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1.
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
2.
A. Lindner Dr med vet l; P. von Wittke Dr. med vet; M. Schmald J. Kusserow H. Sommer Dr habil Dr med vet 《Journal of Equine Veterinary Science》1992,12(1)
Lactate kinetics in whole blood of horses was investigated after exercise of differing velocities and duration. The following categories of exercise were used: A: <11 m/second and >180 seconds (n=35), B: >11 m/second and <180 seconds (n=17) and C: <11 m/second and <180 s (n=10). The mean peak lactate concentration determined in horses in category A was 4.49 ± 2.21 mmol/1, in B, 16.32 ± 4.81 mmoVl and in C, 4.58 ± 1.59 mmol/l. While the maximum lactate concentrations in categories A and C were always found immediately after the exercise, the peaks in category B were measured between the first and tenth minute after exercise. Mean lactate concentrations measured at 2-minute intervals after bouts of category-B exercise tended to stabilize 3 to 10 minutes after exercise; however, mean lactate concentrations measured during the intervals before and after the peak value differed significantly. The lactate concentration returned to pre-exercise levels within 20 minutes after exercise bouts of category C, but remained above pre-exercise levels up to 60 minutes after bouts of category-A and -B exercise. It was concluded that, for an evaluation of lactate data after intensive anaerobic exercise, sequential blood sampling at 2-minute intervals for a period of up to 12 minutes after exercise is necessary. Less frequent sampling may be a reason for the often described irreproducibility of lactate concentrations in horses. After aerobic or mild anaerobic exercise, one sample is sufficient, but it has to be taken as soon as possible after exercise. 相似文献
3.
H Adam G von Lengerken D Olthoff M Schwalbe M Wicke 《Archiv fuer experimentelle veterinaermedizin》1989,43(2):293-299
Membraneous phospholipids of subcellular structures were determined from the musculature of German Landrace pigs of the GDR, following exposure to halothane. Mating variants A (H+ male X H+ female), B (H+ male X H- female), and C (H- male X H+ female) were used for positive responders (MHS), while variants B, C, and D (H- male X H- female) were used for negative responders (MHN). Four phospholipid fractions were recorded from the muscle samples for mitochondria and microsomes (according to SR section). Differences between the MHS and MHN groups for the above fractions and without consideration of mating variants and genotype were not observed, although unambiguous responses were exhibited by all animals, either positive or negative to halothan. Significant differences with regard to the above phospholipid fractions were recordable only for variant A (MHS group) as compared to D (MHN), in other words, for the homozygous genotypes, once the above results had been rearranged within MHS and MHN along with different mating variants and genotypes. However, no unambiguous results were obtainable for the heterozygous genotypes of mating variants B and C. Possible underlying reasons are discussed in some detail. The results obtained from mating variants A and D are likely to confirm earlier findings and seem to suggest that the sarcoplasmic reticulum is the primary site of origin of susceptibility to halothane or malignant hyperthermia. 相似文献
4.
Colitis cystica profunda in dogs has been diagnosed in one case only. The two own cases were characterized by repeated, partly bloody diarrhea, vomitus, and painful defecation. The disease was diagnosed by clinical examination and colonoscopy with the ensuing histological examination of biopsy specimens. The disease could be managed by administration of a diet, sulfasalazine and corticosteroids. 相似文献
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8.
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
9.
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
10.
Prognostic value of echocardiographic indices of left atrial morphology and function in dogs with myxomatous mitral valve disease
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