首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
The discovery of the parasite Toxocara vitulorum in bison calves in the province of Manitoba, Canada is discussed. This parasite is more commonly found in the small intestines of bovid calves living in tropical and subtropical regions of the world. This is the first time that Toxocara vitulorum has been reported from hosts in Canada.  相似文献   

2.
This study was completed to determine the prevalence and distribution of Toxocara vitulorum infection in cattle and buffalo calves and investigate its clinical impact in northern Lao PDR (Peoples Democratic Republic). The results aim to assist decisions on disease control measures that can contribute to increasing cattle and buffalo productivity within smallholder farming systems in tropical areas. A prevalence survey for T. vitulorum in buffalo and cattle calves aged <3 months was conducted between September 2009 and June 2010 in five provinces of northern Lao PDR using a two-stage sampling technique to select 69 villages and 899 calves, with faecal samples collected and examined for T. vitulorum eggs at a local laboratory. At the time of sampling, data on calf morbidity and anthelmintic treatment was also collected. Factors potentially associated with infection and severity of infection were analyzed at univariable and multivariable levels, using T. vitulorum status (positive/negative) and on the positive calves only, faecal egg count levels as outcome variables. The estimated prevalence of T. vitulorum in northern Lao was 22.6 % (95 % confidence interval [CI], 0.17–0.28), and 76.8 % of villages had at least one positive calf. Province was the only significant (p?<?0.05) variable investigated associated with calf infection status. Species (buffalo) was the only variable significantly (p?<?0.05) associated with higher egg per gram of faeces levels among infected calves. Prevalence in calves aged 1–21 days, the reported prepatent period, was 17.5 % (CI 0.11–0.24). Treatment levels were very low (8.2 %) and if treatment occurred it was mostly unsuccessful. The high and wide spread infection of T. vitulorum in cattle and buffalo calves identified in this survey is likely to result in suboptimal cattle and buffalo productivity. Improved management of T. vitulorum infection in cattle and buffalo calves in northern Lao PDR is indicated to reduce potential negative production impacts and enable more efficient development of large ruminant livestock industry as a pathway from rural poverty for smallholder farmers in northern Lao PDR. In addition to quantifying this disease problem in calves, the conduct of this applied participatory research study provided an important opportunity to improve animal health services by increasing the parasite, large ruminant handling and research knowledge and capacity of government animal health staff and farmers.  相似文献   

3.
The objective of this study was to determine prevalence, intensity, and zoonotic potential of gastrointestinal parasites in free-roaming and pet cats in urban areas of Saskatchewan (SK) and a rural region in southwestern Alberta (AB). Fecal samples were analyzed using a modified double centrifugation sucrose flotation to detect helminth eggs and coccidian oocysts, and an immunofluorescence assay to detect Giardia and Cryptosporidium. Endoparasite prevalence was higher in samples from rural AB cats (41% of 27) and free-roaming SK cats (32% of 161) than client-owned SK cats (6% of 31). Parasites identified using morphological and molecular techniques included Toxocara cati, Toxascaris leonina, Baylisascaris-type eggs, Eucoleus aerophilus, Taenia taeniaeformis, Isospora spp., Cryptosporidium spp., and zoonotic genotype A of Giardia duodenalis. This study demonstrates significant differences in endoparasite prevalence in feline populations, and the value of molecular techniques in fecal-based surveys to identify and determine parasite zoonotic potential.  相似文献   

4.
Buffalo aged 3–15 months on institutional farms and in the villages of an irrigation project were monitored for gastrointestinal nematodes by faecal egg counts over two years. Apart from treatment for Toxocara vitulorum at 10–16 days of age, no anthelmintics were used. Half of the strongylid egg counts were zero and 90% were less than 500 epg of faeces on the institutional farms, and 67% were zero and 97% less than 500 epg in the villages. No problems arose during four years without anthelmintics on the institutional farms and during two years in the villages. Autopsies demonstrated that the eggs which were present were produced by mixed infections of small numbers of Haemonchus spp., Mecistocirrus digitatus, Trichostrongylus spp., Bunostomum phlebotomum and Cooperia spp. High egg counts of Strongyloides papillosus occurred in calves up to six months old, but were not pathogenic.  相似文献   

5.
Toxocara (Neoascaris) vitulorum is a gastrointestinal nematode parasite of young ruminants, responsible for high mortality rates in parasitized cattle and buffalo calves. The objective of this work was to compare the predatory capacity under laboratory conditions of four fungal isolates of the nematophagous fungus Pochonia chlamydosporia (VC1, VC4, VC5 and VC12) on T. vitulorum eggs in 2% water-agar (2% WA). T. vitulorum eggs were plated on 2% WA Petri dishes which contained cultured fungal isolates and control plates without fungi. After 10 and 15 days one hundred eggs were removed and classified according to the following parameters: type 1, biochemical and physiological effect without morphological damage to the eggshell, type 2, lytic effect with morphological alteration of the eggshell and embryo and type 3, lytic effect with morphological alteration of eggshell and embryo in addition to hyphal penetration and internal egg colonization. The fungal isolates were effective in the destruction of T. vitulorum eggs presenting the type 3 effect at 10 and 15 days after contact with the fungus. No nematophagous fungi were observed in the control group during the experiment. There was no variation in the predatory capacity of the fungal isolates (P?>?0.01) at the intervals of 10 and 15 days. These results indicate that P. chlamydosporia (VC1, VC4, VC5 and VC12) negatively influenced the development of T. vitulorum eggs and can be considered a potential candidate for the biological control of nematodes.  相似文献   

6.
A fecal survey was conducted to determine the prevalence of gastrointestinal helminth eggs found in 431 domestic bison from 22 herds. Eggs detected (percent of herds affected in parentheses) were: strongyle-type (100%), Capillaria sp. (63.6%), Moniezia sp. (54.6%), Nematodirus sp. (50%), Trichuris sp. (40.9%), and Strongyloides sp. (9.1%).  相似文献   

7.
This study was made to investigate efficacy of eprinomectin pour-on against to Toxocara vitulorum in calves. In the study, 16 calves naturally infected with T. vitulorum were divided into two groups as treatment (eight calves) and control (eight calves). Eprinomectin (0.5 mg/kg, Eprinex®, Merial) was given to treatment group calves, and eggs per gramme were determined in the faeces on the day of pre-treatment and the second, third, fourth, fifth, sixth, 14th and 28th days of post-treatment. No side effects associated with nervous, respiratory and gastrointestinal systems were observed. In conclusion, eprinomectin was determined to be 100% effective against T. vitulorum. This is the first study to evaluate the efficacy of eprinomectin against a natural T. vitulorum infection in calves.  相似文献   

8.
Toxocara vitulorum infection in large ruminants is endemic in many tropical countries and particularly in South-East Asia. A single treatment of calves with pyrantel at 14–21 days of age effectively controls the parasite. Despite this treatment being readily available, T. vitulorum infection remains common and widespread. To understand drivers of effective control of T. vitulorum infection, we examined treatment practices and knowledge of smallholder farmers of this parasite plus determined annual calf morbidity and mortality and identified potential risk factors for these estimates. Interviews were conducted with 273 smallholder farmers who had calves tested for T. vitulorum 4–6 months earlier. Reproductive rates of 0.6 and 0.4 calf per annum in cattle and buffalo respectively, and annual calf morbidity and mortality of 42.6% (CI 0.38–0.47) and 37.3% (CI 0.33–0.42) respectively, were identified. Interviewed farmers had either none (80.6%) or only minimal (19.4%) knowledge about T. vitulorum and only 2.5% of the farmers treated their calves for T. vitulorum using the recommended control regime. Multivariable logistic regression analyses with random effects showed that the number of adult cattle per household, T. vitulorum infection status of the household herd and farmer knowledge of T. vitulorum were significantly associated with calf morbidity and mortality. Financial analysis using partial budgeting showed a net benefit of USD 3.69, 7.46, 11.09 or 14.86 per calf when treating calves with pyrantel and attributing 25%, 50%, 75% or 100% of morbidity and mortality to T. vitulorum infection. The study identified that poor reproduction, high calf morbidity and mortality combined with very limited farmer knowledge and effective control of endemic Toxocariasis, contribute to suboptimal large ruminant production in mixed smallholder farming systems in South-East Asia. The large net benefit per calf achievable by a single pyrantel treatment should drive implementation of this intervention by smallholder farmers, especially as demand for livestock products continues to increase in this region and forces a change to more production oriented farming. To support this, continued capacity building that ensures knowledge transfer of best practice T. vitulorum control to smallholder farmers is required.  相似文献   

9.
Serum samples were collected at slaughter from 226 24-30-month-old ranch-raised, clinically normal American bison (Bison bison) bulls from North Dakota, Minnesota, Kansas, and Manitoba to assess the presence of antibodies to ovine herpesvirus 2 (OHV-2). Antibodies to OHV-2 were detected by competitive inhibition enzyme-linked immunosorbent assay in 10 of 226 (4.40%) samples. Polymerase chain reaction (PCR) analysis of sera positive for OHV-2 DNA demonstrated a 238 kilobase fragment. The nucleotide sequence of the PCR-positive samples in comparison to the reported OHV-2 nucleotide sequence resulted in a homology range of 82.8-95.4%.  相似文献   

10.
In two small farms in Sweden young calves were found to be naturally infected with Ascaris suum. One of the calves expelled mature worms with the faeces, one had a great number of worms in the ductus choledochus and two others had worms in the intestine. Most of the worms were mature and at the egg-producing stage. The morphology of the eggs and the adult worms indicated that these parasites were A. suum and that Toxocara (syn. Neoascaris) vitulorum could be excluded.  相似文献   

11.

A cross-sectional study was carried out to determine the prevalence and distribution of Fasciola gigantica infections in communally grazed and ranch-grazed beef cattle through coprological examination. A total of 8646 cattle (4618 adults, 2843 weaners and 1185 calves) faecal samples were collected during the 24 months of study. Results from this study indicated that only 64 (0.74%; 95% CI 0.57, 0.94%) of the samples were positive for F. gigantica eggs. The positive samples were detected in one (Central) of the six study districts and was restricted to the Tuli Block (commercial) farms in Machaneng village in eastern Botswana. The prevalence of fluke eggs was significantly higher in adult cattle (12.85%; 95% CI 9.72, 16.54%) than weaners (6.49%; 95% CI 3.40, 11.06%) and calves (0.79%; 95% CI 0.02, 4.31%), (χ2(2)?=?19.01, p?<?0.001). Thus, adults (OR?=?18.57; 95% CI 2.54, 135.81%) were approximately 20 times more likely to be infected than calves. By taking liver inspection as a gold standard for diagnosis of fasciolosis, the sensitivity of the sedimentation technique was found to be 72.41% and the specificity 100%, with moderate relationship (κ?=?0.53; 95% CI 0.31–0.75) between the two methods. This study has demonstrated that infection of cattle from Botswana, with F. gigantica, was low and distribution of the fluke appeared to be linked to suitable environmental conditions for the intermediate host snail. However, detailed surveillance studies, involving more cattle and areas, are required to verify the true prevalence. Such information would assist in the design of appropriate, strategic and effective fluke control programmes.

  相似文献   

12.
A national bovine serological survey was conducted to confirm that the prevalence of brucellosis, bluetongue, and anaplasmosis does not exceed 0.02% (95% confidence) in live cattle in Canada. Sampling consisted of a systematic random sample of 15 482 adult cattle slaughtered in federally inspected abattoirs, stratified by province. Samples were tested to detect antibodies for brucellosis, bluetongue, and anaplasmosis. All samples were negative for brucellosis. Three samples were seroreactors to bluetongue, 2 of which originated from the Okanagan Valley in British Columbia and 1 from Ontario, which after follow-up, was considered an atypical result. A total of 244 samples were seroreactors to Anaplasma and follow-up identified infection in Saskatchewan, Manitoba, and Quebec. In conclusion, the Canadian cattle population remains free of brucellosis and free of bluetongue outside the Okanagan Valley. Canada is no longer free of anaplasmosis and will be unable to claim freedom until eradication measures are completed.  相似文献   

13.
Examinations of complete or partial remains of 72 bison found dead in and around Wood Buffalo National Park, Canada, revealed evidence of brucellosis in 18 (25%) and tuberculosis in 15 (21%), with a combined prevalence of 42%. Urease-positive and ureasenegative strains of Brucella abortus biovar 1, and strains of biovar 2, were isolated from tissues of bison, including synovium and exudate from severe arthritic lesions. Mycobacterium bovis was isolated from a range of granulomatous lesions that were similar to those reported in tuberculous cattle. Diseased bison had a broad geographical distribution, and were found outside the park on at least three natural corridors. The diseases have a deleterious effect on this population of bison, and pose a health risk to other bison herds, livestock, and native hunters in the region.  相似文献   

14.
Serum samples were collected at slaughter from 226 24-30-month-old American bison (Bison bison) bulls from Kansas, Minnesota, North Dakota, and Manitoba and assayed for antibodies to ovine herpesvirus type-2 (OHV-2), bovine viral diarrhea virus (BVDV), bovine herpesvirus type-1 (BHV-1), and bovine respiratory syncytial virus (BRSV). Antibodies were detected by serum neutralization for BVDV, BHV-1, and BRSV, while antibodies to OHV-2 were detected by competitive inhibition-ELISA (CI-ELISA). Detectable antibodies were found against all viruses: 10 of 226 (4.40%) against OHV-2, 125 of 226 (55.3%) against BVDV, 99 of 226 (43.8%) against BHV-1, and 208 of 226 (92.0%) against BRSV. Titers from 93.6% of the BVDV-positive animals, 79.8% of the BHV-1-positive animals, and 98.1% of the BRSV-positive animals were > or = 1.25. These data indicate that a low percentage of clinically normal bison are seropositive for OHV-2 while a high percentage of bison sampled are seropositive for BVDV, BHV-1, and BRSV.  相似文献   

15.
The 247 calves from 112 Creole cows of Guadeloupe were monitored for Toxocara vitulorum infection from year 2002 to 2005. The cows were in good body condition and the calf growth rate was 880g/d on average. The overall prevalence of infection was estimated to 0.77 [0.72; 0.83]. The faecal egg count peaked 49 days after calf birth, and then decreased. No clinical symptom related to T. vitulorum infection was observed, and no effect on the calf growth rate was shown. It was concluded that, despite the high prevalence of T. vitulorum, the production loss remains under the level of detection, and no drenching is needed for well-fed animals.  相似文献   

16.
Seroprevalence and associated risk factors for Toxoplasma gondii infection in pigs were analyzed in 1202 sera samples, including sows and pigs of three, seven, 11, 15 and 20 weeks of age, from 23 farms in Catalonia, north-eastern Spain. Antibodies were tested by the modified agglutination test (MAT) at titers ?1:25. Antibodies to T. gondii were found in 228 samples (19.0%; 95% CI: 16.8-21.2). The individual prevalence in animals higher than 7 weeks of age was 22.8% (174/762; 95% CI: 16.6-29.0) and the within-farm prevalence ranged from 7.1% to 36.4%. Statistically significant differences were found among age classes. The risk factors significantly associated with T. gondii seroprevalence were the presence of cats, percentage of mortality at weaning and the presence of outdoor facilities in the farms. The seroprevalence observed in the present study indicates widespread exposure to T. gondii among domestic pigs in Catalonia, which may have important implications for public health.  相似文献   

17.
Cystic echinococcosis is a major emerging zoonosis in many Eastern European and Asian countries. Post slaughter examinations of 684 pig livers in Lithuania revealed significantly higher numbers of Echinococcus granulosus infections in animals from family farms (13.2%; 95% CI 10.7–16.2) as compared with those from industrial farms (4.1%; 95% CI 0.8–11.5). The prevalence was also significantly higher in pigs older than 1 year than in younger ones. In addition, in 0.5% of the pigs from the family farms, infertile and calcified E. multilocularis lesions were identified by PCR. Faecal samples from rural dogs (n = 240) originating from 177 family farms in 12 villages were investigated for taeniid eggs with two methods. Significantly more dogs excreting taeniid eggs were diagnosed with the flotation/sieving method (n = 34) as compared to the modified McMaster method (n = 12). Multiplex PCR performed with DNA from taeniid eggs isolated from faeces of 34 dogs revealed 26 infections with Taenia spp., 9 with E. granulosus and 2 with E. multilocularis (4 cases with concurrent Taenia spp. and E. granulosus or E. multilocularis infections). Genotyping of E. granulosus cyst tissues from 7 pigs, 1 head of cattle and from E. granulosus eggs from 8 dog faeces revealed the genotype G6/7 (‘pig/camel strain’) in all cases. The high infection pressure with Echinococcus spp. in family farms necessitates initiating control programs.  相似文献   

18.
Mycoplasma suis, the causative agent of porcine infectious anemia, causes large economic losses to the swine industry worldwide. A questionnaire-based survey was conducted in 69 pig farms in Hubei Province, China, from November 2011 to August 2013 to ascertain the prevalence and associated risk factors of M. suis. Four thousand and four blood samples from pigs of all the age groups were tested for M. suis antibodies using the established rMSG1–ELISA assay. Among these 4004 samples, 1615 blood samples from multiparous sows were examined to identify the association between seroprevalence and different seasons. Information on risk factors collected from farmers or attending veterinarians was recorded on a pre-designed questionnaire. The overall test seroprevalence of M. suis infection at the animal level was 31.9% (1277/4004; 95% CI: 30.5%, 33.4%), whereas at the farm level, this value was 95.65% (66/69; 95% CI: 87.8%, 99.1%). The seroprevalence of M. suis was higher in replacement gilts (40.6%; 95% CI: 35.1%, 46.3%), multiparous sows (48.2%; 95% CI: 45.8%, 50.7%) and boars (44.4%; 95% CI: 34.5%, 54.8%), as compared to piglets (13.0%; 95% CI: 9.4%, 17.3%), weaned-piglets (10.8%; 95% CI: 8.9%, 13.0%), and growing-finishing pigs (25.0%; 95% CI: 22.0%, 28.3%). In terms of seasons, the prevalence of M. suis in pigs was significantly higher in summer (65.3%; 95% CI: 61.0%, 69.5%) and autumn (65.0%; 95% CI: 59.0%, 70.6%) compared to spring (30.1%; 95% CI: 26.0%, 34.4%) and winter (36.4%; 95% CI: 31.4%, 41.5%). Farm-level risk factors were identified by multivariable logistic regression analysis. The associated factors retained in the final multivariable logistic regression model were drug treatment, presence of mosquitoes and flies, and frequency of disinfection. Drug treatment (OR = 0.24; 95% CI: 0.07, 0.88; P = 0.031) and frequency of disinfection (OR = 0.23; 95% CI: 0.06, 0.90; P = 0.035) were protective factors, and the presence of mosquitoes and flies (OR = 5.994; 95% CI: 1.56, 23.00; P = 0.009) was a risk factor for M. suis infection on farms. The results of the present study provide the first insight into the impact of associated determinants on M. suis infection in central China.  相似文献   

19.
The extraparasitic life cycle of Toxocara vitulorum of buffalo in the villages of Sri Lanka is related to observations on buffalo behaviour, experimental studies on the development and persistence of the eggs in soil and in wallows and the presence of eggs in village locations. Calf faeces on soil were rapidly incorporated by insect activity and the eggs developed only slightly slower than in the laboratory. Some infective eggs persisted 3–4 cm deep for 17 months, finally dying during a prolonged hot, dry period. Eggs in a wallow developed intermittently over 16 months as it was flushed with rain water, and eventually died when the wallow dried out. When infected faeces were placed in water, decomposition caused some material to rise to the surface and eggs developed. In villages, eggs are ubiquitous where young calves are kept but survive best where there is moisture and shade around animal pens and wallows. Cows and calves acquire infection from infective eggs in wallow water, soil and pasture, while calves may also be infected from contamination on the udder and teats of the cow. The larvae resulting from this infection do not mature until the infection is passed to the calf through the milk of the cow. At least 72% of village calves have patent infections and current treatment procedures do not reduce the prevalence.The possibility that T. vitulorum is a cause of human visceral larva migrans is discussed.  相似文献   

20.
Leptospirosis and toxoplasmosis are zoonoses with high importance because of the economic and public health impact. This study was aimed to determine the seroprevalence of leptospirosis and toxoplamosis in 714 serum samples of horses from different farms from Botucatu, São Paulo, Brazil. The samples were researched for Toxoplasma gondii antibodies by indirect immunofluorescence antibody test (IFAT) and for Leptospira spp. antibodies by microscopic agglutination test. Of 714 serum samples, 128 (17.9%; 95% CI: 15.3%-20.9%) were positive for one or more serovars of Leptospira spp., with icterohaemorrhagiae, canicola, and castellonis as the most prevalent serovars, whereas 42 (5.9%; 95% CI: 4.4%-7.9%) were positive for T gondii, of which 33 samples (78.57%; 95% CI: 64.0%-88.2%) presented a titer of 16, 7 (16.7%; 95% CI: 8.4%-30.7%) a titer of 64, and 1 (2.38%; 95% CI: 0.6%-12.3%) a titer of 256. No significant difference was found among the results obtained and the associated variables such as age and sex.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号