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1.
《Animal : an international journal of animal bioscience》2018,12(10):2138-2146
Numerous studies have shown that providing straw to pigs can reduce undesirable behaviours such as aggression, tail biting and stereotypy. The measurement of various neuromodulators can be helpful in assessing the development of positive behaviours and overall animal welfare. The oxytocin release is frequently linked to positive emotions and positive welfare. It has been suggested that oxytocin modulates the serotoninergic system. This study aims to investigate the potential effect of straw provision in pigs on peripheral levels of oxytocin and serotonin. In total, 18 mini-pigs were involved in an exploratory study conducted in two parallel groups, Enriched (n=10) and Control (n=8) groups. Pigs were divided by group and housed in pens of two individuals. Straw was provided continuously only in Enriched group and renewed each day for 2 weeks. Two blood samples were drawn from each animal 5 to 10 min before providing the straw, and 15 min after providing straw, during the 1st week, to analyse peripheral changes in oxytocin and serotonin before and after straw provision, and determine the existence of a putative short-term effect. The same procedure was carried out for Control group, without straw provision. Long-term effects of straw provision were also examined using blood samples drawn at the same hour from each animal in the 2nd and 3rd weeks. During this time, animals had the permanent possibility to explore the straw in Enriched group but not in Control group. At the end of each week, one animal-keeper completed two visual analogue scales for each mini-pig regarding the difficulty/ease to work with and handle it and its trust in humans. Results showed peripheral oxytocin increases in both groups after 2 weeks (P=0.02). Results did not demonstrate any effect of providing straw to allow exploratory behaviour on peripheral serotonin. Other results were not significant. This preliminary study explored the relationship between peripheral oxytocin and serotonin and the presence of straw that allow pigs to perform exploratory behaviour, suggesting that there was no relationship between them. Some future studies may include crossing oxytocin and serotonin with other parameters, such as behavioural measures, to obtain more information about the true state of the animal and any possible relationship with pig welfare. 相似文献
2.
《Biomarkers》2013,18(2):186-191
Context: Usefulness of circulating Chromogranin A (CgA) for the diagnosis of neuroendocrine tumors (NEN) is controversial. The aim of the present study was to assess the actual role of this marker as diagnostic tool. Methods: Serum blood samples were obtained from 42 subjects affected with NEN, 120 subjects affected with non-endocrine neoplasias (non-NEN) and 100 non-neoplastic subjects affected with benign nodular goitre (NNG). Determination of CgA was performed by means of immunoradiometric assay. Results: The CgA levels among NEN-patients were not significantly different from NNG and non-NEN subjects. The Receiver operating characteristic (ROC) curves analysis failed to identify a feasible cut-off value for the differential diagnosis between NEN and the other conditions. Conclusion: Serum CgA is not helpful for the first-line diagnosis of NEN. 相似文献
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Mortality of the collembole species Orchesella cincta (L.), due to predation by the carabid Notiophilus biguttatus F., has been measured in the laboratory at three levels of prey density. Prey densities were chosen such that the predator's consumption at the lowest prey density was a little above the maintenance ration. Between the two lowest prey densities, mortality increased significantly with prey density. We presume that density-dependent search activity by the predator is responsible for the positive density-dependent mortality. A method is proposed to solve the problem of decreasing prey density during the observations.
Relation positive entre la densité de Orchesella cincta et la mortalité due à la prédation part Nothiophilus biguttarus
Résumé Cet article décrit l'importance de la prédation par le carabe N. biguttatus en fonction de la densité de la proie, O. cincta. Les résultats montrent que, sous l'effet de la prédation, la mortalité de la proie augmente avec sa densité. La quantité minimale de proies qui doit être consommée pour permettre la reproduction du carabe, a été déterminée. La relation entre la fécondité du carabe et l'effectif consommé, montre l'effet stabilisant de la prédation sur les populations de proies.La relation de dépendance de la densité observée avec la mortalité est due à une modification du comportement du carabe en fonction de la densité de sa proie. Nous proposons un modèle permettant de prévoir la régression de la population de proies sous les effets de la prédation.相似文献
5.
Consumption of larvae and females ofAphis craccivora Koch by 1st and 4th larvae and adults ofCheilomenes vicina (Muls.) was studied under fluctuating temperature (24–30°C). The early aphid instars were consumed in significantly greater
numbers than later instars and females.
The feeding rates ofC. vicina were significantly positively correlated with the population density of prey. The number of prey consumed daily by each predator
stage tested, increased more steeply at lower than at higher prey densities, exhibiting thus the type 2 functional response
Résumé Consommation des larves et des ♀ d'Aphis craccivora par les11e stades, les 4e stades et les adultes deCheilomenes vicina a été étudiée à une température variant de 24 à 30°C. Les jeunes stades du puceron sont consommés en nombre plus grand significativement que les derniers stades et les ♂. Les taux d'alimentation deC. vicina manifestent une corrélation hautement significative avec la densité de population de la proie. Le nombre de proies consommées quotidiennement par chaque stade considéré du prédateur augmentait plus brusquement aux faibles qu'aux fortes densités de proies, manifestant ainsi chez le prédateur le type 2 de réponse fonctionnelle.相似文献
6.
Anaerobic, Gram-positive cocci were obtained from chicken feces by direct isolation, which grew on the purines uric acid, xanthine, 6,8-dihydroxypurine, guanine, and hypoxanthine. Adenine and glycine were fermented, but not as readily. Acetate, formate, ammonia, and CO2 were products. The isolated strains were nutritionally non-fastidious, however, they required selenite, molybdate, and tungstate as micronutrients. The cells were spherical and 0.5–0.9 m in diameter. The addition of bile salts enhanced the growth rate in most cases. The organisms proved to be quite resistant to lysis. The guanosine-plus-cytosine (G+C) content of their deoxyribonucleic acid was 33.6 to 34.8 mol%. The peptidoglycan was of the same structure (Gly-Lys-d-Asp) as reported for the anaerobic cocci of Hare group IX. However, the latter strains could only utilize glycine, not purines. Therefore, it is proposed to form a new species, Peptostreptococcus barnesae sp. nov.This paper is dedicated to Prof. Dr. Norbert Pfennig on the occasion of his 60th birthday 相似文献
7.
The Sec1 Family: A Novel Family of Proteins Involved in Synaptic Transmission and General Secretion 总被引:10,自引:1,他引:9
Abstract: The Sec1 family, a novel family of proteins involved in synaptic transmission and general secretion, is described. To date, 14 members of this family have been identified: four yeast proteins, Sec1, Sly1, Slp1/Vps33, and Vps45/Stt10; three nematode proteins, Unc-18 and the homologues of Sly1 and Slp1; the Drosophila Rop; and six mammalian proteins, the rat Munc-18/n-Sec1/rbSec1A and rbSec1B, the mouse Munc-18b/muSec1 and Munc-18c, and the bovine Munc-18 and mSec1. The mammalian proteins share 44–63% sequence identity with the nematode Unc-18 and Drosophila Rop proteins and 20–29% with the yeast proteins and their nematode homologues. The Sec1 proteins are mostly hydrophilic and lack a transmembrane domain. Nevertheless, Sec1 proteins are found as membrane-bound proteins. Some of them are also found as soluble, cytoplasmic proteins. Binding of the rat brain Sec1 to the presynaptic membrane may be due to strong interaction with syntaxin, an integral component of this membrane. The rat brain Sec1 is also bound to Cdk5, a neural cyclin-dependent kinase. The Sec1 proteins play a positive role in exocytosis. Loss of function mutations in SEC1 , SLY1 , or SLP1 result in blocking of protein transport between distinct yeast subcellular compartments. Inactivation of unc-18 and rop results in inhibition of neurotransmitter release and, in the case of rop , inhibition of general secretion as well. In addition, studies of Rop and n-Sec1 indicate that they also play a negative role in synaptic transmission, mediated by their interaction with syntaxin. A working model addressing the dual regulative role of the Sec1 proteins in secretion is presented. 相似文献
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大鼠食管胸段和腹段壁内乙酰胆碱酯酶(AChE)阳性神经存在于神经束和分支的粗细神经纤维内,也见于外膜丛,肌间丛,粘膜下丛和粘膜肌内。食管肌层内AChE阳性神经纤维多而密集,而食管腹段肌内尤为丰富,肌间神经纤维末梢分布于肌束表面,可能与控制肌纤维活动有关;分布于肌内,粘膜下层和上皮基部的AChE阳性神经中,尚含有内脏感觉神经纤维。食管壁的肌间丛和粘膜下丛内散在有多极形和卵园形的AChE阳性神经元,在食管腹段内数多,而以中小型神经元为主。 相似文献
10.
本文是从棉籽饼粕中,应用732阳离子树脂柱提取碱性氨基酸。研究结果表明,碱性氨基酸与中性氨基酸之间交叉部分较小。因此,本法即简化了提取工序,又缩短了操作时间,大大提高了氨基酸的分离效果。 相似文献