Endoparasites of Rodents and Their Zoonotic Importance in Germi,Dashte–Mogan,Ardabil Province,Iran

Background

In order to verify the infectivity of rodents with endoparasites in Germi (Dashte-Mogan, Ardabil Province) the current study was undertaken.

Methods

Using live traps, 177 rodents were trapped during 2005–2007. In field laboratory, all rodents were bled prior to autopsy, frozen at −20°C, and shipped to the School of Public Health, Tehran University of Medical Sciences, Iran. In parasitological laboratory, every rodent was dissected and its different organs were examined for the presence of any parasite. Blood thick and thin smears as well as impression smears of liver and spleen were stained with Geimsa and examined microscopically.

Results

Two species of rodents were trapped; Meriones persicus (90.4%) and Microtus socialis (9.6%). The species of parasites found in M. persicus and their prevalences were as follows: Hymenolepis diminuta (38.8%), Hymenolepis nana (2.5%), Trichuris sp.(40.6), Mesocestoides larva (=tetrathyridium) (3.1%), Capillaria hepatica (6.9%), Moniliformis moniliformis (11.3%), Syphacia obvelata (2.5%), Taenia endothoracicus larva (0.6%), Physaloptera sp. (0.6%), Dentostomella translucida (0.6%), Heligmosomum mixtum (0.6%), Strobilocercus fasciolaris (0.6%),and Aspiculuris tetraptera (0.6%). The species of parasites found in M. socialis and their prevalences were as follows: H. diminuta (17.6%), Trichuris sp. (5.9%), Mesocestoides larva (5.9%), S. obvelata (11.8%), S. syphacia (11.8%), H. mixtum (17.6%), and Aspiculuris tetraptera (11.8%). There were no statistical differences between male and female for infectivity with parasites in either M. persicus or M. socialis. No blood or tissue protozoan parasite was found in any of the rodents examined.

Conclusion

Among different species identified, some had zoonotic importance. Therefore, the potential health hazard of these species needs to be considered to prevent infectivity of humans.     

Comparison of calbindin D-28K immunoreactivity in superficial pineal bodies of mongolian gerbil and rat

Summary Immunocytochemical reaction for demonstration of calbindin D-28K has been performed in superficial pineal bodies of the Mongolian gerbil (Meriones unguiculatus) and the rat. Whereas in the Mongolian gerbil there were no clearly expressed calbindin immunoreactive cells, these were numerous in the rat pineal body. Here the calbindin-positive cells — probably pinealocytes — were disposed along capillaries. In view of the role of calbindin in binding and transporting calcium and regulating its intracellular levels, the absence of this protein in the gerbil pineal body has been interpreted as signifying the inability of pinealocytes to eliminate intracellular calcium with possible consequent formation of acervuli.Dedicated to Prof. Dr. Johannes Lang on the occasion of his 5th birthday     

鄂尔多斯荒漠草原鼠类群落的演替及疫源地宿主的多样性

鄂尔多斯荒漠草原30多年来鼠类的群落组成,由以草原黄鼠为主、长爪沙鼠次之,渐变为以长爪沙鼠为主,子午沙鼠和草原黄鼠次之。引起鼠类群落演替主要是人类经济活动的结果。动物鼠疫流行亦引起群落组成的变化,致使对鼠疫抗性较高的子午沙鼠数量渐增。动物鼠疫流行前的调查表明,4类生境中以长爪沙鼠的数量最多。鼠疫流行,引起长爪沙鼠数量从多到少急剧变化。     

肠阿米巴病的长爪沙鼠动物模型

剖腹后,将多栖培养的溶组织内阿米巴滋养体接种到长爪沙鼠盲肠内。接种后7～20 d 检查受试动物的肠内容物及肠、肝、脾、肠系膜淋巴结的病理组织学变化。16只受试动物有12只受染,其中7只出现盲肠病变,主要表现为粘膜表面縻烂,肠壁各层均有巨噬细胞和淋巴细胞浸润。其中1鼠的肠系膜淋巴结出现小灶状坏死,肝脏出现多发性小阿米巴脓肿。     

Parvalbumin disappears from GABAergic CA1 neurons of the gerbil hippocampus with seizure onset while its presence persists in the perforant path

Mongolian gerbils are epilepsy prone animals, a trait observable at the behavioural level during the 2nd month of life. As a unique species difference, gerbils express the calcium-binding protein parvalbumin (PV) in the perforant path from the entorhinal cortex to the hippocampus. In this study, we determined the time of appearence of PV in the layer II neurons of the entorhinal cortex and the perforant path terminals in gerbils between post-natal days 30 and 50. Signs of low grade seizures were observed in few animals from P40 onward. PV stain in the entorhinal cortex and perforant path terminals was already detectable at P30, well before the onset of behavioural seizures and did not change with age. It is suggested that the presence of PV in this pathway may be related to the generation early in life of an epileptogenic focus in the limbic forebrain. Altered inhibitory hippocampal circuits have also been suggested as a cause of seizures in the gerbil. Therefore, we quantitated hippocampal GABA- immunoreactive neurons and the PV-immunoreactive subpopulation. A group of gerbils with a high density of stained pyramidal interneurons in CA1 and one lacking PV-stained perikarya could be distinguished at P40 and P50. The density of GABA-immunoreactive nerve cells however, remained the same in both groups and through the ages studied. Thus, perikaryal PV is lost from intact GABAergic nerve cells at the same time as behavioural seizures are observed. The loss of PV from GABAergic neurons may affect their functional properties and be instrumental for the maintainance of behavioural seizures.     

二连国境口岸鼠间鼠疫的监测与检疫对策

作者于1992年6～9月，对二连口岸进行鼠间鼠疫监测，从该地区东部盐池附近1只自毙长爪沙鼠、1只活长爪沙鼠及1只活达乌尔黄鼠各检出1株鼠疫菌，并对目前该口岸地区鼠类种群组成、鼠密度、主要寄生蚤在宿主间的交换和转移作了调查，同时提出今后检疫对策。     

The medial and lateral cell groups of the sexually dimorphic area of the gerbil hypothalamus are essential for male sex behavior and act via separate pathways

Male reptiles, birds and mammals do not copulate if the medial preoptic area (MPOA) is destroyed but the MPOA cell groups necessary for male sexual behavior were not known. Here, two cell groups essential for copulation are identified in the sexually dimorphic area (SDA) of the gerbil (Meriones unguiculatus) MPOA. Bilateral cell-body lesions of either the medial or lateral SDA eliminated mating in sexually experienced male gerbils given testosterone. Nearby MPOA lesions did not. The medial and lateral SDA affect sex behavior via separate pathways since lesioning the medial SDA on one side of the brain and the lateral SDA on the other did not stop sexual behavior.     

长爪沙鼠种群年龄指标的主成分分析

本文采用生成分分析法,对内蒙古地区长爪沙鼠的体重、体长、尾长、颅全长、颅基长、鼻骨长、腭长、上齿列长、齿隙长、听泡长、听泡宽、颧宽、眶间宽、后头高、后头宽15项指标进行了二维排序。结果表明:颅基长是长爪沙鼠雄、雌鼠最具代表性的年龄指标;简易可行指标,雄鼠为体重,雌鼠为体长,亦可用于年龄划分。     

动物鼠疫静息期降水与长爪沙鼠种群的主成分回归关系

根据鄂尔多斯荒漠草原1981～1986年四季降水、长爪沙鼠4～5月、10～11月密度资料,利用主成分回归分析,给出两种不同条件下预报鼠密度的数学模型。     

Acanthocheilonema viteae : vaccination with irradiated L3 induces resistance in three species of rodents (Meriones unguiculatus, Mastomys coucha, Mesocricetus auratus)

Three species of rodents were immunized with 50 irradiated (35 krad) stage‐3 larvae (L3) of the filaria Acanthocheilonema viteae and challenged with an infection of normal L3. The immunization induced a significant reduction of the worm burden developing from the challenge infection in all host species, the jird ( Meriones unguiculatus ), the multimammate rat ( Mastomys coucha ) and the golden hamster (Mesocricetus auratus). The induced resistance was highest in jirds (92.5±9.7) followed by golden hamsters (59.4±26.6) and multimammate rats (55.1±40.4). The time course of antibody response against antigens of L3, adult worms and microfilariae, as studied by ELISA, showed quantitative and qualitative differences between the species. The antibody response against L3 antigens in immunoblots was similar in all species. Only one of the golden hamsters developed an antibody response against the surface of vector derived L3, while sera of jirds and multimammate rats did not react with L3 surface.