Conjunctival cryptosporidiosis in a duck

Cryptosporidial conjunctivitis was detected histologically in one of 17 eight-week-old ducks during an investigation into the cause of conjunctivitis. Another 80 ducks were examined histologically for cryptosporidial conjunctivitis over the next few months. No further cases were detected. Because only one infected bird was detected, it was concluded that the cryptosporidial infection was an incidental finding rather than a primary infection.     

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.     

Fatal cryptosporidiosis in quail

Young quails kept in wire-floored cages experienced high mortality, beginning at age 5 days, from diarrhea that was unresponsive to antibiotic therapy. At necropsy, the small intestine had clear fluid content and the cecum was distended by brown foamy fluid. Histopathologic findings in the small intestine were shortened villi with detached enterocytes at the tip. Cryptosporidium sp. (confirmed by electron microscopy) were numerous in the microvillous border. Neither bacterial nor viral pathogens were detected. No infection was established in day-old chickens gavaged with feces and intestinal contents from infected quails. Thorough cleansing of the cages followed by application of commercial bleach prevented recurrence.     

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.     

鸡隐孢子虫病治疗试验

隐孢子虫病 ( Cryptosporidiosis)是一种流行于世界各地的人畜共患病 ,已对人畜健康造成极大危害 ,并日趋引起医学及兽医学界学者的重视。近年来 ,国内外许多学者在研究隐孢子虫的各种生物学属性的同时 ,对该病的治疗进行了广泛探索。先后以广谱抗生素、磺胺类、抗原虫及蠕虫性     

Intestinal cryptosporidiosis in turkeys in Iran

Naturally occurring cryptosporidiosis is reported in turkey poults suffering from diarrhoea and unthriftness in Iran. Histological and ultrastructural studies revealed high number of Cryptosporidium developmental stages mainly located in the mid and terminal portions of small intestine of the poults. Other portions of the intestinal tract were less frequently infected. Oocyst shedding was detected only in 29% of the histologically positive birds. Based on host species, clinical signs, pathology and tissue location of the parasites, Cryptosporidium meleagridis was most likely responsible for these infections. This parasite was also reported recently in a child with diarrhoea in Iran.     

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.     

Enterocolitis in spontaneous cryptosporidiosis infections in calves

The pathology of lesions in the intestines of 48 calves with spontaneous cryptosporidiosis was studied by histological examination and by scanning electron-microscopy (SEM). The animals were 7 to 21 days old, emergency-slaughtered mostly for dehydration and diarrhoea. Identical lesions were observed in the jejunum and ileum. The villi, often infected by cryptosporidia on a mass scale, were shortened, atrophic, markedly curved and shrunk in their ultrastructure, often as a result of the regression of groups of enterocytes with cryptosporidia, the adjacent tissue being affected, at the same time, by nodular hyperplasia. The enterocytes harbouring the protozoans exhibited cuboidal up to squamous metaplasia; in ultrastructure they had not hexagonal shape and showed signs of microvillus regression. The cryptosporidiosis of the small intestine was always accompanied by hyperaemia and inflammatory reactions in lamina propria, mostly non-purulent, with numerous eosinophils. Signs of typhlitis in the caecum--more frequent and intensive than in other parts of the large intestine infected by cryptosporidia--were characterized, in most cases, by lesions in the covering epithelium and by mostly non-purulent inflammatory infiltration with a large admixture of eosinophils in lamina propria. No inflammatory lesions were found in the colon and rectum. Severe cryptosporidial infections of large parts of intestine and the nature of pathological lesions lead to a considerable reduction in the total absorption surface of the intestine and are potential causes of diarrhoea from malabsorption.     

Sheep management and cryptosporidiosis in central Mexico

To establish the association between sheep farm management practices and cryptosporidiosis in Central Mexico, 37 farms were invited and questionnaires answered by owners. Faeces samples were taken from lambs under 3 months old and ewes in the farms. Parasites were identified by modified Ziehl-Neelsen stain. Questionnaire included: general farm information, facilities characteristics, facilities cleaning measures, water use and farm and animal management practices. Farms were grouped in a low (￡3,37%), medium (3.38-49.9%) and high basis (³50%) according to prevalence. Associations (OR) were calculated according to positivity, compared by chi-square test. A general prevalence of 34,33% was found. Five variables showed statistical significance (p<0.05). Associations found were: use of bed, grazing place, and bottle cleaning. The only association found between management practices and cryptosporidiosis that could represent a risk was the grazing place. This report is the first one in the country regarding predisposing conditions for cryptosporidiosis.     

Therapy and prevention of cryptosporidiosis in animals

Cryptosporidiosis is a common gastro-intestinal illness in animals and man worldwide. The disease is devastating in immune-suppressed individuals but self-limiting in competent hosts. The infectious stages of the organism (oocysts) are shed in the faeces of affected individuals, survive in adverse environmental conditions and spread by direct contact or through contaminants (food, water). Due to the robustness of the oocysts, their tenacity, tiny size, and resistance to common disinfectants, the parasite is difficult to eradicate from contaminated environments. To obtain sufficient control both treatment of infected hosts and inactivation of oocysts are necessary. Several drugs are commonly used to treat cryptosporidiosis in man and very few in animals but none of them are completely effective in terms of both clinical and parasitological response. Only a few chemical agents are able to inactivate oocysts in the environment including water treatment plants but their application has certain limitations. Therefore, control of cryptosporidiosis remains a global challenge in both veterinary and human medicine. Extensive research has been performed on suitable drugs and disinfectants. Thousands of agents have been tested both in vivo and in vitro. Some are excitingly active in vitro but exhibit poor or no response in clinical trials. Currently, no single or combined drug therapy has proven to be completely effective against this disease. This article will focus on therapy and prevention of cryptosporidiosis in animals including perspectives for new drugs.     

Urinary tract cryptosporidiosis in commercial laying hens

Formalin-fixed kidney tissues from adult egg-laying chickens in two houses of an egg-production complex in the upper Midwest were submitted to Iowa State University for histopathologic examination. An increased incidence of visceral gout, average daily mortality 1%-2% higher than expected, and egg production within normal limits were observed in both houses. Numerous developing stages of Cryptosporidium were observed on the apical surface of epithelial cells lining renal collecting tubules and ureters. Scanning and transmission electron microscopy were used to visualize colonization of cryptosporidia, disruption of microvilli, and exfoliation of parasitized epithelial cells. Lymphoplasmacytic infiltration in the wall of ureters and hyperplasia of parasitized epithelial cells resulted in partial obstruction of ureters, which may have induced visceral gout in affected hens. This is the first report of urinary tract cryptosporidiosis occurring in adult hens in a modern commercial egg-production facility.     

Coccidiosis and cryptosporidiosis in sheep and goats

The protozoan diseases, coccidiosis and cryptosporidiosis, are important enteric diseases of sheep and goats, resulting in diarrhea, inefficient weight gains, and occasionally death. Coccidiosis is a widespread, serious economic disease affecting animals who are preweaned, recently weaned, or in unsanitary, stressful, or crowded conditions, as well as after entering feedlots. The Eimeria species in sheep and goats are relatively host specific. Control is accomplished through sanitation and by incorporating one of the modern coccidiostats, such as lasalocid or decoquinate, in feed or salt to ensure an intake of approximately 1 mg of drug per kg of body weight per day for at least 30 consecutive days. Prevention and control of coccidiosis results in significantly greater weight gains and production, whereas disease with or without treatment is likely to result in inefficient production and economic loss to the producer. Cryptosporidiosis, caused by Cryptosporidium parvum, is primarily a disease of lambs and kids less than 30 days of age and is usually a milder disease than coccidiosis. Infective oocysts are passed in feces and are transmitted by oral ingestion. Oocysts readily infect a variety of animals, including humans. Cryptosporidiosis is a prevalent disease in neonatal ruminants and in humans. Effective treatments are not available, but because the disease is usually mild and self-limited, supportive care, primarily hydration, is important. Control is strict sanitation and quarantine of sick animals. Disinfection of contaminated housing with ammonia or formalin will kill the oocysts. The cyst-forming coccidia diseases, toxoplasmosis and sarcocystosis, utilize two hosts in their life cycles: sheep or goats and carnivores. Abortions and reproductive failures are major manifestations of disease. Control is through elimination of carnivore feces from the premises through management.     

隐孢子虫病的研究概况

隐孢子虫病(Cryptosporidiosis)是一种由隐孢子虫感染引起的人兽共患的肠道原虫病。该病以持续性腹泻为主要临床表现。感染隐孢子虫后，哺乳动物常表现为腹泻；禽类表现为呼吸困难和腹泻；婴幼儿及免疫功能低下则多发致死性肠炎。该病对畜牧业的发展和人类的健康带来了严重的影响。世界卫生组织(WHO)于1986年将人的隐孢子虫病列为艾滋病(AIDS)的怀疑指标之一，     

牛隐孢子虫和隐孢子虫病的研究进展

从牛隐孢子虫病的病原分类、内生发育史、体液免疫和细胞免疫、流行病学特点、诊断、防治等几方面阐述了牛隐孢子虫和隐孢子虫病的研究现状，总结了前人对牛隐孢子虫3个有效种的生物学特性研究的结果，为进一步了解牛隐孢子虫病的流行病学及有效防制该病提供了参考。     

Pulmonary cryptosporidiosis in simian immunodeficiency virus-infected rhesus macaques

Cryptosporidiosis is a common opportunistic infection in the gastrointestinal tract of human and nonhuman primates with AIDS. Pulmonary infection associated with Cryptosporidium spp. has not been previously reported in monkeys. Two macaques experimentally infected with simian immunodeficiency virus (SIV) had lesions containing cryptosporidial organisms involving the trachea, lungs, bile ducts, pancreas, and intestine. The pulmonary sections revealed moderate to severe bronchopneumonia associated with cryptosporidiosis. Numerous 2-4 microm oval Cryptosporidium spp. organisms were present in the cytoplasm of alveolar macrophages, multinucleated giant cells, and intestinal epithelial cells. Giant cells were positive for SIV by in situ hybridization. These are the first reported cases of cryptosporidiosis with involvement of pulmonary parenchyma in SIV-infected macaques.