Feasibility of Using Commercial Reagent Test Strips for Estimation of Blood Urea Nitrogen Concentrations in Captive Black-Tailed Prairie Dogs (Cynomys ludovicianus)

The black-tailed prairie dog (Cynomys ludovicianus) is a squirrel-like rodent (Sciuridae) that is used as an animal model for human gallbladder disease, as well as research on several viral and bacterial diseases. Prairie dogs are also prone to develop hepatobiliary diseases that can impair liver function. As a result, monitoring blood urea nitrogen (BUN) concentration or azotemia via low-volume blood samples with immediate test results can be clinically beneficial. In this study, blood samples were collected from captive black-tailed prairie dogs. The BUN analysis was performed in duplicate using a veterinary biochemistry analyzer and commercial reagent test strips. The indication of azotemia by the reagent test strips, when compared to plasma BUN results of prairie dogs with and without confirmed azotemia, had a sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 95%, 71%, and 100%, respectively. Based on the results of this study, the reagent test strips provided a moderately accurate method of estimating the BUN concentration and high accuracy reporting both normal and azotemic black-tailed prairie dogs. Continued investigation into alternative point-of-care testing for prairie dogs is warranted, but standard blood chemistry analyzers should still be considered the most accurate method of BUN testing and azotemia determination for this species.     

不同碳源及浓度对草原樱桃组培苗繁育的影响

为降低草原樱桃组培苗生产的成本,加快组培苗推广,本试验研究了不同碳源对草原樱桃增殖和生根的影响。结果显示,蔗糖和白砂糖为草原樱桃组培快繁的最佳碳源,当浓度为20g·L-1和30g·L-1时,草原樱桃组培苗的繁殖系数和生根均较好,而从经济角度考虑,可用白砂糖代替蔗糖,白砂糖浓度为20g·L-1。     

Genetic transformation of Eustoma grandiflorum Griseb. by microprojectile bombardment

Summary Foreign DNA was introduced into cell suspension cultures and leaf tissue of Eustoma grandiflorum Griseb. (lisianthus) by microprojectile bombardment. For this purpose a low-cost bombardment device that uses a helium flux to accelerate microprojectiles was built. When cell suspensions were used, an average of 4.1 Kan resistant calli were recovered per shot after 4 months' cultivation on selective medium. Most of the Kan resistant plants regenerated from calli were positive to GUS assay. Both the nptII and gus genes were successfully amplified from alkali-treated leaves of putative transgenic plants by PCR analysis. Transgenic plants were not recovered from bombarded leaves. Considering the host range specificity of Agrobacterium, and the response of the species to plant regeneration from suspension culture, microprojectile bombardment is, at present, the most efficient procedure for genetic transformation of lisianthus.Abbreviations BA 6-benzyladenine - Cx cefotaxime - 2,4 D (2,4-dichlorophenoxy) acetic acid - FDA fluorescein diacetate - gus -glucuronidase - IAA indole-3-acetic acid - IBA indole-3-butyric acid - 2iP (2-isopentenyl) adenine - Kan kanamycin - nptII neomycin phosphotransferase II - PCR polymerase chain reaction     

Assessing wind and mammals as seed dispersal vectors in an invasive legume

While some plants have modified seed structures to facilitate dispersal, many lack such specialised adaptations, making their mode of dispersal unclear. This can be particularly problematic for predicting shifts in species ranges or tracking the spread of invasive plants. As an example, the seed size and shape of the invasive legume, Lespedeza cuneata, suggest that wind and attachment to animals are not important for dispersal, yet populations can spread surprising distances within a few years. Using a series of experiments conducted in the laboratory and field, we tested wind and mammal fur as mediators of seed dispersal. To test wind dispersal, seed traps were arranged radially around a patch of L. cuneata and seeds were collected following dispersal. Attachment to mammal fur was tested by fitting pelts of a deer, coyote and raccoon to artificial torsos and determining seed retention in both the field and the laboratory. Laboratory trials also examined the influence of wet versus dry conditions. Our results showed that wind direction strongly influenced dispersal distance and seeds were readily dispersed by mammal fur. The number of seeds retained was species specific, depending on fur depth and mammal size, with seed retention increasing under wet conditions. Together, these results suggest that both wind and mammal fur contribute to the movement of L. cuneata across grasslands. Consequently, both dispersal vectors should be considered when designing and implementing control strategies.     

牧区草地资源利用的三元化结构及其水问题

牧区草原生态的修复,必须对草地资源的利用实施三元化战略,三元化利用的关键是水资源的合理开发利用。脆弱的草原生态系统与水资源的关系致为密切,水资源的开发利用稍有不慎,就会导致草原生态系统的受损,必须以生态学的观点科学合理地配置和利用水资源。     

河北省坝上红松洼草原蝗虫群落结构与多样性调查

为明确不同分区治理下河北省坝上红松洼草原生态环境对蝗虫群落多样性的影响,采用样方法于2019-2020年在不同草原类型和不同功能分区对蝗虫群落进行调查,通过丰富度、个体数、多样性指数以及均匀度指数分析蝗虫的多样性,并对不同生态因子和蝗虫多样性指标进行相关性分析.结果 表明:该地区蝗虫发生种类共有5科8亚科14属25种,...