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1.
The products of the microbial activity in the large intestine are an important source of energy for herbivores. A previous study showed differences in caecal methanogenesis and short-chain fatty acid (SCFA) profiles between brown hares and domestic rabbits. The present study was performed on animals which were offered the same diet to eliminate the impact of diet on the comparative analyses of microbial metabolites. Caecal samples of hares and rabbits were incubated in triplicate, i.e. without any supplementary substrate (control) or with the addition of wheat bran or oat bran. Calculated as percentage of body weight, the stomachs of the rabbits were heavier than those of the hares, but caeca of the hares weighed more than those of the rabbits. The total SCFA concentration in caecal samples was higher in rabbits than in hares, and it increased in both species when the supplementary fermentation substrates were added. In hares, the molar proportion of propionate was higher and that of butyrate was lower compared to rabbits. The addition of substrate decreased acetate and propionate but increased the molar proportion of butyrate. Microbial fermentation resulted in greater gas release in rabbit caecal samples compared to those of hares. Methanogenesis tended to be lower in hares than in rabbits, but high individual variability was observed, especially in hares. Our study stated lower microbial activity in the caeca of brown hares compared to domestic rabbits. The presented results might lead to assumption that differences between fermentation patterns were not caused by diet but resulted from the peculiarities of both species.  相似文献   

2.
Dirofilaria scapiceps was found between the synovial sheath and tendons, i.e., within the tendon sheath, in the ankle region of eastern cottontail rabbits (Sylvilagus floridanus) and snowshoe hares (Lepus americanus). In cottontail rabbits, tendons and sheaths appeared normal and all worms were adults. Only one (4%) of 24 infected rabbits contained dead worms. All female worms were gravid in rabbits killed in late winter or early spring. Microfilaremias in rabbits were high (approximately 30-100 microfilariae/60 microliter blood) and of long duration (at least 8-28 mo), and rabbits were considered normal hosts of D. scapiceps. In some snowshoe hares, tendons and sheaths also appeared normal; however, in other hares a chronic proliferative tenosynovitis, characterized by fibrinous exudate, hyperplasia and hypertrophy of the intima and inflammatory cell (predominantly lymphocytes and plasma cells) infiltration of the intimal and fibrous layers of the synovial sheath led to encapsulation of worms. Dead subadult, dead adult, and live adult worms were found in the ankles of hares; 86 (46%) of 186 infected hares contained some or only dead worms. Fibrosis commonly occurred around dead worms. Dead subadults were also found in subcutaneous connective tissues over the trunk of the body. Degenerate embryos and amorphous material were observed in uteri of some female worms in hares killed in late winter or early spring. Few (1-5 microfilariae/60 microliter blood) or no microfilariae were observed in the peripheral blood of hares and microfilaremias were of short duration (less than 8 mo). Microfilariae in hares are probably trapped and destroyed in the chronic inflammatory lesions in the tendon sheaths since normal, degenerate, and calcified microfilariae were observed in the capsules around adult worms. Some microfilariae might also be destroyed in lymph nodes. Although D. scapiceps can be maintained within snowshoe hare populations, hares are considered abnormal hosts of D. scapiceps. Dirofilaria scapiceps may have spread from cottontail rabbits to snowshoe hares relatively recently.  相似文献   

3.
Small dermal tumors were found on three African hares (Lepus capensis) in the Laikipia District, Kenya. Gross and histopathologic studies revealed similarities to the Shope's fibroma of wild rabbits in North America and fibromas of European hares. Histological examination of the African hare fibromas revealed intracytoplasmic inclusion bodies characteristic of poxviruses and poxvirus virions were demonstrated by electron microscopy of ultrathin sections. Attempts to propagate the virus in rabbit skin, embryonated chicken eggs and cell cultures were unsuccessful.  相似文献   

4.
Abstract. Most of the data on oral infection of ticks by louping ill virus have been obtained from experiments in which animals were infected by syringe inoculation with infectious material. Using infected ticks to mimic the natural situation, we have demonstrated that louping ill (LI) virus transmission can occur from infected to uninfected Ixodes acinus feeding in close proximity on mountain hares (Lepus timidus). Under these conditions the hares developed either low or undetectable viraemias. Highest prevalence of LI virus infection was observed in recipient nymphs which had fed to repletion between days 3 and 7 post-attachment of virus-infected adults; following engorgement, 56% of nymphs acquired virus. These results demonstrate the efficient transmission of LI virus between co-feeding ticks on naive mountain hares. However, when ticks were allowed to co-feed on virus-immune hares a significant reduction in the frequency of infection was observed. Neither red deer (Cervus elaphus) nor New Zealand White rabbits supported transmission of LI virus. The significance of virus transmission between cofeeding ticks on LI virus epidemiology is discussed.  相似文献   

5.
通过检测塔里木兔(Lepus yarcandensis)胰腺中水通道蛋白(aquaporin,AQP)1和4的表达和分布情况,以探讨水通道蛋白在塔里木兔适应干旱缺水环境中的作用,采用常规 H.E.染色观察塔里木兔胰腺组织学结构,采用免疫组织化学检测AQP1和AQP4在胰腺中的分布位置及表达,并与家兔进行比较。结果显示,AQP1在微血管内皮细胞,血细胞,泡心细胞和小叶内导管上皮细胞均有表达;AQP4在小叶间导管基底膜和胰岛细胞膜上有表达。与家兔相比,AQP1 在塔里木兔胰腺外分泌部的表达较弱,而在小叶内导管的表达较强;AQP4在塔里木兔胰腺内分泌部的表达较低。以上结果说明,AQP1在塔里木兔胰腺小叶内导管的表达上调,推测可能加强了浓缩胰液的能力,以尽量保住体内的水分,是塔里木兔对干旱缺水环境的适应性调节。与家兔相比,塔里木兔胰腺AQP1和AQP4的表达均较低,说明塔里木兔胰腺水液代谢能力比家兔低,这可能与塔里木兔所食食物营养匮乏有关。  相似文献   

6.
通过检测塔里木兔(Lepus yarcandensis)胰腺中水通道蛋白(aquaporin,AQP)1和4的表达及分布情况,以探讨水通道蛋白在塔里木兔适应干旱缺水环境中的作用。采用常规 H.E染色观察塔里木兔胰腺组织学结构,采用免疫组织化学法检测AQP1和AQP4在胰腺中的分布位置及表达,并与家兔(Oryctolagus curiculus)进行比较。结果显示,AQP1在胰腺微血管内皮细胞、血细胞、泡心细胞和小叶内导管上皮细胞均有表达;AQP4在小叶间导管基底膜和胰岛细胞膜上有表达。与家兔相比,AQP1 在塔里木兔胰腺外分泌部的表达较弱,而在小叶内导管的表达较强;AQP4在塔里木兔胰腺内分泌部的表达较低。以上结果说明,AQP1在塔里木兔胰腺小叶内导管的表达上调,推测可能加强了浓缩胰液的能力,以尽量保住体内的水分,这是塔里木兔对干旱缺水环境的适应性调节。与家兔相比,塔里木兔胰腺AQP1和AQP4的表达均较低,说明塔里木兔胰腺水液代谢能力比家兔低,这可能与塔里木兔所食食物营养匮乏有关。  相似文献   

7.
Creation of a VX2 tumor model has traditionally required a laparotomy and surgical implantation of tumor fragments. Open surgical procedures are invasive and require long procedure times and recovery that can result in post-operative morbidity and mortality. The purpose of this study is to report the results of a percutaneous ultrasound guided method for creation of a VX2 model in rabbit livers. A total of 27 New Zealand white rabbits underwent a percutaneous ultrasound guided approach, where a VX2 tumor fragment was implanted in the liver. Magnetic resonance imaging was used to assess for tumor growth and necropsy was performed to determine rates of tract seeding and metastatic disease. Ultrasound guided tumor implantation was successful in all 27 rabbits. One rabbit died 2 days following the implantation procedure. Two rabbits had no tumors seen on follow-up imaging. Therefore, tumor development was seen in 24/26 (92%) rabbits. During the follow-up period, tract seeding was seen in 8% of rabbits and 38% had extra-hepatic metastatic disease. Therefore, percutaneous ultrasound guided tumor implantation safely provides reliable tumor growth for establishing hepatic VX2 tumors in a rabbit model with decreased rates of tract seeding, compared to previously reported methods.  相似文献   

8.
Wild lagomorphs and woodchucks collected predominantly in southern Ontario, Canada were examined for subspecies of Obeliscoides cuniculi (Graybill). Obeliscoides cuniculi multistriatus was found in snowshoe hares (Lepus americanus). Obeliscoides cuniculi cuniculi was found in cottontail rabbits (Sylvilagus floridanus), European hares (Lepus capensis) and woodchucks (Marmota monax). Prevalence of Obeliscoides cuniculi multistriatus in snowshoe hares was 100% and mean intensity (and range of intensity) was 760 (9-4, 198) in Lindsay, Ontario in 1980. Mean intensity in hares varied trimonthly. The highest mean intensity of worms occurred in spring when most worms were adult. Transmission occurred mainly in spring. Most worms present in fall (70%) and winter (54%) were fourth stage. Immature fifth-stage and gravid females were present in hares during fall and winter. Prevalence and mean intensity of O. c. cuniculi in cottontails was 15% and 29 (1-118). Prevalence and mean intensity of O. c. cuniculi in woodchucks was 6% and 56 (16-118). European hares were infected with O. c. cuniculi, prevalence was 10% and mean intensity was 60 (36-83). In Ontario woodchucks and European hares were common in areas frequented by cottontail rabbits and probably acquired sporadic infections of O. c. cuniculi from infected cottontails.  相似文献   

9.
A serologic survey for the agents of Rocky Mountain spotted fever (RMSF) (Rickettsia rickettsii), Borrelia spp. including the causative agent for Lyme disease (Borrelia burgdorferi), and plague (Yersinia pestis) was conducted on blood samples collected from 30 and 46 black-tailed jack rabbits (Lepus californicus) from an urban environment in Lubbock, Texas (USA) during winter 1987 and the following spring 1988, respectively. Antibody titers to the agents of RMSF and borreliosis were detected in sera of 28 and 1% of the jack rabbits, respectively. Neither organisms (rickettsiae and/or spirochetes) nor their associated antigens were detected in any of the tissue or whole blood samples; plague antibodies were not detected in the 76 jack rabbits sampled. Four of 18 ticks (Dermacentor parumapertus) removed from 12 jack rabbits were positive for RMSF using the fluorescent antibody test. The black-tailed jack rabbit is a common wildlife species living in close proximity to higher density human populations in many areas of the southwestern United States. Our results indicate the potential importance of urban populations of this mammal as reservoirs for at least one important zoonotic disease, RMSF, in western Texas.  相似文献   

10.
Coyotes (Canis latrans) from southern Texas were sampled for antibodies to Borrelia burgdorferi from 1980 to 1986; black-tailed jack rabbits (Lepus californicus) and desert cottontails (Sylvilagus audubonii) were sampled in 1986. Coyote fetuses, adult coyote kidneys, and black-tailed jack rabbit and desert cottontail kidneys were cultured for B. burgdorferi in 1986. Results of indirect immunofluorescent antibody (IFA) tests for B. burgdorferi in coyotes were as follows (number positive at a dilution of greater than or equal to 1:128/number tested): 1980 (0 of 30), 1981 (0 of 21), 1982 (0 of 53), 1983 (0 of 78), 1984 (47 of 97), 1985 (20 of 88), and 1986 (42 of 80). Eight of 26 black-tailed jack rabbits and two of seven desert cottontails tested in 1986 had IFA titers to B. burgdorferi of greater than or equal to 1:128. Borrelia burgdorferi was isolated from one of five coyote fetuses, three of 31 adult coyote kidneys, and two of 10 black-tailed jack rabbit kidneys in 1986. These results indicate that B. burgdorferi infection has been present in coyotes in Texas, at least since 1984 and that transplacental transmission occurs.  相似文献   

11.
Weather conditions can have a significant influence on short-term fluctuations of animal populations. In our study, which is based on time series of hunting bag records of up to 28?years from 26 counties of The Netherlands and Germany, we investigated the impact of different weather variables on annual counts of European rabbits (Oryctolagus cuniculus) and European hares (Lepus europaeus). Overall, the long-term dynamics of both species could be described by higher-order polynomials. On a smaller time scale, the number of European hares shot was lower in years with higher amounts of precipitation during late summer/autumn, and the number of European rabbits shot was lower in years with high precipitation in spring of the respective year. We suggest that rainy weather conditions might have lowered the survival of young rabbits in spring and might have generally facilitated the outbreak or spread of diseases in rabbits as well as in hares, specifically in autumn. In addition, the results showed a time-delayed, interactive effect between precipitation in spring and winter weather on European rabbit dynamics: rabbit numbers were limited by low temperatures of the prior winter season, but only when precipitation was high during spring of the previous year. The latter result might be explained by the lowering effects of rainy spring weather on the body condition of the animals, leading to higher sensitivity to harsh winter conditions. In conclusion, our study provides evidence for the impact of weather conditions on the population dynamics of both study species and particularly highlights complex interactions between the prevailing weather conditions during different seasons in the European rabbit.  相似文献   

12.
Ruminants are the principal host for infection by Mycobacterium avium subsp. paratuberculosis (Map), the cause of Johne's disease. Based on studies of a Map-infected population of European rabbits (Oryctolagus cuniculus) in Scotland, lagomorphs as a broad taxonomic order were proposed as potential nonruminant reservoirs for Map. To determine whether a different lagomorph species may serve as a wildlife reservoir, we investigated Map infection in European hares (Lepus europaeus) sharing habitat with known Map-infected dairy cattle in southern Chile. Fecal, mesenteric lymph node, and ileal samples were aseptically collected from 385 wild hares for liquid culture and real-time polymerase chain reaction identification of acid-fast isolates. All tissue samples were also acid-fast stained and examined microscopically. We isolated Map from at least one tissue from 48 hares (12.6%) and fecal samples from 16 hares (4.2%). No Map was found in tissues of eight of the fecal-culture-positive hares. Histologically, all tissues from all hares were within normal limits, and no acid-fast organisms were observed in any sample. Active infection, implying amplification of the organism secondary to resultant disease, was not evident. With this report Map isolations on a population versus incidental detection have now been made from two lagomorph species. However, although the rabbit population studied in Scotland appears to function as a Map reservoir, the hares studied in Chile appear to be a dead-end host, serving only as potential mechanical vectors for the organism.  相似文献   

13.
Prostate cancers show a slow progression from a local lesion (primary tumor) to a metastatic and hormone-resistant phenotype. After an initial step of hyperplasia, in a high percentage of cases a neoplastic transformation event occurs that, less frequently, is followed by epithelial to mesenchymal transition and invasion of healthy tissues (usually bones). MicroRNA-203 (miR-203) is a tumor suppressor microRNA often silenced in different malignancies. Here, we show that miR-203 is downregulated in clinical primary prostatic tumors compared to normal prostate tissue, and in metastatic prostate cancer cell lines compared to normal epithelial prostatic cells. Overexpression of miR-203 in brain or bone metastatic prostate cell lines (DU145 and PC3) is sufficient to induce a mesenchymal to epithelial transition with inhibition of cell proliferation, migration and invasiveness. We have identified CKAP2, LASP1, BIRC5, WASF1, ASAP1 and RUNX2 as new miR-203 direct target mRNAs involved in these events. Therefore, miR-203 could be a potentially new prognostic marker and therapeutic target in metastatic prostate cancer.  相似文献   

14.
Performance and mortality of hares were evaluated for 2 consecutive years in a large farm in Veneto Region (Northern Italy). On average, fertile reproductive pairs (n=318) gave birth 4.8 times and produced 11.4 live leverets, weaned 8.4 leverets and produced 7.0 growing hares (60 days) every year. Mean mortality was 3.6%, 22.9%, 9.7% and 2.5% in newborn (0 to 2 days of age), suckling (3 to 25 days), growing (26 to 60 days) and sub-adult (61 days until sale) hares, respectively. The main causes of mortality were enteric diseases (75.5%, 75.9% and 12.1% in suckling, growing and sub-adult hares, respectively), followed by respiratory diseases (3.4%, 8.0% and 36.2% in suckling, growing and sub-adult hares, respectively), starvation (11.3% and 8.8% in suckling and growing hares, respectively) and trauma (7.1%, 2.3% and 30.2% in suckling, growing and sub-adult hares, respectively). In reproducing hares, mortality was 24.7% and 15.4% in 2010 and 2011, respectively. Respiratory diseases (34.8%) and ulcerative pododermatitis (18.9%) were the most common pathological changes detected in reproducing hares. Farmed hares seem to be affected by diseases resembling those of rabbits reared under intensive conditions. It seems necessary to improve the husbandry of hares to reach satisfactory technical standards and to preserve their health.  相似文献   

15.
《Translational oncology》2020,13(6):100773
Epithelial-mesenchymal transitions (EMTs), the acquisition of mesenchymal features from epithelial cells, occur during some biological processes and are classified into three types: the first type occurs during embryonic development, the second type is associated with adult tissue regeneration, and the third type occurs in cancer progression. EMT occurring during embryonic development in gastrulation, renal development, and the origin and fate of the neural crest is a highly regulated process, while EMT occurring during tumor progression is highly deregulated. EMT allows the solid tumors to become more malignant, increasing their invasiveness and metastatic activity. Secondary tumors frequently maintain the typical histologic characteristics of the primary tumor. These histologic features connecting the secondary metastatic tumors to the primary is due to a process called mesenchymal-epithelial transition (MET). MET has been demonstrated in different mesenchymal tumors and is the expression of the reversibility of EMT. EMT modulation could constitute an approach to avoid metastasis. Some of the targeted small molecules utilized as antiproliferative agents have revealed to inhibit EMT initiation or maintenance because EMT is regulated through signaling pathways for which these molecules have been designed.  相似文献   

16.
BACKGROUND: Epithelioid angiosarcoma (EAS) is a mesenchymal neoplasm that may appear indistinguishable from carcinoma, melanoma and other tumors with epithelioid/epithelial differentiation. We report a case of metastatic postradiation EAS to the lungs that was mistaken for adenocarcinoma. CASE: A 45-year-old woman who received radiotherapy for ductal carcinoma in situ (DCIS) 5 years previously had a local recurrence a year earlier and recent development of bilateral small pulmonary nodules. Fine needle aspiration biopsy of the lung lesions showed round to oval tumor cells with amphophilic cytoplasm. An interpretation of adenocarcinoma was rendered during assessment for specimen adequacy. The original breast tumor was typical of cribriform DCIS. Review of the recurrent breast tumor (initially reported as DCIS) and a prior wedge resection of the lung nodules (reported as EAS) showed an epithelial-appearing tumor exhibiting an endothelial immunophenotype CONCLUSION: The cytologic features of EAS may resemble those of other neoplasms. In evaluating tumors with epithelioid morphology, mesenchymal tumors should also be considered so that appropriate antibodies can be included in the panel for immunohistochemistry. The importance of reviewing the patient's previous biopsy materials cannot be overemphasized.  相似文献   

17.
During cancer progression, malignant cells undergo epithelial-mesenchymal transitions (EMT) and mesenchymal-epithelial transitions (MET) as part of a broad invasion and metastasis program. We previously observed MET events among lung metastases in a preclinical model of prostate adenocarcinoma that suggested a relationship between epithelial plasticity and metastatic spread. We thus sought to translate these findings into clinical evidence by examining the existence of EMT in circulating tumor cells (CTC) from patients with progressive metastatic solid tumors, with a focus on men with castration-resistant prostate cancer (CRPC) and women with metastatic breast cancer. We showed that the majority (> 80%) of these CTCs in patients with metastatic CRPC coexpress epithelial proteins such as epithelial cell adhesion molecule (EpCAM), cytokeratins (CK), and E-cadherin, with mesenchymal proteins including vimentin, N-cadherin and O-cadherin, and the stem cell marker CD133. Equally, we found that more than 75% of CTCs from women with metastatic breast cancer coexpress CK, vimentin, and N-cadherin. The existence and high frequency of these CTCs coexpressing epithelial, mesenchymal, and stem cell markers in patients with progressive metastases has important implications for the application and interpretation of approved methods to detect CTCs.  相似文献   

18.
A captive adult male white-tailed deer (Odocoileus virginianus) with wasting and neurologic signs similar to chronic wasting disease (CWD) was evaluated by histopathology, histochemistry, and immunohistochemistry (IHC) for disease-associated prion protein (PrP(d)). On histologic examination, the brainstem had areas of vacuolation in neuropil and extensive multifocal mineralization of blood vessels with occasional occlusion of the lumen. Some of the clinical and pathologic features of this case were similar to the CWD of white-tailed deer. However, the tissues were negative for PrP(d) by IHC. Because the lesions were more prominent in the obex region of the brainstem, it is speculated that this would have resulted in clinical signs similar to CWD in white-tailed deer. To our knowledge, neither cerebrovascular mineralization nor clinicopathologic changes resembling CWD have previously been described in white-tailed deer without the presence of PrP(d). Such a case should be considered in a differential diagnosis of CWD of white-tailed deer.  相似文献   

19.
From June 1993 through June 1996, 2,260 adult, 4,426 nymphal, and 2,178 larval lone star ticks Amblyomma americanum (L.) were collected in Missouri from vertebrate hosts and by dragging a cloth over vegetation. Prevalence, mean intensity, and relative abundance of each stage varied among hosts. The relative abundance of adult lone star ticks was highest on white-tailed deer, but this stage was also collected from raccoons, opossum, red fox, coyotes, and wild turkey. Nymphs were collected from gray squirrels, eastern cottontail rabbits, opossums, red fox, Carolina wren, and bobwhite quail, but the highest relative abundance occurred on wild turkey, white-tailed deer, and raccoons. Eastern cottontail rabbits, white-tailed deer, raccoons, and squirrels had the highest relative abundance of larval lone star ticks, but they were also found on opossums and wild turkey. The activity of adult lone star ticks was greatest from May through July. The activity for nymphs was highest from May through August, and for larvae, July through September.  相似文献   

20.
Mountain hares were collected each month between April 1984 and March 1985 and their intestines examined for helminths. 26 rabbits were also collected between July and December 1984 and examined for gastro-intestinal helminths. Three nematode and two cestode species were found in the hares while only two nematode and one cestode species were found in the rabbits. Trichostrongylus retortaeformis was recorded from 88% of the 193 hares and 92% of the rabbits while comparable figures for Passalurus ambiguus were 0.5% and 54% and for Mosgovoyia pectinata 14% and 81%. Seasonal fluctuations were observed in the T. retortaeformis populations in the hare; numbers tended to be low during the winter months and high throughout the summer. Paranoplocephala wimerosa was reported for the first time from the British Isles and Trichostrongylus axei was recorded for the first time in the mountain hare.  相似文献   

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