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Consistent individual differences in behaviour are widespread in animals, but the proximate mechanisms driving these differences remain largely unresolved. Parasitism and immune challenges are hypothesized to shape the expression of animal personality traits, but few studies have examined the influence of neonatal immune status on the development of adult personality. We examined how non-pathogenic immune challenges, administered at different stages of development, affected two common measures of personality, activity and exploratory behaviour, as well as colour-dependent novel object exploration in adult male mallard ducks (Anas platyrhynchos). We found that individuals that were immune-challenged during the middle (immediately following the completion of somatic growth) and late (during the acquisition of nuptial plumage) stages of development were more active in novel environments as adults relative to developmentally unchallenged birds or those challenged at an earlier developmental time point. Additionally, individuals challenged during the middle stage of development preferred orange and avoided red objects more than those that were not immune-challenged during development. Our results demonstrate that, in accordance with our predictions, early-life immune system perturbations alter the expression of personality traits later in life, emphasizing the role that developmental plasticity plays in shaping adult personality, and lending support to recent theoretical models that suggest that parasite pressure may play an important role in animal personality development.  相似文献   
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The development of insulin resistance in the obese is associated with chronic, low‐grade inflammation. We aimed to identify novel links between obesity, insulin resistance and the inflammatory response by comparing C57BL/6 with type I interleukin‐1 receptor knockout (IL‐1RI?/?) mice, which are protected against diet‐induced insulin resistance. Mice were fed a high‐fat diet for 16 wk. Insulin sensitivity was measured and proteomic analysis was performed on adipose, hepatic and skeletal muscle tissues. Despite an equal weight gain, IL‐1RI?/? mice had lower plasma glucose, insulin and triacylglycerol concentrations, compared with controls, following dietary treatment. The higher insulin sensitivity in IL‐1RI?/? mice was associated with down‐regulation of antioxidant proteins and proteasomes in adipose tissue and hepatic soluble epoxide hydrolase, consistent with a compromised inflammatory response as well as increased glycolysis and decreased fatty acid β‐oxidation in their muscle. Their lower hepatic triacylglycerol concentrations may reflect decreased flux of free fatty acids to the liver, decreased hepatic fatty acid‐binding protein expression and decreased lipogenesis. Correlation analysis revealed down‐regulation of classical biomarkers of ER stress in their adipose tissue, suggesting that disruption of the IL‐1RI‐mediated inflammatory response may attenuate cellular stress, which was associated with significant protection from diet‐induced insulin resistance, independent of obesity.  相似文献   
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Most estrous cycles in cows consist of 2 or 3 waves of follicular activity. Waves of ovarian follicular development comprise the growth of dominant follicles some of which become ovulatory and the others are anovulatory. Ovarian follicular activity in cows during estrous cycle was studied with a special reference to follicular waves and the circulating concentrations of estradiol and progesterone. Transrectal ultrasound examination was carried out during 14 interovulatory intervals in 7 cows. Ovarian follicular activity was recorded together with assessment of serum estradiol and progesterone concentrations. Three-wave versus two-wave interovulatory intervals was observed in 71.4% of cows. The 3-wave interovulatory intervals differed from 2-wave intervals in: 1) earlier emergence of the dominant follicles, 2) longer in length, and 3) shorter interval from emergence to ovulation. There was a progressive increase in follicular size and estradiol production during growth phase of each wave. A drop in estradiol concentration was observed during the static phase of dominant anovulatory follicles. The size of the ovulatory follicle was always greater and produced higher estradiol compared with the anovulatory follicle. In conclusion, there was a predominance of 3-wave follicular activity that was associated with an increase in length of interovulatory intervals. A dominant anovulatory follicle during its static phase may initiate the emergence of a subsequent wave. Follicular size and estradiol concentration may have an important role in controlling follicular development and in determining whether an estrous cycle will have 2 or 3-waves.  相似文献   
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The O-antigen chain from the lipopolysaccharide of Helicobacter pylori strain UA861 was determined to be composed of an elongated type 2 N - acetyllactosamine backbone, -[-->3)-beta-D-Gal-(1-->4)-beta-D-GlcNAc-(1- ]n-->, with approximately half of the GlcNAc units carrying a terminal alpha-d-Glc residue at the O -6 position. The O-chain of H.pylori UA861 was terminated by a N -acetyllactosamine [beta-D-Gal-(1-->4)-beta-D- GlcNAc] (LacNAc) epitope and did not express terminal Lewis X or Lewis Y blood-group determinants as previously found in other H.pylori strains. The absence of terminal Lewis X and Lewis Y blood-group epitopes and the replacement of Fuc by Glc as a side chain in the O- chain of H.pylori UA861 represents yet another type of lipopolysaccharide structure from H.pylori species. These structural differences in H.pylori lipopolysaccharide molecules carry implications with regard to possible different pathogenic events between strains and respective hosts.   相似文献   
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The first Australian record of the lily thrips, Liothrips vaneeckei Priesner, is reported from a bulb farm in Warragul South, Victoria. It is an occasional pest of Lilium bulbs, both in the field and in storage, particularly in the USA and several European countries, and is also infrequently found in considerable numbers on the corms of orchids.  相似文献   
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