Veterinary Parasitology: X最新文献

{"title":"Trichinella spiralis - New method for sample preparation and objective detection of specific antigens using a chemiluminescence immunoassay.","authors":"Jana Braasch, Stefanie Ostermann, Monika Mackiewicz, Catherine Bardot, Caroline Pagneux, Viola Borchardt-Lohölter, Erik Lattwein","doi":"10.1016/j.vpoa.2020.100033","DOIUrl":"10.1016/j.vpoa.2020.100033","url":null,"abstract":"<p><p>The parasitic roundworm <i>Trichinella spiralis</i> is most commonly transmitted to humans through consumption of raw or undercooked meat of infected pigs or game. To prevent human infection, slaughterhouses perform meat safety surveillance using the gold standard \"Magnetic Stirrer Method\". We introduce a fast and objective method using automated detection of specific <i>Trichinella spiralis</i> antigens by a newly developed immunoassay based on chemiluminescence (ChLIA). Panel A comprised muscle tissue samples from non-infected pigs (n = 37). Panel B comprised muscle tissue samples from non-infected pigs spiked with different amounts of <i>Trichinella</i> larvae without collagen capsules (n = 56). Panel C contained muscle tissue samples from experimentally infected pigs including <i>Trichinella</i> larvae encapsulated in collagen (n = 32). Each sample was shredded with PBS buffer in a knife mill, destroying <i>Trichinella</i> larvae. Following centrifugation, the supernatant (muscle tissue extract containing released excretory and secretory <i>Trichinella spiralis</i> antigens) was used for <i>Trichinella-</i>specific antigen detection by the new Trichinella ChLIA. The overall accuracy of the Trichinella ChLIA was 97.6 %. The specificity of the Trichinella ChLIA was 100 % (panel A). The sensitivity in samples from experimentally infected pigs was 100 % representing a detection limit of 0.01 larvae per gram. Cross-reactivity with parasites other than <i>Trichinella spp</i>. was not observed. This new meat inspection method for the detection of <i>Trichinella spiralis</i> antigens presents high specificity and high sensitivity, especially in truly infected samples. In contrast to the gold standard, this new approach to meat safety surveillance does not require longsome digestion or microscopy by trained personnel.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"4 ","pages":"100033"},"PeriodicalIF":0.0,"publicationDate":"2020-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7711141/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141890240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of a topical combination of eprinomectin, praziquantel, fipronil and (S)-methoprene against developing and adult <i>Troglostrongylus brevior</i> lungworms (Nematoda, Crenosomatidae) in cats.","authors":"Martin Knaus, Martin Visser, Sandra Mayr, Steffen Rehbein","doi":"10.1016/j.vpoa.2020.100032","DOIUrl":"https://doi.org/10.1016/j.vpoa.2020.100032","url":null,"abstract":"<p><p>The efficacy of the eprinomectin, praziquantel, fipronil and (S)-methoprene combination parasiticide Broadline® (Boehringer Ingelheim Animal Health) was evaluated against developing larval and adult stages of <i>Troglostrongylus brevior</i>, a metastrongyloid pulmonary nematode which is reported to parasitize domestic cats in southern Europe with increasing frequency. Twenty four purpose-bred cats were experimentally infected with 100 third-stage <i>T. brevior</i> larvae each and randomly allocated to either remain untreated (control) or to be treated with the combination product when <i>T. brevior</i> were developing larval (6 days post inoculation, dpi) or adult nematodes (28 dpi) (eight cats per group). Treatments were administered topically at the minimum label dose of 0.12 mL/kg. Fecal samples of the cats were examined to confirm the presence of patent (adult) nematode infections prior to treatment at 28 dpi and to monitor the larval excretion. At necropsy (49 dpi), the weight of the pulmonary lymph nodes and lungs were determined, and <i>T. brevior</i> lungworms were recovered and counted. All control animals and cats to be treated at 28 dpi excreted <i>T. brevior</i> larvae 24 dpi and 26 dpi while no larvae were excreted by the cats treated at 6 dpi. Following treatment at 28 dpi, <i>T. brevior</i> larval excretion decreased immediatetly and ceased prior to necropsy. Nematode counts demonstrated that treatment with the combination product was 100 % efficacious against both developing larval and adult <i>T. brevior</i>: no lungworms were recovered from any treated cat while all control animals harbored <i>T. brevior</i> (range, 6-52) (p < 0.001). No treatment-related health problems or any other clinical signs were observed in the cats. However, significantly higher absolute and relative (organ weight to body weight ratio) pulmonary lymph node weights of the control animals compared with the treated cats at 6 dpi (p < 0.001 and p < 0.001, respectively) and at 28 dpi (p = 0.003 and p = 0.019, respectively) indicated the pathology of the <i>T. brevior</i> infection. In conclusion, the combination product was demonstrated to be 100 % efficacious against developing larval and adult <i>T. brevior</i>. Furthermore, it was demonstrated that indicators of impaired respiratory and immune systems resultant from <i>T. brevior</i> infection can be prevented with an efficacious treatment when administered during the pre-patent period of infection or are improving substantially within three weeks of treatment of cats harboring adult lungworms.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"4 ","pages":"100032"},"PeriodicalIF":0.0,"publicationDate":"2020-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7554208/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149018000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combined cross-sectional and case-control study on <i>Echinococcus multilocularis</i> infection in pigs in Switzerland.","authors":"Anika Meyer, Philipp Olias, Gertraud Schüpbach, Martin Henzi, Thomas Barmettler, Brigitte Hentrich, Bruno Gottstein, Caroline F Frey","doi":"10.1016/j.vpoa.2020.100031","DOIUrl":"10.1016/j.vpoa.2020.100031","url":null,"abstract":"<p><p>The canid tapeworm <i>Echinococcus multilocularis</i> causes alveolar echinococcosis (AE) in humans and other intermediate hosts. Depending on the permissiveness of the intermediate host, the larval form of <i>E. multilocularis</i> (metacestode) may be either fertile, e.g. in rodents, and thus supporting the life cycle of the parasite, or infertile, e.g. in pigs, and thus interrupting the life cycle. Pigs have been shown to act as aberrant hosts for the metacestode and consequently develop liver lesions but represent a dead-end for the parasite. Routine liver inspection at slaughter provided the basis for a large-scale surveillance study on <i>E. multilocularis</i> infection in pigs. The aim of this combined cross-sectional and case-control study was to estimate the minimal prevalence of <i>E. multilocularis</i> in pigs in Switzerland, to find factors associated with infection, and to assess potential regional clusters of infection. During the 12-month-study period, approximately 85% of all pigs slaughtered in Switzerland were assessed. In total, 450 pig livers with macroscopic lesions suggestive of <i>E. multilocularis</i> infection were analysed. Of those, 200 samples were positive by <i>E. multilocularis</i>-PCR. Thus, the overall minimal prevalence detected by molecular means was 0.009% in all slaughter pigs (200 of 2'143'996), 0.008% in finishing pigs (177 of 2'123'542), and 0.11% in breeding pigs (22 of 20'454). Histology revealed the unique presence of a laminated layer in 105 cases, and an additional germinal layer detected in a single case. Protoscoleces could not be observed in any of the lesions. Factors positively associated with infection were \"foxes seen in the pig shed\", \"foxes on premises\", \"presence of other animals in the shed\", \"absence of a hygiene barrier\", \"outdoor feeding\", \"feeding grass\", \"lack of rodent control\", \"not having own dogs on the farm\" and \"infrequent deworming of sows\". Infection was present in all regions sampled and was representative of the important pig rearing areas of Switzerland, without evidence of any obvious geographical cluster. Conclusively, our study provided further evidence of widespread environmental contamination with <i>E. multilocularis</i> eggs in Switzerland. Furthermore, the absence of protoscoleces in any of the lesions supported the concept that pigs act only as a dead-end host and thus do not contribute to the life cycle of the parasite. Factors associated with <i>E. multilocularis</i> infection were in-line with parasite biology, and many can be addressed by increasing hygiene and management standards.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"4 ","pages":"100031"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7491148/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147718365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potentials of using milk performance data and FAMACHA score as indicators for Targeted Selective Treatment in Lacaune dairy sheep in Switzerland.","authors":"Katharina Schwarz, Beat Bapst, Mirjam Holinger, Susann Thüer, Inga Schleip, Steffen Werne","doi":"10.1016/j.vpoa.2020.100030","DOIUrl":"10.1016/j.vpoa.2020.100030","url":null,"abstract":"<p><p>Targeted Selective Treatment (TST) is one approach to slow down the development of anthelmintic resistance. Its success is closely linked to the correct identification of animals in need of treatment. In dairy goats it has been proposed to use milk yield as TST indicator and to focus treatments on high yielding dairy goats. In dairy sheep the relationship between milk performance and infection with gastrointestinal nematodes (GIN) is not well known. The aim of this study was to investigate the relationship between milk yield and GIN infection in dairy sheep and based on this, to evaluate milk performance data as a potential TST indicator. Overall 1159 Lacaune ewes of 15 dairy sheep farms in Switzerland were included in the study. The ewes were phenotyped once between August and December 2019, when they were at least 70 days in milk (DIM). Individual faecal samples were taken from every ewe to determine the nematode egg concentration per gram faeces (EPG). In addition, the clinical parameters FAMACHA score and packed cell volume (PCV) were measured. Linear mixed models were used to analyse the effects of the collected parameters on EPG. EPG increased significantly with increasing test day milk yields (P = 0.002), indicating high yielding ewes to be less resistant to GIN infections than low yielding ewes. The effect was most pronounced in earlier lactation but remained within a moderate range. Overall, our results indicated the potential of using milk yield data of rather early lactation as TST indicator in dairy sheep. On farms with predominantly <i>H. contortus</i> the combination with FAMACHA might improve the correct identification of highly infected ewes, as FAMACHA was correlated with EPG (r = 0.37, P < 0.001).</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"4 ","pages":"100030"},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7494794/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140319282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New insights into the biology, diagnosis and immune response to <i>Dirofilaria repens</i> in the canine host.","authors":"L Ciuca, A Vismarra, W Lebon, F Beugnet, R Morchon, L Rinaldi, G Cringoli, L Kramer, M Genchi","doi":"10.1016/j.vpoa.2020.100029","DOIUrl":"https://doi.org/10.1016/j.vpoa.2020.100029","url":null,"abstract":"<p><p>Dogs are the primary host for <i>Dirofilaria repens</i>, therefore it is mandatory to accurately diagnose the canine infection and to expand our current knowledge on parasite biology and the immune response of the infected host for a better prevention.Thus, the aim of the present study was to provide new insights from experimental infections of dogs with <i>D. repens</i>, focusing on the evaluation of: 1) the pre-patent period and 2) the antibody response against <i>D. repens</i> somatic antigens and against the <i>Wolbachia</i> endosymbiont. Briefly, on Day 0, twenty purpose-bred Beagle dogs were experimentally infected with 50 infective larvae (L3) of <i>D. repens</i>. Starting from Day 58 until the last day of the study (Day 281), blood samples were collected on a monthly basis for detection of antibodies against <i>D. repens</i> (Dr) and recombinant <i>Wolbachia</i> surface protein (rWSP) by non-commercial IgG-ELISAs. Additional samples were collected on Days 220, 245 and 281 for the detection of microfilariae (mff) using the modified Knott's test and biomolecular analysis, following two PCR protocols: Gioia et al. (2010; protocol A) and Rishniw et al. (2006- protocol B). The results were analysed by univariate statistical analyses using 2 × 2 contingency tables and K Cohen was calculated to assess the agreement among all the diagnostic techniques. Overall, the outcome of the study revealed that out of the 20 dogs experimentally infected with <i>D. repens</i>, 16 (80 %) were microfilaraemic, 17 (85 %) were positive at DNA detection in the blood, 18 (90 %) had <i>D. repens</i> antibodies and 16 (80 %) had <i>Wolbachia</i> antibodies on the last day of the study. The overall k agreement between Knott's and PCR protocol B was 0.442 (P = 0.0001) and increased throughout the study, reaching 0.828 (P = 0.0001) on Day 281. To the authors knowledge, this is only the second study reporting antibody response to <i>D. repens</i> somatic antigen in experimentally infected dogs. ELISA results showed that an antibody response develops before the onset of patency, and steadily increases with time. Results would suggest that the development of an immunological response to infection could lead to application in epidemiological studies, risk assessment and as an aid in the diagnostic approach in dogs, in particular for early infections without mff.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"4 ","pages":"100029"},"PeriodicalIF":0.0,"publicationDate":"2020-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7458378/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149017959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heartworm prevalence in dogs versus cats: Multiple diagnostic modalities provide new insights.","authors":"Kellie M Hays, Jessica Y Rodriguez, Susan E Little, Annette L Litster, Kennedy K Mwacalimba, Kellee D Sundstrom, Deborah M Amodie, Maria A Serrano, Simone D Guerios, Jennifer N Lane, Julie K Levy","doi":"10.1016/j.vpoa.2020.100027","DOIUrl":"https://doi.org/10.1016/j.vpoa.2020.100027","url":null,"abstract":"<p><p>The cornerstones of diagnosis of heartworm (HW) in dogs are the detection of circulating antigen from adult female <i>Dirofilaria immitis</i> or the visualization of microfilariae in whole blood. These tests are less sensitive in cats because of the feline immune response leading to low numbers of adult worms, but heartworm antibody tests are also licensed for use in cats. HW antibodies in cats are detectable when there has at least been larval development in the tissues, but positive antibody tests cannot distinguish between current and previous larval infections; thus, cats with positive antibody test results are considered currently or previously infected with <i>D. immitis</i>. The aim of the present study was to use multiple HW diagnostic modalities to maximize detection of infection in dogs and cats at high risk of infection and to compare infection prevalence between these two hosts. Blood samples collected from 100 stray dogs and 100 stray cats at Florida animal shelters were tested for HW antigen (before and after heat treatment) and microfilariae; cats were also tested for HW antibody. Dogs were significantly (<i>P</i> = 0.0001) more likely to be diagnosed with adult HW infection (28 %; 95 % CI: 20.1-37.6%) when compared with cats (4 %; 95 % CI: 1.6-10.2%) on the basis of positive antigen and microfilariae test results. Cats with current or previous adult, immature adult, or larval HW infections comprised 19 % (95 % CI: 12.4%-27.9%) of the feline population, which was not significantly different (<i>P</i> = 0.1) from the prevalence of adult <i>D. immitis</i> infection in dogs. Testing unprotected cats for heartworm antibodies demonstrated a similar, high risk of infection to the matched unprotected dog population in Florida, which supports the use of HW preventives in cats in areas where HW transmission occurs.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"4 ","pages":"100027"},"PeriodicalIF":0.0,"publicationDate":"2020-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7458388/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149018019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental assessment of permethrin-fipronil combination in preventing <i>Leishmania infantum</i> transmission to dogs under natural exposures.","authors":"Elias Papadopoulos, Athanasios Angelou, Maxime Madder, Wilfried Lebon, Frederic Beugnet","doi":"10.1016/j.vpoa.2020.100026","DOIUrl":"https://doi.org/10.1016/j.vpoa.2020.100026","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Canine vector-borne disease transmission can be reduced with regular use of repellent insecticides. The objective of this year-long experimental study was to assess the efficacy of a topical formulation of fipronil/permethrin (Frontline Tri-Act®) in preventing transmission of &lt;i&gt;Leishmania infantum&lt;/i&gt; by sandflies. This clinical field trial was conducted in Xanthi (Northern Greece), an area highly endemic for canine leishmaniosis, from April 2018 to March 2019. Forty purpose-bred Beagle dogs, testing negative for &lt;i&gt;L. infantum&lt;/i&gt; prior to study initiation, were enrolled in the study, which consisted of three phases: Phase 1 (field exposure phase) took place from Day 0-196. The dogs were randomly allocated to two groups, group 1 (sham-treated topically with sterile water) and group 2 (treated topically with Frontline Tri-Act®). Dogs in both groups were housed in two subunits of an open-air kennel for a period of 7 months, spanning the &lt;i&gt;Leishmania&lt;/i&gt; transmission season. All dogs were treated or sham-treated on Days 0, 28, 56, 84, 112, 140 and 168. Clinical examinations, PCR analysis of conjunctival swabs, and serological tests were performed on a monthly basis. Sandflies were collected every 2 weeks, during a 12 -h period overnight using light traps. Each collection was placed in a container and kept refrigerated until speciation and PCR analysis could be performed. In the second phase of the study, from Day 197 to 252, the dogs were moved into a protected environment (insect-proof protected environment phase). CDC light traps were activated every 2 weeks inside and outside the kennels to ensure the vector-free status of the facility. Monthly clinical examinations, including PCR analysis of conjunctival swabs, and serological tests continued. At the end of the phase 2, bone marrow samples were collected on all dogs. Phase 3 (the final post-winter check) took place from Day 253 to 350. Dogs were released and adopted by individual private owners on Day 253. Follow up analyses included blood collection for SNAP tests and conjunctival swaps for PCR analysis on Days 304 and 350. Additionally, bone marrow collections were also performed on Day 350. Presence of sandflies was observed only in the phase 1 exposure period, and 1714 sandflies were collected (1427 females and 287 males). Two species were identified, &lt;i&gt;Phlebotomus perniciosus&lt;/i&gt; var&lt;i&gt;. tobbi&lt;/i&gt; and &lt;i&gt;Phlebotomus neglectus&lt;/i&gt;. Out of the 62 pooled samples of sandflies assessed by PCR, three were considered positive (4.8 %). By the end of the study, 35 % of the Group 1 dogs (7/20) became positive based on PCR (conjunctival swab and bone marrow) and 30 % (6/20) based on SNAP/IFAT and ELISA tests, while all the dogs in the Frontline Tri-Act® treated group 2 remained negative for all tests (G1 vs G2, p = 0.008). All tests identified the same positive animals, and PCR allowed the detection of one additional infected dog. This clinical field trial demonstrated that monthly administr","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"3 ","pages":"100026"},"PeriodicalIF":0.0,"publicationDate":"2020-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7458379/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149017938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of Broadline® in cats against induced infections with developing fourth-stage larval and adult <i>Ancylostoma ceylanicum</i> hookworms.","authors":"Martin Knaus, Piyanan Taweethavonsawat, Tara Cheesman, Martin Visser, Steffen Rehbein","doi":"10.1016/j.vpoa.2020.100025","DOIUrl":"https://doi.org/10.1016/j.vpoa.2020.100025","url":null,"abstract":"<p><p><i>Ancylostoma</i> <i>ceylanicum</i> hookworms parasitize dogs and cats in subtropical and tropical South East Asia and Pacific region, the Arab Peninsula, southern Africa and South America but cause patent infections in humans too. To evaluate the efficacy of Broadline®, a combination product comprising eprinomectin, fipronil, (S)-methoprene and praziquantel, against developing fourth-larval stage (L4) and adult <i>A. ceylanicum</i> in cats, a blinded, induced infection study was conducted. Following oral inoculation of 24 purpose bred cats with ˜300 infectious <i>A. ceylanicum</i> larvae each, cats were allocated to one of three groups of eight animals, each which served either as untreated controls or received Broadline® (once topically at the minimum label dose of 0.12 mL per kg bodyweight) when the hookworms were L4 (five days post inoculation, dpi) or adults (25 dpi). Efficacy was determined on nematode counts following necropsy of the cats. Fecal examination at 22 dpi confirmed that all cats of the control group and of the group to be treated when the hookworms were adult were excreting hookworm eggs (range, 100 to 1000 eggs per gram) while no eggs were recovered from the feces of the cats treated with Broadline® 5 dpi. Nematode counts established 35 dpi demonstrated that Broadline® treatment was 100% efficacious against both, developing L4 and adult <i>A. ceylanicum</i>: no hookworms were recovered from any Broadline®-treated cat while all control animals harbored <i>A. ceylanicum</i> (range, 8-35) (<i>p</i> < 0.001). No health problems were observed throughout the study.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"3 ","pages":"100025"},"PeriodicalIF":0.0,"publicationDate":"2020-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7458367/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149018017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shedding and characterization of gastrointestinal nematodes of growing beef heifers in Central Texas.","authors":"D G Riley, J E Sawyer, T M Craig","doi":"10.1016/j.vpoa.2020.100024","DOIUrl":"https://doi.org/10.1016/j.vpoa.2020.100024","url":null,"abstract":"<p><p>Gastrointestinal nematodes (GIN) do not detrimentally affect cattle to the extent of small ruminants. However, they are developing resistance to drugs used to treat them. Genetic strategies to control the nematodes and/or their detrimental effects could be a sustainable alternative to treatment with drugs. An essential first step in development of such a strategy is characterization of nematode populations in commonly used breed types of cattle in local conditions. Fecal egg counts (FEC) were obtained every two months on a cohort of 53 crossbred Nellore-Angus heifers grazing Central Texas pastures from an average heifer age of 3 months to approximately 2 years of age. For 10 of those 12 sets of samples, coprocultures were set up to characterize gastrointestinal nematode species present. Heifers were ½ Nellore ½ Angus (n = 18) or ¾ Angus ¼ Nellore (n = 35). They were born in the spring of 2014 to cows that were from 3-5 years old. They were maintained as a group throughout weaning, postweaning, exposure to bulls as yearlings, and as pregnant cows through the birth of their first calves. An interaction of breed group with sampling time (<i>P</i> < 0.0001) highlighted favorable FEC of ¼ Nellore heifers as compared to ½ Nellore in all but two sampling times. Fecal egg count means were, in general, higher for heifers of both groups in sampling times up to one year of age. Season effects on FEC may be important, but the effect of age may have obscured their detection. There were few significant correlation coefficients for FEC traits with a variety of production traits of these females. Average FEC residuals were positively correlated (r = 0.28 and 0.41; <i>P</i> < 0.05) with winter coat shedding score evaluated at approximately 17 and 24 months of age. Residual correlations of average FEC with calf weaning weight and incidence of shedding with calf age at weaning (r> 0.3) may be indicative of the increased susceptibility of females that lactate heavily or longer to internal parasite infection. Proportions of GIN genera by sampling day differed from <math><msup><mi>χ</mi> <mn>2</mn></msup> </math> expectation (<i>P</i> < 0.0001). <i>Cooperia</i> and <i>Haemonchus</i> species were detected in large proportions in sampling dates that corresponded to heifers less than one year of age. <i>Ostertagia</i> and <i>Trichostrongylus</i> species predominated in sampling dates after heifers reached one year of age.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"3 ","pages":"100024"},"PeriodicalIF":0.0,"publicationDate":"2020-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7458384/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149017525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exposure to ambient air causes degradation and decreased <i>in vitro</i> potency of buparvaquone and parvaquone.","authors":"Siddra A Hines, Jacob Brandvold, Robert H Mealey, Douglas R Call, Telmo Graça","doi":"10.1016/j.vpoa.2020.100023","DOIUrl":"10.1016/j.vpoa.2020.100023","url":null,"abstract":"<p><p>Buparvaquone and parvaquone are hydroxynaphthoquinone compounds commonly used to treat livestock infected with <i>Theileria</i> species such as <i>T. parva</i> and <i>T. annulata</i>. In many (sub)tropical regions, chromatic changes in medicines can result from extreme environmental conditions and improper drug storage or handling, raising the possibility of drug degradation and loss of potency. We evaluated the effects of UV light, elevated temperature, and atmospheric air on the stability and potency of both buparvaquone and parvaquone by using a combination of high performance liquid chromatography (HPLC) and a <i>T. equi</i> based <i>in vitro</i> parasite growth inhibition assay (to measure potency). Aliquots (1 ml; 3 replicates per treatment) of each compound were subjected to a variety of treatments that varied in duration and intensity followed by HPLC and potency assays. Exposure to ambient air for 50 days was correlated with a significant loss of potency for both buparvaquone (4535%, <i>P</i> <  0.05) and parvaquone (247%, <i>P</i> <  0.05), while elevated temperature (37°C) and UV light exposure (24 h) had no significant impact (<i>P</i> >  0.05). The decrease in potency of both buparvaquone and parvaquone correlated with drug degradation (<i>r</i> = -0.74 and -0.88, respectively) as measured by HPLC. In practice, if there is headspace present in the vial, then ambient air will invariably enter the vial and contribute to degradation of these compounds. Such degradation may contribute to increasing drug resistance, economic losses for farmers, and animal welfare concerns for animals that are treated for Theileria infections.</p>","PeriodicalId":23537,"journal":{"name":"Veterinary Parasitology: X","volume":"3 ","pages":"100023"},"PeriodicalIF":0.0,"publicationDate":"2020-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7458381/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147700052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}