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31.
Ectophylla alba is a tent-making bat that roosts in mixed-sex clusters comprising adults and offspring. Our goal was to determine the genetic identity of individuals belonging to different roosting groups. We tested the hypothesis of kin selection as a major force structuring group composition. We used 9 microsatellites designed for E. alba to determine the genetic identity and probability of parentage of individuals. We analyzed parentage and kinship using the software ML-Relate, GenAIEx, and Cervus. The obtained relationship probabilities (0.5) revealed a clear maternal relationship between female adults and offspring with allele compatibility, and at least 5 relationships between male adults and pups. We found a low degree of relatedness within roosting groups. Between roosting groups at different sites, the mean probability of a half-sibling relationship ranged from 0.214 to 0.244 and, for full-sibling relationship, from 0.383 to 0.553. Genetically, adult individuals were poorly related within clusters, and kinship as an evolutionary force could not explain group membership.  相似文献   
32.
OBJECTIVE: To evaluate the effectiveness of an extra-articular surgical technique using absorbable suture material for the stabilization of traumatic coxofemoral luxation in dogs. STUDY DESIGN: Prospective, clinical study. ANIMALS: Fourteen client-owned dogs with recent and long-standing traumatic coxofemoral luxation (13 craniodorsal and 1 ventral). METHODS: Coxofemoral luxations were surgically reduced and maintained in place with an extra-articular iliofemoral multifilamentous absorbable suture (3 to 6 strands of 2 USP Polyglactin 910). No external support was employed, and all the dogs were encouraged to use the affected limb postoperatively. The average time of clinical and radiographic follow-up was 11.6 +/- 6.3 months (from 2 to 22 months). RESULTS: During the follow-up period, no reluxations occurred and no complications associated with the surgical technique were identified. The dogs started bearing weight from 1 to 10 days after the surgery (mean, 4.3 +/- 2.9 days) and the period of lameness ranged from 7 to 30 days (20 +/- 8.6 days). At the final clinical examination, the dogs did not demonstrate any lameness or pain during passive flexo-extension movements, and there was no significant limitation of the range of motion. CONCLUSION: Extra-articular stabilization with multifilamentous absorbable sutures is a simple, effective method of treatment for acute and chronic coxofemoral luxation. The absorbable material used is strong enough to maintain articular stability during the period of scar tissue formation even in large-breed dogs. CLINICAL RELEVANCE: Absorbable sutures avoid the possible complications related to the use of nonabsorbable material and seem to be sufficient to maintain articular stability during the capsular healing process.  相似文献   
33.
To compare the effects of PGF2α (dinoprost tromethamine) and d-cloprostenol in a two-dose protocol for estrus synchronization in hair sheep during breeding season in Yucatán, México, two experiments were conducted. In experiment 1, 61 cyclic hair sheep were divided into two groups: G1 (control n?=?30), two doses of 50 μg of dinoprost tromethamine IM with 12 days between applications, and G2 (n?=?31), two doses of 50 μg of d-cloprostenol IM at the same time interval. For determination of progesterone levels, 16 ewes from each group were randomly selected. In experiment 2, 70 cyclic hair sheep were assigned at the same treatments (G1 and G2, n?=?35) and 48 h after the second application, the ewes in estrus were detected by two vasectomized rams. Sheep with detected estrus were inseminated, and 45 days after, pregnant animals were identified by ultrasonography. An exact Fisher’s test was performed for the analysis of ewes in estrus (experiments 1 and 2) and number of pregnant ewes (experiment 2); for the comparison of time between end of treatment-estrus presentation, a survival analysis was used. Duration of estrus in hours was analyzed using a generalized mixed model (GLM) ANOVA whereas plasma progesterone concentrations were analyzed by non-linear regression. There were significant differences (P?<?0.05) in the proportion of ewes in estrus upon treatments (G1, 57% vs G2, 87% and G1, 37.1% vs G2, 65.7% in experiments 1 and 2, respectively), and between the end of treatment-onset estrus interval (P?<?0.01), survival curves showed the highest number of sheep in estrus between 40 and 48 h (G1, 43.7?+?8.05 h vs G2, 42.9?+?6.7 h, experiment 1). There were no significant differences (P?>?0.05) in duration of estrus (G1, 42?+?6.1 h, vs G2, 41.1?+?11.2 h, experiment 1) and pregnancy in the ewes that presented estrus, and were inseminated (G1, 38.4% vs 52.1%, experiment 2). With regard to concentrations of progesterone, significant differences (P?<?0.01) were found between treatments, and progesterone levels before the second application of d-cloprostenol were higher. In consideration of the results, it can be concluded that in a two-dose protocol of a luteolytic agent, more ewes presented estrus in response to d-cloprostenol compared to dinoprost tromethamine with similar pregnancy rates.  相似文献   
34.
In this study, two populations of dogs with pituitary dependent hypercortisolism (PDH) were compared over a 2-year period. One group had normal vision (Group A, n=27) and one group was blind (Group B, n=20). Group B was characterised by the rapid appearance of the clinical signs of PDH that precede blindness. We found increases in pre-adrenocorticotropic hormone cortisol (P=0.002), IL-6 (P=0.0001), insulin, and insulin sensitivity (detected with the Homeostatic Model Assessment, P<0.0001) in Group B but not in Group A. The nitric oxide (NO) and the total adiponectin concentrations decreased (P=0.0001 and P=0.02, respectively) in Group B versus Group A. The IL-6 and insulin concentrations and the HOMA-A index were positively correlated with the cortisol concentration and were negatively correlated with the NO concentration. With the exception of adiponectin, the other variables were associated with blindness. We concluded that blindness in PDH is a haemodynamic event associated with metabolic changes, with the increase in the IL-6 concentration and the decrease in the NO concentration affecting the retinal vasculature and producing a high risk of vision loss.  相似文献   
35.
Reforestation efforts in dryland ecosystems frequently encounter drought and limited soil productivity, although both factors usually interact synergistically to worsen water stress for outplanted seedlings. Land degradation in drylands (e.g. desertification) usually reduces soil productivity and, especially, soil water availability. In dry sub-humid regions, forest fires constitute a major disturbance affecting ecosystem dynamics and reforestation planning. Climate change projections indicate an increase of drought and more severe fire regime in many dryland regions of the world. In this context, the main target of plantation technology development is to overcome transplant shock and likely adverse periods, and in drylands this is mostly related to water limitations. In this paper, we discuss some selected steps that we consider critical for improving success in outplanting woody plants, both under current and projected climate change conditions including: (1) Plant species selection, (2) Improved nursery techniques, and (3) Improved planting techniques. The number of plant species used in reforestation is increasing rapidly, moving from a reduced set of well-known, easy-to-grow, widely used species, to a large variety of promising native species. Available technologies allow for reintroducing native plants and recovering critical ecosystem functions for many degraded drylands. However, climate change projections introduce large uncertainties about the sustainability of current reforestation practices. To cope with these uncertainties, adaptive restoration approaches are suggested, on the basis of improved plant quality, improved techniques for optimizing rain use efficiency in plantations, and exploring native plant species, including provenances and genotypes, for their resilience to fire and water use efficiency.  相似文献   
36.
Two methods for the determination of dichlorvos in durum wheat by electrochemical assay and gas chromatography, respectively, have been developed. Dichlorvos, an organophosphorus anticholinesterase pesticide, was extracted from wheat with hexane, and the filtered extract was directly analyzed by gas chromatography with nitrogen-phosphorus flame detection (NPD). Recoveries of dichlorvos from milled wheat spiked at 0.25-1.5 microg/g ranged from 96.5 to 100.9%, and the limit of detection was 0.02 microg/g. The electrochemical assay was based on the detection of choline, the acetylcholinesterase product, via a choline oxidase biosensor. An aliquot of the filtered hexane extract was partitioned with phosphate buffer solution, and the organic layer was evaporated prior to electrochemical analysis. A limit of detection of 0.05 microg/g of dichlorvos was obtained with mean recoveries of 97-103% at spiking levels of 0.25-1.5 microg/g. A good correlation (r = 0.9919) was found between the results obtained with the electrochemical and those obtained with the gas chromatographic methods. The electrochemical method was peer-validated in two laboratories that analyzed 10 blind samples (5 duplicates), including a blank and 4 spiked samples with dichlorvos at levels of 0.25, 0.60, 1.00, and 1.50 microg/g. Within-laboratory repeatability (RSDr) and between-laboratory reproducibility (RSDR) ranged from 5.5 to 7.8% and from 9.9 to 17.6%, respectively.  相似文献   
37.
Over the last few decades, important advances have been made in understanding of host–parasitoid relations and their applications to biological pest control. Not only has the number of agent species increased, but new manipulation techniques for natural enemies have also been empirically introduced, particularly in greenhouse crops. This makes biocontrol more complex, requiring a new mathematical modeling approach appropriate for the optimization of the release of agents. The present paper aimed at filling this gap by the development of a temperature- and stage-dependent dynamic mathematical model of the host–parasitoid system with an improved functional response. The model is appropriate not only for simulation analysis of the efficiency of biocontrol agents, but also for the application of optimal control methodology for the optimal timing of agent releases, and for the consideration of economic implications. Based on both laboratory and greenhouse trials, the model was validated and fitted to the data of Chelonus oculator (F.) (Hym.: Braconidae) as a biological control agent against the beet armyworm, Spodoptera exigua Hübner (Lep.: Noctuidae). We emphasize that this model can be easily adapted to other interacting species involved in biological or integrated pest control with either parasitoid or predator agents.  相似文献   
38.
The chemical composition of lignin and lipids of bast fibers from kenaf (Hibiscus cannabinus) used for high-quality paper pulp production was studied. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) of fibers showed a lignin with a high syringyl/guaiacyl ratio (5.4) and minor amounts of p-hydroxyphenyl units. Simultaneously, sinapyl and coniferyl acetates were also identified, indicating that this lignin is partially acetylated. p-Hydroxycinnamic acids were found in only trace amounts. The main lipids identified by GC/MS of extracts from kenaf fibers were series of long-chain n-fatty acids, waxes, n-alkanes, and n-fatty alcohols. Free and esterified sterols and triterpenols, steroid hydrocarbons, and steroid and triterpenoid ketones, as well as steryl glycosides, were also found. Finally, the fate of the main constituents of kenaf fibers in alkaline pulping was also investigated.  相似文献   
39.
40.
The majority of studies on the immunobiology of Trichinella species have centred on the larval muscular phase (L1) with a view to identifying immunodominant antigens located on the surface of the cuticle and in the larval secretions; the nucleus of the parasite-host interaction. These antigens have been classified as eight groups (TSL-1-TSL-8), of which those belonging to the group TSL-1 have been most intensely studied. The principal constituents are glycoproteins, glycan carriers that contain a unusual sugar, the tyvelose (3,6-dideoxy-d-arabinohexose). Studies aimed at improving serodiagnostic techniques to detect trichinellosis indicate that these antigens are ideal candidates. They are capable of inducing a strong humoral response involving the generation of specific antibodies against beta-tyvelose, a sugar that seems to be exclusive to the Trichuroidea. Furthermore, these glycoproteins appear to fulfil an important function in the development and maintenance of the parasite in the muscular niche, and they appear to be fundamental for the invasion of the intestinal epithelium. It has also been demonstrated that specific monoclonal antibodies against tyvelose can mediate a degree of immunoprotection in the rat through the phenomenon known as rapid expulsion.  相似文献   
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