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Paola Beraldo Maurizio Pinosa Emilio Tibaldi Bartolomeo Canavese 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):89-99
The authors studied a population of 582 gilthead sea breams (Sparus aurata), aged 25–600 days, in order to describe the abnormalities of the opercular complex.
Particular attention was paid to: (1) the different degrees of abnormality of the opercular complex as a whole and of the individual dermal bones (preopercle, interopercle, subopercle and opercle) that compose it; (2) the ways in which the operculum folds into the gill cavity and the relevant histological characteristics. This study discusses the origin and nature of the abnormalities.
Though these abnormalities have a major impact on market value and product image, and are often linked to other disorders in fish, they are still difficult to eliminate. Gaining a basic understanding of these abnormalities will be a first step towards reducing their occurrence. 相似文献
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The scleral bony ring (s. b. r.) of Coturnix coturnix japonica was examined and evaluated mor-phometrically in its characteristic formations (scleral ossicles, overlapping sectors). The modal class14–14, the most representative, was compared to others having minor or major numbers of ossicles with complex or simple overlaps in the left and right eyes. It was observed that the ossicles, numbered as in the literature, are ordered in a characteristic manner to form the s. b. r. The ossicle dimensions are different and numbers 4 and 7 are always smaller and larger. The s. b. r. with different numbers of ossicles compared to the model class14–14 (0,0) showed an evident compensatory behaviour in all classes. In fact, when the ossicle number decreased, single ossicle area increased, retaining a constant s. b. r. area. 相似文献
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We evaluated the osmotic adjustment capacity of leaves and roots of young olive (Olea europaea L.) trees during a period of water deficit and subsequent rewatering. The trials were carried out in Basilicata (40 degrees 24' N, 16 degrees 48' E) on 2-year-old self-rooted olive plants (cv. 'Coratina'). Plants were subjected to one of four drought treatments. After 13 days of drought, plants reached mean predawn leaf water potentials of -0.45 +/- 0.015 MPa (control), -1.65 +/- 0.021 (low stress), -3.25 +/- 0.035 (medium stress) and -5.35 +/- 0.027 MPa (high stress). Total osmotic adjustment increased with increasing severity of drought stress. Trees in the high stress treatment showed total osmotic adjustments ranging between 2.4 MPa at 0500 h and 3.8 MPa at 1800 h on the last day of the drought period. Osmotic adjustment allowed the leaves to reach leaf water potentials of about -7.0 MPa. Active osmotic adjustment at predawn decreased during the rewatering period in both leaves and roots. Stomatal conductance and net photosynthetic rate declined with increasing drought stress. Osmotic adjustment in olive trees was associated with active and passive osmotic regulation of drought tolerance, providing an important mechanism for avoiding water loss. 相似文献
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Protection of farmed camels (Camelus Dromedarius): Welfare problems and legislative perspective 
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下载免费PDF全文 In the last years animal welfare has assumed an increasing interest in our society, influencing legislation to enact many provisions aimed at the protection of animals. Along with increased consumer awareness of the need to maintain ethically acceptable conditions of raised animals, scientists too have begun to investigate the conditions of animal welfare, the tools for its evaluation and for its improvement. Although there are many advances in knowledge, much remains to be investigated concerning many species considered "minor", that is, camels and dromedaries. Dromedaries, recently, have attracted the interest of some breeders following the results of studies concerning the nutritional and therapeutic properties of their products ‐ milk in particular ‐ that make them ideal for some particular categories of consumers, such as diabetics, obesity sufferers, lactose‐intolerant subjects, menopausal women and so on. Considering their use in dairy husbandry, dromedaries are reared under intensive and/or semi‐intensive systems with the resulting emergence of specific needs, which should be fulfilled in order to have appropriate welfare. This paper's purpose is to give practical elements in order to find out dromedary welfare standards, promoting a comprehensive set of regulations on welfare, care and protection of this animal. 相似文献
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The first objective of this study was to search for a possible correlation between accumulation of calcium (Ca), potassium (K), and magnesium (Mg) and fruit transpiration in developing apricot (Prunus armeniaca L.) fruit. Secondly, the work aimed to determine the significance of transpirational flux on Ca nutrition. We hypothesized that if the fruit transpiration is the determining factor of Ca accumulation (phloem‐immobile element) then the import of Ca would be suppressed by restriction of fruit water loss, while the import of phloem‐mobile nutrients (i.e., K and Mg) would not be. To test this hypothesis, the seasonal changes of transpiration and of Ca, K, and Mg concentration/accumulation were assessed in fruits left to naturally transpire or under restricted transpiration (bagged fruits). Fruit transpiration was measured on detached fruits using a portable gas‐exchange equipment (ADC‐LCA4, ADC BioScientific Ltd, Hoddesdon, England). Results demonstrated that 83% of total fruit Ca content was gained within the first 4 weeks after fruit‐set, and that Ca import ceased concomitantly to a reduction of transpiration. In spite of the limitation of fruit transpiration, Ca entered the nontranspiring fruits, and its concentration was about 45% of that in control fruits suggesting that other factor(s) operated for Ca accumulation. This study provides the evidence that fruit transpiration accounted for 55% of total Ca that entered a fruit. We conclude that optimal soil Ca availability and apportioning to the fruit during the early 4 weeks of growth are essential to sustain the fruit demand of this nutrient and that some cultural practices (e.g., summer pruning, irrigation) should be tested as possible tools to improve fruit Ca nutrition via increasing fruit transpiration. 相似文献
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Ferrigno CR Ribeiro AA Rahal SC Orsi AM Fioreto ET Castro MF Mchado MR Singaretti F Ricardo C Augusto A Canavese S Marcos A Ticona E Fernandes M Rita M Singareti F 《Anatomia, histologia, embryologia》2001,30(6):379-381
We herein report a case of a double aortic arch in a 10-week-old male dog of no defined race, which presented episodes of regurgitation at the time of weaning. This vascular malformation was characterized by the persistence of two aortic arches, right and left, of varying dimensions. The right aortic arch was observed to be larger. During post mortem examination the vessels of the animal were injected with coloured latex bi-centrifuged CIS 1-4 polisopreno which revealed the patency of the two aortic arches. Concomitantly, dilation of the cranial oesophagus causing constriction was observed, indicating megaesophagus. Apart from the constriction, the oesophagus presented normal morphometric parameters in relation to its dimensions. 相似文献
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Cannizzo FT Zancanaro G Spada F Mulasso C Biolatti B 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(11):1109-1116
Boldenone and its precursor Boldione are illegally used for anabolic purposes in humans, horses and cattle. To develop more effective policies and programs to maximize food security, Italian Public Health Services investigate all indicators capable of assisting the recognition of treated animals, and prioritize research and the formulation of action strategies for the promotion of healthy eating. Thus, an experimental administration of boldenone and boldione at anabolic dosages in veal calves was carried out to evaluate the changes in target organs by qualitative and semi-quantitative morphological analysis. The lesions resembled the effects already observed after the administration of androgen hormones to cattle. Main findings were represented by prostate hypersecretion, increased rate of apoptotic cells and decreased rate of Ki67 positive cells in the germ cell line of treated animals, particularly in boldione group and finally some new features like hypertrophy of the prostate urothelial cells. 相似文献
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Federico Vessella Javier López-Tirado Marco Cosimo Simeone Bartolomeo Schirone Pablo J. Hidalgo 《European Journal of Forest Research》2017,136(3):555-569
Species distribution models are feasible methods for projecting theoretical responses of living organisms’ occurrence under several future climate change scenarios. The major interest is focused on trees, which regulate the equilibrium within ecosystems and guarantee the survival of many life forms on the Earth. The repercussions of climatic drivers are expected to pose the strongest threats for the Mediterranean biome, an acknowledged hotspot of biodiversity. Here, we focused on cork oak (Quercus suber L.), a keystone species of many landscapes, sustaining a rich biodiversity, ecological processes and economic incomes. Results of 8 combined ecological modelling techniques and two Global Circulation Models highlight a broad contraction of the species potential range over the twenty-first century, both under intermediate and high emissions scenarios. Coupled northward and upward shifts are predicted, mostly pertaining Iberia and North Africa. The potential areas detected at Levantine will likely undergo disappearance. To exacerbate the impacts of climate change, the future of the ecosystems linked to cork oak remains uncertain, because of the expected implications on the phenotypic plasticity or evolutionary responses. A synergy among niche-based, physiological and eco-genetic investigations is strongly needed in the field of applied research, to improve the assessment of conservation and reforestation actions. 相似文献