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421.
Recently, new agricultural policies and European Directives brought to important changes in farming practice, some of which could affect food availability for the wild bird population endangering biodiversity. This study aims to evaluate the consequences of such agricultural changes in France on the woodpigeon's dietary regimen. A total of 1,093 woodpigeons were collected over a four-year period (2014–2017). Voluntary sampling was performed in six regions in the south-west of France by local hunters during this species’ autumnal migration and wintering. Ingluvies contents were recovered, macroscopically and microscopically identified, and then weighed before and after drying. Five food groups were identified: acorns, corn, green plant material, cultivated seeds and others. ANOVA testing followed by Tukey's test for multiple comparison were performed (R version 3.5.2). Significance was set at p < .05. A total of 762 woodpigeons met the study's inclusion criteria. Mean weight of total crop contents was less of 9 grams of dry matter. Most frequent food groups were “green plant material” (70.3%), acorns (42.3%) and corn (27.2%). In terms of grams of dry matter, the most important food in the crop content were acorns (62%): these were eaten more during the first two hunting seasons (p < .001), and in region A, lower amount was consumed compared to all other regions. On the contrary, corn intake peaked during the third year (p < .001), and in region A, birds had an increasing intake of this cereal. Cultivated seeds contributed to the diet more during migration (p = .007), while “green plant material” and others more during wintering (p = .011; p = .004). In conclusion, results confirm the opportunistic nature of the woodpigeon, balancing its diet according to food availability. Corn was eaten more in areas where the winter burying of chopped maize stover (mulching), provided by the Nitrate's directive, was in derogation.  相似文献   
422.
Representatives of three types of feruloyl esterases were examined for their ability to release mono- and di-meric ferulic acid from water-extractable and water-unextractable cereal cell wall material, either alone or in the presence of a family 10 or family 11 xylanase. A type-C feruloyl esterase from Talaromyces stipitatus (TsFaeC) released 100% of the ferulic acid from water-extractable wheat endosperm arabinoxylan when acting in combination with a xylanase from Trichoderma longibrachiatum. The type-A esterase from Aspergillus niger, AnFaeA, was most effective in releasing ferulic acid from wheat bran and brewers' spent grain, with over 50% of the available ferulic acid being released from wheat bran in the presence of a xylanase from Bacillus subtilis. In general, family 11 xylanases were the preferred synergistic partners with feruloyl esterases for the release of ferulic acid, while family 10 xylanases were preferred for the liberation of diferulic acid, with only the 5,5′ form being released by the action of AnFaeA alone. This suggests that ferulic acid may be located in regions of low substitution on arabinoxylans while the 5,5′ diferulate moiety is located in more branched regions of the xylan chain.  相似文献   
423.
Under the assumption that milk yield may be reduced in herds with impaired welfare, the present study aimed at investigating whether milk yield could be used as a reliable indicator of welfare. In 125 commercial French dairy herds, the association between the welfare of the herd (evaluated using the Welfare Quality assessment protocol) and cow milk yield was investigated using linear mixed models. Positive associations were identified between milk yield and low aggressions between cows and good emotional state of the herd but there was a negative association with good health assessed through the occurrence of diseases and injuries. These opposite associations resulted in no association with the overall welfare of the herd. Milk yield should not therefore be used as an indicator of overall welfare.  相似文献   
424.
Photosynthetic organisms adapt to changes in light quality by redistributing light excitation energy between two photosystems through state transition. This reorganization of antenna systems leads to an enhanced photosynthetic yield. Using a genetic approach in Chlamydomonas reinhardtii to dissect the signal transduction pathway of state transition, we identified a chloroplast thylakoid-associated serine-threonine protein kinase, Stt7, that has homologs in land plants. Stt7 is required for the phosphorylation of the major light-harvesting protein (LHCII) and for state transition.  相似文献   
425.
Articular cartilage defects are one of the features of osteoarthritis in animals and humans. Early detection of cartilage defects is a challenge in clinical veterinary practice and also in translational research studies. An accurate, diagnostic imaging method would be desirable for detecting and following up lesions in specific anatomical regions of the articular surface. The current prospective experimental study aimed to describe the accuracy of computed tomographic arthrography (CTA) for detecting cartilage defects in a common animal model used for osteoarthritis research, the ovine stifle (knee, femoropatellar/femorotibial) joint. Joints in cadaver limbs (n = 42) and in living animals under anesthesia (n = 13) were injected with a contrast medium and imaged using a standardized CT protocol. Gross anatomy and histological assessment of specific anatomic regions were used as a gold standard for the evaluation of sensitivity, specificity, negative predictive value, and positive predictive value for CTA identification of articular cartilage defects in those regions. Pooled estimated sensitivity and specificity were 90.32% and 97.30%, respectively, in cadaver limbs, and 81.82% and 95.24%, respectively, in living animals. Pooled estimated positive predictive value and negative predictive values were 98.25% and 85.71%, respectively, in cadaver limbs, and 81.82% and 95.24%, respectively, in living animals. The delineation of cartilage surface was good for anatomical regions most frequently affected by cartilage defects in the ovine stifle: medial femoral condyle, medial tibial condyle, and patella. This study supported the use of CTA as an imaging technique for detecting and monitoring articular cartilage defects in the ovine stifle joint.  相似文献   
426.
Floods are known to be the major source of natural variability and disturbance in stream ecosystems. However, the management and channelisation of large rivers have impacted the fluvial geomorphology and disconnected the main channel and floodplains used as nurseries by many species of fish. This study examines the influence of a first autumnal flood event of the Ardèche River on the roach population, Rutilus rutilus (Linnaeus, 1758), in the Caderousse reach on the Rhône River. This influence was evaluated through an analysis of the spatial distribution for the abundance and size of juvenile roach and an analysis of otolith shape. Juvenile roach from the three sections of the reach formed well‐defined local populations before and after the flood event. Juvenile roach were always more abundant in the less modified section (BPS) of the river than in the other sections (RES and TAIL). While the original primary river channel was directly impacted by the flash flood, no significant difference in otolith shape was observed before or after the flash flood. Our results suggest that this part of the reach provides refuge habitats used by fish during high flow events.  相似文献   
427.
Indicators of pulmonary hypertension in dogs examined with thoracic computed tomography (CT) are not well established in the veterinary literature. In humans, the main pulmonary artery to aortic diameter ratio (MPA:Ao) measured via CT, has been shown to be more sensitive than echocardiographic variables for predicting presence and severity of pulmonary hypertension, in some cases. In veterinary literature, the MPA:Ao has been determined echocardiographically to have an upper limit of about 1:1. Measurement of this ratio has not been described in dogs using CT. The objectives of this cross‐sectional, prospective study were to compare echocardiographic measurement of MPA:Ao with that obtained via CT, determine if measurement of MPA:Ao via CT is repeatable and reproducible, and determine the effect of respiration and contrast administration on the measurement of MPA:Ao via CT. Ten healthy dogs without pulmonary hypertension were anesthetized to undergo thoracic CT using three protocols and echocardiography. The MPA:Ao was measured three times by three observers for each of the three CT protocols and compared to echocardiographic measurements. The mean MPA:Ao measured among all observers and CT protocols was 1.108 ± 0.152 (SD). The effect of CT scan protocol on MPA:Ao significantly differed among the three methods (P = 0.0014), where expiratory scans had lower MPA:Ao than inspiratory scans. The ratio measured on inspiratory CT scans consistently overestimated MPA:Ao when compared to echocardiography (bias = 0.226). Findings did not support the echocardiographically derived upper limit of MPA:Ao as an upper limit for determination of main pulmonary arterial enlargement on CT.  相似文献   
428.
An adult male giant panda (Ailuropoda melanoleuca) was presented with a cutaneous mass ventral to the eye. The animal was anesthetized and the mass was surgically excised. Histopathologic examination determined that the mass was a benign cavernous hemangioma, the first reported case in a giant panda.  相似文献   
429.
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