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991.
1. In two separate experiments, the possibility of detecting embryonic development in chicken eggs was assessed using the same spectrophotometric method used to detect blood in Table eggs, using a combination of two wavelengths (577 and 610 nm) of the transmission spectrum. 2. In the first experiment, during the first 10 d of incubation, transmission spectra of 30 Hisex White eggs and 30 Hybro eggs were measured daily. 3. In the second experiment, 292 Hisex White eggs were incubated. Seven groups were randomly assigned. Six received an injection of sodium azide (NaN3) at different times during incubation in order to stop embryonic development, and during the first 12 d of incubation the transmission spectrum was measured daily. The acoustic resonance analysis method was also used on a group of uninjected eggs. 4. In the first experiment, it was possible to detect embryonic development from 120 h of incubation onwards in fertile eggs. In the second experiment changes in light transmission due to embryonic development were detected from 108 h of incubation. Detection of embryonic development using the acoustic resonance analysis method in the second experiment was possible only from 120 h of incubation. 5. It was concluded that the detection of embryonic development using visible light transmission is not directly linked with the formation of blood, but with the formation of sub-embryonic fluid, which takes place from 72 h of incubation onwards. This fluid makes the yolk sac translucent so that absorption of light at 577 nm can be detected. 相似文献
992.
Elsinghorst TA 《The Veterinary quarterly》2002,27(4):183-189
Summary The study concerned 123 Journals of the category "Veterinary Sciences" as defined in the Journal Citation Reports (?, Institute for Scientific Information (ISI), Philadelphia, USA). Using Web of Knowledge (?, ISI, USA), update December 3, 2005, articles published in 2002 and 2003 and cited 20 times or more were selected. The total number of selected articles was 96. They were published in 34 out of the 123 journals. Based on the country of the first author, the articles originated form 24 countries. Forty-nine of the 96 articles (51%) were written in only two countries being England (15) and the USA (34). The articles could be classified in six categories being immunology (21), microbiology and directly related subjects (48), prions and prion-induced diseases (5), reproduction (23), toxicology (3), and miscellanea (11). The category "microbiology" (48) was divided into six subcategories: general (1), bacteriology (17), mycology (3), parasitology (5), protozoology (6), and virology (5). Some articles were classified in more than one (sub)category. 相似文献
993.
A rostrocaudal (RCd) nasal view was developed in large breed mesaticephalic dogs using a complete, subsequently sectioned, skull and cadaver specimens to optimise the radiographic technique and evaluate normal anatomic features. Gelatin was placed in one nasal passage of the cadaver specimens to mimic the effects of nasal pathology. The latter specimens and 18 clinical cases with suspected nasal disease were evaluated to determine the usefulness of the RCd view compared to standard nasal views. An optimal RCd view was obtained with the dog in dorsal recumbency and the head symmetrically positioned with the hard palate perpendicular to the table using a table top technique with 8:1 grid, collimating to the nasal region and centring the primary beam on the philtrum. The dorsolateral aspects of the maxillary bone, the nasal bones, septal sulcus of the vomer, mucosa lined nasal septum and conchae could be seen. A centrodorsal more radiolucent area representing the ethmoid bone region was also visible. Gelatin soft tissue opacification of the nasal passage could be seen more clearly in RCd nasal view than in occlusal dorsoventral view. In clinical cases the RCd view was useful to build up a 3-dimensional image of nasal passage pathology as well as to detect nasal septum and osseous nasal border pathology not visible in other views. This view is particularly useful in cases where cross-sectional imaging modalities are not available or where the nasal investigation is limited by cost considerations. 相似文献
994.
Komatsu Y Itoh N Taniyama H Kitazawa T Yokota H Koiwa M Ohtsuka H Terasaki N Maeno K Mizoguchi M Takeuchi Y Tanigawa M Nakamura T Watanabe H Matsuguchi Y Kukino T Honma A 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(9):482-486
Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types. 相似文献
995.
Hinchcliff KW Lauderdale MA Dutson J Geor RJ Lacombe VA Taylor LE 《Equine veterinary journal》2002,34(1):9-16
High intensity exercise is associated with production of energy by both aerobic and anaerobic metabolism. Conditioning by repeated exercise increases the maximal rate of aerobic metabolism, aerobic capacity, of horses, but whether the maximal amount of energy provided by anaerobic metabolism, anaerobic capacity, can be increased by conditioning of horses is unknown. We, therefore, examined the effects of 10 weeks of regular (4-5 days/week) high intensity (92+/-3 % VO2max) exercise on accumulated oxygen deficit of 8 Standardbred horses that had been confined to box stalls for 12 weeks. Exercise conditioning resulted in increases of 17% in VO2max (P<0.001), 11% in the speed at which VO2max was achieved (P = 0.019) and 9% in the speed at 115% of VO2max (P = 0.003). During a high speed exercise test at 115% VO2max, sprint duration was 25% longer (P = 0.047), oxygen demand was 36% greater (P<0.001), oxygen consumption was 38% greater (P<0.001) and accumulated oxygen deficit was 27% higher (P = 0.040) than values before conditioning. VLa4 was 33% higher (P<0.05) after conditioning. There was no effect of conditioning on blood lactate concentration at the speed producing VO2max or at the end of the high speed exercise test. The rate of increase in muscle lactate concentration was greater (P = 0.006) in horses before conditioning. Muscle glycogen concentrations before exercise were 17% higher (P<0.05) after conditioning. Exercise resulted in nearly identical (P = 0.938) reductions in muscle glycogen concentrations before and after conditioning. There was no detectable effect of conditioning on muscle buffering capacity. These results are consistent with a conditioning-induced increase in both aerobic and anaerobic capacity of horses demonstrating that anaerobic capacity of horses can be increased by an appropriate conditioning programme that includes regular, high intensity exercise. Furthermore, increases in anaerobic capacity are not reflected in blood lactate concentrations measured during intense, exhaustive exercise or during recovery from such exercise. 相似文献
996.
Neurological dysfunction is an uncommon complication following extrahepatic portosystemic shunt ligation. Three dogs and one cat are described that developed neurological signs within 21 to 42 hours of attenuation of intrahepatic portosystemic shunts. None of these cases had biochemical evidence of hepatic encephalopathy postoperatively. Two dogs died during management of status epilepticus following aspiration of food. One dog died six months postoperatively. The cat had persistent neurological dysfunction at discharge, but was alive and had recovered most of its neurological function at the time of writing, 37 months after surgery. This report demonstrates the potential for animals with intrahepatic portosystemic shunts to develop postoperative neurological signs and highlights the difficulty of managing such cases. Two dogs had both intrahepatic and extrahepatic portosystemic shunts. Large intestinal malrotation (partial situs inversus) may have been linked to the development of a portosystemic shunt in the remaining dog. 相似文献
997.
998.
Epileptic seizures can lead to various reactions in the brain, ranging from neuronal necrosis and glial cell activation to focal structural disorganization. Furthermore, increased hippocampal neurogenesis has been documented in rodent models of acute convulsions. This is a report of hippocampal neurogenesis in a dog with spontaneous epileptic seizures. A 16-week-old epileptic German Shepherd Dog had marked neuronal cell proliferation (up to 5 mitotic figures per high-power field and increased immunohistochemical expression of proliferative cell nuclear antigen) in the dentate gyrus accompanied by microglial and astroglial activation. Some granule cells expressed doublecortin, a marker of immature neurons; mitotically active cells expressed neuronal nuclear antigen. No mitotic figures were found in the brain of age-matched control dogs. Whether increased neurogenesis represents a general reaction pattern of young epileptic dogs should be investigated. 相似文献
999.
The objective of this retrospective study is to determine normal reference values for 2-Dimension (2D) and Motion-mode (M-mode) echocardiographic parameters in nonsedated healthy young adult Sphynx cats and to compare them to those of the domestic shorthair (DSH). 131 Sphynx cats underwent cardiac screening prior to breeding. The control group consisted of 30 healthy adult domestic cats. A complete cardiac ultrasound was performed on all cats using right parasternal long and short axis views. There were few echocardiographic parameters in the Sphynx that differed from those of the healthy DSH. Only the left atrial (LA) dimension in 2D and M-mode, the left atrial/aortic (LA/Ao) ratio and the internal dimension of the left ventricle in systole (LVIDs) measured with M-mode were different. In conclusion, although the heart of Sphynx cat can often have a particular 2-D echocardiographic appearance, the M-mode cardiac dimensions are similar to those of the DSH. 相似文献
1000.