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31.
A survey was carried out in 25 riding centers to evaluate the prevalence of behavioral problems among saddle horses and to investigate the relationship between these and individual traits, training and management of the affected horses. Seven percent of the 650 horses examined had some kind of behavioral problems, and crib-biting was the most frequent. These behavioral problems seemed to be related to the sort of training and management. Show jumping horses tended to be affected simultaneously by more than one behavioral problem and to be more aggressive towards other horses. Although show jumpers were ridden more often, they had fewer opportunities to graze. The prevalence of behavioral problems was lower among those horses ridden Western style than among those ridden English style; the latter employs more hand to bit contact. The study also showed that horses groomed and ridden by one and the same person had more problems than horses groomed and ridden also by different people.  相似文献   
32.
Background, Aim and Scope  The toxicity of contaminated sediments should be evaluated considering the direct exposure of laboratory organisms to whole sediments and the indirect exposure to elutriates or extracts (Tay et al. 1992, Byrne and Halloran 1999, Nendza 2002). The alga Dunaliella tertiolecta is indicated for the use in toxicity bioassays because it is highly sensitive to several xenobiotics. Harpacticoid copepods have been already used for toxicity testing and Tigriopus fulvus is a promising Mediterranean target-species in ecotoxicology (Todaro et al. 2001, Faraponova et al. 2003, Pane et al. 2005a). In this study, the toxicity of sediments collected in harbour sites of the Northeastern Adriatic Sea was evaluated by growth inhibition test with free living and alginate-immobilized Dunaliella tertiolecta and acute toxicity test with nauplii and adult Tigriopus fulvus with the aim of pointing out the importance to utilize model organisms from different trophic levels in sediment ecotoxicology. Methodology  Elutriates and whole sediments were tested on free living and immobilized (Pane et al. 1998) algal cells, and on laboratory reared copepods. Free-living D. tertiolecta were exposed to diluted elutriates in a static, multi-well plate system. Naalginate immobilized D. tertiolecta were placed in polystyrene inserts fitted with polyester mesh bottoms and exposed to a thin layer (2 mm) of whole sediments in multi-well plates (EPS 1992, Pane and Bertino 1999). Toxicity tests with copepods were carried out on Tigriopus fulvus nauplii (elutriates) and adults (whole sediments and elutriates). Same-aged nauplii useful for toxicity tests were obtained by egg sac detaching and consequent hatching stimulation (Pane et al. 2006). Newborn nauplii (I–II stage) were exposed to elutriates in multi-well plates provided with polystyrene inserts. Adult T. fulvus maintained in polystyrene inserts fitted with polyester mesh bottoms were placed in contact with a thin layer (2 mm) of whole sediment placed on multi-well plate bottoms. All end-points were evaluated after 96 h. Results  In general, the effects increased with the increasing of elutriate concentration up to 50%; the stimulation or inhibition of algal growth was statistically significant in comparison to the control. The inhibiting elutriates induced EC50 variations of algal growth ranging from 66.9% to 74.3%. The mortality of T. fulvus nauplii was always < 25% after treatment with 100% elutriates and < 10% after treatment with 50% dilution; no effect was shown up with 25% dilution; therefore LC50 was not calculable. The effect of elutriates was negligible on adult copepods and LC50 values were never calculable; percent mortality always resulted in < 10% after treatment with whole sediments. Discussion  Both experimental systems gave substantially similar results after exposition to whole sediments and elutriates. During the experiment with algal cells, the immobilization in Na-alginate and the employment of inserts which allowed the contact of organisms with sediments and their easy counting were particularly useful. Likewise, the employment of inserts of adequate mesh size in the tests with copepods allowed the contact of organisms with the sediment and made organism handling and counting easy, as well as the evaluation of mortality. The methodology here described and the utilization of the proposed test-species could have an importance also considering that the current trend in ecotoxicological research is towards finding the most appropriate organism for specific areas of concern by using indigenous species (Mariani et al. 2006) and towards the major significance of chronic and reproductive end-points. Conclusions  Based on the above results, it can be stated that the bioassay with Dunaliella tertiolecta could be a good estimation tool for the ecotoxicological assessment of marine sediments. The immobilization of algae in Na-alginate was seen to be useful to evaluate the toxicity of whole sediments; the employment of polystyrene inserts allowed an improvement of the procedures. T. fulvus nauplii and adults, as other harpacticoids such as Tigriopus japonicus (Yoon et al. 2006), satisfy the basic criteria for the employment of a standard species in marine bioassays. To date only pelagic Acartia tonsa are utilized in the standardized procedure to evaluate the risk assessment of chemicals or wastewaters (ISO 1999). As, on the contrary, the exposure of copepods to solid-phase contaminants it is not yet standardized, the employment of polystyrene inserts improved the procedures for T. fulvus too. So, the rapidity and the possibility to solve practical problems could be the main attractive features of this technique (Pane et al. 2005a) when applied to whole sediments. Recommendations and Perspectives  The methodology here developed being also applicable to long term and reproduction tests should be recommended because it provides relevant information in comparison with other frequently applied, standardized biotests with crustaceans (ISO 1999). The procedure has been shown to be easily applicable to selected marine organisms. ESS-Submission Editor: Prof. Dr. Henner Hollert (henner.hollert@bio5.rwth-aachen.de)  相似文献   
33.
Tacle and Clara [Monreal clementine (Citrus clementina Hort. ex Tan) x Tarocco orange (Citrus sinensis L. Osbeck)] are two new triploid citrus hybrids developed by the CRA-Istituto Sperimentale per l'Agrumicoltura (Acireale, Italy). The fruits are easy-peeling and juicy, have a pleasant taste like the Tarocco orange, and are sweet like the Monreal clementine. In addition, a distinctively attractive characteristic of these mandarin-like fruits is the red-pigmented flesh caused by the presence of anthocyanins. This study reports the juice quality attributes of fresh fruits harvested at different ripening stages and of cold-stored fruits kept for 104 days at 6+/-1 degrees C and 90-95% relative humidity. Physico-chemical analyses showed that the fresh-fruit juice yield ranged between 39 (Tacle) and 41% (Clara); these values were 11-14% lower after 104 days of storage. Vitamin C content in the Clara juice was decisively higher than that in the Tacle juice. Juice anthocyanins and other polyphenols increased during cold storage. These results show that low-temperature storage enhances the functional attributes of Tacle and Clara fruit juices.  相似文献   
34.
A rapid, one‐step agglutination assay has been developed, based on latex particles sensitized with antibodies against vitellogenin (Vtg), aimed at Atlantic bluefin tuna, Thunnus thynnus (Linnaeus) (ABFT), gender identification. The egg‐yolk precursor protein Vtg was used as a gender marker for the assay as it is a female‐specific protein synthesized during reproductive maturation. The presence of Vtg in the plasma was revealed in 60–120 s through an agglutination reaction by mixing small volumes of ABFT plasma and an anti‐Vtg antibody‐latex suspension on a microscope slide. The effectiveness of the present test was restricted to the months of May and June, concomitant with high circulating Vtg levels. Because of its rapidity and ease of performance in the field, the present gender identification assay could be useful for broodstock management in the aquaculture industry as well as in tagging studies on wild populations.  相似文献   
35.
This paper describes the case of a 2-year-old English Bulldog with severe teratozoospermia that consisted mainly of "Dag-like" defects, which is strong coiling of the tail. Although libido, semen volume and sperm concentration were normal, sperm motility was 5.0%, and 93.3% of spermatozoa exhibited morphological abnormalities affecting the tail. Transmission electron microscopic examination of the spermatozoa revealed strong folding, coiling and fracture of sperm midpieces and tails, axonemal defects and the presence of swollen and unevenly distributed mitochondria. Taking into account the dog's history and examinations and the constantly high percentage of abnormal spermatozoa over time, the defect was considered to be genetic in origin.  相似文献   
36.
An automated on-line solid-phase extraction-liquid chromatography-electrospray tandem mass spectrometry (SPE-LC-ESI-MS/MS) method was developed for the determination of ochratoxin A (OTA) in alcoholic beverages. Mean recoveries for wine and beer were, respectively, 75 and 82%. Detection was achieved in negative ionization with a Q TRAP mass spectrometer operating in multiple-reaction monitoring (MRM) mode or enhanced product ion (EPI) mode, using the third quadrupole as linear ion trap. The MRM mode turned out to be more sensitive; the method allowed accurate determination of OTA in the range of 0.01-25 ng mL(-1) using external calibration. Within-day and between-day relative standard deviation percentages were <6.2 and <9.1%, respectively. In EPI mode, fragmentation spectra at the limit of quantification (0.03 ng mL(-1)) and good linearity could be obtained. Application of the method (MRM mode) to the analysis of several wine and beer samples purchased in local stores revealed OTA levels in the ranges of 0.03-1.44 ng mL(-1) for wines and 0.02-0.14 ng mL(-1) for beers.  相似文献   
37.
The aim of this study was to assess the effects of earliness (according to FAO class), maturity stage at harvest and environmental conditions on the ensilability of maize hybrids described by their fermentation products and by a fermentation quality index (FQI). Maize hybrids belonging to early (n = 14) and late (n = 15) FAO classes were grown in low, medium and high potential yield areas and harvested at an early (EH), medium (MH) and late maturity stage (LH), that is, at 1/3, 2/3 and 5 d after the 2/3 milk line stage, respectively, according to a split‐plot design. Upon harvest, each sample (n = 522) was analysed for dry matter (DM) and water‐soluble carbohydrates (WSC) before being ensiled in vacuum‐packed bags (n = 1,044). After 60 days of conservation, samples were analysed for DM and fermentation products. In the pre‐ensiling phase, DM was higher in early hybrids (p = .001), low yield areas (p < .001) and at LH maturity (p < .001), whereas WSC contents were higher in early hybrids (p < .001), medium yield areas (p < .001) and at EH maturity (p < .001). With regard to silages, early hybrids had a higher FQI (p < .001), which was highest in areas with a high yield potential (p < .01) and at EH maturity (p < .01). Late hybrids proved to be better suited for low yield areas compared with early hybrids (p < .01) and had a higher FQI at EH and MH than at LH maturity (p < .01).  相似文献   
38.
The effects of four humic substance (HS) samples, a soil humic acid and two humic acids and one fulvic acid isolated from a composting substrate, were evaluated on the mycelial growth of Fusarium oxysporum f. sp. melonis (FOM) and F. oxysporum f. sp. lycopersici (FOL). In general, any HS treatment reduced significantly the radial growth of the FOM mycelium either in normal [potato dextrose agar (PDA) medium] or sub-optimal (water–agar medium) nutritional conditions. Differently, the FOL growth, which was tested only on PDA, was either inhibited or stimulated on dependence of the HS treatment used. The HS fractions isolated from the composting substrate were the most effective inhibitors of mycelial growth of both fungi. Furthermore, any HS treatment was also able to alter the germination process of FOL in aqueous medium, not only by reducing significantly the number of viable germinating conidia but also by generally decreasing the rate of conidial germ-tube elongation. Apparently, the extent of the inhibitory action was related to some chemical and functional properties of HS, such as the COOH group content and elemental composition.  相似文献   
39.
Nitrate contamination of groundwater represents a threat to human health. Many researchers have studied zerovalent iron as a mean to remediate nitrate contamination. However, the application of such method is limited by ammonium production. This work investigates the use of microscale iron particles in association with zeolitite, a natural material containing zeolite, to remove nitrate and ammonium from groundwater. The association of the two materials is shown to lower the nitrate concentration in both deionized water and groundwater under the limit suggested by the European Union and to significantly reduce the ammonium concentration. The method is potentially applicable in water filtration.  相似文献   
40.
The aim of the present study was to analyze the effects of drug detection training on behavior and blood neurotransmitter levels in drug detection dogs so as to investigate some variables influencing dog reactivity and responsiveness to training. In all, 20 dogs were sampled out of the Guardia di Finanza canine population. All the subjects were born, reared, housed, and trained in the same facility and followed the same training sessions. Dogs’ behavioral reactivity was scored according to a standardized working dogs test to evaluate natural dog attitudes. Plasma samples were analyzed by the high-performance liquid chromatography method to evaluate adrenaline, noradrenaline, L-3,4-dihydroxyphenylalanine, homovanillic acid (HVA), 3-methoxy-4-hydroxyphenylglycol acid (MHPG), 5-hydroxyindole acetic acid (5-HIAA), and 5-hydroxytryptamine (5-HT) levels. 5-HT and 5-HIAA were also analyzed from platelets. The analysis was carried out considering training, breed, and sex as independent variables. From a behavioral point of view, significant differences were recorded before and after training in “sociability,” “playfulness,” “predatory instinct,” and “aggressiveness” scores. Lower levels of platelet 5-HT and 5-HIAA were found after training. Plasma L-3,4-dihydroxyphenylalanine levels differed between sexes, with males showing higher concentrations. These results underline the importance of complete and objective evaluations protocols of the dogs before, during, and after drugs search training to determine effective and successful selection strategies and training procedures.  相似文献   
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