CRYPTOSPORIDIUM SPP. IN PET DWARF WINTER WHITE RUSSIAN HAMSTERS (PHODOPUS SUNGORIS SUNGORIS) IN CHINA.

Cryptosporidium spp. have been identified in a wide range of hosts, such as humans and domestic and wild animals, while less information about the prevalence of Cryptosporidium spp. in pet hamsters is documented. A total of 351 dwarf winter white Russian hamsters' fecal specimens were collected from 6 pet markets from the cities of Luzhou and Ziyang in Sichuan province in the southwestern part of China. The prevalence of Cryptosporidium spp. determined with nested-PCR amplification of the partial small-subunit (SSU) rRNA gene was 39.32% (138/351). The highest prevalence of Cryptosporidium spp. was in pet market 5 (79.49%, 62/78), followed by pet market 6 (38.64%, 17/44). The lowest prevalence of Cryptosporidium spp. was observed in pet market 3 (14.89%, 7/47). Statistically significant differences in the prevalence of Cryptosporidium spp. were observed among different pet markets (χ2 = 76.386, df = 5, P < 0.05), and a further post hoc test revealed that only pet market 5 was significantly different from other pet markets. Molecular analysis showed that 4 different Cryptosporidium species or genotypes were identified: Cryptosporidium parvum (n = 127), Cryptosporidium chipmunk genotype III (n = 6), Cryptosporidium andersoni (n = 4), and Cryptosporidium wrairi (n = 1). The identification of Cryptosporidium spp. was further tested with the 60-kDa glycoprotein (GP60) gene, and the positive rate was 29.7% (41/138). This is the first molecular report on Cryptosporidium spp. infection in dwarf winter white Russian hamsters in China. With C. parvum and C. andersoni being identified in both humans and pet hamsters, these findings suggest that pet hamsters may be potential reservoirs of zoonotic Cryptosporidium species and subtypes.

[Complicated forms of superinvasion opisthorchiasis: pathogenetic aspects].

Superinvasion opisthorchiasis is characterized by host growth retardation and weight reduction, which are due to the cleptoeffect of Opisthorchis felineus; metabolic disturbances, proliferative processes, accelerated collagen biosynthesis and biodegradation in the organs reflect parasite-host interactions as components of the system. The productive reactions of visceral pathology are initiated by the parasite's metabolites located in the liver, lung, heart, and testes.

Helminths collected from imported pet murids, with special reference to concomitant infection of the golden hamsters with three pinworm species of the genus Syphacia (Nematoda: oxyuridae).

A total of 210 individuals of 13 species belonging to 4 subfamilies of Muridae imported into Japan as pets were examined; 5 species of Syphacia (Nematoda: Oxyuridae), Aspiculuris tetraptera (Nematoda: Heteroxynematidae), and Rodentolepis nana (Cestoidea: Hymenolepididae) were collected. Concurrent infection with 3 pinworm species, Syphacia mesocriceti, Syphacia stroma, and Syphacia peromysci, was recorded for the first time in the golden hamster, Mesocricetus auratus. Syphacia mesocriceti was also identified in the desert hamster, Phodopus roborovskii, and S. peromysci was recovered from the fat-tailed gerbil, Pachyuromys duprasi, and the Cairo spiny mouse, Acomys cahirinus. From the pygmy mouse, Mus minutoides, an undetermined species closely resembling Syphacia megaloon and Syphacia ohtaorum, both parasitic in Mus spp., was collected. Females of another undetermined Syphacia sp. were observed in the greater Egyptian gerbil, Gerbillus pyramidum. All of the host-Syphacia associations, except S. mesocriceti in the golden hamsters, were recorded for the first time. It is suggested that overlapping breeding situations provided the opportunity for host switching by the pinworms.

High susceptibility of Djungarian hamsters (Phodopus sungorus) to the infection with Babesia microti supported by hemodynamics.

As the comparative study was carried out on the susceptibility by the pursuit of parasitemia among the Djungarian, Syrian, and Chinese hamsters as well as BALB/c mice infected with the Syrian hamster-adapted Babesia microti strain, and Djungarian hamsters showed the highest parasitemia among them. Then, the other hematological parameters were pursued in the Djungarian hamsters infected with the hamster-adapted B. microti strain. Remarkable symptoms observed were hemoglobinuria clinically, anemia hematologically, and splenomegaly macroscopically during all over the observation period for 24 weeks post infection (PI). Parasitemia began to rise at 2 weeks and peaked at 4 weeks PI. After that, parasitemia decreased gradually but was maintained with a level of about 10% on average until 24 weeks PI at the end of the experiment. A decrease in the RBC count, Hb, and PCV, and an increase in the reticulocyte and WBC counts due to the development of immature neutrophils, lymphocytes and monocytes were recognized together with a rise of parasitemia. The hamsters had macrocytic hypochromic anemia due to the increase of MCV and the decrease of MCHC in the growth phase of the parasite. It was considered that the Djungarian hamsters will be useful for the infection examination, isolation, maintenance, and passage of B. microti in laboratory.

[The first finding of a spontaneous gastric cryptosporidiosis infection in hamsters (Phodopus roborovskii Satunin, 1903)]. / První nálezy spontánní zaludecní kryptosporidiové infekce u krecíku (Phodopus roborovskii Satunin, 1903).

The desert hamster (Phodopus roborovskii Satunin, 1903) represents a new host of Cryptosporidium muris Tyzzer (1907), 1910. This very first finding was made in the laboratories of the National Veterinary Institute, Prague, Czech Republic. In September 1994 three 11-month and one 3-month desert hamsters were sent for laboratory examination. Parasitological examination post mortem of a 3-month desert hamster revealed "large" Cryptosporidium oocysts in excrements as well as in the contents of intestines. In all animals in which autopsy was carried out congestion of lungs, spleen and liver, acute catarrhal inflammation and flatulences in portions of gut were observed. Presence of morphologically identical oocysts of cryptosporidia was confirmed in the same group of desert hamsters also during parasitological reexamination carried out in October 1994. Applying the methods according to Breza (1957) and Pavlásek (1991) oocysts of the protozoon under study were detected in pooled samples of excrements of 3, 4, 5, 10 and 11-month animals. Two out of four live 2-3-month desert hamsters were infected naturally, both parents (10-11 months old), sent by the owner to our laboratory to be used for further observation. Both adult animals showed slight tremor, somnolence, rough hair and recumbent position, the male showed paresis of pelvic limbs. For four days in the laboratory conditions excrements of all six live desert hamsters, the interval being 2-12 hours, were examined and in four of them the finding of oocysts of the protozoon was repeatedly positive. Adult animals were euthanasied.(ABSTRACT TRUNCATED AT 250 WORDS)