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21.
Aggression when pigs are mixed into new social groups has negative impacts on welfare and production. Aggressive behaviour is moderately heritable and could be reduced by genetic selection. The possible wider impacts of selection for reduced aggressiveness on handling traits and activity in the home pen were investigated using 1663 male and female pedigree pigs (898 purebred Yorkshire and 765 Yorkshire × Landrace). Aggressive behaviour was observed over 24 h after pigs were mixed at 10 weeks of age into groups balanced for unfamiliarity and weight. Aggression was highly heritable (duration of involvement in reciprocal fighting h2 = 0.47 ± 0.03, and duration of delivering one-sided aggression h2 = 0.34 ± 0.03). Three weeks after mixing, home pen inactivity (indicated by the frequency of lying) was observed over 24 h. Inactivity was weakly heritable (h2 = 0.05 ± 0.01) but showed no significant genetic association with aggression. Pigs' behaviour during handling by humans was assessed on entry to, whilst inside and on exit from a weigh crate at both mixing and end of test at 22 weeks. Pigs were generally easy to handle, moving easily into and out of the crate. Scores indicating 'very difficult to move' were rare. Handling scores at weighing were weakly heritable (h2 = 0.03 to 0.17), and moderately correlated across the two weighings (rg = 0.28 to 0.76). Aggressive behaviour at mixing was genetically associated with handling at the end of test weighing: pigs that fought and delivered one-sided aggression had handling scores indicating more active behaviour at weighing (e.g. moving quickly into the crate v. fighting rg = 0.41 ± 0.05 and v. bullying rg = 0.60 ± 0.04). Also, there was a genetic association between receiving one-side aggression at mixing and producing high-pitched vocalisations in the weigh crate (rg = 0.78 ± 0.08). Correlated behavioural responses occurring across different challenging situations (e.g. social mixing and human handling) have been described by the concept of animal temperament (also known as coping styles, personality or behavioural syndromes), but this has rarely been demonstrated at the genetic level in farm animals. These findings may have practical implications for the development of breeding programmes aimed at altering animal temperament. Breeding to reduce aggression could result in some reduction in activity at weighing. This would have consequences for animal production, because pigs which are inactive at weighing take longer to move into and out of the weigh crate, and perhaps also for animal welfare.  相似文献   
22.

Introduction  

There is an ever-increasing need for animal models to evaluate efficacy and safety of new therapeutics in the field of rheumatoid arthritis (RA). Particularly for the early preclinical evaluation of human-specific biologicals targeting the progressive phase of the disease, there is a need for relevant animal models. In response to this requirement we set out to develop a model of collagen-induced arthritis (CIA) in a small-sized nonhuman primate species (300 to 400 g at adult age); that is, the common marmoset (Callithrix jacchus).  相似文献   
23.
Over 3500 patients with recent onset inflammatory polyarthritis (IP) have been recruited by the Norfolk Arthritis Register (NOAR) since 1990. Longitudinal data from this cohort have been used to examine the prevalence and predictors of remission, functional disability, radiological outcome, cardiovascular mortality and co-morbidity and the development of non-Hodgkin's lymphoma. Rheumatoid factor titre, high baseline C-reactive protein and high baseline HAQ score are all predictors of a poor outcome. There is a strong association between possession of the shared epitope and the development of erosions. Patients who satisfy the American College of Rheumatology criteria for rheumatoid arthritis (RA) have a worse prognosis than those who do not. However, it appears that these patients are a poorly defined subset of all those with IP rather than having an entirely separate disease entity. New statistical techniques offer exciting possibilities for using longitudinal datasets such as NOAR to explore the long-term effects of treatment in IP and RA.  相似文献   
24.
Nucleotide sequences from two nuclear loci, alcohol dehydrogenase and internal transcribed spacer-1 of the nuclear ribosomal DNA repeats, and two mitochondrial genes, cytochrome oxidase I and cytochrome oxidase II, were determined from nine species in the Drosophila saltans species group. The partition homogeneity test and partitioned Bremer support were used to measure incongruence between phylogenetic hypotheses generated from individual partitions. Individual loci were generally congruent with each other and consistent with the previously proposed morphological hypothesis, although they differed in level of resolution. Since extreme conflict between partitions did not exist, the data were combined and analyzed simultaneously. The total evidence method gave a more resolved and highly supported phylogeny, as indicated by bootstrap proportions and decay indices, than did any of the individual analyses. The cordata and elliptica subgroups, considered to have diverged early in the history of the D. saltans group, were sister taxa to the remainder of the saltans group. The sturtevanti subgroup, represented by D. milleri and D. sturtevanti, occupies an intermediate position in this phylogeny. The saltans and parasaltans subgroups are sister clades and occupy the most recently derived portion of the phylogeny. As with previous morphological studies, phylogenetic relationships within the saltans subgroup were not satisfactorily resolved by the molecular data.   相似文献   
25.
Bovine herpesviruses 1 and 5 (BoHV-1 and BoHV-5) are economically important pathogens, associated with a variety of clinical syndromes, including respiratory and genital disease, reproductive failure and meningoencephalitis. The standard serological assay to diagnose BoHV-1 and BoHV-5 infections is the virus neutralization test (VNT), a time consuming procedure that requires manipulation of infectious virus. In the present study a highly sensitive and specific single dilution indirect ELISA was developed using recombinant glycoprotein D from BoHV-5 as antigen (rgD5ELISA). Bovine serum samples (n = 450) were screened by VNT against BoHV-5a and by rgD5ELISA. Compared with the VNT, the rgD5ELISA demonstrated accuracy of 99.8%, with 100% sensitivity, 96.7% specificity and coefficient of agreement between the tests of 0.954. The rgD5ELISA described here shows excellent agreement with the VNT and is shown to be a simple, convenient, specific and highly sensitive virus-free assay for detection of serum antibodies to BoHV-5.  相似文献   
26.
The localisation of the vacuolar proton pump (V-H+ -ATPase) and the enzyme carbonic anhydrase II (CAII) was investigated in the human eccrine sweat gland employing standard immunohistochemical techniques after antigen retrieval using microwave heat treatment and high pressure. The high-pressure antigen retrieval unmasked the presence of V-H+ -ATPase in the clear cells of the secretory coil, with a distribution similar to that previously observed for CAII. However, the dark cells were unreactive to both antibodies. In addition, heat and high-pressure antigen retrieval demonstrated the presence of CAII in the apical zone of luminal cells of the reabsorptive duct, a location not previously reported. The localisation of V-H+ -ATPase and CAII in the secretory coil clear cells suggests that the formation of HCO3- and H+ by carbonic anhydrase II and the transport of H+ by V-H+ -ATPase may play an role in sweat fluid secretion. Their presence at the apex of the duct cells indicates involvement in ductal ion reabsorption.  相似文献   
27.

Background

Venous thromboembolism (VTE) is a common preventable cause of mortality in hospitalized medical patients. Despite rigorous randomized trials generating strong recommendations for anticoagulant use to prevent VTE, nearly 40% of medical patients receive inappropriate thromboprophylaxis. Knowledge-translation strategies are needed to bridge this gap.

Methods

We conducted a 16-week pilot cluster randomized controlled trial (RCT) to determine the proportion of medical patients that were appropriately managed for thromboprophylaxis (according to the American College of Chest Physician guidelines) within 24 hours of admission, through the use of a multicomponent knowledge-translation intervention. Our primary goal was to determine the feasibility of conducting this study on a larger scale. The intervention comprised clinician education, a paper-based VTE risk assessment algorithm, printed physicians’ orders, and audit and feedback sessions. Medical wards at six hospitals (representing clusters) in Ontario, Canada were included; three were randomized to the multicomponent intervention and three to usual care (i.e., no active strategies for thromboprophylaxis in place). Blinding was not used.

Results

A total of 2,611 patients (1,154 in the intervention and 1,457 in the control group) were eligible and included in the analysis. This multicomponent intervention did not lead to a significant difference in appropriate VTE prophylaxis rates between intervention and control hospitals (appropriate management rate odds ratio = 0.80; 95% confidence interval: 0.50, 1.28; p = 0.36; intra-class correlation coefficient: 0.022), and thus was not considered feasible. Major barriers to effective knowledge translation were poor attendance by clinical staff at education and feedback sessions, difficulty locating preprinted orders, and lack of involvement by clinical and administrative leaders. We identified several factors that may increase uptake of a VTE prophylaxis strategy, including local champions, support from clinical and administrative leaders, mandatory use, and a simple, clinically relevant risk assessment tool.

Conclusions

Hospitals allocated to our multicomponent intervention did not have a higher rate of medical inpatients appropriately managed for thromboprophylaxis than did hospitals that were not allocated to this strategy.  相似文献   
28.
Detection of bovine herpesvirus 1 and 5 in semen from Brazilian bulls   总被引:1,自引:0,他引:1  
Bovine herpesvirus 1 (BoHV-1) and 5 (BoHV-5) are important pathogens of the respiratory and genital tract of cattle and may also affect the central nervous system and cause meningoencephalitis. Both virus types are estimated to be widely distributed in Southern Brazil. In the present study, BoHV-1 and/or BoHV-5 DNA were detected in bovine semen samples from two states of Brazil by two species-specific nested polymerase chain reactions (nPCRs). These nPCRs were used to assay 53 samples of fresh semen and 23 samples of frozen semen from breeding bulls. Viral DNA was detected in all 76 semen samples: all were positive for BoHV-5, whereas 34 of these were positive for BoHV-1 as well. Moreover, in five fresh and in 13 frozen semen samples—of a total number of 40 samples suitable for virus isolation—infectious BoHV-1 and/or BoHV-5 virus were detected. In conclusion, that both BoHV-1 and BoHV-5 were detected in bovine semen in Brazil highlighted the importance of examining bull semen in search for both agents to reduce the risk of transmitting these viruses.  相似文献   
29.
Pollinator declines have raised concerns about the persistence of plant species that depend on insect pollination, in particular by bees, for their reproduction. The impact of pollinator declines remains unknown for species‐rich plant communities found in temperate seminatural grasslands. We investigated effects of land‐use intensity in the surrounding landscape on the distribution of plant traits related to insect pollination in 239 European seminatural grasslands. Increasing arable land use in the surrounding landscape consistently reduced the density of plants depending on bee and insect pollination. Similarly, the relative abundance of bee‐pollination‐dependent plants increased with higher proportions of non‐arable agricultural land (e.g. permanent grassland). This was paralleled by an overall increase in bee abundance and diversity. By isolating the impact of the surrounding landscape from effects of local habitat quality, we show for the first time that grassland plants dependent on insect pollination are particularly susceptible to increasing land‐use intensity in the landscape.  相似文献   
30.
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