Experimental infection of cats with Tritrichomonas foetus.

OBJECTIVE: To determine whether infection with Tritrichomonas foetus causes diarrhea in specific-pathogen-free or Cryptosporidium coinfected cats. ANIMALS: 4 cats with subclinical cryptosporidiosis (group 1) and 4 specific-pathogen-free cats (group 2). PROCEDURE: Cats were infected orogastrically with an axenic culture of T. foetus isolated from a kitten with diarrhea. Direct microscopy and protozoal culture of feces, fecal character, serial colonic mucosal biopsy specimens, and response to treatment with nitazoxanide (NTZ; group 1) or prednisolone (groups 1 and 2) were assessed. RESULTS: Infection with T. foetus persisted in all cats for the entire 203-day study and resulted in diarrhea that resolved after 7 weeks. Group-1 cats had an earlier onset, more severe diarrhea, and increased number of trichomonads on direct fecal examination, compared with group-2 cats. Use of NTZ eliminated shedding of T. foetus and Cryptosporidium oocysts, but diarrhea consisting of trichomonad-containing feces recurred when treatment was discontinued. Prednisolone did not have an effect on infection with T. foetus but resulted in reappearance of Cryptosporidium oocysts in the feces of 2 of 4 cats. During necropsy, T. foetus was isolated from contents of the ileum, cecum, and colon. Tritrichomonas foetus organisms and antigen were detected on surface epithelia and within superficial detritus of the cecal and colonic mucosa. CONCLUSIONS AND CLINICAL RELEVANCE: After experimental inoculation in cats, T. foetus organisms colonize the ileum, cecum, and colon, reside in close contact with the epithelium, and are associated with transient diarrhea that is exacerbated by coexisting cryptosporidiosis but not treatment with prednisolone.     

Cryptosporidiosis in neonatal calves: 277 cases (1986-1987)

From January 1986 through December 1987, 277 cases of cryptosporidiosis in calves were diagnosed by the South Dakota State University Diagnostic Laboratory. Cryptosporidium sp was the only pathogen identified in 142 (51.3%) of the calves. Concurrent infections with rotavirus, coronavirus, Escherichia coli, Salmonella sp, bovine viral diarrhea virus, or other pathogens were identified in the remaining 135 calves. After elimination of cases involving autolyzed specimens or calves with chronic diarrhea, records of 11 calves with acute, severe cryptosporidiosis were identified in which Cryptosporidium sp was the only pathogen.     

Cryptosporidium species screening using Kinyoun technique in domestic cats with diarrhea

Cryptosporidium is a coccidian that can lead to diarrhea, especially in immunosuppressed individuals. Retroviruses are considered a primary cause of immunosuppression in cats. Fecal specimens and blood collected from the 60 cats were evaluated for the presence of acid-fast cryptosporidia in three consecutive stool samples and for feline leukemia virus (FeLV) antigen and feline immunodeficiency virus (FIV) antibody by ELISA testing. Five animals (8.33%) shedding oocysts were found, one was both FIV- and FeLV-negative and four were FeLV-positive.     

Intestinal cryptosporidiosis in chickens

In a retrospective examination of histopathology reports from Aug. 1, 1985, through Sept. 31, 1987, 10 cases of small- or large-intestinal cryptosporidiosis (not epithelial cryptosporidiosis of the bursa of Fabricius) were found in chickens. Infection was evenly distributed among young chickens. Incidence of intestinal cryptosporidiosis increased during 1987. Although all infected birds were clinically ill, signs or gross lesions of intestinal disease were not always present. In all cases, mild to marked histologic lesions were associated with Cryptosporidium sp.; however, intestinal tracts were not cultured for other infectious agents. The numbers of Cryptosporidium sp. and character of inflammatory response were not significantly correlated. A difference (P = 0.01) among intestinal segment (small vs. large) infection with Cryptosporidium was seen. Light-microscopic appearance and organ distribution of Cryptosporidium sp. suggest that in addition to C. baileyi, other Cryptosporidium species infect chickens. Until the diagnostic procedure for outbreaks of gastrointestinal disease in poultry routinely includes histopathology, fecal flotation, and virus, bacteria, and chlamydia cultures, and until species of Cryptosporidium are isolated, identified, reported, and investigated experimentally, the importance of intestinal cryptosporidiosis in chickens will remain unknown.     

隐孢子虫病及其在牦牛中的流行现状

隐孢子虫病是由隐孢子虫寄生于人或动物所引起的常见寄生虫病,其主要症状为腹泻,是一种人兽共患病,不仅对畜牧业经济生产造成损失,也威胁着人类健康。论文从隐孢子虫病的病原学、临床症状、病理变化、诊断与防控以及该病在牦牛中的流行情况等方面进行综述,可为牦牛隐孢子虫病的研究提供参考。     

Diarrhea associated with small-intestinal cryptosporidiosis in a budgerigar and in a cockatiel

Small-intestinal cryptosporidiosis has not been described in budgerigars or cockatiels. Organisms of the genus Cryptosporidium were found during histologic examination of segments of small intestine from a budgerigar with chronic weight loss and from a cockatiel that died acutely. Parasitism was accompanied by non-purulent inflammation (lymphocytes and plasma cells predominated). Bacterial and viral pathogens were not isolated. The death of the budgerigar was attributed to malassimilation interpreted to have been caused by Cryptosporidium. The cause of death in the cockatiel was inhalation pneumonia. Because the index of suspicion for cryptosporidiosis was low, samples for isolation of Cryptosporidium were not collected. In the future, cryptosporidiosis should be included as a differential diagnosis for weight loss and death in pet birds, and isolation and speciation of Cryptosporidium sp. should be attempted and reported.     

Giardiasis and cryptosporidiosis in ruminants.

Although they differ considerably with respect to their biology, both Giardia duodenalis and Cryptosporidium parvum are common in ruminants, whereas Cryptosporidium andersoni is not. G. duodenalis infections are acquired during the first few months of life, tend to be chronic, and may be a production-limiting disease of ruminants. C. parvum infections remain an important cause of diarrhea in neonatal ruminants. Abomasal cryptosporidiosis, caused by C. andersoni, is an emerging disease of cattle that may affect both beef and dairy herds. This article reviews the life cycles, production impacts, treatments, controls, and zoonotic potentials of these important ruminant parasites.     

Observations on the epidemiology of bovine cryptosporidiosis in India

The significance of Cryptosporidium as a causative agent of diarrhea has been assessed in bovine for a period of 2 years. A total of 940 faecal samples (470 samples in each year) both from diarrhoeic and non-diarrhoeic bovine (0-12 months age) were examined during three different seasons (rainy season, summer and winter). Overall Cryptosporidium was detected in 17.46% and 18.04% cases in first and second year, respectively. Out of 50.21% diarrhoeic and 49.79% non-diarrhoeic cases Cryptosporidium was detected in 26.79% and 8.13% in first year and 27.49% and 8.59% in second year. Year did not have any significant effect on the occurrence of cryptosporidiosis in bovine during this study period. The prevalence of cryptosporidiosis, both in diarrhoeic (61.64%) and non-diarrhoeic (47.22%) cases was highest in 0-1-month age group (P<0.01). Such a high percentage of cryptosporidiosis in clinically asymptomatic animals indicated that the particular age group of animals might be reservoir for the parasite. During this study period highest prevalence was recorded in rainy season (27.55%) followed by summer (16.99%) and winter (8.71%) (P<0.01). A total of 166 positive cases were genotyped. Molecular characterization of bovine cryptosporidiosis has been carried out by PCR-RFLP analysis of SSU rRNA gene and results indicated that Cryptosporidium parvum mainly responsible for diarrhea in bovine in India.     

Ocular disease in FeLV-positive cats: 11 cases (1981-1986).

A total of 147 cats positive for FeLV were retrospectively studied to determine the incidence of ocular disease. Of those cats, 97 had clinical cases of the disease and 50 were artificially infected with the virus. The incidence of ocular disease among FeLV-positive cats with clinical signs of disease was less than 2%, and represented less than 0.1% of the total feline cases for the 5-year period studied. The only ocular findings that could be associated with FeLV were pupillary and motility abnormalities. Retinal hemorrhage and subsequent degeneration found in experimentally infected and naturally infected cats were secondary to profound anemia, which was secondary to FeLV infection. On the basis of the literature and our findings, FeLV is not a major cause of primary or secondary ocular disease in the cat. Anterior uveal disease (iris bombé) was detected in 1 of 147 FeLV-positive cats, and the incidence of secondary infectious disease was zero.     

Cryptosporidium infection as a cause of calf diarrhea

Cryptosporidiosis is a self-limiting protozoal disease of the intestinal tract. Although identified as possible agents of calf diarrhea less than 15 years ago, Cryptosporidium spp. are now believed to be common in calves and in many other host animal species worldwide. Recent literature on all aspects of cryptosporidiosis in calves is reviewed, predicaments in diagnosis and management are discussed, and public health concerns are raised.     

Sporadic cryptosporidiosis in a rural population is asymptomatic and associated with contact to cattle

Fecal samples each followed by a completed questionnaire were obtained from 233 persons representing 80 households. Using the formalinether concentration method combined with the acid-fast staining oocysts of Cryptosporidium were found in 7 (3 %) persons. 63 persons had contact to cattle, and asymptomatic cryptosporidiosis was diagnosed in 6 of them. Cryptosporidiosis was not found in any of the 51 persons with contact to some other animal but not cattle, and none of the 7 Cryptosporidium positive persons had been traveling abroad. We also obtained fecal samples from 15 calves from 7 households. Six of the calves (40 %) harbored Cryptosporidia and manifest enteritis was detected in those under age of 1 month. Five out of 14 farms had problems of neonatal calf diarrhea. Human cryptosporidiosis was more frequent on such problem farms. The results indicate that in rural population, human cryptosporidiosis is mainly asymptomatic and occurs mainly in residents of cattle-rearing farms.     

Murine monoclonal antibodies cross-reactive with feline peripheral blood mononuclear cells

Twelve murine monoclonal antibodies (MAB), specific for canine, human, and mouse cell surface determinants on lymphohemopoietic cells, were tested for reactivity (using indirect immunofluorescence) with peripheral blood mononuclear cells (PBMC) from 3 normal cats and 3 FeLV-positive cats with lymphoblastic leukemia. MAB DLy6 and 1H3, specific for canine lymphocytes, MAB HB57S, specific for human mu(IgM) chain, MAB J-118 40.164.3 and H81.98.71, specific for murine and human Ia, all had higher binding levels with PBMC from FeLV-positive cats compared to normal cats. Two MAB (S-78, S-24), specific for human class I determinants, cross-reacted with PBMC from both groups of cats. This panel of MAB may be useful for characterizing immunologically reactive cell subsets in normal as well as retrovirus-diseased animals.     

Gastrointestinal cryptosporidiosis in a puppy

An 8-week-old female Yorkshire terrier with a history of weakness, diarrhea and intestinal isosporiasis was euthanized and a post mortem examination performed. Histologically, there was severe gastrointestinal cryptosporidiosis, severe intestinal isosporiasis and thymic lymphoid depletion. PCR revealed visible bands for the actin and 18S rRNA genes but not for the acetyl CoA synthetase gene for Cryptosporidium spp. The PCR product for the actin gene was sequenced and found to have a 97.6-99.8% similarity to that of Cryptosporidium canis. To our knowledge, this is the first report of gastric cryptosporidiosis in a canine.     

Cryptosporidiosis in People: It's Not Just About the Cows

Cryptosporidiosis is one of the most common causes of infectious diarrhea in people. Although dairy calves are high-risk hosts, the role of other livestock, pets, and humans in the disease should not be underestimated. Some Cryptosporidium species and strains are specific to people, others are specific to animals while some are zoonotic pathogens. Cryptosporidium hominis is the species responsible for the majority of human cases in the United States, Sub-Saharan Africa, and Asia, while Cryptosporidium parvum accounts for more human cases in Europe and particularly in the United Kingdom. A deeper understanding of Cryptosporidium host range, reservoirs, and transmission is needed to develop preventive strategies to protect the general public.     

A rare Cryptosporidium parvum genotype associated with infection of lambs and zoonotic transmission in Italy

An outbreak of cryptosporidiosis occurred in a mixed sheep/cattle farm of Central Italy in October 2011. A total of 450 ovines (250 sheep and 200 lambs) and 140 bovines (130 cows and 10 calves) were housed in two separated units, at the time of the outbreak. About half of the lambs had diarrhea due to Cryptosporidium sp. with a mortality rate of 80%; calves were not infected. Genomic DNA was extracted from an archived slide and from fecal specimens, and the parasite was identified as Cryptosporidium parvum by PCR and sequence analysis at the CpA135 gene. Genotyping at the GP60 gene showed the presence of a very rare genotype, IIaA20G2R1. Shortly after the outbreak was identified, the son of the farm's owner, aged 18 months, experienced an acute gastroenteritis and was hospitalized due to recurrent episodes of diarrhea, fever, vomiting and lack of appetite. The feces tested negative for bacteria and viruses, whereas cryptosporidiosis was diagnosed by microscopy and an immunochromatographic test. Molecular typing identified the C. parvum genotype IIaA20G2R1 in the feces of the child. This is the first case of transmission of cryptosporidiosis in Italy involving lambs as source of oocysts infectious to humans.     

Duration of naturally acquired giardiosis and cryptosporidiosis in dairy calves and their association with diarrhea

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.     

Secondary lactose intolerance in a neonatal goat

A 2-week-old Toggenburg kid was evaluated for persistent diarrhea and poor body condition. The herd had high morbidity and mortality associated with diarrhea in neonatal kids. Lactose intolerance was diagnosed on the basis of results of a lactose tolerance test and glucose absorption test. Clinically normal herdmates were used as control animals. The kid responded to lactase supplementation. Cryptosporidium organisms were detected in feces of several affected kids during episodes of acute diarrhea. Lactose intolerance was presumed to have developed secondary to intestinal cryptosporidiosis.     

The presence of leukaemia (lymphosarcoma) and feline leukaemia virus (FeLV) in cats in The Netherlands

To study the presence and spread of feline leukaemia virus (FeLV) in The Netherlands, seven different groups of cats were examined. The indirect fluorescent antibody (IFA) test was used to detect FeLV-antigen in blood smears. Of cats with lymphosarcoma/leukaemia 73.2% were positive and 32.4% with infectious peritonitis were positive. Only one of sixty-six cats with other tumours–a cat with mammary carcinoma–was positive.
Forty-two (7.5%) of 557 cats with various complaints were positive for FeLV-antigen. The IFA-test appeared to be an important diagnostic supplement.
Of all stud males which had had contact with FeLV-positive cats 24.7% were positive for FeLV-antigen, whereas all stud males which had not had this contact, were negative.
There was a distinct difference between the percentages of FeLV-positive individuals in the groups of cats which had had (20.6%) and which had not had (0.4%) contact with FeLV-positive cats.
From the follow-up study it was found that 67.3% of the FeLV-positive cats died from, or were destroyed because of, FeLV-associated diseases within a period of 20 months.     

Prevalence of cryptosporidiosis in dogs and human beings in San Bernardino County, California

Fecal specimens from 200 stray dogs impounded at the San Bernardino City and County animal shelters were screened for Cryptosporidium sp oocysts, using the auramine-rhodamine fluorescent staining procedure. The University of California, Los Angeles acid-fast stain was used for confirmation. Only 4 (2%) dogs were passing cryptosporidial oocysts. Likewise, stool specimens from 664 people were submitted to the San Bernardino County Department of Public Health Laboratory for routine parasitologic examination and were screened for Cryptosporidium sp. Cryptosporidial oocysts were detected in 20 human fecal specimens (3.01%). On the basis of these findings, it appears that the human and canine populations of San Bernardino County are at low risk for development of cryptosporidiosis at this time.     

The relationship of Cryptosporidium sp. infection of the bursa of Fabricius, intestinal tract, and respiratory system of chickens in Georgia, 1974-1988

During 1974-1984, cryptosporidiosis was diagnosed in slightly more than 1% (63/6050 = 1.04%) of histopathology reports on chickens and turkeys made at two Georgia diagnostic laboratories. During 1985-1988, cryptosporidiosis was diagnosed in almost 6% (157/2622 = 5.99%) of histopathology reports on chickens and turkeys made at the two laboratories. Intestinal and respiratory Cryptosporidium sp. infections have increased significantly (p less than 0.01) with time. During the same period, there was no statistical pattern for bursa of Fabricius Cryptosporidium sp. infections, and there was no relationship between the incidence of bursal infections and the incidence of either respiratory or intestinal infections.