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1.
Differences in susceptibility to the myxozoan parasite Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease (PKD), between four strains of rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta) were evaluated. Fish were exposed to water enzootic for the parasite in the field for 5 days and were subsequently transferred to the laboratory. Relative parasite load was determined after 2, 3 and 4 weeks post-exposure (wpe) by quantitative real-time PCR (qPCR) of kidney samples and number of parasite stages was determined in immunohistochemical stained sections of kidney, liver and spleen tissues. According to qPCR results, the highest amount of parasite DNA per equal amount of host tissue at all time points was measured in brown trout. Two of the rainbow trout strains showed lower relative parasite load than all other groups at the beginning of the experiment, but the parasite multiplied faster in these strains resulting in an equal level of relative parasite load for all rainbow trout strains at 4 wpe. A weak negative correlation of fish size and parasite load was detected. Only in samples of a few fish, single stages of T. bryosalmonae were found in sections stained by immunohistochemistry impeding quantitative evaluation of parasite numbers by this method. The results indicate a differential resistance to T. bryosalmonae between the rainbow trout strains investigated and between rainbow trout and brown trout. 相似文献
2.
Christopher M. Good Margaret A. Thorburn Roselynn M. W. Stevenson 《Preventive veterinary medicine》2001,49(3-4)
This paper presents an epidemiological investigation of Ontario Ministry of Natural Resources Fish Health Laboratory data from 1981 to 1997, to determine whether fish species and age were associated with lot-level detection of Aeromonas salmonicida and Yersinia ruckeri in hatchery fish. In stepwise logistic regression, the species brook trout and back-cross (lake trout crossed with the hybrid “splake”) were more likely to test A. salmonicida-positive compared to all other species reared in the hatcheries. Similarly, the species brook trout was significantly more likely to test Y. ruckeri-positive compared to all other species. For both pathogens, the 1–5-month age group was associated significantly with detection. These findings suggest that purposive sampling of higher-risk fish lots could increase the likelihood of detecting both study pathogens. 相似文献
3.
《Journal of aquatic animal health》2013,25(3):109-115
Abstract Laboratory studies were conducted on the susceptibility of different strains of Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss to infection with the monogenean Gyrodactylus salaris. This parasite, probably originating from the Baltic Sea region, is known to minimally affect Neva River (Baltic Sea) Atlantic salmon. However, following its introduction into Norway, G. salaris has caused severe mortality and morbidity among Norwegian Atlantic salmon, which are considered a highly susceptible strain. The cohabitation experiment included one stock of rainbow trout and four different strains of Atlantic salmon from the Baltic Sea region (Mörrum River, Sweden), Europe (Skjern River, Denmark; Conon River, Scotland), and North America (Bristol Cove River, Canada). Fish were exposed to a Norwegian strain of G. salaris, and parasite population development and distribution were monitored for 7 weeks. Rainbow trout exhibited low susceptibility to G. salaris infection, whereas Conon River and Skjern River Atlantic salmon were highly susceptible and exhibited high mortality rates. Mörrum River Atlantic salmon exhibited intermediate susceptibility and low mortality. Bristol Cove River Atlantic salmon harbored relatively low parasite numbers, but fish mortality was high. Our experiment showed that the Danish Skjern River strain of Atlantic salmon is highly susceptible to G. salaris infection, further supporting the hypothesis that Atlantic Ocean strains are more susceptible to G. salaris infection than are Baltic strains. 相似文献
4.
Rubio-Godoy M Paladini G Freeman MA García-Vásquez A Shinn AP 《Veterinary parasitology》2012,186(3-4):289-300
Gyrodactylus salmonis (Yin et Sproston, 1948) isolates collected from feral rainbow trout, Oncorhynchus mykiss (Walbaum) in Veracruz, southeastern Mexico are described. Morphological and molecular variation of these isolates to G. salmonis collected in Canada and the U.S.A. is characterised. Morphologically, the marginal hook sickles of Mexican isolates of G. salmonis closely resemble those of Canadian specimens - their shaft and hook regions align closely with one another; only features of the sickle base and a prominent bridge to the toe permit their separation. The 18S sequence determined from the Mexican specimens was identical to two variable regions of SSU rDNA obtained from a Canadian population of G. salmonis. Internal transcribed spacer (ITS) regions (spanning ITS1, 5.8S and ITS2) of Mexican isolates of G. salmonis are identical to ITS sequences of an American population of G. salmonis and to Gyrodactylus salvelini Kuusela, Zi?tara et Lumme, 2008 from Finland. Analyses of the ribosomal RNA gene of Mexican isolates of G. salmonis show 98-99% similarity to those of Gyrodactylus gobiensis Gl?ser, 1974, Gyrodactylus salaris Malmberg, 1957, and Gyrodactylus rutilensis Gl?ser, 1974. Mexican and American isolates of G. salmonis are 98% identical, as assessed by sequencing the mitochondrial cox1 gene. Oncorhynchus mykiss is one of the most widely-dispersed fish species in the world and has been shown to be an important vector for parasite/disease transmission. Considering that Mexican isolates of G. salmonis were collected well outside the native distribution range of all salmonid fish, we discuss the possibility that the parasites were translocated with their host through the aquacultural trade. In addition, this study includes a morphological review of Gyrodactylus species collected from rainbow trout and from other salmonid fish of the genus Oncorhynchus which occur throughout North America. 相似文献
5.
Luis A. Gmez-Puerta Daniel S. Ticona María T. Lpez-Urbina Armando E. Gonzlez 《Veterinary parasitology》2009,160(3-4):334-336
This report describes the finding of Spirometra erinacei Faust, Campbell & Kellog, 1929 (Cestoda, Diphyllobothridae) infecting the small intestine of two Andean hog-nosed skunks (Conepatus chinga Molina, 1782), collected from the locality “Abra La Raya”, at Cusco, Peru. Four cestodes were studied and identified as S. erinacei. This is the first report showing that the Andean hog-nosed skunk is one of the natural hosts for this parasite. 相似文献
6.
Christopher M. Good Margaret A. Thorburn Carl S. Ribble Roselynn M.W. Stevenson 《Preventive veterinary medicine》2009,91(2-4):254-260
Early-rearing salmonids in Ontario Ministry of Natural Resources (OMNR) fish hatcheries have been consistently affected by bacterial gill disease (BGD) (causative agent: Flavobacterium branchiophilum) for many years. Separate retrospective epidemiological investigations of BGD treatments at two OMNR fish hatcheries (Hatcheries A and B) for the 1999 production year were conducted using on-site hatchery records. Both investigations were carried out at the rearing unit-level, with early-rearing (<9 months of age) “tank-lot” as the unit of analysis to identify unique fish populations over time. Multivariable repeated measures logistic regression models were created for both hatchery datasets, controlling for lot-level and species effects. For Hatchery A, the species brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) were significantly associated with BGD treatment, as well as lower water exchange rate, and higher feeding and mortality percentages during the 2 weeks previous to BGD treatment. At Hatchery B, the species brook trout (S. fontinalis) and splake (Salvelinus namaycush × S. fontinalis) were significantly associated with BGD treatment, as well as lower individual fish weights and treatment for BGD during the previous week. These results emphasize the importance of water quality, feeding rate, fish size and prior mortality on the development of BGD. Significant hatchery and species effects were evident, and future observational research on BGD must account for these factors in their design and analysis. 相似文献
7.
Mamoru Ooshiro Satoshi Zakimi Yoshimasa Matsukawa Makoto Yafuso Yoshito Katagiri Hisashi Inokuma 《Veterinary parasitology》2009,160(3-4):351-355
In October 2007, a 15-year-old Japanese Black cow on Ishigaki Island, Okinawa, Japan, was diagnosed with Anaplasma marginale infection based on clinical symptoms, blood examination, smear observation, 16S rRNA and groEL gene sequence analysis, and the result of a CF test. The cow was introduced into the farm from mainland Japan as a calf in 1993, one year before the eradication of Rhipicephalus (Boophilus) microplus, the main vector of A. marginale in Okinawa Prefecture. It is possible that the cow was first infected with A. marginale as a calf in Ishigaki Island and had been persistently infected since then. This is the first reported clinical case of A. marginale infection of cattle since the eradication of R. microplus in Okinawa Prefecture. Additional analysis of major surface protein 1α amino acid sequences revealed that the A. marginale Okinawa strain presented four new repeat forms which were not seen in other strains. This indicates that the Okinawa strain may be a unique geographical variant of A. marginale. 相似文献
8.
The method of segregating nulliparous and parous females of Culicoides spp. based on the presence of burgundy-red pigment inside the abdominal wall of parous Culicoides midges, is used worldwide. Out of 320 females of Culicoides imicola trapped by emergence traps, set over an artificial breeding site for 10 and 24 days, 73 (22.8%) showed a red-pigmentation despite the fact that they were nulliparous. This finding indicated that 23% of the “parous” females that are examined for the presence of arboviruses and other pathogens or for age-grading purposes, are actually old nulliparous females, which had no chance of acquiring pathogens. This bias in parous rate distorts upward the calculation of vectorial capacity. 相似文献
9.
E. Veronesi G.J. Venter K. Labuschagne P.S. Mellor S. Carpenter 《Veterinary parasitology》2009,163(4):370-373
This laboratory study investigates the sub-adult developmental cycle of field collected Culicoides (Avaritia) imicola Kieffer (Diptera; Ceratopogonidae). The period required from blood-feeding field-collected females to the production of progeny adults occupied 34–56 days at 20 °C, 15–21 days at 25 °C and 11–16 days at 28 °C, demonstrating clear temperature dependence. When reared at 28 °C, C. imicola demonstrated higher variability in fecundity (between 2.4 and 20.6 eggs/female) and lower hatching rates (50.0–62.2%), although larval survival rates to pupation were low at all temperatures (20–30%). Similarly, the mean emergence rate from pupae was the highest at lower temperatures. These results highlight the difficulty in establishing and maintaining a laboratory colony of this species from field-collected material and results are discussed in reference to future research directions that may aid this process. 相似文献
10.
Huseyin Cetin James E. Cilek Levent Aydin Atila Yanikoglu 《Veterinary parasitology》2009,160(3-4):359-361
The acaricidal effects of the volatile essential oil Origanum minutiflorum O. Schwarz & P.H. Davis (Lamiaceae) against adult Rhipicephalus turanicus was evaluated at a variety of concentrations and exposure times. Generally tick mortality increased with concentration and exposure. Ticks exposed to vapors from cotton wicks containing at least 10 μl/L resulted in complete (100%) mortality at 120 min. The major constituent of essential oil obtained from the plant material of O. minutiflorum was carvacrol. 相似文献
11.
P.N.B. De Souza T.C.B. Bomfim F. Huber L.C.S. Abboud R.S. Gomes 《Veterinary parasitology》2009,160(3-4):327-333
To detect Cryptosporidium sp., Giardia sp. and Eimeria leuckarti in horses, fecal samples were collected from three different handling horse groups from the state of Rio de Janeiro, Brazil. Group A was composed of “Mangalarga Marchador” pure breed horses, Group B was formed by horses of a Military Corporation and Group C by stray horses captured by the Center of Zoonosis Control Paulo Dacorso Filho. A total of 396 fecal samples were collected, 212 samples from Group A, 154 samples from Group B and 30 from Group C. The material was submitted to the centrifugation - flotation technique and staining by the safranin-methylene blue technique and analyzed. Oocysts of Cryptosporidium sp. were identified in 0.75% of the samples (n = 3); cysts of Giardia sp. in 0.5% (n = 2) and oocysts of E. leuckarti in 0.5% (n = 2). One case of E. leuckarti in group A and one of Cryptosporidium sp. in group B were observed. In group C were observed two cases of Cryptosporidium, two of Giardia and one of E. leuckarti,. Horses of group C were more parasitized by the three protozoans than animals from the other groups (p < 0.01). It was possible to verify that factors related to the animals, like host individual susceptibility and sanitary factors may influence the occurrence of natural infections by gastrointestinal protozoans, although the age did not have influence. This study reports, for the first time, the occurrence of Cryptosporidium sp., Giardia sp. and E. leuckarti in equines of the State of Rio de Janeiro. 相似文献
12.
Ruiz-Zarzuela I de Bias I Gironés O Ghittino C Múazquiz JL 《Veterinary research communications》2005,29(7):553-562
Coldwater ‘streptococcosis’, caused by Vagococcus salmoninarum, is an emerging disease of rainbow trout in the European Union, causing mortality rates up to 50% in broodstock during the spawning period, with water temperature of 10–12°C. A study to determine the presence and role of this bacterium was undertaken using classical bacteriological techniques confirmed with polymerase chain reaction. This is the first report of isolation of V salmoninarum in relation to outbreaks of mortality in a rainbow trout farm devoted exclusively to broodstock rearing in Spain. A total of 10 isolates of V salmoninarum were characterized by their morphological, cultural, physiological, biochemical and enzymatic traits. Some differences were observed in parameters such as growth on MacConkey agar, H2S production, acid production from starch, and some other minor variations. Isolates were sensitive to erythromycin and oxytetracycline tested in vitro, but treatments conducted in the field were ineffective. An attempt at vaccination did not provide encouraging results. 相似文献
13.
Michele Podaliri Vulpiani Luigi Iannetti Tiberio Di Mattia Paolo Dalla Villa 《Veterinary parasitology》2009,160(3-4):190-197
Leishmaniasis from Leishmania infantum is a parasitary zoonotic disease and a serious problem to public health. Guidelines from Italian Health Authority (Istituto Superiore di Sanità) suggest to control the zoonotic visceral leishmaniasis canine reservoir in endemic areas using an association of preventive and therapeutic tools. Moreover, in literature there are no studies about the long term effects on the disease seroprevalence and incidence in relation to this “holistic” approach. Past research has considered the effects of the alternative employment of preventive or therapeutic treatment, usually for limited periods. In this retrospective study the patterns of seroprevalence and incidence of leishmaniasis in a dog shelter sited in an endemic area of Central Italy are described throughout a 4-year period. Both preventive spot-on tools (imidacloprid/permetrin) and therapeutic protocols based on antimonials and allopurinol were administered. The results showed a progressive reduction of prevalence and incidence of serological reactivity to L. infantum, corroborating the effectiveness of the treatment administered to the animals. Significant improvements from the beginning to the end of the 4-year period were reported, considering both prevalence and incidence. A very low rate of relapses (8% in a pool of 67 subjects positive since 2004; 10.2% among all subjects enrolled in the study) was achieved. 相似文献
14.
Ana Rita Moreira Fernando Paolicchi Claudia Morsella Martin Zumarraga Angel Cataldi Bigi Fabiana Alito Alicia Overduin Piet van Soolingen Dick Romano María Isabel 《Veterinary microbiology》1999,70(3-4)
Sixty-one Mycobacterium avium subsp. paratuberculosis isolates from cattle and deer from the Buenos Aires province, an important livestock region in Argentina, were typed by restriction fragment length polymorphisms (RFLP) analysis based on IS900. Four different RFLP patterns (designated ‘A’, ‘B’, ‘C’ and ‘E’) were identified in BstEII digests of genomic DNA. The most frequently observed type, pattern ‘A’, was found in 46 isolates (75%). The second, pattern ‘E’, included 8 isolates (13%), while the third, pattern ‘B’, included 6 isolates (10%). Pattern ‘C’ was found for only one isolate. All of the deer isolates were classified as pattern ‘A’, while cattle isolates represented all four RFLP patterns. Twenty-one isolates representing the four different BstEII-RFLP patterns were digested with PstI. Twenty isolates showed identical PstI-RFLP pattern. BstEII-RFLP patterns from Argentine cattle and deer were compared with patterns found in cattle, goat, deer, rabbit, and human isolates from Europe. The most common pattern in Argentina, pattern ‘A’, was identical to a less frequently occurring pattern R9 (C17) from Europe. The other Argentine patterns ‘B’, ‘C’ and ‘E’, were not found in the Europe. These results indicate that the distribution of M. avium subsp. paratuberculosis genotypes in the Buenos Aires province of Argentina is different from that found in Europe. 相似文献
15.
Calodium hepaticum (Syn. Capillaria hepatica) is a zoonotic liver nematode of mammals distributed worldwide. Rodents are believed to be the main reservoirs of this nematode. In this paper, prevalence of the parasite was analyzed in liver histological sections from 51 house mice (Mus musculus) caught in human-inhabited houses, from two localities (Furnas and Rabo de Peixe) on São Miguel island from the Azores archipelago (Portugal). Mean prevalence of infection was 19.6%, with 33.3% prevalence in Furnas and 4.1% in Rabo de Peixe (P = 0.07). No significant differences were found between the prevalence of infection and the age, body weight and the sex of mice. Hepatic lesions found were either acute and/or chronic stage and consisted of moderate to severe multifocal pyogranulomatous hepatitis with encapsulated eggs with typical bipolar plugs and moderate to severe necrotizing hepatitis consistent with larva tracks. Periportal inflammatory infiltration, hepatocyte regeneration and bile duct hyperplasia were also noted. In most cases, hepatic lesions occupied more than 50% of the liver, but despite severe lesions, in some mice, no signs of hepatic failure were noticed. The high rate of infection found in the present study suggests that house mice are an important reservoir for this parasite in the Azores and could have a role in human transmission. 相似文献
16.
C. Lupini M. Cecchinato A. Scagliarini R. Graziani E. Catelli 《Research in veterinary science》2009,87(3):482-487
Field evidences have suggested that a natural extract, containing tannins, could be effective against poultry enteric viral infections. Moreover previous studies have shown that vegetable tannins can have antiviral activity against human viruses. Based on this knowledge three different Chestnut (Castanea spp.) wood extracts and one Quebracho (Schinopsis spp.) wood extract, all containing tannins and currently used in the animal feed industry, were tested for in vitro antiviral activity against avian reovirus (ARV) and avian metapneumovirus (AMPV). The MTT assay was used to evaluate the 50% cytotoxic compounds concentration (CC50) on Vero cells. The antiviral properties were tested before and after the adsorption of the viruses to Vero cells. Antiviral activities were expressed as IC50 (concentration required to inhibit 50% of viral cytopathic effect). CC50s of tested compounds were >200 μg/ml. All compounds had an extracellular antiviral effect against both ARV and AMPV with IC50 values ranging from 25 to 66 μg/ml. Quebracho extract had also evident intracellular anti-ARV activity (IC50 24 μg/ml). These preliminary results suggest that the examined vegetable extracts might be good candidates in the control of some avian virus infections. Nevertheless further in vivo experiments are required to confirm these findings. 相似文献
17.
18.
Danny Morick Gad Baneth Boaz Avidor Michael Y. Kosoy Kosta Y. Mumcuoglu Dvir Mintz Osnat Eyal Ralph Goethe Andreas Mietze Nahum Shpigel Shimon Harrus 《Veterinary microbiology》2009,139(3-4):293-297
The prevalence of Bartonella spp. in wild rodents was studied in 19 geographical locations in Israel. One hundred and twelve rodents belonging to five species (Mus musculus, Rattus rattus, Microtus socialis, Acomys cahirinus and Apodemus sylvaticus) were included in the survey. In addition, 156 ectoparasites were collected from the rodents. Spleen sample from each rodent and the ectoparasites were examined for the presence of Bartonella DNA using high resolution melt (HRM) real-time PCR. The method was designed for the simultaneous detection and differentiation of eight Bartonella spp. according to the nucleotide variation in each of two gene fragments (rpoB and gltA) and the 16S–23S intergenic spacer (ITS) locus, using the same PCR protocol which allowed the simultaneous amplification of the three different loci. Bartonella DNA was detected in spleen samples of 19 out of 79 (24%) black rats (R. rattus) and in 1 of 4 (25%) Cairo spiny mice (A. cahirinus). In addition, 15 of 34 (44%) flea pools harbored Bartonella DNA. Only rat flea (Xenopsyla cheopis) pools collected from black rats (R. rattus) were positive for Bartonella DNA. The Bartonella sp. detected in spleen samples from black rats (R. rattus) was closely related to both B. tribocorum and B. elizabethae. The species detected in the Cairo spiny mouse (A. cahirinus) spleen sample was closely related to the zoonotic pathogen, B. elizabethae. These results indicate that Bartonella species are highly prevalent in suburban rodent populations and their ectoparasites in Israel. Further investigation of the prevalence and zoonotic potential of the Bartonella species detected in the black rats and the Cairo spiny mouse is warranted. 相似文献
19.
Inmaculada A. Herrero Tirushet Teshager Julian Garde Miguel A. Moreno Lucas Domínguez 《Preventive veterinary medicine》2000,47(4)
A study to estimate the prevalence of vancomycin-resistant Enterococcus faecium in faecal samples from pigs at slaughterhouses in Spain was carried out between November 1998 and January 1999 with 900 samples taken from four abattoirs representing 9.7% of all pig slaughtered in 1998. Using a selective enrichment broth with vancomycin (8 μg/ml), 64 samples (7.1%; 95% CI: 5.5, 9.0%) had E. faecium vancomycin-resistant strains that showed minimal inhibitory concentrations of 256 μg/ml (62 strains) and 512 μg/ml (two strains). Results by farm showed that 43 of the 240 pig farms represented in the sampling had at least one faecal sample with vancomycin-resistant E. faecium. 相似文献
20.
Beata Mal
ekov Monika Halnov Zlatana Sulínov Ladislav Molnr Petra Ravaszov Jozef Adam Milo&#x; Haln Igor Valocký Milan Baranovi
《Research in veterinary science》2010,89(3):358-361
The presence of antibodies against Encephalitozoon cuniculi (E. cuniculi) and Encephalitozoon intestinalis (E. intestinalis) was examined in 215 samples from humans and in 488 samples from five different species of domestic and companion animals in Slovakia. The 215 human samples and samples from 90 swine, 123 non-infected cattle (cattle), 24 cattle infected with bovine leukosis virus (BLV-positive cattle), 140 sheep and 111 dogs were examined by the enzyme-linked immunosorbent assay (ELISA). Samples with serum titres 1:200 or higher were considered as positive. Specific anti-E. cuniculi antibodies were found in humans (0.9%), swine (52%), cattle (2%), sheep (9%) and dogs (15%) except for the BLV-positive cattle at the titre of 1:200. The titre of 1:400 was detected only in humans (0.5%). The presence of specific anti-E. intestinalis antibodies at the titre of 1:200 was confirmed in humans (6%), swine (51%), cattle (11%), BLV-positive cattle (13%) and dogs (6%) but not in sheep. The anti-E. intestinalis antibodies reached the 1:400 in humans (1%), swine (4%) and BLV-positive cattle (17%). The presence of specific anti-E. intestinalis antibodies at the titre of 1:600 was observed only in one swine (1%). Significant differences were observed in animals at titres 1:200 and 1:400 (chi-squared test: p < 0.0001) for both pathogens and in humans only for E. cuniculi at the titre of 1:400 (chi-squared test: p < 0.0075). 相似文献