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排序方式: 共有751条查询结果,搜索用时 125 毫秒
1.
Interactions between different media and follicle‐stimulating hormone supplementation on in vitro culture of preantral follicles enclosed in ovarian tissue derived from collared peccaries (Pecari tajacu Linneaus, 1758)
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GL Lima VB Luz LF Lima RMP Rocha SV Castro TS Castelo APR Rodrigues JR Figueiredo AR Silva 《Reproduction in domestic animals》2018,53(4):880-888
The aim was to verify the effect of follicle‐stimulating hormone (FSH) supplementation to α‐MEM+ or TCM199+ media on the in vitro development of ovarian preantral follicles (PFs) derived from collared peccaries. Ovaries (n = 5 pairs) were collected and divided into fragments destined to control group (non‐cultured) or treatments that were cultured for 7 days. The PFs morphology, growth and activation were evaluated by classical histology. The immunohistochemistry markers Ag‐NOR and PCNA were used for nuclear proliferation analysis, and the picrosirius red labelling was used for ovarian extracellular matrix (ECM) evaluation. After 7‐day culture, only the TCM199+ treatment maintained the proportion of intact PFs similar to day 1 (63.2%), but no differences were found among treatments (p > .05). In addition, a significant increase in the growing follicles proportion was verified for all the treatments, indicating follicular activation (p > .05). By the Ag‐NOR analysis, only the TCM199+/FSH maintained the nuclear proliferation similar to the first day (p > .05). The picrosirius red staining revealed that the ECM remained intact in all the treatments (p > .05). We suggest the use of TCM199+ medium supplemented of FSH for the in vitro development of peccaries PFs under 7‐day culturing conditions. 相似文献
2.
Ricardo B. Leite Ricardo Afonso M. Leonor Cancela 《Aquaculture (Amsterdam, Netherlands)》2004,240(1-4):39-53
This study characterises Perkinsus atlanticus disease prevalence and intensity within the economically important beds of the clam Ruditapes decussatus along the Iberian Atlantic coast. Samples were collected from five different sites along the Portuguese coast (Ria Formosa, Ria do Alvor, V.N. Milfontes, Aveiro, Lagoa de Obidos) and in Galicia (Ria de Arosa) between winter 2000/2001 and 2002/2003. The infection level was evaluated by the Ray Fluid Thioglycollate medium (RFTM) method using the body burden assay. In addition, the measure of the condition index (CI) (percentage between the edible part and the total weight of the clams) was conducted to investigate a possible correlation between this parameter and the intensity of the infection. However, no clear relationship between infection intensity and condition index (CI) could be determined although a significant decline in CI was found for heavily infected clams. Results of a 2-year survey demonstrate the presence of Perkinsus sp. in all sampling sites albeit with different intensities. Sites where human interference was minimal showed the lowest levels of infection. There were no significant differences in Perkinsus sp. infection intensity between samples collected in winter and summer, in contrast with several studies describing higher intensities at the end of the summer. Nevertheless, major differences were observed from year to year and site to site, indicating that factors other than those responsible for seasonal climatic variations might affect the prevalence and the intensity of Perkinsus sp. infection. 相似文献
3.
Elayna Cristina da Silva Maciel Edivaldo Sampaio de Almeida Filho William Bertoloni Janessa Sampaio de Abreu 《Journal of the World Aquaculture Society》2014,45(1):35-44
Different stunning methods (carbon dioxide [CO2] and hypothermia) used in industrial fish processing were compared with asphyxia in air, which is used in traditional fishing, to evaluate the effects of these methods on the stress responses and the meat quality of the Amazon hybrid surubim, Pseudoplatystoma fasciatum female × Leiarius marmoratus male. After the application, blood and behavioral indicators were evaluated. Following death by gill cutting, the fish were gutted, and analyses of muscle pH, rigor mortis, the exudation of the meat, and coloration were performed. Significantly higher levels of cortisol and glucose were exhibited by the fish subjected to asphyxia than by the fish stunned by either CO2 or hypothermia. The fish subjected to asphyxia displayed decreasing muscle pH during the first 2 h after death and showed higher rates of rigor mortis after 3 h than the fish that were stunned by the other two methods. The asphyxia is a practice that exposes fish to suffering by causing an increase in stress responses, which affects meat quality. The immersion of fish in water and ice (hypothermia) for 5 min was more effective stunning method than the use of CO2, resulting in higher loss of sensibility and greater welfare. 相似文献
4.
Isabel Oliveira Cosentino Mario Felipe Alvarez Balaro Felipe Seabra Cardoso Leal Lucas de Figueiredo Cardoso Barbosa Fernanda Martins Gonçalves Gabriel Feliciano Felizardo Marina Monteiro Netto Felipe Zandonadi Brandão 《Reproduction in domestic animals》2020,55(11):1655-1659
This study aimed to evaluate the exogenous progesterone (P4) effect on the luteal function from Day 16 to Day 21 of the oestrous cycle in inseminated goats with unknown pregnancy status. A total of 54 does passed through a short progestin-based synchronization protocol and, on Day 16 of the following oestrous cycle, 27 does received a new P4 device which was retained until Day 21. Blood samples were collected daily from all does during this period, as well as on Day 24. Pregnancy diagnoses were performed on Day 30. Serum P4 values from 26 animals (GNPSP: Group of non-pregnant does with second sponge: n = 8; GNPNSP: Group of non-pregnant does without second sponge: n = 6; GPSP: Group of pregnant does with second sponge: n = 5; GPNSP: Group of pregnant does without second sponge: n = 7) were determined by radioimmunoassay commercial kits. No P4 differences were found between groups (GNPSP: 3.1 ± 2.8; 1.7 ± 1.8; 0.4 ± 1.0; and 0.0 ± 0.0 vs. GNPNSP: 4.4 ± 1.8; 3.0 ± 2.2; 0.8 ± 0.8; and 0.0 ± 0.0 or GPSP: 4.2 ± 1.0; 3.4 ± 0.6; 3.3 ± 1.6; 3.2 ± 0.9; 3.6 ± 1.2; 3.5 ± 1.3; 2.7 ± 1.3 vs. GPNSP: 4.4 ± 1.6; 3.6 ± 1.5; 3.7 ± 1.5; 3.8 ± 1.4; 3.2 ± 1.2; 3.1 ± 1.2; 3.6 ± 1.1; D16, D17, D18, D19, D20, D21, D24, respectively) or for the interaction of group and time. In conclusion, a second progestogen device had no effect on luteolysis or early pregnancy in the following oestrous cycle. 相似文献
5.
Plasma biomarkers profile of female dogs with mammary carcinoma and its association with clinical and pathological features
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R. P. Soares L. G. R. Ribeiro K. A. Damasceno A. T. Costa A. Teixeira‐Carvalho O. A. Martins‐Filho G. D. Cassali 《Veterinary and comparative oncology》2016,14(1):88-100
The immunological biomarkers profiles were evaluated using Luminex as putative measures to monitor canine mammary carcinomas (MCs). Forty female dogs were categorized into benign mixed tumour (MC‐BMT = 28) and mammary carcinoma (MC=12). The ascendant biomarker signatures were used to compare the groups. For example, a higher frequency of MC‐BMT animals producing IL‐6, CXCL‐8 and CXCL‐10 was observed, whereas for the MC group IL‐2 and CXCL‐8 were detected. MC‐BMT animals without metastasis had an increase in the levels of IL‐2, CXCL‐8, CXCL‐10, IL‐6, TNF‐α, IL‐15 and a decrease in IL‐10 and CXCL‐8. MC‐BMT animals with metastasis showed only an increase in CXCL‐10 and a decrease in IL‐18. After comparing the ascendant signatures following the presence of metastasis in both groups, a higher frequency of dogs exhibiting IL‐10 production was observed. Pearson correlation (P = 0.0273) and receiver operating characteristic (ROC) curve analysis revealed that this pattern was associated with worse outcome and lower survival rates in MC animals. 相似文献
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8.
de Ramos Eduarda Kalena Kirsch Pazdiora Paulo Cesar Dallagnol Leandro José de Souza Mayara Rodrigues de Araujo Filho Jeronimo Vieira 《植物病害和植物保护杂志》2023,130(1):211-214
Journal of Plant Diseases and Protection - Tobacco (Nicotiana tabacum L.) is one of the major nonfood crops in the Southern of Brazil. During 2019/2020 and 2020/2021 crop seasons, Root Knot... 相似文献
9.
B. Itier D. Flura K. Belabbes P. Kosuth G. Rana L. Figueiredo 《Irrigation Science》1992,13(3):109-114
Summary The measurement of water consumption in the field is normally restricted to research purposes, although the development of practical field criteria for timing water application is required to improve crop productivity. To develop such criteria irrigation experiments on Soybean were conducted from flowering to grain filling at four locations which differed in their soil properties and the convective contribution of their climates to potential evapotranspiration. The energy balance, predawn leaf water potential (PLWP), soil moisture depletion, and a crop water stress index (CWSI) based on foliage temperature were measured. The range of soil, atmospheric, phenological and irrigation conditions, produced a common, linear relation between relative evapotranspiration (rET) and the logarithm of -PLWP. Correlation with the temperature based CWSI was weak. A similar relation with PLWP for other C3 plants was also derived from data in the literature. This relation could be helpful for irrigation scheduling once the critical values of rET for crop productivity are known. 相似文献
10.
Plant breeders have been trying to predict the performance of hybrids based on their parental performance. One application of molecular markers is its use in selection. The objectives were to map quantitative trait loci (QTL) and verify its congruence in maize lines and in their testcrosses and verify the possibility to select testcrosses from the predicted means of the lines by using information from markers. Two-hundred and fifty six lines and the testcrosses of these lines with two testers were evaluated in six environments, considering grain yield, plant lodging, days to anthesis and silking, anthesis-silking interval, plant and ear height and ear placement. QTL were mapped in the lines and in testcrosses and the predicted means of the lines were computed based on QTL effects and in all markers of the genome. The congruence of QTL detected in the lines and testcrosses were small for all traits. The correlations between the predicted means of the lines and the phenotypic means of the testcrosses ranged from low for grain yield to moderate for cycle and stature traits. The highest coincidences of the lines and selected testcrosses were observed for cycle and stature traits and the lowest for grain yield. Even by using molecular markers information, it is only possible to predict the testcrosses performance from the lines information to less complex traits and with reduced dominance effect. For complex traits and with pronounced dominance effect, information of markers must be obtained directly in the testcrosses, so they can be used for selection. 相似文献