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641.
The objective of the present study was to describe the arthroscopic anatomy of the bovine fetlock joint using one palmar/plantar and three dorsal joint approaches. A comparative anatomic, ultrasonographic and arthroscopic study using 20 cadaveric feet from 13 non-lame adult dairy cows was performed. Arthroscopy was accomplished using a rigid arthroscope to view the synovial cavities with their synovial villi and parts of the following structures: the distal ends of the metacarpal/metatarsal III/IV bones with their trochleae and sagittal ridges, synovial grooves, the articular surfaces of the proximal sesamoid bones, the proximal aspects of the first phalanges, the lateral and medial collateral ligaments, the suspensory ligament and the interdigital ligaments as parts of the interosseus muscle, the cruciate sesamoidean ligaments, the communication site between the lateral and medial pouch in the palmar/plantar area, and dorsally the septum between the lateral and the medial pouch. The technique allowed a good overall view of most relevant structures in the sound cadaver joint. Further investigations are warranted to evaluate the diagnostic, therapeutic and prognostic applications of these techniques in the treatment of septic arthritis.  相似文献   
642.
The analyzed material included 40 hybrid rabbits slaughtered at the age of 90 days. The control group was transported directly after weaning, while the transport group was transported directly prior to slaughter. The experiment was designed to assess the transport stress, carcass and meat quality implications, taking into account the muscle type and sex. The transported animals were characterized by a higher level of blood cortisol, glucose and triglycerides (P < 0.0001), and a lower level of insulin (P < 0.0001) compared to the control group. In the presented study the time post‐mortem affected the pH decline in both rabbit groups (P < 0.0001). The lightness, redness and yellowness of rabbit meat were affected by the transport (P < 0.0001, P = 0.001 and P < 0.0001). The percentage of free water and its share in the total water was higher for the non‐transported rabbits compared to the transported ones (P < 0.0001). Moreover, the meat from the control group was characterized by greater plasticity compared to the transport group (P = 0.003). The chemical composition of rabbit meat was not changed by the effect of transport (P = 0.643–0.979). To conclude, the quality traits of meat from the transported hybrid rabbits clearly indicated the development of dark firm and dry‐like lower quality of meat.  相似文献   
643.
Strawberries are a common and important fruit in human diet because of their high content of essential nutrients and beneficial phytochemicals, which have relevant biological activity in human health. In this study, six cultivars and 15 selected F1 hybrids between S4 inbred lines and tester (cv. ‘Dukat’) were evaluated in a field trial over a period of two consecutive years. The amounts of total anthocyanin, phenolics and vitamin C in fruits and antiradical activity were analysed. General combining ability (GCA) and mid‐parent heterosis were also determined for those characteristics. Among all the genotypes tested, the inbred lines of ‘Senga Sengana’ 17 showed the highest breeding value based on GCA for all studied traits. Estimated heterosis varied among genotypes tested. The highest heterosis in terms of vitamin C occurred in the offspring of clone 1387 18‐15 × ‘Dukat’, but with regard to phenols and antiradical activity in hybrid ‘Teresa’ 18‐15 with cv. ‘Dukat’. This study revealed that the differentiation in chemical composition of strawberry fruits between genotypes is clearly dependent on individual genotype combinations and demonstrated the presence of heterosis in phytochemical contents in some specific genotypic combinations.  相似文献   
644.
Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem‐based perspective, using objective and evidence‐based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long‐term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem‐based management and governance, sustainable fisheries and healthy ecosystems go together.  相似文献   
645.
Eighty 6-years-old Quercus ilex L. subsp. ballota seedlings planted on a former agricultural land were subjected during two growing seasons to one of four treatments: fertilization and irrigation, irrigation, fertilization, and control. Seasonal and between-treatment variations on water relations, gas exchange parameters, growth and nutrient status were analyzed. Water potential () was related to climatic conditions. Thus, the frequent rain storms during the summer allow seedlings to maintain relatively high values, joined to moderate photosynthetic activity. Differences on , photosynthesis and stomatal conductance due to irrigation were shown at the onset and end of growth, related with lower water availability. Fertilization had a greater effect on growth than irrigation. Both fertilization and irrigation positively affected the relative increment on leaf nutrient concentration at the end of the second year. The results indicate that water availability was not a limited factor, thus irrigation is not justified; while fertilization improve growth.  相似文献   
646.
Contents Poly(ADP-ribose) polymerase (PARP) synthesizes poly(ADP-ribose) in response to DNA strand breaks using NAD+ as a substrate. It leads to consequences for metabolism not only on a cellular level, but also on a tissue level, among others: NAD+ and ATP depletion. Retention of foetal membranes (RF) in cows is supposed to be connected with the imbalance between production and neutralization of reactive oxygen species, leading to oxidative damage to DNA, lipids and proteins. The aim of this preliminary study was to detect the presence of PARP in bovine placenta and to describe the enzyme with respect to type of placental tissue, time and mode of delivery. Placentomes, collected after spontaneous delivery or caesarian section, were divided into maternal and foetal parts of placenta, homogenized, and subjected to electrophoresis. Cows were divided into six groups as follows: (A) caesarian section before term with RF, (B) caesarian section before term without RF, (C) spontaneous delivery at term with RF, (D) spontaneous delivery at term without RF, (E) caesarian section at term with RF, (F) caesarian section at term without RF. PARP was detected by Western blotting using commercially available bovine anti PARP antibody. Bands referred to as bovine PARP standard were present in all examined tissues as well as the products of its cleavage. However, the patterns of bands were different with respect to type of tissue, time, and mode of delivery. Further experiments on detailed relationship between PARP activity and the process of releasing and retaining of bovine placenta are necessary.  相似文献   
647.

Context

Climate change is not occurring over a homogeneous landscape and the quantity and quality of available land cover will likely affect the way species respond to climate change. The influence of land cover on species’ responses to climate change, however, is likely to differ depending on habitat type and composition.

Objectives

Our goal was to investigate responses of forest and grassland breeding birds to over 20 years of climate change across varying gradients of forest and grassland habitat. Specifically, we investigated whether (i) increasing amounts of available land cover modify responses of forest and grassland-dependent birds to changing climate and (ii) the effect of increasing land cover amount differs for forest and grassland birds.

Methods

We used Bayesian spatially-varying intercept models to evaluate species- and community-level responses of 30 forest and 10 grassland birds to climate change across varying amounts of their associated land cover types.

Results

Responses of forest birds to climate change were weak and constant across a gradient of forest cover. Conversely, grassland birds responded strongly to changing climatic conditions. Specifically, increasing temperatures led to higher probabilities of localized extinctions for grassland birds, and this effect was intensified in regions with low amounts of grassland cover.

Conclusions

Within the context of northeastern forests and grasslands, we conclude that forests serve as a possible buffer to the impacts of climate change on birds. Conversely, species occupying open, fragmented grassland areas might be particularly at risk of a changing climate due to the diminished buffering capacity of these ecosystems.
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