澳大利亚的杜鹃及其寄生适应性(英文)     

Naomi E.LANGMORE 《中国鸟类》2013,4(1):86-92

长期以来,人们一直对寄生性繁殖的杜鹃所采用的种种计谋惊叹不已。本文对澳大利亚的寄生杜鹃如何增加寄生巢的可获得性、如何寻找和接近巢以及如何让宿主接受它们的寄生卵与雏鸟进行了综述。这些杜鹃所采用的对策,有一些是世界上其他杜鹃种类也采用的,但有一些对策,如产隐蔽的卵和模拟的雏鸟,却似乎仅见于澳大利亚的杜鹃。泛性寄生的杜鹃因为要应对较多种类的宿主,难度自然远大于专一性寄生的杜鹃种类,这同时也解释了为什么不同种类的杜鹃进化出不同的寄生策略,以避免不同宿主的识别。  相似文献   

Cardiovascular Effects of Dobutamine and Phenylephrine Infusion in Sevoflurane-anesthetized Thoroughbred Horses     

Minoru OHTA  Shinjiro KURIMOTO  Yuhiro ISHIKAWA  Hirotaka TOKUSHIGE  Naomi MAE  Shun-ichi NAGATA  Masayuki MAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2013,75(11):1443-1448

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Quantitative risk assessment for the annual risk of exposure to Trichinella spiralis in imported chilled pork meat from New Zealand to Singapore     

EKB Richardson  N Cogger  WE Pomroy  MA Potter  RS Morris 《New Zealand veterinary journal》2013,61(5):269-277

Abstract

AIMS: To determine the annual likelihood of exposure to an infectious dose of Trichinella spiralis from consuming imported pork meat from New Zealand to Singapore.

METHODS: Input values specific for chilled pork meat imported into Singapore from New Zealand were used in a quantitative risk-assessment model. The model, designed to allow any combination of importing and exporting countries, was divided into two components, viz the release assessment, and the exposure assessment that assessed the annual risk of exposure to the consumer (ARC). The former estimated the likelihood that a contaminated fresh meat product from New Zealand would arrive at Singapore's border, and took into consideration the prevalence of disease on different types of farms. The latter determined the likelihood over a year that a person in Singapore would consume one or more servings of imported fresh meat from New Zealand that contained a burden of greater than or equal to one larva(e) of T. spiralis per gram after preparation for consumption.

RESULTS: The ARC for offal was 2.41 × 10^?7, which was below the pre-selected safety threshold of 1.00 × 10^?6. The ARC for lean meat was 2.39 x 10^?5, which was above the acceptable safety threshold.

CONCLUSIONS: The study demonstrated that continued routine testing at slaughter is unnecessary for pig offal produced commercially, and provided a model with which to further assess management of the risk of exposure to T. spiralis in lean meat.

CLINICAL RELEVANCE: The potential of Trichinella species to cause disease in humans is a public health concern, and has created adverse effects on the international trade of fresh lean meat without regard to the surveillance measures employed by particular pork-producing countries.  相似文献   

Vitrification procedure decreases inositol 1,4,5‐trisphophate receptor expression,resulting in low fertility of pig oocytes     

Masahiko Hirose  Maki Kamoshita  Katsuyoshi Fujiwara  Tsubasa Kato  Ayaka Nakamura  Richard J. H. Wojcikiewicz  Jan B. Parys  Junya Ito  Naomi Kashiwazaki 《Animal Science Journal》2013,84(10):693-701

Although cryopreservation of mammalian oocytes is an important technology, it is well known that unfertilized oocytes, especially in pigs, are highly sensitive to low temperature and that cryopreserved oocytes show low fertility and developmental ability. The aim of the present study was to clarify why porcine in vitro matured (IVM) oocytes at the metaphase II (MII) stage showed low fertility and developmental ability after vitrification. In vitro matured cumulus oocyte complexes (COCs) were vitrified with Cryotop and then evaluated for fertility through in vitro fertilization (IVF). Although sperm‐penetrated oocytes were observed to some extent (30–40%), the rate of pronuclear formation was low (9%) and none of them progressed to the two‐cell stage. The results suggest that activation ability of cryopreserved oocytes was decreased by vitrification. We examined the localization and expression level of the type 1 inositol 1,4,5 trisphosphate receptor (IP₃R1), the channel responsible for Ca²⁺ release during IVF in porcine oocytes. Localization of IP₃R1 close to the plasma membrane and total expression level of IP₃R1 protein were both decreased by vitrification. In conclusion, our present study indicates that vitrified‐warmed porcine COCs showed a high survival rate but low fertility after IVF. This low fertility seems to be due to the decrease in IP₃R1 by the vitrification procedure.  相似文献   

Post harvest treatments to control eggplant deterioration during storage     

Naomi Temkin-Gorodeiski  B. Shapiro  Shoshana Grinberg  Ida Rosenberger  E. Fallik 《The Journal of Horticultural Science and Biotechnology》2013,88(5):689-693

Eggplant (Solatium melongena L.) fruits deteriorate rapidly during prolonged storage, mainly due to accelerated senescence of the calyx. Dipping the calyx in a solution containing 200 ppm NAA and 900 ppm prochloraz (active ingredient) retarded calyx senescence and controlled decay. At the end of the growing season in Israel (March-May), dipping the whole fruit in the above solution gave better results than dipping the calyx only. After 14 d of storage at 12°C and 3 d at 20°C, the calyx appeared fresh and green and the fruit was firm. Decay incidence did not exceed 5%. The residual level of prochloraz in fruits that were wholly dipped was less than 0.34 mg 1“'.  相似文献   

The Morphophysiological Responses of Free-Floating Aquatic Macrophytes to a Supra-optimal Supply of Manganese     

Claudineia Lizieri  Kacilda Naomi Kuki  Rosane Aguiar 《Water, air, and soil pollution》2012,223(5):2807-2820

Among the many anthropogenic abiotic stresses, manganese (Mn) toxicity has been recognized for its impact on aquatic ecosystems as well as on the biological components of these ecosystems, including aquatic plants. The objective of this study was to determine the Mn accumulation ability of aquatic macrophytes (Azolla caroliniana, Salvinia minima and Spirodela polyrhiza) and evaluate the morphophysiological responses of the species that gather the highest amount of Mn when exposed to a supra-optimal supply of manganese. The experiments were conducted in the laboratory, and the effects of Mn were evaluated based on plant growth; the concentration of total chlorophyll, carotenoids, and anthocyanins; the enzymatic activity of catalase and peroxidase; and leaf anatomy. All of the studied species accumulated Mn in their tissues. Moreover, it was observed that this accumulation was dependent on the concentration of the metal in solution. S. polyrhiza showed higher concentrations of Mn in its tissues (17.062?mg?g^?1 dry weight (DW)), followed by S. minima (4.283?mg?g^?1 DW) and A. caroliniana (1.341?mg?g^?1 DW). Despite the Mn accumulation in all species, S. polyrhiza was the only one selected for further analyses because of its greater ability to accumulate Mn. The high Mn concentration found in tissues of S. polyrhiza suggests that this species has the potential to sequester and accumulate this metal. However, a sensitive response in the plants exposed to higher Mn concentrations (0.4?mM) was observed. The phytotoxicity effects of this accumulation were responsible for a decrease in the plant growth, a reduction in the pigment content (total chlorophyll, carotenoids, and anthocyanins), a low activity of catalase, and the disarrangement of the leaf aerenchyma.  相似文献   

Evaluation of a semi‐controlled test as a selection tool for frost tolerance in durum wheat (Triticum durum)     

Alisa‐Naomi Sieber  Tobias Würschum  Carl Friedrich Horst Longin 《Plant Breeding》2014,133(4):465-469

Most durum wheat (Triticum durum) varieties possess only low winter hardiness due to their frost susceptibility. In North America and Central Europe, durum wheat is therefore typically sown in spring to circumvent the local winter conditions. However, the yield potential of durum in these regions could be much better exploited if durum varieties with increased frost tolerance were available, which could be sown in autumn. A factor limiting breeding for increased frost tolerance is the variation in the occurrence of frost stress across years. The ‘Weihenstephaner Auswinterungsanlage’ is a semi‐controlled test that exposes the plants to all weather conditions. Snow coverage of the plants, serving as frost protection, is prevented by the movable glass lid of the semi‐controlled test. In this study, different scorings for frost tolerance based on this semi‐controlled test were evaluated and compared with frost tolerance data in the field. Our results illustrate the potential of the ‘Weihenstephaner Auswinterungsanlage’ as an indirect selection tool for frost tolerance in durum breeding programmes, especially when regular frost tolerance data from the field are not available.  相似文献   

Successful blastocyst production by intracytoplasmic injection of sperm after in vitro maturation of follicular oocytes obtained from immature female squirrel monkeys (Saimiri boliviensis)     

Shinichi WATANABE  Megumi MIURA  Hiromi MORITA  Moeka NISHI  Shin-ichi YOKOTA  Shosaku HATTORI  Hiromichi MATSUMOTO  Emiko FUKUI  Ken Takeshi KUSAKABE  Masanori OCHI  Naomi NAKAGATA  Yasuo KISO  Chieko KAI  Midori YOSHIZAWA 《The Journal of reproduction and development》2021,67(4):265

Advanced reproductive technologies are being applied for the propagation of squirrel monkeys, to ensure their preservation as a genetic resource and the effective use of their gametes in the future. In the present study, oocytes and spermatozoa were collected from live squirrel monkeys, following which piezo intracytoplasmic sperm injection (ICSI) was performed using these gametes. Follicular development was induced by administering equine chorionic gonadotropin (eCG) containing inhibin antiserum to an immature squirrel monkey female. The unilateral ovary was excised after the administration of human chorionic gonadotropin (hCG), to induce ovulation, following which the larger developed follicular oocytes were collected. Follicular oocytes were prepared for ICSI using sperm from the epididymal tail of a unilateral testis extracted from a mature male. The embryos were continuously incubated in CMRL 1066 medium supplemented with 10% (v/v) fetal bovine serum. Embryo culture was performed with cumulus cells. Two experiments of ICSI carried out with three females resulted in 14 mature oocytes from the 49 cumulus-oocyte complexes collected and five embryos, three of which developed into blastocysts. These blastocysts were vitrified, thawed, and transferred to recipient monkeys, but no pregnancies resulted. In conclusion, the present study is the first to successfully produce ICSI-derived blastocysts from MII oocytes obtained by means of hormone administration (a combination of eCG+inhibin antiserum and hCG) and in vitro maturation in immature squirrel monkeys.  相似文献   

Impact of kiwifruit bacterial canker on productivity of cv. Hayward kiwifruit using observational data and multivariable analysis          下载免费PDF全文

K. J. Froud  R. M. Beresford  N. C. Cogger 《Plant pathology》2018,67(3):671-681

A virulent strain of Pseudomonas syringae pv. actinidiae biovar 3 (Psa), which causes bacterial canker in kiwifruit, was first recorded in New Zealand in November 2010. This strain has severely affected Actinidia chinensis var. chinensis ‘Hort16A’ kiwifruit productivity but its effect on green Actinidia chinensis var. deliciosa ‘Hayward’ kiwifruit productivity has been variable. An observational study design was used to develop explanatory models to quantify the impacts of Psa infection on productivity (tray equivalents per hectare) of Hayward kiwifruit harvested in 2012, using data captured by industry from 2599 orchards. A total of 934 orchards were Psa positive at the end of the study period. Multivariable linear regression was used to model 2012 productivity in the presence of Psa, while controlling for regional differences, elevation, 2011 productivity, harvest dates and application of agrichemicals. The model showed productivity was initially higher in the presence of Psa, and was not reduced until after 1 year of infection. The relationship between protective spray use and productivity was also quantified. It is likely that improved disease management has offset the impact of the disease and future research should consider a reassessment of the effects of disease after longer term exposure to Psa in New Zealand. The use of an observational cohort study to assess disease impacts using multivariable analysis could have wider application in the field of plant epidemiology.  相似文献   

Technology generation to dissemination: lessons learned from the tef improvement project     

Gina Cannarozzi  Solomon Chanyalew  Kebebew Assefa  Abate Bekele  Regula Blösch  Annett Weichert  Dominik Klauser  Sonia Plaza-Wüthrich  Korinna Esfeld  Moritz Jöst  Abiel Rindisbacher  Habte Jifar  Victoria Johnson-Chadwick  Ermias Abate  Wuyan Wang  Rizqah Kamies  Negussu Husein  Worku Kebede  Kidist Tolosa  Yazachew Genet  Kidu Gebremeskel  Brikti Ferede  Firew Mekbib  Federico Martinelli  Hans Christian Pedersen  Suhail Rafudeen  Shimelis Hussein  Muluneh Tamiru  Naomi Nakayama  Mike Robinson  Ian Barker  Samuel Zeeman  Zerihun Tadele 《Euphytica》2018,214(2):31

Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef—an orphan crop important to the food security in the Horn of Africa, a region of the world with recurring devastating famines. We have established an efficient pipeline to bring improved tef lines from the laboratory to the farmers of Ethiopia. Of critical importance to the long-term success of this project is the cooperation among participants in Ethiopia and Switzerland, including donors, policy makers, research institutions, and farmers. Together, European and African scientists have developed a pipeline using breeding and genomic tools to improve the orphan crop tef and bring new cultivars to the farmers in Ethiopia. We highlight a new variety, Tesfa, developed in this pipeline and possessing a novel and desirable combination of traits. Tesfa’s recent approval for release illustrates the success of the project and marks a milestone as it is the first variety (of many in the pipeline) to be released.  相似文献