Veterinary parasitology最新文献

Otodectes cynotis is a contagious ear mite generally responsible of a parasitic otitis. This prospective study evaluates the efficacy, safety and impact on quality of life (QoL) of oral lotilaner for the treatment of Otodectes infestation in ferrets. Ferrets of weight greater than 500 g, with Otodectes mites confirmed on ear swabs examination and that did not receive an acaricidal treatment in the previous two weeks were included. Oral lotilaner (Credelio 12 mg, ELANCO FRANCE, Sèvres, France) was administered at inclusion day (D0) and 28 days later (D28). Parasitic counts and clinical examination were performed at D0, D28 and D56. A QoL and owner satisfaction questionnaire was given at D0 and D56. Statistical analysis was performed with Shapiro-Wilk test for normality and Wilcoxon test for mean comparison (significance: p<0.05). Eleven ferrets were included, two were asymptomatic. Mean weight was 1.2 kg (0.68–2.66). Mean lotilaner dose was 12.3 mg/kg (9–17.6). Mean eggs, adults or nymphs, larvae, and fragments counts were 30.4 (3–104), 11.2 (1–61), 5.4 (0–36), 3.5 (1–7) respectively at D0; 0, 0, 0.1 (0–1), 0.5 (0–3) respectively at D28; 0, 0, 0, 0.14 (0–1) respectively at D56. Differences were statistically significant from baseline in all cases (p<0.05). Pruritus was absent in all cases at D56. No adverse effects were reported. All owners were “completely satisfied” with the treatment. Mean impact of the disease on QoL was 4.5/18 (SD=4.15) at D0 and 0 at D56 (significant difference, p<0.05). Oral lotilaner appears as a safe, efficient, easy to use and satisfactory treatment of Otodectes cynotis infestation in ferrets.

Babesia and Theileria species (Apicomplexa: Piroplasmida) are tick-borne protozoan parasites that can cause mild to severe infection in humans, wildlife, livestock and companion animals. To date, reports on the molecular study of piroplasms from wild living small mammals and their ticks are still limited, especially in Asia. This study encompassed an extensive survey involving 907 liver samples and 145 ixodid ticks from 16 different species of small mammals (Rodentia, Lagomorpha, Eulipotyphla). These were collected in 13 cities and counties in northern China. DNA extracts from these samples were screened for the presence of piroplasm 18S rRNA gene. Samples that tested positive were further evaluated for other genetic markers of piroplasms, including the cox1 gene and the ITS1-5.8S rDNA-ITS2 region. Several piroplasm species were identified, including Babesia sp. tavsan2, Babesia occultans, Theileria sp. Xinjiang, Theileria equi, and Theileria sp. Kalecik. Among these, Theileria sp. Xinjiang was shown to be the most prevalent. Importantly, Babesia sp. tavsan2 was identified in the tick Rhipicephalus sanguineus from the Yarkand hare and Theileria sp. Kalecik in Hyalomma asiaticum from the long-eared hedgehog, in line with the detection of these pathogens in tissue samples of the relevant hosts. This study further disclosed the presence of DNA from B. occultans and T. equi, typically found in cattle and horses respectively, with an additional discovery in small mammals. Moreover, Theileria sp. Kalecik, which was first detected in small-sized mammals, and Babesia sp. tavsan2, were both reported for the first time in China.

Toxoplasmosis caused by Toxoplasma gondii is a protozoal zoonosis with high sanitary risk for pregnant women and immunocompromised people. Felids, including domestic cats, are the only definitive hosts of T. gondii. They shed oocysts which, in the environment, become infectious for a wide range of animals, including humans, acting as intermediate hosts. This study evaluated the frequency of acute toxoplasmosis in domestic cats with compatible clinical signs and living in households with women of childbearing age. Individual serum samples were collected from 150 cats and analyzed for IgM and IgG against T. gondii. Statistical analyses were performed to evaluate associations between seropositivity and potential risk factors. Overall, 31 cats (20.7 %) were seropositive for anti-T. gondii antibodies, i.e. 9 (6.0 %) for IgM, 17 (11.3 %) for IgG and 5 (3.3 %) for both. The cats showed different combinations of clinical pictures. The following statistically significant associations were found: male sex and positivity for IgM and/or IgG (p=0.0248; OR= 0.3537; 95 % CI= 0.1528–0.8675), presence of 2 or more clinical signs and positivity to IgM only (p=0.0003; OR= +infinity; 95 % CI= 3.924 to +infinity), presence of either neurological signs (p=0.0025; OR= 13.30; 95 % CI= 3.409–61.39) or ocular signs (p=0.0228; OR= 5.835; 95 % CI= 1.631–22.37) and positivity to IgM only, presence of gastrointestinal signs and positivity to IgG only (p=0.0083; OR= 5.508; 95 % CI= 1.503–18.54). Male sex also resulted a possible risk factor in the binomial logistic regression (p= 0.011; OR= 3.336; 95 % CI= 1.131–8.44). These results indicate that cats living with women of childbearing age are at risk of infection with T. gondii. The presence of certain clinical signs can be helpful in identifying recent and/or current infections using laboratory analyses. Awareness on toxoplasmosis should be kept high to protect animal and public health.

The liver fluke Fasciola hepatica is a trematode parasite of farmed livestock with worldwide distribution, causing chronic production losses and possible death from hepatobiliary damage. The effective management of liver fluke infection requires diagnostic tests which can accurately identify infected animals at both the individual and herd level. However, the accuracy of liver fluke diagnostic tests performed on individual New Zealand cattle is currently unknown. The aim of this study was to use a Bayesian latent class model (LCM) to estimate the test characteristics of three liver fluke diagnostic tests, the coproantigen ELISA, the IDEXX antibody ELISA and the faecal egg count. One hundred and twenty dairy cows each from two dairy farms were blood and faecal sampled in April 2021. The samples were transported to Massey University, Palmerston North, and the three diagnostic tests completed following the respective manufacturer instructions. A Bayesian LCM model, adapted from the original Hui and Walter 2 tests 2 populations model, was built to estimate the test characteristics of the three diagnostic tests in the two dairy herds. The model was implemented in JAGS using Markov chain Monte Carlo sampling. The first 30,000 iterations were discarded as burn-in, and the next 200,000 iterations were used to construct the posterior distributions. Uninformed priors, beta (1,1), were used as the prior distributions for the prevalence estimation and informed beta priors, based on published results, were used as the prior distributions for estimating the sensitivity and specificity of each diagnostic test. Model convergence was confirmed by inspection of trace plots and examination of the results of the Gelman and Rubin test. The results found that the coproantigen ELISA test was the most accurate for diagnosing liver fluke infection in individual animals with a sensitivity = 0.98 (95 % CI 0.95–1.00) and specificity = 0.95 (95 % CI 0.81–1.00) compared to the IDEXX antibody ELISA test, sensitivity = 0.39 (95 % CI 0.32–0.47) and specificity = 0.86 (95 % CI 0.75–0.96) or the FEC, sensitivity = 0.23 (95 % CI 0.17–0.30) and specificity = 0.92 (95 % CI 0.86–0.97). Based on these results clinicians should be encouraged to use the coproantigen ELISA test to diagnose liver fluke infection in individual cattle.

The cuttlefish Sepia pharaonis species complex is emerging as a promising set of organisms for research in neuroscience, the behavioral sciences, and commercial aquaculture. At the same time, information about pathogens and diseases that could affect cuttlefish cultivation in intensive aquaculture settings remains limited. Our study has identified two species of parasite, the protozoan Liburna oophaga sp. nov. and the metazoan Ikanecator primus, that co-infect cuttlefish eggs, increasing mortality and reducing hatching rates. L. oophaga sp. nov. is reported here for the first time to enhance mortality during the incubation period by inducing deformity in cuttlefish eggs. We investigated the application of peracetic acid to parasite elimination during cuttlefish egg incubation. When cuttlefish eggs were treated with a peracetic acid containing product (PAA-product); 35 mg/L PAA + 15 mg/L H₂O₂, L. oophaga on the surfaces of the eggs were eliminated within 10 min. PAA-product; 70 mg/L PAA + 30 mg/L H₂O₂ was required to achieve the same effect for I. primus. Immersion treatment with PAA-product at 70 mg/L PAA + 30 mg/L H₂O₂ reduced parasitic load and improved survival of cuttlefish embryos and hatchling size, demonstrating that PAA product can inhibit and control parasitic co-infections in cephalopod culture.

To minimize the damage caused by synthetic acaricides to non-target organisms, the use of bioactives compounds extracted from plants has been considered. In this study, semi-engorged females of Rhipicephalus linnaei ticks were exposed to Cannabis sativa flower extract (submersion for 5 minutes in different concentrations diluted in ethanol 30 %) evaluated alterations in the integument and salivary glands. The results demonstrated that lower concentrations of the extract caused damage to both the integument and salivary glands, affecting the cuticular epithelial cells responsible for synthesizing all layers of the cuticle. The concentration of 2.5 mg/mL caused more extensive damage than 5.0 mg/mL, and 40 mg/mL completely disrupted the epithelium. Exposure of the salivary glands showed that at 2.5 ug/mL dose the glandular acini was disrupted, leaving only a heterogeneous mass with some nuclei of acinar cells, leading to acinar rupture. These findings indicate that the extract from Cannabis sativa flowers irreversibly alters the morphology and consequently, interferes with the functionality of different vital organs.

Eimeria spp. are important coccidian parasites causing diarrhea and significant mortality in cattle worldwide. To date, at least 13 Eimeria species with varying pathogenicity have been identified in cattle. Efficient detection and identification of Eimeria spp. is therefore essential for the prevention and control of bovine coccidiosis. However, the commonly used microscopic examination for Eimeria spp. is time-consuming and requires considerable expertise. In this study, we aligned the nucleotide sequences of the small subunit (SSU) rRNA gene of common Eimeria species and developed a nested PCR assay targeting the polymorphic SSU rRNA region of Eimeria spp. from cattle. Initially, the SSU rRNA gene PCR assay was compared with microscopic examination for sensitivity and detection range of Eimeria species using fecal samples from dairy cattle. Of the 193 fecal samples, 131 (67.9 %) and 78 (40.4 %) were positive for Eimeria by PCR and microscopy, respectively. Sequence analysis of the PCR products identified six Eimeria species, including E. cylindrica (n = 76), E. bovis (n = 54), E. auburnensis (n = 30), E. zuernii (n = 25), E. wyomingensis (n = 10), E. canadensis (n = 1), and co-infections of 2–4 species (n = 55). In contrast, only the first four species and co-infections of 2–3 species were identified by microscopy. The PCR assay was able to detect as few as 50 Eimeria oocysts per gram of feces. Thus, the developed SSU rRNA gene PCR assay has a high sensitivity and allowed easy identification of at least six common Eimeria species and their co-infections in cattle. It should be useful in molecular epidemiological studies of bovine coccidiosis.

The primary aim of this study was to compare the in vivo responses to orally administered doses of albendazole (5 mg/kg body weight) between experimentally infected sheep and goats. Fifty-four Improved Valachian lambs and 54 Saanen goat kids were split into six groups of nine animals. The sheep and goats were infected with larvae of the gastrointestinal nematode parasite Haemonchus contortus containing 10, 20, 30, 40, 60, and 80 % of the isotype-1 β-tubulin gene codon 200 alleles previously shown to be associated with benzimidazole (BZ)-resistance. All groups of goats generally had higher mean eggs per gram (EPG) before treatment, which was significant (p<0.05) only for the group with 80 % resistance alleles. An in vivo faecal egg reduction test (FECRT) was used to determine the efficacy of albendazole (ABZ) eight days after treatment. Anthelmintic treatment significantly reduced the EPGs in the groups with 10, 20, and 80 % resistance alleles in sheep and with 10, 20, 30, and 40 % resistance alleles in goats. Differences in efficacy between the sheep and goats after the application of doses of ABZ recommended for sheep mostly ranged from 2 % to 10 %. The largest variation was in the group infected with worms containing 60 % resistance alleles, where the efficacy was 13 % higher in goats. Our secondary aims were to evaluate the data obtained from an in vitro egg hatch test (EHT) in sheep and goats and to compare these data with the results from the isotype-1 β-tubulin gene codon 200 pyrosequencing and the FECRT. The percentages of the BZ-resistance alleles were comparable with the mean hatching obtained in the EHT and were also supported by the FECRT data for all groups. The results of the in vivo tests should be verified in the future using in vivo surveys conducted in mixed breeds and infections in multiple species.