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1.
The prevalence and infection pattern of naturally acquired giardiasis and cryptosporidiosis in 20 ranch raised beef calves and their dams from birth to weaning was determined. Rectal fecal samples were collected from calves at 3 days of age and weekly thereafter; cows' fecal samples were collected at the time of calving, 1 week later and four times during the summer grazing period. Blood samples were collected from the calves at 3 days of age to determine IgG(1) concentrations. Giardia lamblia cysts were shed by all 20 calves (100%) at some date during the duration of the study. However, only one calf (5%) shed Cryptosporidium parvum on two sample dates during the trial. Giardia cysts were first detected at 3.9+/-1.37 weeks of age with a range of 2-7 weeks of age. The geometric mean number of Giardia cysts in the calf feces increased from none at 1 week of age to a maximum of 2230 cysts/g of feces at 5 weeks of age and then decreased to 2 cysts/g at 25-27 weeks of age. Infection rate of calves shedding Giardia cysts peaked at 85% at 5 weeks of age and then decreased to 21% at 25-27 weeks of age. Giardia cysts, shed by calves peaked 1 week after initial shedding and decreased (P<0.05) for the remainder of the trial with the exception of week 3. There was a lower (P<0.05) percentage of calves shedding Giardia cysts weeks 3-10 and 15-25 compared to when shedding was first detected. All calves had complete or partial transfer of passive immunity as measured by IgG(1) levels. The rate of infection (15%) and the geometric mean number of Giardia cysts in the cows' feces (38.49 cysts/g) numerically increased at 1 week post-calving compared to levels at calving. The rate of infection (40%) numerically increased and the geometric mean number of Cryptosporidium andersoni oocysts in the cow feces (37.48 oocysts/g) increased (P<0.05) at 1 week post-calving and decreased to 0 at 13-16 weeks post-calving. This study is the first to document the cumulative prevalence and infection patterns of Giardia and Cryptosporidium in beef cattle under ranch conditions.  相似文献   

2.
The assemblage of 37 Giardia intestinalis samples was determined, 19 obtained from puppy feces, 12 from stools of different human subjects under 3 years of age and 6 from axenic culture. The assemblages were classified according to the restriction pattern of beta-giardin gene with Hae III enzyme. Results showed that dog assemblages were grouped AI (52.6%) and AII (47.4%), while 41.7% human samples belonged to genotype AI and 58.3% to genotype AII. All axenic cultures belonged to assemblage AI; types AI and AII were both found in dog and human feces by Hae III restriction enzyme assay, suggesting a similarity between human and dog parasites. These results suggest that domestic animals infected with Giardia could produce cysts potentially infective for humans.  相似文献   

3.
Prevalence of Giardia in the feces of pups   总被引:1,自引:0,他引:1  
Fecal specimens were collected from 117 healthy pups (79 privately owned pups and 38 pups from an animal shelter) and analyzed for Giardia. Giardia cysts or trophozoites were found in 35.9% of the dog feces.  相似文献   

4.
The efficacy of a Giardia lamblia vaccine in kittens.   总被引:1,自引:0,他引:1       下载免费PDF全文
Twenty kittens were vaccinated with a Giardia lamblia vaccine prepared on a commercial scale on day 0 and boosted on day 21 (group 1); while 10 kittens received only saline (group 2). These kittens were challenged on day 35 with 10(6) Giardia lamblia trophozoites by a surgical intraduodenal injection. Three control kittens were not vaccinated and not challenged (group 3). Following challenge, Giardia vaccinated kittens had significantly fewer days in which abnormal stools were observed and reduced food intake occurred compared to saline injected animals. The rate of weight gain between group 1 and group 2 animals was not different in the prechallenge period (day 0 to day 35), but vaccinated animals had a significantly higher weight gain in the postchallenge period (P < 0.05). On day 56, all vaccinated animals were not passing cysts in their feces, while 40% of saline injected kittens had Giardia cysts in their feces. In vaccinated kittens, cysts were never demonstrated in 45% of the animals, while cysts were detected in 90% of the saline injected kittens. Viability of the cysts in vaccinated kittens was 38% while the cysts viability in saline injected kittens was 99%. On postmortem examination, trophozoites could be detected in 5% of vaccinated kittens and 60% of saline injected kittens. Vaccination produced an elevated Giardia specific serum IgG and IgA response prior to challenge and throughout the postinfection period. The Giardia infection in the saline injected group did not induce an elevated specific serum response. Giardia vaccination of kittens provides protection in kittens from an experimental challenge by reducing or eliminating intestinal trophozoites and fecal cyst excretion.  相似文献   

5.
A study was undertaken to determine the prevalence of Giardia infections in dairy calves and to compare Giardia and Cryptosporidium infections in calves of different ages. Fresh fecal samples were collected from 386 male and female Holstein calves (newborn to 24 wk) in 20 dairies located in the lower Fraser river valley area of British Columbia. Giardia intestinalis, Cryptosporidium parvum, and Cryptosporidium muris were enumerated in each sample after concentration by sucrose gradient centrifugation and immunofluorescent staining. Giardia was identified at all farm locations. The overall prevalence of Giardia in calves was 73% with a geometric mean cyst count of 1180 cysts per gram of feces (CI, 41 to 5014). Cryptosporidium parvum and C. muris were identified in 80% and 40% of the farms, respectively. The prevalence of C. parvum was 59%, and the geometric mean for oocysts was 457 oocysts per gram of feces (CI, 18 to 160). The prevalence of C. muris was only 2% and the mean oocyst counts were 54 oocysts per gram of feces. Giardiasis was not age dependent, and approximately 80% of the calves from 2 to 24 wk were infected. In contrast, C. parvum infections were predominant in calves 2 to 4 wk, while C. muris was demonstrated in calves older than 4 wk. Fourty-seven percent of calves with diarrhea had high numbers of Giardia cysts in their feces. Giardia infections are highly prevalent in dairy calves and should be considered in animals with diarrhea or failure to thrive.  相似文献   

6.
OBJECTIVE: To determine the total number of Cryptosporidium parvum oocysts and Giardia spp cysts shed by dairy calves during the period when they are most at risk after natural infection. ANIMALS: 478 calves naturally infected with C. parvum and 1,016 calves naturally infected with Giardia spp. PROCEDURE: Oocysts or cysts were enumerated from fecal specimens. Distribution of number of oocysts or cysts versus age was used to determine the best fitting mathematic function. Number of oocysts or cysts per gram of feces for a given duration of shedding was computed by determining the area under the curve. Total number of oocysts or cysts was calculated by taking the product of the resultant and the expected mass of feces. Results: Intensity of Cparvum oocyst shedding was best described by a second-order polynomial function. Shedding increased from 4 days of age, peaked at day 12, and then decreased. An infected 6-day-old calf would produce 3.89 x 10(10) oocysts until 12 days old. Pattern of shedding of Giardia spp cysts was best described by exponential functions. Intensity of shedding increased from 4 days of age, peaked at day 14, and then decreased. An infected calf would produce 3.8 x 10(7) cysts from day 50 until day 56. CONCLUSIONS AND CLINICAL RELEVANCE: The large number of oocysts and cysts shed indicates that shedding by dairy cattle poses a risk for susceptible calves and people. Estimates reported here may be useful to aid in designing cost-effective strategies to manage this risk.  相似文献   

7.
Infections with the intestinal protozoan parasite Giardia in dogs and cats are common. Clinical signs vary from asymptomatic to small bowel diarrhea and associated discomfort. The control of infections in dogs is frequently a frustrating issue for animal owners and veterinarians. Drugs with antiprotozoal activity such as fenbendazole and metronidazole are recommended, however, they do not show 100% efficacy and superinfections occur regularly. Ronidazole is currently the drug of choice for the treatment of Tritrichomonas foetus in cats and there is now limited information available about its efficacy against Giardia spp. In the kennel investigated, dogs regularly showed loose feces and the presence of Giardia (assemblage C, renamed as G. canis) cysts. An elimination strategy of this parasite involving strict hygiene management and disinfection of the enclosures with 4-chlorine-M-cresol, oral treatment with ronidazole (30-50mg/kg BW bid for 7 days) and two shampooings (containing chlorhexidine) at the beginning and the end of the treatments was implemented for a group of 6 dogs. As a control another group of 7 dogs was transferred to the disinfected enclosures and shampooed, but left untreated. Dog feces were tested for the presence of Giardia cysts (SAF concentration technique) or Giardia antigen with a commercial ELISA (NOVITEC(?)) and a quick immunochromatography-based test (SensPERT(?)) before and between 5 and 40 days after the last treatment. All ronidazole-treated dogs were negative for Giardia cysts and antigen up to 26 days after the last treatment, while between 1 and 5 of the control animals tested positive in each of the test series. At this point, also dogs of the control group were again moved into clean enclosures, shampooed twice and treated with ronidazole. Five, 12 and 19 days after the last treatment, the dogs in the control group tested negative for Giardia cysts and antigen. However, all animals had again positive results at later time points in at least one of the three applied diagnostic techniques within 33-61 days after treatment. Furthermore, all dogs had episodes of diarrhea (for 1-4 days) within 14-31 days after treatment and unformed feces during the whole experiment. The positive effect of ronidazole against Giardia infections in dogs could be confirmed in this study. In particular, the combination of ronidazole treatment combined with the disinfection of the environment and shampooing of the dogs was highly effective in reducing Giardia cyst excretion and may therefore constitute an alternative control strategy for canine giardiosis.  相似文献   

8.
Feline giardiasis: observations on natural and induced infections   总被引:4,自引:0,他引:4  
The excretion of Giardia sp cysts in the feces of naturally and artificially infected cats fluctuated sporadically, and cysts were undetectable several times during 7 weeks of observation. The mean prepatent period for Giardia infection in 7 cats was 9.6 days (range, 5 to 16 days). The amount of the cyst inoculum did not appear to affect the length of the prepatent period. Six of 11 cats had clinical signs consistent with those of giardiasis. Clinical signs and cyst excretion were eliminated after treatment with metronidazole or furazolidone. Moderate oral or parenteral doses of corticosteroids produced little, if any, alteration in the infection. Postmortem examination of 1 inoculated cat revealed Giardia trophozoites in the jejunum and upper portion of the ileum but not in the duodenum, lower portion of the ileum, cecum, or colon. Giardia cysts isolated from cat feces produced infection in Mongolian gerbils but not in C57BL/6J mice.  相似文献   

9.
The prevalence of cats shedding Giardia cysts (13.6%) in the present study was found to be higher than previously reported (1% to 11%) and may reflect a higher sensitivity for the diagnostic test used. The presence of Cryptosporidium spp. oocysts, coccidial oocysts, and a clinical history of chronic (>2 weeks) gastrointestinal signs were significantly associated with the presence of Giardia spp. cysts in the feces. There were no associations between the presence of Giardia spp. cysts and type of housing, acute gastrointestinal signs, vomiting, gender, source of cat (i.e., animal shelter versus private breeder), or gastrointestinal parasites other than Cryptosporidium spp. and intestinal coccidial agents.  相似文献   

10.
Giardiasis in a cattery   总被引:1,自引:0,他引:1  
Giardia sp infection was believed responsible for chronic, intermittent diarrhea in a group of 14 Persian cats. Seven of the cats were shedding Giardia sp cysts, and 6 of these cats had diarrhea at the time of fecal examination. Conversely, only 1 of 6 clinically normal cats in the group was shedding Giardia sp cysts. Cysts were not detected in feces of 2 cats with diarrhea. Cats less than or equal to 3 years old were more likely to be found shedding cysts. The parasite apparently was eradicated from the cattery by a combination of cage disinfection (1% sodium hypochlorite solution) and oral furazolidone treatment (4 mg/kg of body weight, BID for 5 consecutive days). During treatment, clinical signs resolved, and all cats remained clinically normal 2 months after treatment.  相似文献   

11.
OBJECTIVE: To identify potential pathogens in feces from llama and alpaca crias with diarrhea. DESIGN: Prospective observational study. ANIMALS: 45 unweaned crias with diarrhea. PROCEDURE: Fecal samples were evaluated for Eimeria spp, Giardia spp, Cryptosporidium spp, enteric viruses, and Salmonella spp. A questionnaire yielded information concerning herd management and presence of other affected camelids. RESULTS: 28 crias were < or = 31 days old, 11 were 32 to 62 days old, and 6 were 63 to 210 days old. Potential pathogens were isolated from feces from 32 of the 45 crias. A total of 39 potential pathogens were obtained, including coronavirus (n = 19 crias; 42%), Giardia spp (8; 18%), Eimeria spp (6; 13%), Cryptosporidium spp (4; 9%), rotavirus (1; 2%), and nematode ova (1; 2%). Salmonella spp were not isolated. Most crias from which potential pathogens were isolated were identified during outbreaks of diarrhea involving other camelids, although only coronavirus was isolated from crias identified during outbreaks involving adult camelids. Coronavirus was detected throughout the year, whereas protozoa were most commonly isolated during the fall and winter. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a variety of potential pathogens may be isolated from young crias with diarrhea. Many crias shed coronavirus, which may also have been affecting older camelids. Protozoa were isolated most often during wetter months, suggesting that crias born during these months may have greater exposure to protozoal pathogens.  相似文献   

12.
OBJECTIVE: To determine duration of infection and association of infection with diarrhea for dairy calves with naturally acquired cryptosporidiosis and giardiosis. DESIGN: Cohort study. ANIMALS: 20 Holstein calves on a single dairy farm. PROCEDURE: Fecal samples were collected 3 times/wk for the first 45 days after birth, then weekly until calves were 120 days old and examined for Giardia duodenalis cysts and Cryptosporidium parvum oocysts. Calves were monitored for diarrhea during the first 45 days after birth; during each episode of diarrhea, fecal samples were examined for parasitic, bacterial, and viral pathogens. RESULTS: All 20 calves shed Giardia cysts and Cryptosporidium oocysts at some time during the study. Mean ages at which Giardia cysts and Cryptosporidium oocysts were first detected were 31.5 and 16.3 days, respectively. Mean number of Giardia cysts in feces remained high throughout the study, whereas Cryptosporidium occysts decreased to low or undetectable numbers 2 weeks after infection. Eighteen calves had a total of 38 episodes of diarrhea during the first 45 days after birth. Giardia duodenalis was the only pathogen identified during 6 (16%) episodes, C parvum was the only pathogen identified during 9 (24%) episodes, and G duodenalis and C parvum were identified together during 10 (26%) episodes. CONCLUSIONS: Prevalences of giardiosis and cryptosporidiosis were high in these calves, and both parasites were associated with development of diarrhea. Cryptosporidium parvum was an important pathogen when calves were < 1 month old, but G duodenalis was more important when calves were older. Calves cleared C parvum infections within 2 weeks; however, G duodenalis infections became chronic in these calves.  相似文献   

13.
In this 90-day study, 60 male Holstein dairy calves were experimentally infected with Giardia duodenalis. Calves were randomly blocked by weight into treatment (N=30) and placebo (N=30) groups. Beginning on study Day 0, calves in the treatment group were administered an oral dose of 5mg/kg of fenbendazole once daily for three consecutive days. Calves in the placebo group received a daily oral treatment of 5 ml of saline for 3 days. These treatments were repeated on Days 30 and 60 of the study. Fecal samples were collected from calves once per week and examined for the presence of Giardia cysts. Calves were monitored daily for clinical signs of intestinal disease and all episodes of diarrhea recorded. Calves were weighed once per week and total feed intake, on a dry matter basis, was calculated daily. Following each treatment, the number of calves shedding Giardia cysts in the fenbendazole group was reduced (p<0.001) compared to the saline group. Also, calves in the fenbendazole group had fewer cysts (p<0.05) detected in their feces following treatment compared with calves that received saline. Within 2 weeks post treatment, the number of infected animals and fecal Giardia cysts returned to placebo levels. This pattern of reinfection was consistent after every treatment period. Calves receiving fenbendazole had fewer total days with diarrhea (p<0.01) and the average number of days each calf had diarrhea was reduced (p<0.05), compared to the placebo group. There were no differences in mean body weight, average daily gain, or feed intake between the treatment or placebo groups. This study demonstrates that fenbendazole is an effective treatment for giardiosis, resulting in a clinical benefit and reducing the number of infective cysts shed by calves. However, this treatment regime had no impact on production parameters and reinfection occurred rapidly in these calves.  相似文献   

14.
The present work investigated the occurrence of Giardia infection in Chinchilla lanigera reared in three Italian breeding facilities and determined their role as potential zoonotic reservoir. One hundred and four fecal samples were tested for the presence of Giardia spp. cysts using a Direct Fluorescent Assay (DFA). A high positivity rate (39.4%) was found despite all animals were asymptomatic at the time of sampling. Thirty-one positive samples were genetically characterized by sequence analysis of the ITS1-5.8S-ITS2 region of the Giardia ribosomal DNA. Assemblages B (29 isolates) and C (two isolates) were identified. These results showed that Giardia infection can be common in chinchillas, thus spurring further molecular epizootiological studies of the infection to assess the zoonotic potential or host specificity of their isolates, to determine the source of infections, to identify the routes of transmission, and to control the infection among animal populations.  相似文献   

15.
In various districts (Cantons) of Switzerland 815 calves (a few days up to 6 months old), 382 lambs and 20 young goats (both groups 1-6 months old) were selected randomly for a single coprological examination (flotation method) for Giardia infection. In average 26.6% of the calves, 29.8% of the lambs and 4 of 20 young goats excreted Giardia cysts. In 9 Cantons the percentages of cyst excretors among the calves varied between 15 and 32, but these differences were not significant. Further there were no significant differences in the frequency of cyst excretion between calves of 3 different breeds and 2 age groups (up to 3 months old and 3 to 6 months). The intensity of cyst excretion was high and varied in random samples between 4.1 x 10(3) and 3.0 x 10(5) cysts per g of faeces in calves and between 2.2 x 10(3) and 1.6 x 10(5) in lambs. In 5 of 7 farms where calves and lambs were maintained simultaneously both animal species were Giardia infected. As expected, trophozoites of Giardia isolates from calves and lambs belonged to the Giardia duodenalis type and could not be differentiated on a morphological basis. Giardia cysts from calves (average measurements: 13.7 x 9.1 microns) and lambs (13.8 x 9.2 microns) were indistinguishable both morphologically and morphometrically. The results indicate that Giardia infections are frequent and geographically widely distributed in calves and lambs in Switzerland.  相似文献   

16.
OBJECTIVE: To assess efficacy of Giardia vaccination as a treatment for giardiasis in experimentally infected cats. DESIGN: Original study. ANIMALS: 16 young-adult cats. PROCEDURE: Cats were experimentally infected by orogastric administration of Giardia cysts. On weeks 4, 6, and 10, cats in the treatment group (n = 8) were given Giardia vaccine SC. For the first 28 weeks after infection, 3 fecal samples from each cat were examined weekly for Giardia cysts, and cyst numbers were counted. Fecal consistency was scored daily for the duration of the study. Results from vaccinated and unvaccinated cats were compared by logistic regression. RESULTS: All cats became infected and were shedding Giardia cysts by the end of week 2. Throughout the study, diarrhea was rare and was mild and transient when it did occur. By week 28, 5 of 8 vaccinated cats and 7 of 8 control cats had patent Giardia infections. Magnitude of infection, based on number of fecal samples with cysts and number of cysts per sample, decreased progressively in both groups over time. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of 3 doses of a Giardia vaccine did not completely eliminate the organism from experimentally infected cats in the study period. Since clinical signs were minimal in both groups of cats, it could not be determined whether vaccination lessened severity of clinical disease. Results may have been negatively influenced by the large inoculation dose. Whether Giardia vaccination is an effective treatment for giardiasis in naturally infected cats remains to be determined.  相似文献   

17.
The performance of immunofluorescence microscopy (IF) and enzyme-linked immunosorbent assay (ELISA) in canine feces was evaluated. IF and Cryptosporidium ELISA detected 10(5)oocysts/g, while the detection limit for Giardia ELISA was 10(4)cysts/g. The Cryptosporidium ELISA showed 94% specificity but only 71% sensitivity. The Giardia ELISA correlated well with IF (sensitivity 100%, specificity 96%) and was capable of detecting animal specific Giardia duodenalis genotypes. Visual interpretation appeared appropriate for assessment of ELISA results. The proportion of positive samples and possible zoonotic character of Cryptosporidium and Giardia infections in 150 asymptomatic Finnish dogs from the Helsinki area were studied. The overall proportion of dogs positive for Cryptosporidium was 5% (7/150) and that for Giardia 5% (8/150). In dogs < or =12 months old, the corresponding proportions were 17% and 19% (n=36). Sequence analyses of the 18S rDNA gene identified the isolates as Cryptosporidium canis and animal specific genotypes of G. duodenalis (assemblages C-E), indicating restricted risk of zoonotic transmission.  相似文献   

18.
Eighteen cats, 3-6 months of age, bred and housed in a closed colony, were transferred from that colony and placed in separate stainless steel cages in a building designed for housing animals. At daily intervals, feces were collected from the litter pans in each cage, pans and cages were cleaned, and fresh food and water were provided. Beginning 4 weeks after the transfer, oocysts of Cryptosporidium were detected in the feces of two cats by brightfield microscopy. For the following 21 days, with minor exceptions, feces from each cat were collected daily and examined by immunofluorescence microscopy and by molecular methods that included DNA extraction, 18S rDNA gene amplification, and DNA sequence analysis. Within those 22 days, every cat was found to be infected with Cryptosporidium felis and excreted oocysts for 6-18 days. Eight of these 18 cats also excreted cysts of Giardia duodenalis Assemblage F, a genotype found only in cats. Six Giardia infections were concurrent during part of the patency with C. felis infections. Neither diarrhea nor other signs of illness were observed in any of the cats during this time. Because C. felis is zoonotic these findings suggest that care should be taken by veterinary health care providers and others in close contact with cats, even when cats appear healthy and asymptomatic.  相似文献   

19.
Giardia duodenalis and Cryptosporidium spp. infections, and the patterns of cyst and oocyst shedding, were observed in a herd of dairy calves in Ontario over a period of 3 mo. Cysts and oocysts were detected and enumerated in fecal samples using immunofluorescence microscopy; Giardia and Cryptosporidium DNA was detected using the polymerase chain reaction. The prevalence of G. duodenalis increased during the course of the study, reaching a peak of 93.1% when calves were 43 to 54 d old, and then decreased. Conversely, Cryptosporidium spp. prevalence was highest (75.9%) when calves were 11 to 22 d old, and subsequently decreased. The numbers of cysts and oocysts shed per gram of feces were positively correlated over time with the respective prevalence rates. Along with genotyping data, temporal changes in prevalence and shedding patterns should be considered when testing dairy calves for the presence and concentrations of cysts and oocysts, and when considering the potential for zoonotic transmission.  相似文献   

20.
Baylisascaris procyonis is a zoonotic parasite that has been documented in raccoons throughout much of the United States; however, no published information on its occurrence is available for the transition zone from the Great Plains to the Rocky Mountains. Because this parasite can cause neural larva migrans and diffuse unilateral subacute neuroretinitis in humans (as well as other hosts), a more complete understanding of the distribution of this parasite seems warranted for public health reasons. The purpose of this study was to begin to fill in the gaps in our knowledge of the distribution of B. procyonis in an area of the US where there is, currently, no published information available. Fifty-three raccoons were collected throughout eastern Colorado during 2007-2010. Forty-six were examined by necropsy and seven by fecal flotation. Age (11 juveniles, 25 adults) and sex (16 males, 19 females) of the raccoons were recorded when intact carcasses were available. When available, feces were further processed for the detection of Giardia and Cryptosporidium using a direct fluorescent antibody detection method. B. procyonis was found in 31 of 53 raccoons (58.5%, 95% CI=44.1%, 71.9%). Mean intensity was 11.7 with a range of 1-49 worms per infected individual. There was no significant difference between age or sex, and the presence of ascarids or the number of ascarids. Cryptosporidium spp. oocysts and Giardia spp. cysts were detected in 11/44 (25%; 95% CI: 13.2, 40.3) and 3/44 (6.9%; 95% CI: 1.4, 18.7) raccoons, respectively. The genotype of the Giardia present could not be determined. The genotype of five of six cryptosporidial isolates was 100% homologous to the skunk genotype while the sixth was 100% homologous to Cryptosporidium parvum. Based on these results, both B. procyonis and Cryptosporidium spp. appear to be prevalent in raccoons of eastern Colorado.  相似文献   

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