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Metlholo Andries Phukuntsi Helene Brettschneider Desiré L Dalton Teresa Kearney Jacqueline Badenhorst Antoinette Kotze 《African Zoology》2016,51(1):69-76
DNA barcoding has been proposed as a method for species identification. However, this method has been criticised for its over-reliance on a single mitochondrial gene. In this study, four mitochondrial gene regions and one nuclear gene region were used to investigate their different abilities to identify tissue associated with museum specimens of Aethomys chrysophilus, Aethomys ineptus and Micaelamys namaquensis. Aethomys chrysophilus and the more recently elevated A. ineptus are indistinguishable on morphological grounds; however, their ranges are largely parapatric with only one syntopic locality currently known. All of the mitochondrial gene regions were able to separate M. namaquensis from A. chrysophilus and A. ineptus, but they varied in their abilities to resolve differences between A. chrysophilus and A. ineptus. The sequence results identified a specimen from KwaZulu-Natal that was misclassified and should have been identified as A. ineptus. Seven specimens that had not been reclassified following the elevation of A. ineptus to species level were identified as A. ineptus. Individuals of A. chrysophilus from Malawi could not be classified as either A. chrysophilus or A. ineptus, and may be a hybrid or a new, distinct species. This study indicates that DNA barcoding may be used to separate M. namaquensis from A. chrysophilus and A. ineptus, and although it was not able to separate A. chrysophilus and A. ineptus, it did indicate specimens from Malawi may be a new cryptic species. 相似文献
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Suwannachot P Joosten BJ Klarenbeek A Hofma J Enzerink E van Weeren PR Everts ME 《American journal of veterinary research》2005,66(7):1252-1258
OBJECTIVE: To investigate the effects of moderate short-term training on K+ regulation in plasma and erythrocytes during exercise and on skeletal muscle Na+,K(+)-ATPase concentration in young adult and middle-aged horses. ANIMALS: Four 4- to 6-year-old and four 10- to 16-year-old Dutch Warmblood horses. PROCEDURE: The horses underwent a 6-minute exercise trial before and after 12 days of training. Skeletal muscle Na+,K(+)-ATPase concentration was analyzed in gluteus medius and semitendinosus muscle specimens before and after the 12-day training period. Blood samples were collected before and immediately after the trials and at 3, 5, 7, and 10 minutes after cessation of exercise for assessment of several hematologic variables and analysis of plasma and whole-blood K+ concentrations. RESULTS: After training, Na+,K(+)-ATPase concentration in the gluteus medius, but not semitendinosus, muscle of middle-aged horses increased (32%), compared with pretraining values; this did not affect the degree of hyperkalemia that developed during exercise. The development of hyperkalemia during exercise in young adult horses was blunted (albeit not significantly) without any change in the concentration of Na+,K(+)-ATPase in either of the muscles. After training, the erythrocyte K+ concentration increased (7% to 10%) significantly in both groups of horses but did not change during the exercise trials. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, the activation of skeletal muscle Na+,K(+)-ATPase during exercise is likely to decrease with age. Training appears to result in an increase in Na+,K(+)-ATPase activity in skeletal muscle with subsequent upregulation of Na+,K(+)-ATPase concentration if the existing Na+,K(+)-ATPase capacity cannot meet requirements. 相似文献
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van Foreest A 《Tijdschrift voor diergeneeskunde》2004,129(18):593-595
The distal roots of the mandibular molars (309 & 409) are often exposed in cats with chronic, recurrent inflammation of the oral mucous membranes. The disorder can be easily detected during a thorough investigation under light sedation. Some reasons are given why the diagnostic investigation is sometimes performed incompletely. 相似文献
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Andries A. Temme Kelly L. Kerr Lisa A. Donovan 《Journal of Agronomy and Crop Science》2019,205(5):508-518
Developing more stress‐tolerant crops will require greater knowledge of the physiological basis of stress tolerance. Here, we explore how biomass declines in response to salinity relate to leaf traits across 20 genotypes of cultivated sunflower (Helianthus annuus). Plant growth, leaf physiological traits and leaf elemental composition were assessed after 21 days of salinity treatments (0, 50, 100, 150 or 200 mM NaCl) in a greenhouse study. There was a trade‐off in performance such that vigorous genotypes, those with higher biomass at 0 mM NaCl, had both a larger absolute decrease and proportional decrease in biomass due to increased salinity. More vigorous genotypes at control were less tolerant to salinity. Contrary to expectation, genotypes with a low increase in leaf Na and decrease in K:Na were not better at maintaining biomass with increasing salinity. Rather, genotypes with a greater reduction in leaf S and K content were better at maintaining biomass at increased salinity. While we found an overall trade‐off between sunflower vigour and salt tolerance, some genotypes were more tolerant than expected. Further analysis of the traits and mechanisms underlying this trade‐off may allow us to breed these into high‐vigour genotypes in order to increase their salt tolerance. 相似文献
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van Foreest A 《Tijdschrift voor diergeneeskunde》2011,136(1):30-35
The treatment of dental problems in animals and humans requires a different approach. While a basic knowledge of medicine is sufficient for dentists, a degree in veterinary medicine is a prerequisite for performing dental procedures in animals. Concepts such as oral-health veterinarian and dental care technician will be part of animal dental care in the future. When deciding on the plan of treatment, veterinarians should pay attention to the symptomatology, oral examination, and pain response. A number of treatments that are self-evident in human dentistry are often not recommended in veterinary medicine. Dental treatments for companion animals should be characterized by minimal interventions with maximum results: effective, efficient, and most of all patient/client focused. 相似文献
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Summary Methods were developed for clean-up of potato tuber extracts on solid phase extraction CN-cartridges and for analysis of steroidal
glycoalkaloids by reversed phase HPLC. The alkaloids α-solanine, α-chaconine, α-solasonine and α-solamargine could be separated
on C8 or C18 reversed phase columns using a mobile phase of acetonitrile/Tris-buffer (3∶2, v/v). The analysis time of tuber extracts containing
these alkaloids was less then 4 min, if the pH of the mobile phase was adjusted to 7.4 and run at a flow rate of 0.5 ml/min. 相似文献