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The main purpose of the present study was to investigate the occurrence of antibodies against T. gondii and N. caninum in captive maned wolves from Brazil, considering that little information is available at the literature about infections by these parasites in this wild animal. Serum samples were obtained from 59 maned wolves originated from six zoos and from one ecological reserve of the southeastern and midwestern regions of Brazil. To detect IgG antibodies against T. gondii, an ELISA protocol was used and the results were expressed as ELISA reactivity indexes (EI). Serology for N. caninum was carried out by indirect fluorescent antibody test (IFAT) and cut-off titers were established at 1:25 dilution. From the total of the analyzed samples, 44 (74.6%) were seropositive for T. gondii and only 5 (8.5%) for N. caninum. Seropositivity for T. gondii ranged from 0 to 100% in the seven different origin locals, with rates over 50% among the six zoos, whereas no positivity was found in the samples from ecological reserve. For N. caninum, seroprevalence varied from 0 to 50% in the different locals, with the highest rates also detected in zoos. Seroprevalence for T. gondii was strongly related with age, with rates significantly higher among adult wolves (91.7%) when compared to newborn or young animals. Seropositive samples for N. caninum were found predominantly in adult wolves. For both parasites, seroprevalence did not show a significant distinction in relation to gender. Although seroprevalence for T. gondii was significantly higher when compared to N. caninum in the Brazilian captive maned wolves tested, these findings reflect the great exposure of this species to T. gondii and, in lower extension, to N. caninum. Also, the present study demonstrated for the first time the presence of antibodies to N. caninum in wild life from South America.  相似文献   
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  • 1. The relentless increase in both human activities and exploitation of marine resources is a threat to marine habitats and species.
  • 2. For marine systems, several protection initiatives have been outlined over the past decade to significantly reduce the current rate of biodiversity loss at global, regional, and national levels, and to establish representative networks of marine protected areas with the aim of protecting 10–30% of marine habitats.
  • 3. Reliable estimates of the total area occupied by each habitat are crucial to set adequate protection initiatives. Habitat mapping requires a sound habitat classification. Many classification schemes have been developed in different areas of the world, sometimes based on questionable criteria.
  • 4. A critical analysis of the most recent marine habitat classification list produced for the Mediterranean Sea from the Regional Activity Centre for Specially Protected Areas (RAC/SPA) showed that (i) 39% of habitats and associated species considered in the list are scarcely covered by scientific knowledge from Web‐based resources; (ii) 62% of the species/genera included in the list are primary producers; (iii) quantitative information about the geographical distribution of selected habitats and associated species is scant; and (iv) when available, information is largely unbalanced and biased towards the shallow western Mediterranean Sea.
  • 5. Improved inventories of marine habitats are needed to support accurate and consistent mapping activities. The combination of large‐scale mapping and sound habitat classifications will allow better estimates of biodiversity distribution, to reverse regional/global habitat loss rates through the achievement of conservation targets and deadlines that, for the moment, are systematically not met. Copyright © 2011 John Wiley & Sons, Ltd.
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Objective The present study investigated the foot health of the Kaimanawa feral horse population and tested the hypotheses that horses would have a large range of foot morphology and that the incidence of foot abnormality would be significantly high. Procedures Abnormality was defined as a variation from what the two veterinarian assessors considered as optimal morphology and which was considered to impact negatively on the structure and/or function of the foot. Fifteen morphometric variables were measured on four calibrated photographic views of all four feet of 20 adult Kaimanawa feral horses. Four morphometric variables were measured from the lateromedial radiographs of the left forefoot of each horse. In addition, the study identified the incidence of gross abnormality observed on the photographs and radiographs of all 80 feet. Results There was a large variation between horses in the morphometric dimensions, indicating an inconsistent foot type. Mean hoof variables were outside the normal range recommended by veterinarians and hoof care providers; 35% of all feet had a long toe conformation and 15% had a mediolateral imbalance. Abnormalities included lateral (85% of horses) and dorsal (90% of horses) wall flares, presence of laminar rings (80% of horses) and bull-nose tip of the distal phalanx (75% of horses). Both hypotheses were therefore accepted. Conclusions The Kaimanawa feral horse population demonstrated a broad range of foot abnormalities and we propose that one reason for the questionable foot health and conformation is lack of abrasive wearing by the environment. In comparison with other feral horse populations in Australia and America there may be less pressure on the natural selection of the foot of the Kaimanawa horses by the forgiving environment of the Kaimanawa Ranges. Contrary to popular belief, the feral horse foot type should not be used as an ideal model for the domestic horse foot.  相似文献   
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Lantana camara L, widely used in folk medicine, presents toxicity for farm animals. The acute poisoning effects of the apolar and polar L. camara L. extracts in mice were done. The percentage of death during 7 days after treatment, the acute signs of toxicity as well as the general activity observed in open field were assessed. The extracts were administered by i.p. route at 1.5, 3.0 and 5.0 g/kg. Animals were evaluated during the first 2 h after the treatments to assess the acute signs of toxicity and daily observations were done for the presence of death. In the end of the experiment, at day 7, or immediately after death the animals had their organs removed, weighted and observed for macroscopic alterations. 1H NMR and TLC analysis suggest the presence of triterpenoids in the apolar phase but not in the polar phase. Results showed also that both extracts produced similar percentage of death, mainly after 2 days of treatment; only the apolar extract presented a dose-dependent increased lethality. At necropsy, mice treated by both apolar and polar extracts were severely icteric, dehydrated and constipated, with hepatosis, showed congested heart and lung, and nephrosis; no skin lesions were shown. The main signs of toxicity revealed a decreased spontaneous general activity. In addition, it was observed a decreased duration of locomotion and animal rearing parallel to an increased immobility in the open field. The similarity of the signs related to the acute toxicity for both apolar and polar extracts suggested that the extracts have some of the active toxic principles in common. Data from open field behavior and spontaneous signs of toxicity suggest that the toxic principles have depressive properties on central nervous system.  相似文献   
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