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91.
The aim of this study was to analyze the breed identity and leadership in a mixed flock of sheep. The flock consisted of 89 Suffolk adult ewes and 250 Columbia ewes and 45 Columbia rams. The animals were kept in the pasture during the day. Each hour the flock was allowed to feed for 20 minutes, and then was moved for 40 minutes to a small paddock near the grazing area. In the afternoon, all sheep were taken to the night pen. The animals were observed for 120 days, 4 times a day (480 leadership breed positions), with respect to the following conditions: (1) leave pen at front of flock, (2) return to pen at front of flock, (3) first to move to the grassland, (4) return to the paddock, (5) drink first (on arrival time at the night pen), and (6) preference for an area in the night barn. The Suffolk breed were first in leaving (94% of the times) and in returning to the night pen (65%) (P < 0.05), and 35% returned with the Columbia sheep. The Suffolk breed were first to move to the grazing area (90%) and 10% moved with the other breed (P < 0.05). When returning to the rest area, the Columbia sheep were first to reach 54% of the time, the 2 breeds were together 29% of the time, and the Suffolk sheep were alone 17% of the time (P < 0.05). When comparing who drank first, 50% of the time both breeds went together, 28% of the time the Columbia sheep were first, and 22% of the time the Suffolk sheep were first (P < 0.05). At night, most of the Suffolk sheep had a preference for 1 barn area (P < 0.05). The results of our study suggest that most animals of each breed performed activities together. Suffolk sheep were leaders when moving to the grazing area and when selecting the place to rest.  相似文献   
92.

• Introduction  

The abandonment of rural areas has led to an increase of the fire-prone European gorse (Ulex europaeus L.) communities in some regions, where prescribed burning is a technique applied to control them. Understanding flammability changes after treatments is crucial for the sustainable use of fire.  相似文献   
93.
The serological characteristics of a group of 32 Pseudomonas anguilliseptica strains isolated in Spain from seabream (Sparus aurata) and turbot (Scophthalmus maximus) were compared with a total of 18 collection strains of this bacterial species with different geographical and host origin. The employment of different techniques, including slide agglutination, microagglutination and dot blot, allowed us to establish two serological groups, one comprising practically all the eel isolates, and the other including the majority of isolates from other fish species. The study of the lipopolysaccharides (LPS) and outer membrane proteins (OMP) corroborated these results, indicating that the serological differences among strains are due to the somatic antigen and not to antigenic determinants of protein nature. Therefore, a serological scheme of two "O" serotypes is proposed for P. anguilliseptica. The results obtained will be of importance for epidemiological studies as well as for the design of adequate vaccine formulations.  相似文献   
94.
During the last 50 years human anisakiasis has been rising while parasites have increased their prevalence at determined fisheries becoming an emergent major public health problem. Although artificial enzymatic digestion procedure by CODEX (STAN 244-2004: standard for salted Atlantic herring and salted sprat) is the recommended protocol for anisakids inspection, no international agreement has been achieved in veterinary and scientific digestion protocols to regulate this growing source of biological hazard in fish products. The aim of this work was to optimize the current artificial digestion protocol by CODEX with the purpose of offering a faster, more useful and safer procedure for factories workers, than the current one for anisakids detection. To achieve these objectives, the existing pepsin chemicals and the conditions of the digestion method were evaluated and assayed in fresh and frozen samples, both in lean and fatty fish species. Results showed that the new digestion procedure considerably reduces the assay time, and it is more handy and efficient (the quantity of the resulting residue was considerably lower after less time) than the widely used CODEX procedure. In conclusion, the new digestion method herein proposed based on liquid pepsin format is an accurate reproducible and user-friendly off-site tool, that can be useful in the implementation of screening programs for the prevention of human anisakiasis (and associated gastroallergic disorders) due to the consumption of raw or undercooked contaminated seafood products.  相似文献   
95.
The present paper describes new symptoms on Eucalyptus spp. in Central Italy associated with the fungal pathogen Pestalotiopsis biciliata. This fungal species has been previously recorded in Italy on grape associated with fruit rot. Artificial inoculation trials on leaves confirmed the pathogenicity of the fungus to Eucalyptus camaldulensis. P. biciliata is included in the list of Pestalotiopsis spp. responsible for leaf disease on eucalypts worldwide.  相似文献   
96.
New Forests - Elms (Ulmus spp.) were once dominant trees in mixed broadleaf forests of many European territories, mainly distributed near rivers and streams or on floodplains. Since ancient times...  相似文献   
97.
Wine is an important source of dietary antioxidants because of its phenolic compound content. The antioxidant activity (AA) of pure monomer substances present in wines, such as phenolic acids, flavanols, and anthocyanins, has already been described, but the AA of polymeric phenols is still unknown. In this study, we have fractionated a red wine by countercurrent chromatography (CCC) into four fractions: fraction 1, made up of polymeric compounds; fraction 2, containing malvidin-3-glucoside; fraction 3, containing peonidin-3-glucoside; and fraction 4, containing vitisin A. The AA of these fractions was determined by oxygen radical absorbance capacity and ferric reducing ability assays. The weight of fraction 1 was the largest, so this was the largest contributor to the AA of the wine. However, the antioxidant powers (muM Trolox/g fraction) of fractions 2-4 were similar and higher than that of fraction 1. We also determined AA before and after in vitro gastric and intestinal digestions. After gastric digestion, the AA was 100-1000 times higher than the original fraction values. Gallic acid was determined in gastric and intestinal digested fractions. After intestinal digestion, the concentrations of simple phenols, such as caffeic acid, p-coumaric acid, and protocatechualdehyde, increased as they were released from the fractions under our conditions. Protocatechuic acid was determined in more intestinal digested fractions than in gastric digested fractions. These results partly explain the increase in AA after the digestion and indicate the relevance of polymeric polyphenolic compounds as precursors of smaller molecules with biological activity.  相似文献   
98.
The aims of our study were to compare the effectiveness of poultry manure (PM) and banana waste (BW), with regard to their use as inoculant carriers of a bacterial consortium constituted by strains of Azospirillum, Azotobacter and P-solubiliser bacteria and to establish the most efficient dose of biofertilizer for a soil cultivated with banana (Musa paradisiaca AAA Simmonds), with respect to improving plant performance and soil physical and microbiological properties. Six months after planting, plant growth had increased with increase in dose of the biofertilizers applied. The biofertilizer prepared on BW enhanced the density of P-solubiliser bacteria, the concentrations of available P and foliar P to a greater extent than with the biofertilizer prepared on PM. The increases produced by the biofertilizer prepared on PM for the soil aggregate stability, enzymatic activities and the labile carbon fractions were highly correlated to the dose applied. Both biofertilizers can be considered potentially useful as inoculant carriers of PGPR but the usefulness of BW appears to be restricted to moderate doses of application (≤3%).  相似文献   
99.
The phenotypic characteristics and growth kinetics at several temperatures, salinities, and pH values of three Vibrio parahaemolyticus (Vp) strains with different virulence and one nonpathogenic strain were evaluated. Independent of the virulence of the strain, a high metabolic diversity was found, which yielded different colored phenotypes on the CHROMagar? Vibrio. All strains were resistant to ampicillin and carbenicillin, and Vp AHPND+ organisms were the most sensitive to enrofloxacin. The exponential growth of Vp strains started at 1–2 hr of incubation, although no relationship was observed between the bacterial density and degree of virulence. Moreover, the growth of the most virulent strain was independent of the nutrients in the incubation media during the initial hour postinoculation. No strain grew at 4°C in 0% NaCl and pH 4, but only Vp AHPND+ grew at 44°C. For all strains, the lag phase was proportional to the NaCl concentration, and the growth was better at pH 8–9. However, the Vp AHPND? strain displayed a greater variability, was more sensitive to extreme conditions, and showed a lag phase of 9 hr independent of the pH.  相似文献   
100.
The aim of this study was to evaluate the performance of commercial heartworm antigen tests in dogs harbouring Dirofilaria immitis microfilariae near its distribution limit in South America. A total of 4934 blood samples of adult dogs from Southern Greater Buenos Aires were examined to detect circulating microfilariae in the buffy coat interface between December 2005 and April 2006. Microfilariae were detected in 88 (1.8%) blood samples and all the microfilariae observed were identified as D. immitis by acid phosphatase stain technique. In a first trial, 69 (78.4%) out of the 88 serum were positive by Speed((R)) Diro. Then, a new test was performed over 25 microfilariae-positive serum samples randomly selected among the 88 previously tested samples and using simultaneously Speed((R)) Diro, Witness((R)) Dirofilaria and Snap((R)) 3dx. This second trial showed identical results for the three different tests, in which 19 (76%) samples were positive. Therefore, more than 20% of microfilaremic dogs were antigen negative. The main hypothesis that could explain our finding is a low worm burden in the study area. According to our preliminary results, it is highly recommendable the complementary use of antigen tests and other procedures to obtain an accurate diagnostic near the distribution limit of the parasite.  相似文献   
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