Epitheliocystis in three wild fish species in Tasmanian waters     

M C Stride  B F Nowak 《Journal of fish diseases》2014,37(2):157-162

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Expression of aquaporin 4 in the chicken ovary in relation to follicle development          下载免费PDF全文

M Nowak  M Grzesiak  N Saito  M Kwaśniewska  A Sechman  A Hrabia 《Reproduction in domestic animals》2017,52(5):857-864

In the mammalian ovary, aquaporins (AQPs) are thought to be involved in the regulation of fluid transport within the follicular wall and antrum formation. Data concerning the AQPs in the avian ovary is very limited. Therefore, the present study was designed to examine whether the AQP4 is present in the chicken ovary, and if so, what is its distribution in the ovarian compartment of the laying hen. Localization of AQP4 in the ovarian follicles at different stage of development was also investigated. After decapitation of hens the stroma with primordial follicles and white (1–4 mm), yellowish (4–8 mm), small yellow and the three largest yellow pre‐ovulatory follicles F3‐F1 (F3 < F2 < F1; 20–36 mm) were isolated from the ovary. The granulosa and theca layers were separated from the pre‐ovulatory follicles. The AQP4 mRNA and protein were detected in all examined ovarian compartments by the real‐time PCR and Western blot analyses, respectively. The relative expression of AQP4 was depended on follicular size and the layer of follicular wall. It was the lowest in the granulosa layer of pre‐ovulatory follicles and the highest in the ovarian stroma as well as white and yellowish follicles. Along with approaching of the largest follicle to ovulation the gradual decrease in AQP4 protein level in the granulosa layer was observed. Immunoreactivity for AQP4 was present in the granulosa and theca cells (theca interna ≥ theca externa > granulosa). The obtained results suggest that AQP4 may take part in the regulation of water transport required for follicle development in the chicken ovary.  相似文献   

Long-term impact of de-icing salts on tree health in the Lake Tahoe Basin: Environmental influences and interactions with insects and diseases     

Isabel A. Munck  Chandalin M. BennettKim S. Camilli  Robert S. Nowak 《Forest Ecology and Management》2010

Lake Tahoe, on the boundary of California and Nevada, is world renown for its natural beauty and is also a popular location for winter-sporting activities. De-icing compounds, such as sodium chloride (NaCl), are used to maintain safe winter driving conditions. Sodium chloride, however, can damage roadside vegetation and affect surface and ground water quality. Our objectives were to: investigate the relationship among salt damage to trees and other damage (from insects, diseases, and other biotic and abiotic factors), examine the effects of vegetation characteristics and environmental factors on salt damage to trees, and to quantify the long-term impacts of de-icing salts on roadside conifers in the Tahoe Basin. From 2006 to 2008, 442 square plots (0.1 ha) were established and surveyed throughout the Lake Tahoe Basin, including 176 control plots > 300 m from roads, and 137 plots originally established in 1990 that were used for long-term trends. Both incidence and severity of salt damage, diseases, insect pests, and other abiotic damage were recorded on all trees within plots (more than 10,000 trees). Soil and vegetation samples were collected from a subset of plots and analyzed for salt content. At least 15% of roadside trees were damaged by salt every year. Very large year-to-year variation in the incidence of salt damage was observed, but the severity of salt damage has decreased since 1990. A clear roadside effect on roadside conifers existed because symptoms of salt damage were only observed on trees in roadside plots and never in control plots, and foliage from trees in roadside plots had more sodium and chloride content than those in control plots for both salt symptomatic and asymptomatic foliage. Incidence of salt damage decreased with increasing distance from roads, was more frequent on rocky soils, and increased with downhill slope steepness and tree density. Pines (Pinus spp.) were more frequently and severely damaged by salt than firs (Abies spp.). Trees were more likely to be damaged by something other than salt, and the relationship among salt damage and other damages was antagonistic rather than synergistic. The results from this study have important implications for the ecology and management of conifer forests in relation to salinity and road maintenance.  相似文献   

Microencapsulation of a putative probiotic Enterobacter species,C6‐6, to protect rainbow trout,Oncorhynchus mykiss (Walbaum), against bacterial coldwater disease          下载免费PDF全文

B Ghosh  K D Cain  B F Nowak  A R Bridle 《Journal of fish diseases》2016,39(1):1-11

Flavobacterium psychrophilum is the causative agent of bacterial coldwater disease (BCWD), which has a major impact on salmonid aquaculture globally. An Enterobacter species, C6‐6, isolated from the gut of rainbow trout, Oncorhynchus mykiss (Walbaum), has been identified as a potential probiotic species providing protection against BCWD. This study examined the effects of alginate microencapsulation on the protective efficacy of C6‐6 against BCWD in vivo when administered to rainbow trout fry orally or by intraperitoneal (IP) injection. Viable C6‐6 bacteria were microencapsulated successfully, and this process (microencapsulation) did not significantly deteriorate its protective properties as compared to the administration of non‐microencapsulated C6‐6 bacteria. Both oral and IP delivery of C6‐6 achieved significantly better protection than control treatments that did not contain C6‐6 bacteria. The highest relative percent survival (RPS) resulted from IP delivery (71.4%) and was significantly greater than the highest oral RPS (38.6%). Successful intestinal colonization was not critical to protective effects of C6‐6. The study showed that C6‐6 administration, with or without encapsulation, was a viable choice for protecting fry from BCWD especially when administered intraperitoneally.  相似文献   

Triblock copolymer syntheses of mesoporous silica with periodic 50 to 300 angstrom pores   总被引：32，自引：0，他引：32  

D Zhao  J Feng  Q Huo  N Melosh  GH Fredrickson  BF Chmelka  GD Stucky 《Science (New York, N.Y.)》1998,279(5350):548-552

Use of amphiphilic triblock copolymers to direct the organization of polymerizing silica species has resulted in the preparation of well-ordered hexagonal mesoporous silica structures (SBA-15) with uniform pore sizes up to approximately 300 angstroms. The SBA-15 materials are synthesized in acidic media to produce highly ordered, two-dimensional hexagonal (space group p6mm) silica-block copolymer mesophases. Calcination at 500 degrees C gives porous structures with unusually large interlattice d spacings of 74.5 to 320 angstroms between the (100) planes, pore sizes from 46 to 300 angstroms, pore volume fractions up to 0.85, and silica wall thicknesses of 31 to 64 angstroms. SBA-15 can be readily prepared over a wide range of uniform pore sizes and pore wall thicknesses at low temperature (35 degrees to 80 degrees C), using a variety of poly(alkylene oxide) triblock copolymers and by the addition of cosolvent organic molecules. The block copolymer species can be recovered for reuse by solvent extraction with ethanol or removed by heating at 140 degrees C for 3 hours, in both cases, yielding a product that is thermally stable in boiling water.  相似文献   

Measuring the spin polarization of a metal with a superconducting point contact     

Soulen Jr RJ  JM Byers  MS Osofsky  B Nadgorny  T Ambrose  SF Cheng  Broussard C T Tanaka PR  J Nowak  JS Moodera  A Barry  JMD Coey 《Science (New York, N.Y.)》1998,282(5386):85-88

A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2.  相似文献   

Effect of extracellular products of Tenacibaculum maritimum in Atlantic salmon, Salmo salar L.     

R van Gelderen  J Carson  B Nowak 《Journal of fish diseases》2009,32(8):727-731

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Host response to the chondracanthid copepod Chondracanthus goldsmidi,a gill parasite of the striped trumpeter,Latris lineata (Forster), in Tasmania     

M Andrews  S Battaglene  J Cobcroft  M Adams  E Noga  B Nowak 《Journal of fish diseases》2010,33(3):211-220

The chondracanthid copepod, Chondracanthus goldsmidi is an ectoparasite of gills, inner opercula and nasal cavities of cultured striped trumpeter, Latris lineata (Forster). Whilst often present in high numbers (up to 60 parasites per host), little is known about its effect on striped trumpeter. In this study C. goldsmidi was associated with extensive epithelial hyperplasia and necrosis. Pathological changes were most pronounced near the parasite’s attachment site, with papilloma‐like growths surrounding the entire parasite resulting in deformation of the filament. The number of mucous cells increased near the parasite attachment sites on both the opercula and gills. Mast cells were absent in healthy gills; in contrast numerous mast cells were identified in the papilloma‐like growths. Immunostaining identified piscidin‐positive mast cells in the papilloma‐like growths, presenting the first evidence of piscidin in the family Latridae.  相似文献   

Studies on the effect of the HCG injection date on the fertility of ovulation-synchronized gilts     

U Hühn  I K?nig  P Nowak  A L?ffler  W Heidler 《Archiv fuer experimentelle veterinaermedizin》1977,31(6):857-860

The time gap between pregnant mare serum gonadotropine injection (PMSG) and subsequent human chorionic gonadotropine injection (HCG) had major effects, within 72 to 80 hours, on the number of animals with recorded toleration reflex to deadline-oriented insemination as well as on actual fertility. Delay of injections within the above limits always led to higher farrowing and piglet rates. HCG injection was round to be optimally timed when 78-80 hours were allowed to elapse from the preceding PMSG injection.  相似文献   

Stress loading test of slaughter pigs by the injection of succicuran     

A Nowak  K Ender  Y Plesse 《Archiv fuer experimentelle veterinaermedizin》1985,39(6):817-824

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