Effects of Natural EstradioI-17β and Synthetic 17α- Ethynylestradiol on Direct Feminization of European Sea Bass Dicentrarchus labrax     

Sergei  Gorshkov Galina  Gorshkova Barbara  Colorni Hillel  Gordin 《Journal of the World Aquaculture Society》2004,35(2):167-177

To produce a monosex female population of European sea bass Dicentrarchus labrax, fry were fed dry diets containing dosages of 12.5, 25, and 50 mg/kg food of either the natural estrogen estradiol-170β(E₂) or the synthetic estrogen 17α-ethynylestradiol (EE₂) for 60 d starting at 88 d post-hatch (dph). A complete feminization (100%) was achieved in all E₂-treated groups at the age of 11 mo (330 dph). All affected fish had ovaries similar in size and histological structure to those of control females. In the E₂-treated groups, feminized fish were heavier and longer than untreated controls (males and females combined). In control groups females exhibited significantly higher body weight and total length than males. Untreated females from control groups and females from the group treated with E₂ at 12.5 mg/kg food had similar body weight, suggesting that in sea bass growth is related to phenotypic sex. In the Entreated groups, survival rates were similar to those of the control fish. A relatively high percentage of females was obtained in the EE₂-treated groups (from 38.6 to 96.5%). However, the gonadal development in these fish was significantly suppressed and a dose-dependent reduction of gonadal sizes was evident. Treatments with the EE₂ (12-5, 25, and 50 mg/kg food) resulted in many fish having abnormal (2.9-5.4-39.8%, respectively) and sterile (0.6-6.0-21.6%, respectively) gonads. Effects also included significantly lower weight and shorter length when compared with controls. Furthermore, fish fed with EE₂ at the dosage of 50 mg/kg food had high mortality rate. A simple protocol was developed for the complete feminization in sea bass in which the fry (80-100 dph) were fed to satiation two times daily with a diet containing 12.5 me of E₂/ks food for a period of 60 d.  相似文献   

Reply     

AJ DART  BA DOWLING 《Australian veterinary journal》2004,82(5):286-287

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Möglichkeiten zur Förderung und zum Einsatz von Nützlingen an Stadtbäumen     

Barbara Jäckel  Hartmut Balder  Kristina Hasselmann 《Gesunde Pflanzen》2002,54(7):218-226

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Carrot red leaf associated RNA in carrots in the United Kingdom     

A. Morton  N. J. Spence †  N. Boonham  D. J. Barbara 《Plant pathology》2003,52(6):795-795

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Preliminary study of plasma vascular endothelial growth factor (VEGF) during low- and high-dose radiation therapy of dogs with spontaneous tumors     

Melanie C. Wergin  Med. Vet.    Kurt Ballmer-Hofer  PhD    Malgorzata Roos  PhD    Roger E. Achermann  Med. Vet.    Natalie Inteeworn  Med. Vet.    Margarete K. Akens  Med. Vet.    Hans Blattmann  PhD    Barbara Kaser-Hotz  Dr. Med. Vet. 《Veterinary radiology & ultrasound》2004,45(3):247-254

High plasma vascular endothelial growth factor (VEGF) concentrations are associated with radiation resistance and poor prognosis. After an exposure to ionizing radiation in cell culture an early phase and a late phase of increased VEGF have been documented. The activation was dependent on the radiation dose. Therefore, the purpose of this study was to measure baseline plasma VEGF and changes in VEGF over the course of fractionated radiation therapy in dogs with spontaneous tumors. Dogs with tumors had a significantly higher pretreatment plasma VEGF than did dogs without tumors. Immediately after irradiation no increased plasma VEGF was observed. Over the course of radiation therapy there was an increased plasma VEGF in dogs treated with low doses per fraction/high total dose, whereas plasma VEGF remained stable in dogs irradiated with high doses per fraction/low total dose. The regulatory mechanisms are very complex, and therefore the value of plasma VEGF measurements as an indirect marker of angiogenesis induced by radiotherapy is limited.  相似文献   

Characterization of a wild-type strain of Francisella tularensis isolated from a cat.     

Thomas J Inzana  Gretchen E Glindemann  Gerald Snider  Susan Gardner  Lisa Crofton  Barbara Byrne  Joseph Harper 《Journal of veterinary diagnostic investigation》2004,16(5):374-381

Francisella tularensis type A is the primary cause of tularemia in animals and humans in North America. The majority of research on F. tularensis has been done with the attenuated live vaccine strain (LVS), which is a type B, but very few wild-type F. tularensis strains have been characterized. A gram-negative coccobacillus that was isolated in pure culture from the lungs of a cat that died after being lost for 5 days was received for identification at the Virginia-Maryland Regional College of Veterinary Medicine Teaching hospital. The isolate (strain TI0902) was not identified (or was misidentified) by commercial identification systems; however, it was identified as F. tularensis subspecies tularensis (type A) by sequencing a portion of the 16S ribosomal RNA gene. Furthermore, repetitive extragenic palindromic sequences-polymerase chain reaction amplified a 4-kb DNA fragment from TI0902 that was characteristic of F. tularensis type A but not type B. The electrophoretic profile of the lipopolysaccharide of strain TI0902 was identical to that of the LVS by Western blotting with antiserum to LVS. The protein-enriched outer membrane of strain TI0902 contained 6-8 proteins, which were similar in molecular size to those from the LVS. Electron microscopy of negatively stained and alcian blue-stained LVS and TI0902 cells showed that both strains were coccobacillary in shape and may be encapsulated. However, after mouse challenge, the TI0902 strain was clearly more virulent than the LVS strain. Results of this study indicate that the genotype and phenotype of wild-type F. tularensis type A strain TI0902 is similar, but not identical, to that of the LVS strain. Further studies will help determine whether pathogenesis and host-pathogen interactions are also similar between the 2 strains.  相似文献   

Prognostic value of echocardiographic indices of left atrial morphology and function in dogs with myxomatous mitral valve disease          下载免费PDF全文

Marco Baron Toaldo  Giovanni Romito  Carlo Guglielmini  Alessia Diana  Nazzareno G. Pelle  Barbara Contiero  Mario Cipone 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(3):914-921

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A survey of northern Victorian dairy farmers to investigate dairy calf management: colostrum feeding and management          下载免费PDF全文

AJ Phipps  DS Beggs  AJ Murray  PD Mansell  MF Pyman 《Australian veterinary journal》2018,96(4):101-106

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.

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Equine pituitary pars intermedia dysfunction: current understanding and recommendations from the Australian and New Zealand Equine Endocrine Group          下载免费PDF全文

CJ Secombe  SR Bailey  MA de Laat  KJ Hughes  AJ Stewart  JM Sonis  RHH Tan 《Australian veterinary journal》2018,96(7):233-242

The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.  相似文献   

Validation of the Accutrend Plus point‐of‐care triglyceride analyzer in horses,ponies, and donkeys          下载免费PDF全文

Michaela C. Pongratz Dr. med vet  DECEIM  FVH  Hannah K. Junge Dr. med vet  Barbara Riond Dr. med vet  FVH  Colin C. Schwarzwald Dr. med vet  PhD  DACVIM  DECEIM 《Journal of Veterinary Emergency and Critical Care》2016,26(5):682-690

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