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151.
J Mona e Pinto V Pavanelo Jr L Alves de Fátima LM Medeiros de Carvalho Sousa G Pacheco Mendes R Machado Ferreira H Ayres P Sampaio Baruselli F Palma Rennó P de Carvallo Papa 《Reproduction in domestic animals》2014,49(3):453-462
The uterus plays an essential role in mammalian reproduction and is a target of several hormonal protocols used to improve fertility in cattle. Many studies highlighted the importance of eCG treatment following fixed‐time artificial insemination in improving follicular growth, ovulation and pregnancy rates in cattle. Moreover, eCG has been implicated in angiogenesis, leading to important changes in uterine blood flow and vascularisation. However, there is still a lack of information regarding the specific alterations induced by eCG upon glandular and vascular characteristics of bovine uterus. To investigate the influence of eCG on: uterine thickness and area; uterine artery diameter and area; uterine vascular and gland density; and the expression of the VEGFA‐system, the uteri of crossbred beef cows were collected. All cows were submitted to follicular wave emergence synchronization. On day four of protocol, cows submitted to superovulation (n = 6) received 2000 IU eCG, on day eight, after expected follicular deviation, cows submitted to stimulatory treatment (n = 5) received 400 IU eCG. Control cows (n = 5) did not receive eCG. On day five po cows were subjected to ultrassonographic evaluation and slaughtered for uterine tissue sampling on day six po. Uterine vessels and glands were quantified by the counting point stereological method. The VEGFA‐system was localized in different cellular types, showing no qualitative or quantitative differences in the site of expression or the intensity of the positive signal among the groups. Vascular density was decreased in the endometrium of stimulated and myometrium of superovulated cows compared with the control ones, which showed higher vascular density in the myometrium and endometrium of the ipsilateral uterine horn. The uterine gland density was higher in superovulated compared with stimulated and control cows. Thus, we can infer that stimulatory or superovulatory treatments with eCG influence the vascular density in the endometrium and myometrium in cattle. 相似文献
152.
Henderson Ayres Roberta Machado Ferreira Jos Ribamar de Souza Torres-Júnior Clarice Garcia Borges Demtrio Csar Gonalves de Lima Pietro Sampaio Baruselli 《Livestock Science》2009,123(2-3):175-179
The aim of the present study was to determine the relationship among body weight (BW), body condition score (BCS) and rump fat thickness (RFAT) measured by ultrasonography, and validate the relationship between BCS and RFAT over the time. Two hundred sixty and six Nelore cows had their BW, BCS and RFAT evaluated at five different moments during the production cycle: M1) weaning; M2) parturition, M3) 42 days post-partum; M4) 82 days post-partum and M5) 112 days post-partum. A BCS value was attributed for each cow following a 1 to 5 points scale. Ultrasonographic images for RFAT measurement were obtained using a 3.5 MHz linear transducer. Images were immediately analyzed as soon as they were formed and frozen. Body condition scores and ultrasound measurements were collected on the same day by a single trained technician. The relationship between BCS and RFAT values was investigated by regression models. The analysis of similarity among the five obtained models was performed using the proc MIXED from SAS and the correlations among variables were analyzed with proc CORR from SAS. The BCS was able to predict RFAT in Nelore cows in all different moments evaluated. Also, it was shown that BCS presented high correlation (r = 0.82 to 0.93) and relationship (R2 = 0.73 to 0.92) with RFAT. However, both BCS and RFAT showed low correlation (r = 0.37 to 0.50) and relationship (R2 = 0.13 to 0.25) with BW. The BCS classification by visual method using a 1 to 5 point scale, was able to predict the RFAT in Nelore cows over the time. 相似文献
153.
Veterinary Research Communications - 相似文献
154.
Christoph F.J. Meyer Ludmilla M.S. Aguiar Julio Baumgarten Jean-François Cosson Jakob Fahr Neil Furey Robert Hodgkison Kirsten G. Jung Thomas H. Kunz Isabel Moya Paul A. Racey Erica M. Sampaio Christian C. Voigt Christa D. Weise 《Biological conservation》2010,143(11):2797-2807
Bats are ecologically important mammals in tropical ecosystems; however, their populations face numerous environmental threats related to climate change, habitat loss, fragmentation, hunting, and emerging diseases. Thus, there is a pressing need to develop and implement large-scale networks to monitor trends in bat populations over extended time periods. Using data from a range of Neotropical and Paleotropical bat assemblages, we assessed the ability for long-term monitoring programs to reliably detect temporal trends in species abundance. We explored the magnitude of within-site temporal variation in abundance and evaluated the statistical power of a suite of different sampling designs for several different bat species and ensembles. Despite pronounced temporal variation in abundance of most tropical bat species, power simulations suggest that long-term monitoring programs (?20 years) can detect population trends of 5% per year or more with adequate statistical power (?0.9). However, shorter monitoring programs (?10 years) have insufficient power for trend detection. Overall, our analyses demonstrate that a monitoring program extending over 20 years with four surveys conducted biennially on five plots per monitoring site would have the potential for detecting a 5% annual change in abundance for a suite of bat species from different ensembles. The likelihood of reaching adequate statistical power was sensitive to initial species abundance and the magnitude of count variation, stressing that only the most abundant species in an assemblage and those with generally low variation in abundance should be considered for detailed population monitoring. 相似文献
155.
156.
Angela Rosa Piergiovanni Incoronata Galasso Pietro Perrino Domenico Pignone 《Genetic Resources and Crop Evolution》1995,42(4):347-352
Summary 27 accessions ofVicia benghalensis from different geographical origins constitute the pool on which the present study was performed. Genetic variation among
the samples was biochemically and cytologically evaluated: seed storage protein profiles and C-banded karyotypes were analysed
from single individuals of each accession.
SDS-PAGE has shown the possibility to divide the samples into two groups, each characterized by specific protein profiles.
The two patterns were indicated as A and B. From individual seed electrophoresis it was ascertained that samples possessing
the pattern A showed a low level of individual variation, while those possessing the pattern B were highly polymorphic, thus
suggesting differences in the allogamic rate.
The cytological analysis demonstrated the presence of two groups of accessions, one being much richer in heterochromatin as
evidenced by C-banding (H+) than the other (H-). The analysis of biochemical and karyological data showed a constant association between pattern A and karyotype H− and between pattern B and karyotype H+.
On the basis of these results it is proposed to considerV. benghalensis as a highly heteromorphic species, in which two groups may be identified. 相似文献
157.
Cefarelli G D'Abrosca B Fiorentino A Izzo A Monaco P 《Journal of agricultural and food chemistry》2005,53(9):3525-3529
A total of 12 fatty acid esters of Z- and E-p-coumaryl alcohol were isolated from cv. Annurca apple fruit and characterized. This apple variety is widely cultivated in the south of Italy, and the fruits typically undergoe a reddening treatment after harvest. Structures of the p-coumaryl esters were elucidated by GC-MS and (1)H and (13)C NMR after purification of individual compounds by HPLC. It was found that the esters are localized in the fruit peel. During reddening of the fruit, there was a substantial increase in the amount of esters and particularly in molecular species with unsaturated fatty acids. The individual compounds were tested for antioxidant activity, and over half were shown to be at least as effective as alpha-tocopherol. 相似文献
158.
Romano Dallai Pietro P. Fanciulli Francesco Frati Eugenio Paccagnini Pietro Lupetti 《Pedobiologia》2004,48(5-6):493-501
The winding process leading to the formation of rolled-up spermatozoa in Collembola is described. It is a phenomenon common to all collembolan species examined so far and it starts with the organization of a cytoplasmic flattened evagination beneath the head of the elongated spermatid, which gives rise to an extracellular cavity. Within this cavity secretory material produced by the epithelial cells of testes is progressively stored. The spermatozoon, whose cytoplasm is reduced to a thin layer, enrolls around this material. The final appearance is that of a spheroidal or lenticular structure containing dense material in the central extracellular cavity; this cavity is surrounded by the flattened sperm in whose cytoplasm the sperm components forms several spires. The material into the extracellular cavity becomes progressively denser and has a different appearance in the species examined. 相似文献
159.
Karl Hammer Pietro Perrino Domenico Pignone 《Genetic Resources and Crop Evolution》1987,35(2):389-399
Summary In continuation of collecting activities in the last six years a further mission has been carried out in South Italy jointly by staff members of the Istituto del Germoplasma, Bari, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben, in September 1986 for exploring and collecting plant genetic resources. In this year South-eastern parts of Calabria and the Ìsole Ègadi have been covered. 90 samples, mainly of vegetables, grain legumes and some cereals, could be collected. The material represents variable land-races and wild relatives of crop plants. From the last groupBrassica, Beta and some wild cereals, asSecale, Aegilops andDasypyrum, should be mentioned. With this mission the exploration of South Italy is nearly completed. Further activities will concentrate to some selected regions.
Sammlung pflanzlicher und genetischer Ressourcen in Süditalien 1986
Zusammenfassung In Fortführung von Sammlungsaktivitäten der letzten sechs Jahre, wurde im September 1986 eine weitere Sammelreise, gemeinsam von Mitarbeitern des Istituto del Germoplasma, Bari, und des Zentralinstituts für Genetik und Kulturpflanzenforschung, Gatersleben, unternommen, die dem Studium und der Sammlung pflanzlicher genetischer Ressourcen diente. In diesem Jahr wurden südöstliche Teile Kalabriens und die Ìsole Ègadi erfaßt. 90 Proben, besonders von Gemüsen, Körnerleguminosen und einigen Getreiden, konnten gesammelt werden. Das Material besteht aus variablen Landsorten und wildwachsenden Verwandten der Kulturpflanzen. Aus der letztgenannten Gruppe sindBrassica, Beta und einige Wildgetreide, wieSecale, Aegilops undDasypyrum, zu nennen. Mit dieser Sammelreise ist die Exploration Süditaliens im wesentlichen abgeschlossen. Weitere Aktivitäten werden sich auf einige ausgewählte Gebiete beschränken.
1986
, () (), 1986 , . - . 90 , , , . . Brassica, Beta , Secale, Aegilops Dasypyrum. . .相似文献
160.
Fiorentino A Gentili A Isidori M Monaco P Nardelli A Parrella A Temussi F 《Journal of agricultural and food chemistry》2003,51(4):1005-1009
Olive oil mill wastewaters (OMWs) show significant polluting properties due to their content of organic substances, and because of their high toxicity toward several biological systems. Wastewaters' toxicity has been attributed to their phenolic constituents. A chemical study of wastewaters from a Ligurian oil mill characterized phenolic products such as 1,2-dihydroxybenzene (catechol), derivatives of benzoic acid, phenylacetic acid, phenylethanol, and cinnamic acid. The OMWs were fractioned by ultrafiltration and reverse osmosis techniques and tested for toxicity on aquatic organisms from different trophic levels: the alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum); the rotifer Brachionus calyciflorus; and two crustaceans, the cladoceran Daphnia magna and the anostracan Thamnocephalus platyurus. The fraction most toxic to the test organisms was that from reverse osmosis containing compounds of low molecular weight (<350 Da), and this was especially due to the presence of catechol and hydroxytyrosol, the most abundant components of the fraction. 相似文献