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11.
Five treatments (short‐neck clam Ruditapes philippinarum and four formulated diets with the green microalgae Dunaliella tertiolecta or the golden‐brown microalgae Isochrysis galbana in the ratio (dw/dw) of 5% or 10% to that of clam meat) were used to investigate the growth performance and haemolymph quality of juvenile Chinese horseshoe crabs Tachypleus tridentatus under laboratory culture. At the end of the 12‐week study, various growth and moulting indicators as well as haemolymph biochemical parameters did not show any significant differences among the treatments. Significantly higher percentages of haemolymph amoebocyte viability and granular‐spherical amoebocyte state were noted in both 5% and 10% I. galbana‐supplemented diets compared to that of clam meat. However, the percentages of these two haemolymph parameters in juveniles fed with D. tertiolecta decreased significantly at the end of the experiment. Such differences were attributed to the presence of polyunsaturated fatty acid (PUFA), notably eicosapentaenoic acid (EPA), in I. galbana that was absent in D. tertiolecta and clam meat. Like many marine invertebrates, juvenile horseshoe crabs do not naturally obtain sufficient PUFAs from their diets to meet developmental and physiological needs; hence, supplementing microalgae with high levels of EPA in a protein‐rich diet boosts immune competence and the health status of juvenile horseshoe crabs while under culture.  相似文献   
12.
Apoptosis in the testis is required to ensure an efficient spermatogenesis. However, sometimes, defective germ cells that are marked for elimination during this process escape elimination in the testes, giving rise to ejaculates with increased percentages of abnormal and apoptotic spermatozoa and a high percentage of apoptotic bodies. Apoptosis markers in the ejaculate have been associated with low fertility, either in animals or humans. Therefore, the goal of this study was to investigate whether fresh equine semen contains apoptotic bodies [initially named Merocyanine 540 (M540) bodies] and to study the relationship between the quantity of these bodies and cell concentration, the volume of ejaculate, viability and motility. Moreover, we also studied whether the presence apoptotic bodies in fresh semen was related to the resistance of the stallion spermatozoa to being incubated at 37°C or being frozen and thawed. Fresh equine semen was stained with fluorescent dyes such as M540 and Annexin‐V. Active Caspase 3 was studied in fresh semen through Western blotting and immunofluorescence with a specific antibody. Sperm kinematics was assessed in fresh, incubated and thawed samples using computer‐assisted semen analysis, and viability was evaluated with the LIVE/DEAD Sperm Viability Kit. Overall, our results demonstrate for the first time the presence of apoptotic bodies in equine semen. The quantity of apoptotic bodies was highly variable among stallions and was positively correlated with Caspase 3 activity in fresh samples and negatively correlated with the viability and motility of stallion spermatozoa after the cryopreservation process.  相似文献   
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The genus Arachis is divided into nine taxonomic sections. Section Arachis is composed of annual and perennial species, while section Heteranthae has only annual species. The objective of this study was to investigate the genetic relationships among 15 Brazilian annual accessions from Arachis and Heteranthae using RAPD markers. Twenty-seven primers were tested, of which nine produced unique fingerprintings for all the accessions studied. A total of 88 polymorphic fragments were scored and the number of fragments per primer varied from 6 to 17 with a mean of 9.8. Two specific markers were identified for species with 2n = 18 chromosomes. The phenogram derived from the RAPD data corroborated the morphological classification. The bootstrap analysis divided the genotypes into two significant clusters. The first cluster contained all the section Arachis species, and the accessions within it were grouped based upon the presence or absence of the ‘A’ pair and the number of chromosomes. The second cluster grouped all accessions belonging to section Heteranthae.  相似文献   
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SUMMARY: Linear regression analysis was used to describe the decline in numbers of Culicoides brevitarsis Kieffer into winter with monthly maximum, average and minimum temperatures at the southern limits to its distribution in New South Wales. From this, low temperature thresholds were derived when C brevitarsis would be absent from the field. The low minimum threshold ± 2 SE (95% Confidence Interval) of 8.1 ± 0.3°C was used with historical temperature data to estimate the last month that the species should occur (March to June) and the mean number of months (2 to 6.5) below the threshold at 17 selected sites. Probability for survival during winter at these sites was estimated from years when the number of consecutive months below the threshold was ≤ 2 months. This varied from zero to 51% depending on the location of the site. Last occurrence was 0.7 months later on average and absolute probabilities for survival ranged from zero to 100% when the temperatures were increased by an arbitrary 2°C.  相似文献   
16.
秦律的赀罚与二年律令的罚金虽然名称完全不同,但两者具有继承关系。秦律的赀二甲是对盗窃额未满110钱-22钱的处罚,赀一盾是对未满22钱-1钱的处罚。秦律的这些内容由二年律令继承。赀罚原来分为赀一盾、赀二盾、赀一甲、赀二甲等四个等级,后来赀二盾逐渐消失,形成赀一盾、赀一甲、赀二甲三个等级,这三个等级的比例为1:2:4,与二年律令的罚金一两、二两、四两的比例关系相一致。赀一盾的罚额为672钱,与罚金一两的价额625钱相差不大。赀一盾的价额672钱与秦律规定的日均劳动价额8钱有关,以一日劳役为八钱计算,672钱  相似文献   
17.
Improving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll‐like receptors (TLR) mediate innate immune mechanisms via the production of pro‐inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30–50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll‐like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN‐G), and interleukin (IL)‐12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL‐6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro‐inflammatory cytokine mRNA expression.  相似文献   
18.
A previously unknown solid phase of H2O has been identified by its peculiar growth patterns, distinct pressure-temperature melting relations, and vibrational Raman spectra. Morphologies of ice crystals and their pressure-temperature melting relations were directly observed in a hydrothermal diamond-anvil cell for H2O bulk densities between 1203 and 1257 kilograms per cubic meter at temperatures between -10 degrees and 50 degreesC. Under these conditions, four different ice forms were observed to melt: two stable phases, ice V and ice VI, and two metastable phases, ice IV and the new ice phase. The Raman spectra and crystal morphology are consistent with a disordered anisotropic structure with some similarities to ice VI.  相似文献   
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Perinatal mortality and stillbirths were investigated in an extensively managed herd of Friesian cows and heifers calving over a 2‐year period: 504 cows were calved and 215 heifers. Cows were bred to Friesian and Jersey bulls using natural service. The perinatal fetal mortality rate was 7.5% for cows and 30% for heifers. An experienced stockman managed these calvings and veterinary assistance was required only on nine occasions. All stillborn fetuses were examined post‐mortem by the Veterinary Laboratories Agency, Carmarthen and no infectious agent was identified on any occasion. Thyroid hyperplasia was found in two fetuses. In blood samples taken from 10 late pregnant heifers, mean glutathione peroxidase values were 7.9 ± 1.7 IU/ml Packed Cell Volume (PCV). Tissues from eight fetuses were submitted to the University of Liverpool for histopathological examination; all presented lesions consistent with myocardial degeneration and necrosis of the left ventricle. Following treatment of 205 late pregnant heifers with sodium selenite and vitamin E, the overall perinatal mortality rate in these cattle fell to below 11%.  相似文献   
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