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排序方式: 共有409条查询结果,搜索用时 218 毫秒
111.
Francesca Mercati Paula Domingo Rolando Pasquariello Cecilia Dall'Aglio Alessandro Di Michele Katia Forti Paolo Cocci Cristiano Boiti Lidia Gil Massimo Zerani Margherita Maranesi 《Reproduction in domestic animals》2020,55(1):29-37
Freeze-drying (FD) has been exhaustively tried in several mammalian species as an alternative technique to sperm cryopreservation, but few studies have been done in rabbits (Oryctolagus cuniculus). The main objective of this study was to compare the protective effect of various antioxidants added to EDTA medium on structural and functional components of FD rabbit spermatozoa and on their status of global DNA methylation. FD media used were composed of basic FD medium (10 mM Tris-HCl buffer and 50 mM NaCl) supplemented with either 50 mM EDTA alone (EDTA) or added with 105 µM of rosmarinic acid (RA, EDTA-RA) or 10 µM of melatonin (MLT, EDTA-MLT). The effect of each medium on the preservation of FD spermatozoon structure was evaluated with light and scanning electron microscopy (SEM). Global DNA methylation was quantified in all FD sperm samples as well as in fresh spermatozoa. Morphologically, fracture points were evidenced in the neck, mid and principal piece of the spermatozoon tail. No differences in spermatozoon fracture points were evidenced among FD treatments: intact spermatozoa were the largest (p < .01) category, whereas the most frequent (p < .01) injury was the neck fracture, resulting in tailless heads. At SEM, the head of spermatozoa showed a well-conserved shape and intact membrane in all treatments. DNA methylation status was the same in all FD treatments. In conclusion, supplementation of EDTA, EDTA-RA and EDTA-MLT during FD preserved rabbit sperm morphological integrity and methylation status as well. Therefore, the difficulty of getting viable offspring using FD semen is likely unrelated to the impact of the lyophilization process on DNA methylation and morphology of lyophilized spermatozoa. 相似文献
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113.
José A Bechara Juan Pablo Roux Federico J Ruiz Díaz Carolina I Flores Quintana & Cecilia A Longoni de Meabe 《Aquaculture Research》2005,36(6):546-553
The effect of supplemental feeds with different levels of crude protein on pond water quality and food utilization efficiency by pacú (Piaractus mesopotamicus) was evaluated in a semi‐intensive culture system. Fish were stocked at a density of one individual per m2, raised for 299 days, and fed isocaloric diets containing soybean meal, blood and bone meal, and yellow maize. Dietary treatments consisted of diets containing 25%, 35%, and 45% crude protein. Ponds receiving the two highest protein levels showed significantly higher values of alkalinity, conductivity and nitrites. High dietary protein diets resulted in no significant improvements in final weight (336.4±77.2, 308.2±92.6 and 368.4±82.2 g, mean±standard deviation, for 25%, 35% and 45% protein levels respectively). Moreover, fish carcass composition was not significantly different among treatments. Instead, significant augmentations in feed conversion ratio (1.36, 1.54 and 1.73 respectively) and reductions in protein retention (35.7%, 33.5% and 29.0% respectively) occurred as protein levels increased. Results indicate that at the lowest protein level, pacú growth rates and carcass composition were similar to the other experimental treatments, with a significant improvement in pond water quality and feed utilization efficiency. 相似文献
114.
A feeding experiment was conducted to examine the potential of a commercial steam-processed-feather meal (SPFM) and feathers enzymatically hydrolysed for 60 or 120 min (EHF60 and EHF120) as substitutes for fishmeal (FM) in diets for white shrimp juveniles. Enzymatically hydrolised feathers or SPFM were blended through an extruder with soyabean meal (SBM) in a 1:1 ratio (EHF-SBM, SPFM-SBM). Isoproteic and isolipidic diets were formulated to contain 9% EHF60-SBM, 9% EHF120-SBM and 18% EHF60-SBM. These diets were compared with a diet containing 13.7% SPFM-SBM and a control diet designed to contain 18.4% FM and no feather. Quadruplicate groups of 15 shrimp (0.33 g initial-body weight) were fed twice a day on each diet for 4 weeks. The weight gain of shrimp fed on the three EHF-SBM diets did not differ from that of shrimp fed on the FM-control diet; however, shrimp fed on the SPFM-SBM diet gained less weight. The EHF60 and EHF120 coextruded with SBM in a 2:1 ratio were evaluated in a commercial rearing pond. Both ingredients included at 20% in the test diets were compared with a control diet containing 17.8% FM. Triplicate groups of juvenile shrimp (3.4 g initial-mean weight), randomly allocated in 1 m3 plastic cages, were fed with the test diets during 30 days. Growth (weight gain, specific-growth rate (SGR)) and nutritional value of the diets, food conversion ratio (FCR), protein-efficiency ratio (PER), digestibility were similar. In summary, these results indicate that white shrimp can be fed with a practical diet containing 20% EHF-SBM (2:1) without impairing growth or food conversion. The use of 20% EHF-SBM (2:1) allowed the fish-meal portion to be reduced by nearly by 55%. 相似文献
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116.
Matito C Agell N Sanchez-Tena S Torres JL Cascante M 《Journal of agricultural and food chemistry》2011,59(9):4489-4495
UV radiation leads to the generation of reactive oxygen species (ROS). These molecules exert a variety of harmful effects by altering key cellular functions and may result in cell death. Several studies have demonstrated that human skin can be protected against UV radiation by using plant-derived antioxidants. Here we evaluated the in vitro capacity of several antioxidant polyphenolic fractions from grape, which differ in their degree of polymerization and percentage of galloylation, to protect HaCaT human keratinocytes against UV-induced oxidative damage. These fractions inhibited both basal and UVB- or UVA-induced intracellular ROS generation in this cell line. Consequently, the same fractions inhibited p38 and JNK1/2 activation induced by UVB or UVA radiation. The highest protective effect was for fractions rich in procyanidin oligomers and gallate esters. These encouraging in vitro results support further research and should be taken into consideration into the clinical pharmacology of plant-derived polyphenolic extracts as novel agents for skin photoprotection. 相似文献
117.
Georgiou AS Gil MA Almiñana C Cuello C Vazquez JM Roca J Martinez EA Fazeli A 《Reproduction in domestic animals》2011,46(6):1017-1021
Complement component 3 (C3) has well-established roles within immune system, but its roles outside of immune system are less characterized. The extensive presence of C3 throughout the female reproductive tract, and its temporal, and gamete-specific regulation of expression suggest a potential role for C3 in reproduction. In the present investigation, the effects of C3, C3b and iC3b on porcine oocyte maturation, fertilization and embryonic development were examined. We identified the ability of iC3b to positively influence oocyte maturation. No effects on fertilization efficiency, penetration rates, polyspermy and blastocyst formation were observed. However, C3, C3b and iC3b presence in embryo culture medium resulted in fewer total cells in test blastocysts compared to control blastocysts. The results of this study indicate a potential function for iC3b in oocyte maturation. Furthermore, it was demonstrated that the presence of either C3, C3b or iC3b has a negative influence on early embryonic development in the porcine species. 相似文献
118.
119.
Romain Pariaut DVM Carley Saelinger VMD Patricia Queiroz-Williams DVM MS Keith N. Strickland DVM H. Cecilia Marshall DVM 《Journal of Veterinary Cardiology》2011,13(3):203-210
This report describes the use of an implantable cardioverter-defibrillator (ICD) in a young German shepherd dog afflicted with inherited ventricular arrhythmias. Proper generator and lead placement was necessary for successful termination of ventricular fibrillation during device testing at the time of implantation. The risks of inappropriate therapy triggered by sinus tachycardia and oversensing of the T wave were controlled by extensive programming of the device. Following spontaneous resolution of the arrhythmia and due to the development of sepsis associated with the device, the ICD was successfully removed. 相似文献
120.
Teixeira M Gil F Vazquez JM Cardoso L Arencibia A Ramirez-Zarzosa G Agut A 《Veterinary journal (London, England : 1997)》2007,174(1):133-138
The purpose of this study was to provide an atlas of the normal anatomy of the canine abdomen using helical computed tomographic (CT) images of the abdomen in four mature cross-breed dogs. The dogs were supported in sternal recumbency under general anaesthesia and scans were performed with 5 mm collimation and a pitch of 1. All sections were imaged with soft-tissue window settings and the cranial abdomen was also imaged with mediastinum-vascular window settings. CT scans were performed immediately after iodinated contrast medium was injected into the cephalic vein at 2 mL/kg. Iodinated contrast medium (10 mL/kg) was administered orally 2 h before the scan with a further 3 mL/kg administered immediately prior to scanning. A cross-sectional anatomy atlas was used to identify the structures of the abdominal cavity. Clinically relevant anatomical structures were identified and labelled in the CT images. 相似文献