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Retracted: Effect of Post‐Thaw Storage Time on Motility and Fertility of Cryopreserved Beluga Sturgeon (Huso huso) Sperm
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The aim of this study was to test the influence of post ‐ thaw storage time on the duration of sperm motility, percentage of motile sperm, and fertilization and hatching rates of fresh sperm and sperm stored for 0, 30 and 60 min at 4°C post‐thawing. After being frozen in liquid nitrogen and then thawed, the percentage of motile sperm and duration of motility were not affected by 30 min of storage at 4°C, whereas a significant decline in these parameters was observed after 60 min of storage. Similarly, fertilization and hatching rates were significantly affected within 60 min of storage at 4°C, and the fertility of frozen‐thawed sperm was significantly lower than that of fresh sperm. We conclude that cryopreserved sperm of beluga sturgeon could be stored for 30 min without the loss of sperm quality. This described procedure for beluga sturgeon cryopreservation is reliable and efficient and therefore can be recommended for hatchery practice after scaling up this technique. 相似文献
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Two cases of Rhodococcus equl infection in foals are described, in which osteomyelitis was a feature. Because rhodococcal infection is usually low grade and chronic, and because the signs of early metaphysitis can be subtle, any articular or periarticular swelling in a foal from a farm with a history of rhodococcosis should be strongly suspected to be associated with R equl until proven otherwise. 相似文献
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Antonio Evidente Rossitza Rodeva Anna Andolfi Zornitsa Stoyanova Carmen Perrone Andrea Motta 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(2):173-182
Recently, a new fungal disease caused by Diaporthe angelicae (anamorph Phomopsis foeniculi) has been found with increasingly frequency on fennel (Foeniculum vulgare) in Bulgaria. Using a bioassay-guided isolation and purification procedure, different metabolites were isolated from the
fungal culture filtrates. They were identified by spectroscopic methods as nectriapyrone, a pentaketide monoterpenoid, and
altersolanols A and J and macrosporin, three octaketides anthracenones. Leaf puncture bioassay was applied on detached tomato
leaves to prove the phytotoxic activity of the fractions and of pure compounds. Nectriapyrone and altersolanols A and J showed
a modulated phytotoxicity, while macrosporin was not toxic. Altersolanol A was the most active compound. 相似文献
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Gap disturbances and regeneration patterns in a Bosnian old-growth forest: a multispectral remote sensing and ground-based approach 总被引:1,自引:0,他引:1
Matteo Garbarino Enrico Borgogno Mondino Emanuele Lingua Thomas A. Nagel Vojislav Duki? Zoran Govedar Renzo Motta 《Annals of Forest Science》2012,69(5):617-625
Objectives
We examined canopy gap structure and regeneration patterns at the landscape scale using a combination of remote sensing and field-based surveys.Methods
The study was carried out in the forest reserve of Lom, an old-growth Fagus-Abies-Picea forest located within the Dinaric Alps in the north-western part of Bosnia and Herzegovina. A high-resolution (1-m panchromatic and 4-m multispectral) Kompsat-2 satellite image was orthorectified and classified through an unsupervised pixel-based classification using an artificial neural network method.Results
This approach allowed the identification of 650 canopy gaps, ranging in size from 32 to 1,776?m2. Only 20 intermediate to large gaps (>250?m2) were identified, and they were mainly present near the perimeter of the reserve. The origin of these large openings was associated with past human-caused disturbances or topographic conditions. The species composition of regeneration within large, human-caused gaps differed markedly from small gaps and non-gap sites in the core area of the reserve. Shade-intolerant species dominated the seedling and sapling layers in large openings. The landscape approach employed in this study confirmed the hypothesis that small gaps predominate at Lom, especially within the core area of the reserve. 相似文献9.
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CASE HISTORY: A mature male tuatara was presented with a history of recurrent cloacal prolapse. CLINICAL AND PATHOLOGICAL FINDINGS: The prolapsed tissue included a 12 mm diameter mass, which histologically showed cords and nodules of neoplastic epithelial cells. DIAGNOSIS: The mass was diagnosed as a squamous cell carcinoma with ulceration of the overlying stratified squamous epithelium and diffuse inflammation of the surrounding dermis. CLINICAL RELEVANCE: This case presented a rare opportunity to investigate squamous cell carcinoma in a long-lived lower vertebrate species. Future recurrence or metastasis of the mass may add useful information to the current base of knowledge of the behaviour of malignant neoplasms in reptiles. 相似文献