mixed infections from 16% (95% CI: 6–31%) of G. duodenalis-positive dogs. All Cryptosporidium spp. were the host-adapted C. canis. While host-adapted, non-zoonotic G. duodenalis genotypes were more common, the presence of G. duodenalis assemblages A and B, T. canis, and U. stenocephala suggests that these dogs may present a zoonotic risk. The zoonotic risk from Cryptosporidium-infected dogs was minimal. [Copyright &y& Elsevier]

Abstract: In a cross-sectional study of 633 pigs from 21 herds on Prince Edward Island, Canada (PEI), the prevalence of infection with Cryptosporidium and Giardia, and the genotypes and species of isolates were determined in order to establish the zoonotic potential of pigs in this region. As determined by direct immunofluorescence microscopy (DFA), 18 herds (86%) and 163 animals (26%; 95% CI: 22–29%) tested positive for Cryptosporidium, while just 3 herds (14%) and 6 animals (1%; 95% CI: 0.4–2%) tested positive for Giardia. Cryptosporidium spp. isolates were detected in 39% (95% CI: 34–44%) of weanlings (1–3 months of age) and 9% (95% CI: 6–13) of sows (>8months of age). Molecular characterization using the 18S rDNA and HSP70 gene fragments revealed the presence of Cryptosporidium sp. pig genotype II, C. suis, C. parvum, and Cryptosporidium sp. mouse genotype. Among the 113 isolates of Cryptosporidium spp. successfully genotyped, pig genotype II (61%) predominated, with C. suis (36%) being the next most prominant isolate. C. parvum (2%; two isolates) and Cryptosporidium sp. mouse genotype (0.9%; one isolate) were only occasionally isolated. The only two Cryptosporidium-positive genotyped isolates from sows included one each of C. suis and Cryptosporidium sp. pig genotype II. All but one of the six Giardia positive isolates were detected in weanling pigs. None of the Giardia-positive isolates was amenable to PCR. This study demonstrates that Cryptosporidium spp. are highly prevalent in pigs on PEI, Canada, are found mostly in weanlings (1–3 months of age). Furthermore, the pigs are primarily infected by the host-specific genotypes and species, Cryptosporidium sp. pig genotype II and C. suis, whereas the zoonotic C. parvum is rare. Giardia duodenalis is only occasionally found in pigs. These findings suggest that domestic pigs on PEI, Canada, likely do not pose a significant health risk to humans from these parasites. [Copyright &y& Elsevier]

Abstract: The objectives of this study were to determine the prevalence and assemblages of Giardia and species of Cryptosporidium on beef farms in Prince Edward Island (PEI), Canada, including the water sources associated with the farms, and to determine risk factors for infection of cattle with these parasites. Twenty beef farms were selected based on the presence of surface water<500m from the barn. Prevalence was determined by direct immunofluorescence microscopy, while genotyping and species determination were performed by nested-PCR and DNA sequencing. Giardia was detected in 42% (95% CI: 38–46%) of fecal samples from 100% farms while Cryptosporidium was detected in 17% (95% CI: 14–19%) of fecal samples from 80% of farms. The most predominant Giardia assemblage isolated was the livestock specific assemblage E (89%). The zoonotic assemblages A and B were found in 4 and 7% of the Giardia isolates that were genotyped, respectively. The Giardia assemblages were detected equally between the cows and calves examined. Overall, the most common Cryptosporidium species detected in this study was Cryptosporidium andersoni (49%), predominantly found in cattle >6mo of age, while most Cryptosporidium bovis and Cryptosporidium pestis (previously Cryptosporidium parvum ‘bovine genotype’) isolates were detected in calves≤6mo of age. All Cryptosporidium ryanae isolates (four) were found in calves. Giardia cysts and Cryptosporidium oocysts were detected in 14 and 93% of surface water samples of 14 farms, respectively. Cryptosporidium oocysts were detected in three (15%) ground water samples of 20 farms. One Cryptosporidium-positive water sample, which was the only surface water sample amenable to genotyping, contained C. parvum. The farm-level risk factors investigated in this study, age of animals and location of the farm, were not associated with the risk of infection in cattle with either Cryptosporidium spp. or Giardia duodenalis. We conclude that beef cattle are a potential reservoir of Cryptosporidium spp. and G. duodenalis that could contaminate source water. There is the possibility of further transmission to humans on PEI if the source water is not properly treated prior to consumption. [Copyright &y& Elsevier]

The article presents a study which determines the genotypes and prevalence of Giardia duodenalis in beef and dairy cattle in farms in Charlottetown, Prince Edward Island. The study used RNA sequencing, immunofluorescence, and polymerase chain reaction (PCR). Results show that the prevalence rates were 40% and 41% for cows in tie- and free-stall herds, while 27% in beef cattle.

Food and waterborne protozoan pathogens including Cryptosporidium parvum , Giardia enterica and Toxoplasma gondii are a global concern for human public health. While all three pathogens have been detected in commercial shellfish, there is currently no standard approach for detecting protozoan parasites in shellfish. Common molecular and microscopic methods are limited in the number of pathogens they can simultaneously detect and are often targeted at one or two of these pathogens. Previously, we developed and validated a novel 18S amplicon-based next-generation sequencing assay for simultaneous detection of Cryptosporidium spp., Giardia spp. and T. gondii in shellfish. In this study, we applied the assay for protozoan pathogen detection in wild oysters from Prince Edward Island (PEI). Oysters were harvested from restricted and prohibited areas, classified by the Canadian government according to fecal coliform counts in surrounding waters, and different fractions (whole tissue homogenate and hemolymph) were analyzed. Protozoan DNA was detected using metabarcoding in 28%, of oysters tested (N = 128), and the pathogen read counts in oyster homogenate were considerably higher than those in hemolymph. Protozoan read count thresholds were established for classifying probable oyster contamination with pathogens to account for low levels of background protozoan reads detected in negative controls. Assay results showed protozoan contamination was not associated with harvesting site classifications, suggesting that using fecal indicators for ensuring food safety may be insufficient. Due to the complex matrix, an oyster DNA reduction step may further improve the pathogen detection sensitivity of the assay. Results from this study affirm that novel metabarcoding is a promising screening tool for detection of protozoan pathogens in shellfish. • Protozoan pathogens were detected in wild oysters using a novel 18S based NGS assay. • Protozoan contamination was not associated with shellfish harvesting zones. • Protozoan read levels in oyster homogenates were higher than in hemolymph. [ABSTRACT FROM AUTHOR]

Objective: Molecular identification of small cestodes, morphologically consistent with Echinococcus multilocularis , recovered at necropsy from the gastrointestinal tract contents of a red fox, was accomplished by PCR using published species-specific n ad1 primers and methods., Animal: Red fox (Vulpes vulpes) ., Procedure: Small cestodes recovered from intestinal contents of a red fox trapped on Prince Edward Island in December 2020 (frozen at -20°C before being processed for parasite recovery in June 2021) were morphologically identified. Species identity confirmation and haplotyping of the cestodes were done via PCR and DNA sequencing of the n ad1, nad2 , and cob genes., Results: Small cestodes morphologically consistent with E. multilocularis were detected in the gastrointestinal tract contents of a red fox trapped near Montague, PEI. The species identity was confirmed via PCR. Haplotyping revealed that they were of the European E1 haplotype., Conclusion: In Canada, E. multilocularis has been reported as far east as Québec, with most reports being in central and western provinces and territories. This is the first report of E. multilocularis infection in a canid host east of Ontario, Canada and illustrates the need for regular wildlife disease surveillance to enhance our understanding of emerging pathogens of veterinary and medical importance., Clinical Relevance: Echinococcus multilocularis is a highly pathogenic zoonotic cestode from the family Taeniidae that can cause alveolar echinococcosis (AE) when rodents, dogs, horses, pigs, non-human primates, or humans ingest its eggs. Alveolar echinococcosis is challenging to treat, and survival rates for untreated individuals are low., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Objective: To identify first-stage nematode larvae (L1) recovered from a red fox scat sample and adult female worms recovered from 2 red fox lungs at necropsy, using published molecular methods to confirm a morphological diagnosis of Angiostrongylus vasorum (French heartworm)., Animal: Red fox (Vulpes vulpes) ., Procedure: Nematode larvae recovered from a Baermann examination survey of wild canid scats ( n = 101) conducted from January 2017 to August 2020, were identified by size and morphology and subjected to PCR and DNA sequencing of the small subunit (SSU) rRNA gene, the large subunit (LSU) rRNA gene, or the second internal transcribed spacer (ITS2). In addition, these techniques were applied to adult female worms recovered from the heart/lungs of 2 red foxes (obtained from PEI trappers and stored frozen at -20°C since December of 2018 and 2020)., Results: Size and morphology of L1 recovered by Baermann examination from a wild canid scat sample (presumed to be red fox) collected near Montague, PEI and adult female worms recovered at necropsy from 2 red fox carcasses were identified as A. vasorum . Molecular analysis confirmed the larvae and adult worms were A. vasorum ., Conclusion: These findings indicated that A. vasorum has become endemic in the red fox population on PEI., Clinical Relevance: Angiostrongylus vasorum infection is potentially fatal in dogs. Veterinarians and regional diagnostic laboratories in the Maritime provinces should consider the possibility of A. vasorum infection in dogs with clinical signs of cardiopulmonary and/or central nervous system disease or bleeding disorders., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Although many studies on the frequency of endoparasites in dogs and cats in Canada have been reported, seasonal and/or annual patterns are often not evaluated. The frequency and risk factors of endoparasite infections from fecal samples of cats and dogs submitted to the Veterinary Teaching Hospital of the Atlantic Veterinary College, University of Prince Edward Island-Canada were determined, using univariable and multivariable logistic regression analyses. Investigated predictors of endoparasitism available in the 2000-2017 database included sex, age, geographic origin and seasonality. A total of 15,016 dogs and 2,391 cats were evaluated for endoparasite status using specific diagnostic tests: direct smear, Baermann, and/or 33 % zinc sulfate solution in a standardized centrifugal flotation method. Overall, twelve and eight parasite genera were detected in dogs and cats, respectively. The overall proportional infection was 14.6 %, and the cat population showed a higher frequency of positivity to parasites compared to the dog population (P < 0.001). The most frequent genera recovered in the whole population (dogs and cats), were Giardia duodenalis (5.2 %), Cystoisospora spp. (3.3 %) and Toxocara spp. (3.2 %). Endoparasitism levels were diagnosed more in feces submitted from young, female intact dogs from PEI compared to the baselines of mature, sterilized male dogs from other provinces, respectively, and diagnoses occurred more often in autumn months than in winter months. There was no significant diagnostic trend across the years for the individual parasites models. The frequency of detected potentially zoonotic parasites in this study highlights the veterinary public health and One Health context of parasitic infections in pets. Although the presented results are not from a random sample and therefore frequency results should be interpreted with caution, the model relationship results may still be relevant. In addition, results are of value to estimate parasite impact and to assist researchers, veterinarians and pet-owners with suitable information to control parasites., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Prevalence of Giardia duodenalis in dairy and beef cattle on farms around Charlottetown, Prince Edward Island (Canada) was determined by analyzing feces using direct immunofluorescence antibody microscopy. Genotypes were determined by 16S-rRNA sequencing. Fecal samples (n = 892) were collected from adult cattle in dairy tie-stall, dairy free-stall, and beef herds (10 herds each), and from calves (n = 183) from 11 dairy farms. Prevalence rates were 38% and 51% in cows and calves, respectively. Giardia duodenalis was present in all dairy herds, in 9/10 beef herds and in calves from 10/11 herds examined. Prevalence rates were 40% and 41% for cows in tie- and free-stall herds, respectively, and 27% for beef cows. Zoonotic Assemblage A was found in 12.2% of calves concomitantly infected with Assemblage E. All successfully sequenced samples (114/128) from cows corresponded to Assemblage E. Giardia duodenalis is highly prevalent in cattle herds in Prince Edward Island and Assemblage A in calves is a potential public health concern.