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711.
The spatial behaviour of 10 Southern river otters Lontra provocax was analysed using radio-tracking data collected in the Queule River, Southern Chile. The estimated otter density was 0.25 individuals km−1. Females with cubs and adult otters displaying mating behaviours were the only social group recorded. Studied otters were solitary and observed behaviour patterns suggest an intrasexual territoriality. No home range overlap among males existed while an average of 33% and 87% home range overlapped among females and between sexes, respectively. In the situation of core areas, only one case of overlapping between an adult male and an adult female was observed. Average home range and core area lengths were 11.3 km and 0.9 km, respectively. Otters used rivers more frequently than expected, whereas they avoided small streams. Low intensity livestock farming, without canalization of watercourses and riparian vegetation extraction practices, seems compatible with the presence of Southern river otter populations since the spatial behaviour of the studied otters was not affected under these circumstances. Based on the present official reserve sizes and distribution within the country, and also the increase of variant anthropogenic land uses outside these areas that result with consequent habitat loss and deterioration, we strongly recommend considering the importance of spatial dimension in quantity and quality habitats in further conservation planning for the Southern river otter using an integrated catchment management.  相似文献   
712.
713.
Field trials were carried out on the use of swamp buffaloes (2n = 48) as recipients of in vitro-derived vitrified river buffalo (2n = 50) embryos. River buffalo embryos were produced through a total in vitro production system using frozen semen from a top progeny-tested bull and slaughter-house-derived ovaries and cryopreserved by a vitrification technique. Recipient swamp buffaloes were Philippine carabaos selected on body condition, parity, and reproductive status and owned by village farmers. Eighty post-warmed riverine embryos were transferred non-surgically to 40 swamp buffalo recipients, of which three healthy riverine calves were born by normal delivery and one stillbirth, representing a 5.0% (4/80) full-term development and 10% (4/40) calving rate with 75% (3/4) normal and 25% (1/4) stillbirth. The results demonstrate that, under field conditions and despite the difference in chromosome number between the embryo and recipient, swamp buffaloes are potential surrogate mothers of imported, genetically superior river buffalo frozen embryos. Thus, embryo IVP-vitrification and transfer technology is a potential tool in the propagation of genetically superior buffaloes. Precautionary measures, however, are recommended to avoid dystocia and stillbirth.  相似文献   
714.
Outbreaks of tetanus, in which 297 beef cattle and 50 sheep were affected and died, were associated with the injection of a Clostridium tetani-contaminated anthelmintic (disophenol). The disease was observed on five farms in Rio Grande Sul, Brazil.  相似文献   
715.
Captive parrots show a high incidence of obesity and other metabolic disorders due to the consumption of unbalanced diets. Therefore, this study evaluated the digestibility and metabolic effects of transitioning blue‐fronted amazons from a high fat diet (sunflower seeds) to processed diets with three degrees of starch gelatinization (SG). The same feed formulation was processed to obtain pelletized feed (PEL) at 27.1% SG; low‐cooked extruded feed (EXTL) at 81.6% SG; and high‐cooked extruded feed (EXTH) at 98.5% SG. Thirty adult parrots were fed sunflower seeds for 90 days, then were distributed in a completely randomized design with 10 repetitions per treatment, and fed one of the three prepared diets for 160 days. Feed palatability, apparent digestibility, excreta concentrations of volatile fatty acids, lactate and ammonia, initial and final radiographic examinations, blood cell counts and glucose, triglycerides, cholesterol, total protein, albumin, aspartate aminotransferase (AST) and uric acid levels were evaluated. The data were analysed by an analysis of variance and compared by Tukey's test (p < 0.05). Sunflower seed was more digestible than processed feeds (p < 0.05). Diet processing interfered with fat and starch digestibility (p < 0.001), being higher in the PEL than in the EXTH and EXTL respectively. Transitioning from sunflower seeds to balanced diets reduced serum glucose, triglycerides, cholesterol and AST (p < 0.05) and increased red blood cell, haemoglobin, lymphocyte, monocyte and leucocyte counts (p < 0.01). Radiographs indicated a decreased hourglass (p = 0.015) and a reduced heart‐liver ratio after ingesting the processed feeds (p < 0.05). Feed processing did not affect blood cell counts, serum biochemistry or radiographic examinations. In conclusion, parrots preferred the extruded diet and did not require an extensive SG to properly digest the feed. Consuming the processed diets improved the birds’ metabolism and health.  相似文献   
716.
Xanthomonas campestris pathovars are widely distributed throughout the globe and have a broad host range, causing severe economic losses in the food and ornamental crucifers markets. Using an approach based on multilocus sequence typing, phylogenetic diversity and population structure of a set of 75 Portuguese and other Xanthomonas campestris isolates from several cruciferous hosts were assessed. Although this population displayed a major clonal structure, neighbour‐net phylogenetic analysis highlighted the presence of recombinational events that may have driven the ecological specialization of X. campestris with different host ranges within the Brassicaceae family. A high level of genetic diversity within and among X. campestris pathovars was also revealed, through the establishment of 46 sequence types (STs). This approach provided a snapshot of the global X. campestris population structure in cruciferous host plants, correlating the existing pathovars with three distinct genetic lineages. Phylogenetic relationships between the founder genotype and remaining isolates that constitute the X. campestris pv. campestris population were further clarified using goeBURST algorithm. Identification of an intermediate link between X. campestris pv. campestris and X. campestris pv. raphani provided new insights into the mechanisms driving the differentiation of both pathovars. Wide geographic distribution of allelic variants suggests that evolution of X. campestris as a seedborne pathogen was not shaped by natural barriers. However, as Portuguese isolates encompass 26 unique STs and this country is an important centre of domestication of Brassica oleracea crops, a strong case is made for its role as a diversification reservoir, most probably through host–pathogen coevolution.  相似文献   
717.
Multisystemic eosinophilic epitheliotropic disease was diagnosed histologically in a 17-year-old Quarter Horse intact mare that was presented with a chronic history of respiratory distress. At necropsy, the lungs were poorly collapsed and the pulmonary parenchyma contained innumerable, discrete, spherical nodules in a miliary pattern. A few similar nodules were scattered in the liver and the renal lymph nodes. Histologically, these nodules consisted of fibrosing eosinophilic granulomas. Based on histologic findings and the absence of an etiologic agent, a diagnosis of multisystemic eosinophilic epitheliotropic disease was made.  相似文献   
718.
After 44 years of epidemiological silence, bluetongue virus (BTV) was reintroduced in Portugal in the autumn of 2004. The first clinical cases of bluetongue disease (BT) were notified in sheep farms located in the South of Portugal, close to the Spanish border. A total of six BTV, five of serotype 4 and one of serotype 2 were isolated from sheep and cattle during the 2004-2006 epizootics. The nucleotide sequence of gene segments L2, S7 and S10 of BTV-4 prototype strain (BTV4/22045/PT04) obtained from the initial outbreak and of BTV-2 (BTV2/26629/PT05) was fully determined and compared with those from other parts of the world. The phylogenetic analysis revealed that BTV4/22045/PT04 is related to other BTV-4 strains that circulate in the Mediterranean basin since 1998, showing the highest identity (99%) with BTV-4 isolates of 2003 from Sardinia and Corsica, whereas BTV2/26629/PT05 is almost indistinguishable from the Onderstepoort BTV-2 live-attenuated vaccine strain and its related field strain isolated in Italy. Since live-attenuated BTV-2 vaccine was never used in Portugal, the isolation of this strain may represent a natural circulation of the vaccine virus used in other countries in Mediterranean Europe.  相似文献   
719.
The aim of this study was to evaluate the genotoxic and mutagenic potential of contaminated soil diluted in acidic solutions and not acidic, in the offspring of rats exposed during pregnancy and neonatal periods. To this end, a comet assay and micronucleus test were performed. Soil samples were solubilized in the following three solvents: distilled water (control group), acid solvent at pH 5.2, and acid solvent at pH 3.6. Soil and solvent were mixed in a rate of 1:2 in g/mL, and hydrofluoric acid was used in the acid solvents. In the comet assay, the tail length, percentage of DNA within the tail and tail moment was analyzed in the whole blood of the pups that were studied. The number of micronuclei found in the bone marrow cells was counted in the micronucleus test. In all parameters evaluated in the comet assay, the group exposed to the lowest pH value when associated with contaminated soil (p < 0.05) had the most damage. However, the micronucleus test showed differences between all exposed groups and the control group (p < 0.05). These results reaffirm the health risks related to the exposure to soil contaminants.  相似文献   
720.
A study was made of the effect of high-pressure processing (HPP) and thermal treatment (TT) on plant bioactive compounds (tocopherols, carotenoids, and ascorbic acid) in 12 fruit juice-milk beverages and of how the food matrix [whole milk (JW), skimmed milk (JS), and soy milk (JSy)] modulates their bioaccessibility (%). HPP (400 MPa/40 °C/5 min) produced a significant decrease in carotenoid and ascorbic acid bioaccessibility in all three beverages and maintained the bioaccessibility of tocopherols in JW and JS while decreasing it in JSy. TT (90 °C/30 s) produced a significant decrease in tocopherol and carotenoid bioaccessibility in all three beverages and increased the bioaccessibility of ascorbic acid. With regard to the food matrix, α-tocopherol and ascorbic acid bioaccessibility was greatest in JW beverages and lowest in JSy beverages, whereas no significant differences were found among the three beverages in terms of carotenoid bioaccessibility. HPP-treated samples showed higher tocopherol and carotenoid bioaccessibility than TT-treated samples, thus indicating that HPP combined with a milk matrix positively modulates the bioaccessibility of certain types of bioactive components of food, mainly those of a lipophilic nature.  相似文献   
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