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Fusarium circinatum is the causal agent of pitch canker, a destructive disease that threatens natural and planted pine forests around the world. Although pitch canker has caused problems in Spain and Portugal, concerning Europe as a whole, the fungus is not established across the pine distribution area. Its dispersion by wind and/or insect vectors could nevertheless play a role in the colonization of currently uninfected stands. It is therefore crucial to develop monitoring tools for its detection. To this end, we assessed the molecular detection of the pathogen in environmental samples of bark beetles and passive spore traps, collected in two infected Pinus radiata plantations in Basque country, Spain. The spread pattern of F. circinatum was assessed by an experimental design that included insect and spore traps installed at the centre, at the edge and outside the plots. Our results showed that F. circinatum was detected in both types of samples, at almost all collection dates. In both type of samples, positive detections were mainly found at the centre of the plots, a lower proportion at the edge, and very few outside. This suggests that long‐distance dispersion of Fusarium circinatum does not rely on wind spore dispersal neither on insect flight. Our study also shows that molecular methods are a powerful tool to monitor the pathogen in environmental samples.  相似文献   
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The corneal endothelium is essential for the maintenance of the corneal transparency. The aim of this study was to examine the morphology of the endothelial surface and perform morphometric analysis of the normal corneal endothelial cells of the Magellanic penguin (Spheniscus magellanicus) using scanning electron microscopy. The present work demonstrates that the corneal endothelium of the Magellanic penguin is similar to those described in other vertebrates.  相似文献   
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The effects of frame size (FS) and body condition score (BCS) on performance of Brahman cows were evaluated using records collected from 1984 to 1994 at the Subtropical Agricultural Research Station, Brooksville, Florida. Age at puberty (AP), calving rate (CR), calving date (CD), survival rate (SR), weaning rate (WR), birth weight (BWT), weaning weight (WWT), preweaning ADG, and kilograms of calf produced per cow exposed (PPC) were obtained from first- (n = 215), second- (n = 130), and third or greater-parity (n = 267) dams. Based on hip height at 18 mo of age, heifers were assigned to three FS groups: small (115 to 126 cm), medium (127 to 133 cm), or large (134 to 145 cm). Small and medium FS heifers attained puberty at younger (P<.05) ages (633.2+/-12.3 and 626.4+/-12.0 d) than large FS heifers (672.3+/-17.1 d). Calving rate in large FS second-parity dams was 27% less (P<.05) than in small and medium FS dams. In third or greater-parity dams, CR was greater (P<.05) for small FS cows than for medium and large FS cows. Across the three parity groups, CR improved with increasing BCS. Except for the first-parity dams, animals with better fall BCS calved earlier (P<.05). In first-parity dams, SR was less (P<.01) in large (47.9+/-11.0%) than in small (80.7 +/-5.2%) and medium (83.4+/-4.7%) FS groups. Weaning rates of large FS first- and second-parity dams were less (P<.05) than those of small and medium FS dams. Second-parity dams with BCS 3 had lower (P<.05) WR than dams with BCS 4 and 5. Within first- and third or greater-parity dams, BWT of calves born to small FS cows were the lightest, and those born to large FS dams were the heaviest; those born to medium FS dams were intermediate (P<.05). In second-parity dams, BWT of calves of large FS dams were greater (P<.05) than those of small and medium FS dams. In first-parity dams, calves weaned by small FS cows had lower (P<.05) WWT than those weaned by higher FS cows. In the third or greater-parity group, large FS dams weaned heavier calves (P<.05) than other dams. In all parity groups of dams, calves out of large FS cows had greater ADG (P<.05) than those from small and medium FS cows. In first-parity dams, PPC was comparable between small and medium FS dams, but both tended to be greater (P<.10) than PPC of large FS dams. Small and medium FS females reached puberty at an earlier age, calved earlier, and had greater calving, survival, and weaning rates, as well as greater kilograms of calf produced per cow exposed than the large FS females. As the large FS cows matured, they seemed to have overcome the negative effects imposed by FS that were observed at younger ages. Their performance traits were generally all comparable to those of smaller cows once they had reached maturity.  相似文献   
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The clinical and pathological aspects of a neurological disease observed in 16 horses in Pará, Amazonia, Brazil, are presented. The symptoms were mainly motor incoordination, paresis of the tongue, somnolence, difficulties in apprehension, chewing and swallowing of food, as well as instability and standing with abducted members. The clinical course was subacute or chronic and in most cases was not fatal. Postmortem examination performed in one already very sick, euthanized animal, did not show significant macroscopic lesions; histopathological examination revealed slight edema and degenerative alterations of a few axons, mainly in the medulla oblongata. In all pastures where horses were affected, plenty of bamboo had been eaten, probably because of scarcity of pasture. By feeding large amounts of fresh bamboo leaves of this region, in different growing stages, to three horses (horse 1, 47 g/kg/d for 30 days; horse 2, 10 g/kg/d for 60 days; horse 3, 18 g/kg on the first day, and 31 g/kg/d for 6 more days)—the animals ate the leaves unassisted—it was possible to reproduce nervous symptoms essentially identical to those observed in the natural disease 24 to 72 hours after the first feeding of the plant. In spite of continuous administration of the plant, intensity of the clinical signs did not increase. Based on field observations and comparison of the clinical and pathological pictures seen in the natural and experimental disease, the described illness can be concluded to be caused by the ingestion of large amounts of the leaves of Bambusa vulgaris f. vulgaris.  相似文献   
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The extensive pig production in Spain is traditionally characterised by: the use of the Iberian pig, an autochthonous breed perfectly integrated into the environment in which they have developed; a long duration of the productive cycle for about 23–24 months; a high level of animal welfare level, specially in the fattening process with freedom of movement and feeding base on natural sources: acorns and grass, and an equilibrated “dehesa” agro-forestry system where this activity has been developed. Nowadays, the introduction of more intensificated methods due to the increasing demand led to important changes, such as: the shortening of the productive cycle (10–12 months); freeing from the territorial base; changes during the fattening period, fattening with mixed feed and less animal freedom. All these facts may implicate a loss of the animal welfare condition. These circumstances lead us to question it from an ethical point of view.  相似文献   
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An attempt was made to understand the molecular systematics and genetic differences between 10 original chrysanthemum cultivars and 11 mutants. The similarity among the cultivars and mutants varied from 0.17 to 0.90 using RAPD analyses, a simple but efficient method to distinguish cultivars and to assess parentage. Two distinct groups were found. Two cultivars were present as a separate group showing differences from all other cultivars. Mutants with different flower colour could be identified at the molecular level using RAPD technique holding promise to identify unique genes as SCAR markers. A high genetic distance among the different chrysanthemums showed that there exists a possibility of introgressing new and novel genes from the chrysanthemum gene pool.  相似文献   
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Santiago, Chile's semi-arid climate and urbanized environment poses a severe limitation for the establishment and maintenance of urban forests. Municipalities, or comunas, are the main stakeholders in the management of Santiago's public urban forests. A tenable hypothesis would be that as the socioeconomic level of a comuna increases, the better the condition of a comuna's urban forest. Unfortunately, there is little comprehensive information on management, public expenditure, and structure of Santiago's public and private urban forests. To examine this hypothesis, Santiago was divided into socioeconomic strata, then using air photo interpretation and stratified field sampling, urban forest structures were quantified by socioeconomic strata. In addition, interview surveys were used to determine municipal urban forest management and expenditures for different public urban forests based on socioeconomic strata. Urban forests in the high socioeconomic strata had fewer public trees, greater tree cover, tree and leaf area density, and leaf area index than lower socioeconomic strata. The percentage of total municipal budget allocated to public urban forest management was consistent among strata, but the total public urban forest budgets were greater in the high socioeconomic strata. Public urban forest structure is related to the socioeconomic strata of Santiago's different comunas.  相似文献   
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