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61.
62.
Transpalpebral ultrasonographic measurement of the optic nerve sheath diameter in healthy dogs 下载免费PDF全文
Joshua J. Smith DVM Daniel J. Fletcher PhD DVM DACVECC Stacy D. Cooley DVM DACVR Margret S. Thompson DVM DACVR 《Journal of Veterinary Emergency and Critical Care》2018,28(1):31-38
Objective
To develop a reference range for ultrasonographically measured optic nerve sheath diameter (ONSD‐US) in dogs. We hypothesized that ONSD‐US can be measured reliably and is associated with weight but not age, sex, or body condition score (BCS), and that the relationship between weight and ONSD‐US in dogs is allometric due to canine size variations.Design
Prospective, observational study.Setting
University teaching hospital.Animals
Seventy‐eight healthy adult dogs.Interventions
The ONSD was measured by a standardized transpalpebral approach.Measurements and Main Results
Regression analysis showed the relationship between weight and ONSD was better fit with a linear model (R2 = 0.8510) than an allometric model (R2 = 0.7917). Multiple regression analysis showed ONSD is associated with weight (P < 0.0001), age (P = 0.0021), and BCS (P = 0.0007), but not with sex. Dominance analysis showed 94.6% of the variance explained by the model was due to weight. Intraclass correlation coefficient (ICC) analysis showed excellent interobserver (ICC = 0.9338–0.9608) and intraobserver (ICC = 0.9893) reliability.Conclusions
These results suggest that ONSD‐US may be reliably measured in dogs using our described transpalpebral approach, and we have calculated prediction intervals based on body weight. Future studies are needed to determine if ONSD‐US measurements are associated with intracranial hypertension as shown in human medicine. 相似文献63.
Previous investigations failed to demonstrate mast cells in the alimentary tract and extraparietal glands of the ferret. It was decided therefore to test this and assess factors that may be of influence. Major salivary glands and tongues of mature ferrets, which had been fixed in formalin-calcium, were examined by means of light microscopical histochemistry. Staining of paraffin sections with techniques depending on basic dyes or esterolytic activity was carried out for conventional times with and without previous oxidation, hot acid hydrolysis, and trypsin and beta-glucuronidase digestion. Aldehyde fuchsin and high iron diamine consistently revealed the presence of few mast cells in interstitial stroma of salivary glands and lingual musculature, and in the lamina propria of lingual mucosa. Alcian blue at 0.5 M MgCl2 and safranin produced less consistent results, and even fewer metachromatic mast cells were detected. No staining of mast cells was obtained with the technique for naphthol AS-D chloroacetate esterase. Pretreatment did not increase the numbers and/or staining reactions of mast cells. The results refute the previous misconception and suggest that ferret is a species with a low incidence of mast cells largely expressing a connective-tissue phenotype. 相似文献
64.
Fang H Howroyd PC Fletcher AM Diters RW Woicke J Sasseville VG Bregman CL Freebern WJ Durham SK Mense MG 《Veterinary pathology》2007,44(3):407-410
Subendothelial heart valve angiectasis has been reported in cows, dogs, pigs, rats, mice, and in human fetuses and newborns. We observed a high incidence (62 in 208 animals examined) of spontaneous angiectasis on the atrioventricular (AV) valves in 10- to 40-week-old Sprague-Dawley rats. The angiectasis was observed predominately on the septal cusp of the right AV valve and located near the AV ostium in 57 of 62 animals. Of the remaining 5 valvular angiectases, 2 were present on the parietal cusp of the right AV valve and 3 were on the left AV valve. The angiectases were single or multiple, ranging from 40 to 300 microm in diameter and were characterized by light microscopy as blood-filled dilatations lined by endothelium. Spontaneously occurring abnormalities in normal laboratory animals, such as the spontaneous valvular angiectasis reported here, need to be differentiated from drug-related lesions. 相似文献
65.
Julie A. Churchill Daniel A. Feeney Thomas F. Fletcher Carl A. Osborne David J. Polzin 《Veterinary radiology & ultrasound》1999,40(6):642-647
Under controlled, but varied dietary conditions 35 geriatric, uninephrectomized, spayed Beagle bitches (dogs) observed for 4 years, renal cortical and renal medullary echogenicity was measured relative to hepatic and splenic echogenicity. Regardless of the diet fed, 60-75% of these aged dogs had renal cortical echogenicity less than that of either the liver or spleen across time; 25-35% of these dogs had renal cortical echogenicity equal to that of the liver, but less than that of the spleen across time. Less than 3% of these dogs had renal cortical echogenicity greater than that of the liver, but less than that of the spleen. Only 1 (one) of these dogs had renal cortical echogenicity equal to that of the spleen and that occurred at only one of the 14 chronologic assessments. Therefore, in either mature or aged dogs imaged with 4.0 to 5.0 MHz equipment, the renal cortical echogenicity should be considered normal if it is less than or equal to that of the liver and less than that of the spleen. In 29 dogs imaged with the 4.0/5.0 MHz equipment and 6 dogs imaged with 7.5 MHz equipment, there was no significant diet or individual dog effect. The 7.5 MHz (6 dog) group had significantly higher average cortical echogenicity scores than the 4.0/5.0 MHz (29 dog) group. However, the occurrence of renal cortical echogenicity greater than liver echogenicity was seen in only 5 of 83 samples (approximately 6.0%) made on 6 dogs imaged with 7.5 MHz equipment and only 1 of 375 samples (approximately 0.27%) made on 29 dogs with 4.0/5.0 MHz equipment. With the exception of one occurrence, all dogs had renal medullary echogenicity less than that of the liver or spleen regardless of imaging equipment frequency. The renal medulla was always hypoechoic compared to the cortex. 相似文献
66.
C. G. M. Paxton J. M. Fletcher D. P. Hewitt I. J. Winfield 《Ecology of Freshwater Fish》1999,8(2):78-84
Abstract– Analysis of the Windermere (England), Perca fluviatilis (1965–1997) and Esox lucius (1943-1997) fishery data indicates there have been substantial changes in sex ratios through time. In the case of perch, a 1976 perch disease outbreak substantially skewed the sex ratio in favor of females. It took over a decade for the fishery to recover to its pre-1976 state. In the case of pike, both catch and year-class data are female biased, but this bias has significantly weakened through time. This trend towards proportionately more males through time may reflect an effect of increasing spring temperatures or an evolutionary or phenotypic response to female-biased fishing pressure. 相似文献
67.
Larval pigmentation, survival and growth of Penaeus indicus fed the nematode Panagrellus redivivus enriched with astaxanthin and various lipids 总被引:1,自引:0,他引:1
The highly unsaturated fatty acid (HUFA) content of the free-living nematode Panagrellus redivivus was successfully increased when three different lipid sources (cod-liver oil, marilla oil and capelin oil) from marine animals were used in the nematode culture medium. The lipid enrichment significantly increased the ω3 HUFA content, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), of the nematodes compared with lipid non-enriched nematodes. Penaeus indicus larvae fed the lipid-enriched nematodes had significantly ( P < 0.05) greater larval survival (69–77%) until metamorphosis than those fed non-enriched nematodes (54%).
This nematode species was also enriched with astaxanthin to determine the effects of this carotenoid on pigmentation, survival and growth during the larval development of P. indicus . The pigment, delivered via nematodes, significantly ( P < 0.05) improved larval coloration and survival (88%) compared with that of placebo-pigmented nematodes (78%). However, there was no strong evidence to show the benefit of either pigment and/or lipid enrichment on larval growth and development of P. indicus .
This study has shown that the nutritional value of the nematodes can be enhanced by the addition of fish oil into the culture medium. Supplementation of EPA and DHA, together with synthetic astaxanthin, allow the nematodes to be used as a sole diet for the larval culture of P. indicus . 相似文献
This nematode species was also enriched with astaxanthin to determine the effects of this carotenoid on pigmentation, survival and growth during the larval development of P. indicus . The pigment, delivered via nematodes, significantly ( P < 0.05) improved larval coloration and survival (88%) compared with that of placebo-pigmented nematodes (78%). However, there was no strong evidence to show the benefit of either pigment and/or lipid enrichment on larval growth and development of P. indicus .
This study has shown that the nutritional value of the nematodes can be enhanced by the addition of fish oil into the culture medium. Supplementation of EPA and DHA, together with synthetic astaxanthin, allow the nematodes to be used as a sole diet for the larval culture of P. indicus . 相似文献
68.
69.
Development of a Pseudomonas syringae–Eutrema salsugineum pathosystem to investigate disease resistance in a stress tolerant extremophile model plant 下载免费PDF全文
To improve the ability to understand how plants respond to multiple and/or concurrent stresses, disease resistance was investigated in Eutrema salsugineum, an extremophile model plant that is highly tolerant of abiotic stress. Compared to Arabidopsis (Col‐0), both Yukon and Shandong Eutrema accessions exhibit increased resistance to Pseudomonas syringae pv. tomato DC3000 (Pst) and pv. maculicola (Psm), with Shandong Eutrema exhibiting greater resistance to Pst than Yukon Eutrema. RT‐PCR of the EsPR1 (Pathogenesis‐related 1) defence marker gene confirmed RNA‐Seq data that healthy Shandong Eutrema constitutively expresses EsPR1. The data suggests that Shandong Eutrema exists in a highly primed state of defence preparedness, as it displays heightened resistance compared to defence‐primed natural accessions of Arabidopsis (Can‐0, Bur‐0). Pathogen‐triggered PR1 expression was delayed in Yukon Eutrema; however, these plants were resistant to Pst suggesting that Yukon Eutrema employs a PR1‐independent mechanism to resist Pst. This study demonstrates that Eutrema is an excellent model to investigate biotic stress tolerance. The Eutrema–P. syringae pathosystem will facilitate future studies to understand how this extremophile tolerates both abiotic and biotic stress, and will allow exploration of the interplay of these responses to inform efforts to improve stress tolerance in crops. 相似文献
70.
Defining the critical nitrogen concentration (Nc; g N kg?1) for maximum growth of forage brassicas will aid in the fertilizer management of these crops. Typically, the Nc value decreases with increasing crop biomass. In this paper, we used a nitrogen (N) response experiment with kale (Brassica oleracea) to define a critical N dilution (Nc = 55·3 × biomass?0·47). However, at biomass <3·4 t ha?1, a constant NC of 31·2 g N kg?1 was found. This N dilution curve compared favourably with published data sets for a range of forage brassicas but was substantially different from the established N dilution curve for oilseed rape (Brassica napus). This study also found a strong relationship (R2 = 0·81) between the nitrogen nutrition index (NNI) and the NO3 content of forage brassicas from a range of data sets. The NNI is the actual N concentration of the shoot as a ratio of the Nc from the established curve. The relationship between NNI and NO3 contents was significantly different between leafy forage brassica crops and root forage brassicas. For each 0·1 increase in NNI, the proportion of total N that was in the form of NO3 increased by 2·7% for leaf/stem brassicas and 0·60% for root crop brassicas. The critical dilution curve defined in this study can be used to manage fertilizer N in forage brassica crops, so that growth can be maximized but the risk of high NO3 concentrations in the forage can be minimized. 相似文献