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Amblypygi are tropical and subtropical ambush predators that use elongated, raptorial pedipalps for different activities. Although pedipalp use in predation and courtship has been explored in videography in vivo analyses, kinematic ex vivo examination of these appendages has not been conducted. Here, we rectify this lack of data by using micro-CT scans to 3D-kinematically model the appendage morphology and the range of motion (ROM) of the joints for Damon medius and Heterophrynus elaphus. We illustrate the successful application of this technique to terrestrial euarthropods in determining the maximum ROM values for each pedipalp joint. We also note that, in life, these values would be lower due to motion restricting structures like tendons, arthrodial membranes, and muscles. We further compare our maximum values obtained here with data from video-based motion analyses. The ROM of each joint shows the greatest flexibility in the femur-tibia joint (140–150°), the lowest in the basitarsus-claw joint (35–40°). ROM in the tibia-basitarsus joint is markedly distinct (D. medius: 44°; H. elaphus: 105°). This disparity reflects how H. elaphus uses the joint in the capture basket, while D. medius uses the femur-tibia joint to form the capture basket. We further illustrate notable vertical motion of the H. elaphus pedipalp compared to D. medius. This difference reflects the retro-ventral trochanter apophysis of H. elaphus. Our study opens the possibility to further whip spider kinematic understanding. Examination of other taxa using this approach will result in a more comprehensive understanding of the ecological significance and ethological implications of this unique arachnid group. 相似文献
3.
JI Yun HJ Park MH Park MS Kim JH Choi E Lee SP Gong JM Lim ST Lee 《Reproduction in domestic animals》2014,49(5):705-710
Recently, isolation and in vitro culture of putative spermatogonial stem cells (SSCs) in the domestic cat have been conducted. However, the cellular niche conditions that facilitate the establishment and long‐term maintenance of feline SSCs (FSSCs) have not been described. Therefore, we investigated the type of feeder cells used to stimulate colony formation and growth of FSSCs among the various factors in the FSSC niche. Spermatogonial stem cells isolated from feline testes were cultured on mitotically inactivated testicular stromal cells (TSCs) derived from cats, dogs and mice, and mouse embryonic fibroblasts (MEFs). The formation and growth of colonies derived from SSCs cultured on each type of feeder cell were identified at passage 0, and the morphology, alkaline phosphatase (AP) activity and expression of SSC‐specific genes in surviving colonies were investigated at passage 4. Among these diverse feeder cells, TSCs from cat showed the greatest colony formation, growth and maintenance of FSSCs, and SSC colonies cultured by passage 4 showed a typical dome‐shaped morphology, AP activity and expression of SSC‐specific genes (NANOG, OCT4, SOX2 and CD9). Accordingly, these results demonstrate that feline TSCs could be used as feeder cells to support the establishment and maintenance of SSCs from domestic cats. 相似文献
4.
Roger A. BALDWIN Terrell P. SALMON Robert H. SCHMIDT Robert M. TIMM 《Integrative zoology》2014,9(3):265-279
Many wildlife species cause extensive damage to a variety of agricultural commodities in California, with estimates of damage in the hundreds of millions annually. Given the limited availability of resources to solve all human–wildlife conflicts, we should focus management efforts on issues that provide the greatest benefit to agricultural commodities in California. This survey provides quantitative data on research needs to better guide future efforts in developing more effective, practical and appropriate methods for managing these species. We found that ground squirrels, pocket gophers, birds, wild pigs, coyotes and voles were the most common agricultural wildlife pest species in California. The damage caused by these species could be quite high, but varied by agricultural commodity. For most species, common forms of damage included loss of crop production and direct death of the plant, although livestock depredation was the greatest concern for coyotes. Control methods used most frequently and those deemed most effective varied by pest species, although greater advancements in control methods were listed as a top research priority for all species. Collectively, the use of toxicants, biocontrol and trapping were the most preferred methods for control, but this varied by species. In general, integrated pest management practices were used to control wildlife pests, with a special preference for those approaches that were efficacious and quick and inexpensive to apply. This information and survey design should be useful in establishing research and management priorities for wildlife pest species in California and other similar regions. 相似文献
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Distributions of the vector Culicoides brevitarsis Kieffer (Diptera: Ceratopogonidae) (determined from light trap data) and 2 arboviruses (determined from seroconversions in sentinel cattle) were studied in eastern New South Wales in 1993–94. C brevitarsis was recorded progressively from endemic areas on the north coast, to Nowra on the south coast, and westward to Scone, in the Hunter Valley. C brevitarsis also survived through winter at Paterson, in the Hunter Valley. Its apparently focal reappearance in this marginal area had no obvious effect on the broad pattern of its progression or the dispersal of Akabane and bluetongue viruses. These viruses were first recorded from foci near Coffs Harbour, on the mid-north coast. Their first occurrences at different locations were associated with those of C brevitarsis, but not with each other. The viruses were found only within the recorded limits of the vector's distribution. Delays between the initial occurrence of C brevitarsis and first evidence of virus transmissions at locations ranged from 2 to 7 months. The delays decreased away from the points of focus and were negatively associated with the time of initial occurrence of the vector. Seroconversions to the viruses were related to the presence of C brevitarsis. However, the densities of C brevitarsis had no apparent effect on the initial numbers of cattle seroconverting to either virus. The results support the conclusion that the progressions of C brevitarsis and Akabane and bluetongue viruses were the result of gradual movements by the vector. 相似文献
7.
R. M. HANNA R. E. BORCHARD S. L. SCHMIDT 《Journal of veterinary pharmacology and therapeutics》1988,11(2):121-129
Rate constants of elimination were used to evaluate potential effects of diuretic agents on the elimination of ketamine from the blood of cats. Furosemide, mannitol, and aminophylline did not significantly alter the ketamine elimination rate constants, although the diuretics had a tendency to prolong elimination. This tendency of furosemide was further substantiated by observing the effect of furosemide on glomerular filtration. The rate of sulfanilate elimination, used as an indicator of glomerular filtration, was significantly decreased in the cats that were administered furosemide. Possible mechanisms for the influence of furosemide on the renal excretion of ketamine are discussed. 相似文献
8.
R. M. HANNA R. E. BORCHARD S. L. SCHMIDT 《Journal of veterinary pharmacology and therapeutics》1988,11(1):84-93
Ketamine HCl [2-(o-chlorophenyl)-2-(methylamino) cyclohexanone HCl] concentrations in whole blood were used to study the pharmacokinetics of i.v., i.m., and rectal administrations, at a dose of 25 mg/kg, in normal domestic cats. Absorption was rapid with both the i.m. and rectal routes. Systemic availability was 51% (SEM 10) for the i.m. dose and 43.5% (SEM 6.1) for the rectal dose. The first-pass effect had a minimal influence on the metabolism of ketamine HCl administered rectally. The elimination rate constant (beta) of the drug was statistically similar in the i.v., i.m., and rectal groups, at a 95% level of significance (P less than 0.05). At the dosage rates studied, ketamine HCl produced an anesthetic effect in the cat following i.v., i.m. and rectal administration. 相似文献
9.
ROBERT E. SCHMIDT ROBERT M. LETSCHER JOHN D. TOFT II† 《The Journal of small animal practice》1983,24(12):759-762
Disseminated megakaryocytic neoplasia was diagnosed in a 3-year-old cat. Hepatomegaly, splenomegaly, and abnormal platelets in the peripheral blood characterized the condition. Neoplastic megakaryocytes were present in numerous organs. No evidence of feline leukemia virus was found. 相似文献
10.
A tone ending in unavoidable electric shock was periodically presented to pigeons while they pecked a key for food. When pecking was completely disrupted by tone, shock was disconnected, and the training tone and tones having new frequencies were presented. Initially the gradient of generalization was broad; as testing proceeded, however, the gradient narrowed severely. 相似文献