Inoculation of swine with a sylvatic isolate of Trichinella spiralis, designated T s nativa, resulted in low numbers of muscle larvae, compared with muscle larvae accumulation in swine inoculated with a pig type of T s spiralis. Despite low infectivity of T s nativa for swine, primary inoculation resulted in high levels of immunity against challenge infection with T s spiralis. This immunity was expressed in accelerated expulsion of challenge adults from the intestine and reduced numbers of muscle larvae. Pigs inoculated with T s nativa developed cellular and humoral responses similar to those in pigs inoculated with T s spiralis. However, in immunoblots, sera from pigs inoculated with T s nativa recognized additional proteins in muscle larvae excretory-secretory (ES) products, compared with sera from pigs inoculated with T s spiralis. Active immunization of pigs with ES products from T s nativa resulted in numerically higher, but not significantly different levels of immunity, compared with pigs immunized with ES from T s spiralis. The highest levels of immunity were obtained in pigs immunized with a T s spiralis newborn larval extract. The combination of ES products and newborn larval extract did not result in additive levels of immunity. These results indicate that the major immune effector response to Trichinella sp in pigs is against the newborn larvae, regardless of the genetic type of Trichinella sp. 相似文献
The determination of genetic variability by means of molecular genetic markers FUT1 and ESR2, and the evaluation of their associations with reproduction traits in population of P?e?tice Black‐Pied sows have been implemented. A lower frequency of the allele FUT1A than the frequency of the allele FUT1G in the FUT1 gene was ascertained. In the ESR2 polymorphism, a higher frequency of the allele ESR2A compared with the allele ESR2B was determined. In the second to sixth litters as well as in the first to sixth litters, a significantly lower number of piglets born alive and number of weaned piglets from sows of the FUT1A/FUT1A genotype was found. Moreover, the homozygotes FUT1G/FUT1G significantly exceeded sows of the FUT1A/FUT1A genotype in the total number of born piglets in the first to sixth litters. No significant effect of the ESR2 polymorphism on reproduction was observed. 相似文献
NREP (neuronal regeneration related protein homolog) plays a role in the transformation of neural, muscle, and fibroblast cells and in smooth muscle myogenesis. The NREP gene was selected for detailed study as an expressional and functional candidate gene on the basis of data from the expression microarray, which detected the differences in gene expression between Czech Large White pigs and wild boars in the longissimus lumborum et thoracis and biceps femoris muscle tissues. Quantitative real-time PCR results confirmed that porcine NREP was expressed in both skeletal muscles and significantly overexpressed in Czech Large White pigs compared with wild boars (14.5- and 11.6-fold; p < .05). We identified 9 polymorphic sites in the genomic DNA of NREP. Six of these polymorphisms were in complete linkage disequilibrium, and therefore, only 4 loci were informative. The associations of the HF571253:g.103G>A, HF571253:g.134G>A, HF571253:g.179T>C and HF571253:g.402_409delT polymorphisms with backfat thickness, lean meat content and average daily gain were assessed in Czech Large White pigs. The GG genotypes HF571253:g.103G>A and HF571253:g.134G>A, the TT genotypes HF571253:g.179T>C and 67 HF571253:g.402_409delT genotypes had favourable effects on the studied traits. Our results indicate the possibility of utilizing the variability of the NREP gene in marker-assisted selection in order to improve meat production in pigs. 相似文献
A main symptom of equine metabolic syndrome (EMS) in ponies is pathological obesity characterized by abnormal accumulation of fat deposits and inflammation. In this study, we analyzed the expression of two pro-inflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), in subcutaneous adipose tissue and the correlation with serum concentrations in peripheral blood of Welsh ponies. Based on clinical examination findings, the animals were divided into two groups: ponies affected with EMS (n = 8) and obese ponies (n = 8). The adipose tissue was examined using immunohistochemical analysis while concentrations IL-6 and TNF-α were measured using enzyme-linked immunosorbent assays (ELISAs). Additionally, histological characterization of the adipose tissue was performed. The results obtained showed that IL-6 expression in adipose tissue biopsies derived from animals with EMS was enhanced while TNF-α levels of both groups were comparable. Compared to the obese ponies, EMS animals also had significantly elevated levels of serum IL-6 and TNF-α. Histological analysis revealed macrophage infiltration and fibrosis in adipose tissue preparations from the EMS group. These data suggest that IL-6 may play a key role in the course of EMS in Welsh ponies. Our findings also demonstrated that analysis of pro-inflammatory cytokines levels in serum may serve as an additional tool for diagnosing EMS. 相似文献
The monthly water balance in gaps in a managed Dinaric silver fir–beech forest and a virgin forest remnant located in SE Slovenia
was modelled using a capacity water balance model for two growing seasons. Two gaps of different size (ca. 0.07 and 0.15 ha)
were selected in each forest and plots for soil moisture monitoring were established in each gap (2–4) and in the surrounding
forest (2–3). We report on the modelled actual evapotranspiration (AET) and potential evapotranspiration (PET) and drainage
fluxes (DF) from the rooting zone at the plots. Precipitation over the 2001 growing season (May–October) was considerably
drier than average and that for 2002 growing season was wetter than average. Modelled AET for the 2001 growing season varied
between 88% and 96% of PET for the managed forest plots and between 90% and 100% for the virgin forest plots. The values for
the gap plots varied between 87% and 100% at the managed forest site and between 92% and 96% for the gaps in the virgin forest
site. Monthly AET values declined to 57–59% of PET at plots in the centre of the gaps in the managed forest site and to 63–74%
in the gaps in the virgin forest site (July), indicating that the highest drought stress occurs in gap centres. For 2002 growing
season, AET for all plots was 100% of PET. Modelled DF values in 2001 were 13–35% of rainfall for plots in the gap centres
and 12–16% for plots in the forest at the managed forest site. On an average, gap DF values were 20% (154 mm) higher than
the forest plot values. DF values in 2002 were similar for all plots at the managed forest site, 31–33% of rainfall. At the
virgin forest site, 2001 growing season, DF values varied between 12% and 30% of rainfall at the forest plots and between
12% and 32% at the gap plots. In 2002, DF values for all plots in the virgin forest site varied between 24% and 38% of growing
season rainfall. The varying development of vegetation and forest in the gaps of the virgin forest remnant resulted in more
variable evapotranspiration and DF during the drought year 2001, with values not as clearly related to distance from the gap
centre as in the managed forest site. 相似文献
T helper (Th) cells produce signature cytokine patterns, induced largely by intracellular versus extracellular pathogens that provide the cellular and molecular basis for counter regulatory expression of protective immunity during concurrent infections. The production of IL-12 and IFN-γ, for example, resulting from exposure to many bacterial, viral, and protozoan pathogens is responsible for Th1-derived protective responses that also can inhibit development of Th2-cells expressing IL-4-dependent immunity to extracellular helminth parasites and vice versa. In a similar manner, concurrent helminth infection alters optimal vaccine-induced responses in humans and livestock; however, the consequences of this condition have not been adequately studied especially in the context of a challenge infection following vaccination. Demands for new and effective vaccines to control chronic and emerging diseases, and the need for rapid deployment of vaccines for bio security concerns requires a systematic evaluation of confounding factors that limit vaccine efficacy. One common albeit overlooked confounder is the presence of gastrointestinal nematode parasites in populations of humans and livestock targeted for vaccination. This is particularly important in areas of the world were helminth infections are prevalent, but the interplay between parasites and emerging diseases that can be transmitted worldwide make this a global issue. In addition, it is not clear if the epidemic in allergic disease in industrialized countries substitutes for geohelminth infection to interfere with effective vaccination regimens. This presentation will focus on recent vaccination studies in mice experimentally infected with Heligmosomoides polygyrus to model the condition of gastrointestinal parasite infestation in mammalian populations targeted for vaccination. In addition, a large animal vaccination and challenge model against Mycoplasma hyopneumonia in swine exposed to Ascaris suum will provide a specific example of the need for further work in this area, and for controlled field studies to assess the impact of other similar scenarios. 相似文献
Quantitative grouping of similar landscape patterns is an important part of landscape ecology due to the relationship between a pattern and an underlying ecological process. One of the priorities in landscape ecology is a development of the theoretically consistent framework for quantifying, ordering and classifying landscape patterns.
Objective
To demonstrate that the information theory as applied to a bivariate random variable provides a consistent framework for quantifying, ordering, and classifying landscape patterns.
Methods
After presenting information theory in the context of landscapes, information-theoretical metrics were calculated for an exemplar set of landscapes embodying all feasible configurations of land cover patterns. Sequences and 2D parametrization of patterns in this set were performed to demonstrate the feasibility of information theory for the analysis of landscape patterns.
Results
Universal classification of landscape into pattern configuration types was achieved by transforming landscapes into a 2D space of weakly correlated information-theoretical metrics. An ordering of landscapes by any single metric cannot produce a sequence of continuously changing patterns. In real-life patterns, diversity induces complexity—increasingly diverse patterns are increasingly complex.
Conclusions
Information theory provides a consistent, theory-based framework for the analysis of landscape patterns. Information-theoretical parametrization of landscapes offers a method for their classification.
Graph-theoretic evaluations of habitat connectivity often rely upon least-cost path analyses to evaluate connectedness of habitat patches, based on an underlying cost surface. We present two improvements upon these methods.
Objectives
As a case study to test these methods, we evaluated habitat connectivity for the endangered San Martin titi monkey (Plecturocebus oenanthe) in north-central Peru, to prioritize habitat patches for conservation.
Methods
First, rather than using a single least-cost path between habitat patches, we analyzed multigraphs made up of multiple low-cost paths. This allows us to differentiate between patches connected through a single narrow corridor, and patches connected by a wide swath of traversable land. We evaluate potential movement pathways by iteratively removing paths and recomputing connectivity metrics. Second, instead of performing a sensitivity analysis by varying costs uniformly across the landscape, we generated landscapes with spatially varying costs.
Results
This approach produced a more informative assessment of connectivity than standard graph analyses. Of the 4340 habitat patches considered across the landscape, we identified the most important 100, those frequently ranked highly through repeated network modifications, for multiple metrics and cost surfaces.
Conclusions
These methods represent a novel approach for assessing connectivity, better accounting for spatial configurations of habitat patches and uncertainty in cost surfaces. The ability to identify habitat patches with more possible routes to other patches is of interest for resiliency planning and prioritization in the face of continued habitat loss and climate change. These methods should be broadly applicable to conservation planning for other wildlife species.