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71.
Reynolds B Taillade B Médaille C Palenché F Trumel C Lefebvre HP 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(3):339-340
BACKGROUND: The effect of repeated freeze-thaw cycles on plasma constituents has not been assessed in dogs, although such a procedure is not uncommon to use in routine laboratory practice. OBJECTIVE: To assess the effect of freeze-thaw cycles on routine plasma constituents in healthy dogs. METHODS: Six healthy adult dogs were used. Blood was sampled and placed in heparinized tubes. After centrifugation, plasma was separated into 5 aliquots. One aliquot was considered as the reference aliquot and used immediately for the assay of all of the biochemical constituents. All of the other aliquots were stored at 20 degrees C. Three aliquots underwent 1, 2, or 3 freeze-thaw cycles during a 1- to 3-day period. The last aliquot remained at 20 degrees C throughout the study and was thawed on the third day. The following biochemical constituents were assayed: glucose, urea, creatinine, total proteins, sodium, potassium, chloride, calcium, phosphates, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), and alkaline phosphatase (ALP). RESULTS: No clinically relevant change was observed between the different aliquots for all of the constituents. CONCLUSION: Repeated freeze-thaw cycles do not cause changes in the biochemical constituents studied in canine plasma. 相似文献
72.
Catherine Breton Alain Gil Julie Wargnier Hervé Serieys André Bervillé 《Euphytica》2012,186(2):557-572
Common sunflower (i.e., Helianthus annuus) is occasionally crossed with other Helianthus species to gain favourable agronomic traits. An interspecific cross between H. annuus and Helianthus mollis was used to examine events that occurred during the five first generations. First generation hybrid plants were verified using GISH, and F1 hybrid (#17) was back-crossed to common sunflower to obtain BC1 (#4) and BC2 (#21). Some BC2 progeny possessed new traits, i.e., compact (Compact plant architecture is due to short inter-node length, short petiole length and short leaf lamina length) architecture without and with corrugated leaves, which were not observed in the parents. These traits were selected for and fixed after the BC2-S3 (#18) to produce a H. mollis introgression line (namely HM374). Although the size of the population was small, we tentatively construct a genetic map using data from the BC2 generation. Two linkage groups were identified carrying H. mollis specific AFLP markers that were associated with compact plant architecture, and one unlinked marker was shown to explain variation for the corrugated leaves. Introgression line HM374 was used to test the inheritance of compact plant architecture in a cross with an elite high oleic line, OL75HO. Microsatellite (SSR) markers were used to genotype F1 and F2 offspring’s. Our data suggested that the line HM374 was still heterozygous for introgression after eight generations. HM374 displays new architecture traits (i.e. compact architecture with or without corrugated leaves) and carries H. mollis fragments anchored on LG1 and LG11 of sunflower public map. 相似文献
73.
74.
R. R. Doce A. Belenguer P. G. Toral G. Hervás P. Frutos 《Journal of animal physiology and animal nutrition》2013,97(1):48-57
Three experiments were conducted to study the effect of the administration of young leaves of Quercus pyrenaica (OL) on in vivo ruminal fermentation in relation to oak tannin toxicosis in cattle. In Experiment 1, six bulls were fed up to 5 kg fresh matter (FM) of OL per animal and day for 14 days. In Experiment 2, another six bulls were first subjected to severe feed restriction for 8 days and then fed a higher amount of OL (approximately 10 kg FM daily) for 3 days. In Experiment 3, three bulls received the same amount of OL as in Experiment 1 for 6 days, but adding a severe feed restriction as in Experiment 2. In situ DM disappearance of grass hay and OL, and pH and ammonia and volatile fatty acid concentrations were recorded throughout the three assays. Daily administration of up to 5 kg OL did not considerably affect ruminal fermentation, unless it was preceded by a severe feed restriction period. Administration of 10 kg OL preceded by undernutrition triggered a critical reduction in rumen fermentation activity concomitantly with an acute intoxication. Interestingly, some results differ from those observed previously in vitro, which highlights the importance of validating in vitro data with in vivo measurements, given the complexity of extrapolation in ruminants. 相似文献
75.
Chetboul V Sampedrano CC Concordet D Tissier R Lamour T Ginesta J Gouni V Nicolle AP Pouchelon JL Lefebvre HP 《American journal of veterinary research》2005,66(6):953-961
OBJECTIVE: To determine left ventricular free wall (LVFW) radial and longitudinal myocardial contraction velocities in healthy dogs via quantitative 2-dimensional color tissue Doppler imaging (TDI). ANIMALS: 100 dogs. PROCEDURE: TDI was used by a single trained observer to measure radial and longitudinal myocardial movement in the LVFW. Radial myocardial velocities were recorded in segments in the endocardial and epicardial layers of the LVFW, and longitudinal velocities were recorded in segments at 3 levels (basal, middle, apical) of the LVFW. RESULTS: LVFW velocities were higher in the endocardial layers than in the epicardial layers. Left ventricular free wall velocities were higher in the basal segments than in the middle and apical segments. Radial myocardial velocity gradients, defined as the difference between endocardial and epicardial velocities, were (mean +/- SD) 2.5 +/- 0.8 cm/s, 3.8 +/- 1.5 cm/s, and 2.3 +/- 0.9 cm/s in systole, early diastole, and late diastole, respectively. Longitudinal myocardial velocity gradients, defined as the difference between basal and apical velocities, were 5.9 +/- 2.2 cm/s, 6.9 +/- 2.5 cm/s, and 4.9 +/- 1.7 cm/s in systole, early diastole, and late diastole, respectively. A breed effect was detected for several systolic and diastolic TDI variables. In all segments, systolic velocities were independent of fractional shortening. CONCLUSIONS AND CLINICAL RELEVANCE: LVFW myocardial velocities decreased from the endocardium to the epicardium and from base to apex, thus revealing intramyocardial radial and longitudinal velocity gradients. These indices could enhance conventional echocardiographic analysis of left ventricular function in dogs. Breed-specific reference intervals should be defined. 相似文献
76.
Chetboul V Lefebvre HP Pinhas C Clerc B Boussouf M Pouchelon JL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(1):89-95
Systemic hypertension was diagnosed in 58 of 188 untreated cats referred for evaluation of suspected hypertension-associated ocular, neurologic. cardiorespiratory, and urinary disease, or diseases frequently associated with hypertension (hyperthyroidism and chronic renal failure). Hypertensive cats were significantly older than normotensive subjects (13.0 +/- 3.5 years versus 9.6 +/- 5.0 years; P < .01), and had a greater prevalence of retinal lesions (48 versus 3%; P < .001), gallop rhythm (16 versus 0%; P < .001), and polyuria-polydipsia (53 versus 29%: P < .01). Blood pressure was significantly higher (P < .001) in cats with retinopathies (262 +/- 34 mm Hg) than in other hypertensive animals (221 +/- 34 mm Hg). Hypertensive cats had a thicker interventricular septum (5.8 +/- 1.7 versus 3.7 +/- 0.64 mm; P < .001) and left ventricular free wall (6.2 +/- 1.6 versus 4.1 +/- 0.51 mm; P < .001) and a reduced diastolic left ventricular internal diameter (13.5 +/- 3.2 versus 15.8 +/- 0.72 mm; P < .001) than control cats. Left ventricular geometry was abnormal in 33 of 39 hypertensive subjects. No significant difference was found in age or blood pressure at the initial visit between cats that died or survived over a 9-month period after initial diagnosis of hypertension. Mean survival times were not significantly different between hypertensive cats with normal and abnormal left ventricular patterns. Further prospective studies are needed to clearly identify the factors involved in survival time in hypertensive cats. 相似文献
77.
The use of tanniferous plants or tannins represents one alternative approach to the control of gastrointestinal parasites in ruminants but most data have been obtained in sheep. The current study was therefore performed in goats with two objectives: firstly, to investigate the effects of condensed tannins (CT) on adult populations of Trichostrongylus colubriformis and Teladorsagia circumcincta; secondly, to examine their effects on the establishment of infective larvae of these two species. In experiment 1, two groups of kids were infected with 6 000 L3 of T. colubriformis and 6 000 L3 of T. circumcincta. After 7 weeks, quebracho extracts were administered per os for 8 days to one group. A comparable group which did not receive tannins was included as the control. The kids were slaughtered on week 11. Parasitological and pathophysiological parameters were measured weekly. Worm counts were assessed and mast cells, globule leukocytes and eosinophils were counted in the abomasal and intestinal mucosae. Tannin administration was associated with a decrease in egg excretion, and a decrease in female fecundity, but with no changes in worm numbers. These changes were associated with an increased number of intestinal mast cells. In experiment 2, 24 goats were used according to a 2 x 2 factorial design, depending on infection and tannin administration. Two groups were either infected with 6 000 L3 of T. colubriformis or T. circumcincta. Within each group, the goats were either drenched or undrenched with tannin extracts. Pathophysiological parameters were measured weekly. Twelve days after the cessation of tannin administration, the goats were slaughtered. Worm counts and female worm fecundity were determined. Tannin consumption was associated with a significant reduction (P < 0.01) of Trichostrongylus populations and a close to significant reduction for Teladorsagia. No effect on fecundity was observed. Our results (1) confirm the consequences of condensed tannins on nematodes in goats as in sheep and (2) indicate divergent effects depending on the parasitic stage exposed to the condensed tannins. 相似文献
78.
A case of multiple congenital epitrichial sweat gland hamartomas in a 2-day-old piglet is presented. The skin lesions were raised, ovoid to linear in configuration, alopecic, red-purple to pink, and cauliflower-like to cerebriform in appearance. Histological examination of skin specimens confirmed a diagnosis of epitrichial sweat gland hamartoma. Complete necropsy examination revealed no other lesions. 相似文献
79.
J L Puech C Mertz V Michon C Le Guernevé T Doco C Hervé Du Penhoat 《Journal of agricultural and food chemistry》1999,47(5):2060-2066
Brandies, cognac, armagnac, whiskeys, and rums are aged in oak barrels to improve their organoleptic properties. During this period, numerous compounds such as ellagitannins are extracted from the wood and can subsequently be transformed into new derivatives by chemical reactions. Model solutions of castalagin and vescalagin have been studied to determine the behavior of polyphenols in ethanol-water. Upon prolonged exposure to 40 and 70% (v/v) ethanol at room temperature, hemiketal derivatives containing ethoxy groups have been characterized by LC/MS and NMR. These compounds further evolve to afford the corresponding ketals. They have also been detected in the extracts of oak wood stored under similar conditions. 相似文献
80.
The riparian forests along braided rivers are dynamic, frequently rejuvenated by floods and channel changes, and thus dominated
by pioneer to middle stages of succession; they are sites of high biodiversity in some regions. The Lower Eygues River (drainage
area 1150 km2 in southeastern France) is such a braided river system with large alluvial forests dominated by Salix alba, Populus alba, and P. nigra. It was identified as a site of ecological interest by the EU under the Natura 2000 program. Such forests elsewhere in Europe have been identified as reference ecosystems. We documented the historical evolution
of this alluvial forest from detailed (1:2500 scale) early 19th C parcel maps, early 20th C topographic maps, aerial photography
from 1947 to 1996, and field surveys of topography and riparian vegetation in 1997–1998. Our results show that in 1830, the
channel was wide, aggraded, and agricultural pressure extended literally to the channel edge. With decline in the rural population
and reduced agricultural and grazing pressure in the catchment, erosion rates declined. Reduced sediment supply led to channel
narrowing and incision. This channel narrowing, coupled with reduced agricultural pressure along the banks, has allowed riparian
forest to colonize former active channel areas, especially within late 19th-century 20th century flood dykes. In recent decades,
aggregate mining, and clearing for recreation and agriculture have fragmented the forest. Thus, the alluvial forest of the
Lower Eygues is largely an artifact of changing human land-use over the past century, a context that should frame efforts
for preservation and restoration. 相似文献