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21.
Mehdi Azari Mojtaba Kafi Bita Ebrahimi Roya Fatehi Mahboobeh Jamalzadeh 《Veterinary research communications》2017,41(1):49-56
Objective
To examine the maturational competence, embryo development and expression of genes involved in oocyte maturation and cumulus expansion (GDF9, BMP15, HAS2, TNFAIP6, FGF17 and FSHr) following two standard methods of bovine COCs vitrification.Methods
Bovine cumulus-oocyte complexes (COCs) were aspirated from slaughtered ovaries and then distributed into three groups: non-vitrified COCs (control), vitrification 1 group (V1); vitrification was performed by 15% ethylene glycol (EG) and 15% DMSO in holding media (TCM-199 with 20% FCS); and vitrification 2 group (V2); vitrification was performed by 40% EG in holding media. After vitrification, COCs were warmed in two steps and cultured and then evaluated for nuclear maturation, embryo development and gene expressions.Results
The mean (±SD) percentages of nuclear maturation and blastocyst/cleaved were higher in control group (79.5 ± 8.0 and 31.0 ± 5.1%) than the V1 (34.8 ± 9.1 and 4.4 ± 5.1%) and V2 (47.8 ± 11.7 and 7.1 ± 5.8%) groups (P < 0.05), respectively. Further, COCs in V2 group showed higher mean (±SD) percentages of cleavage compared to V1 group (31.8 ± 1.0 vs 21.7 ± 2.8%; P < 0.05). GDF9 and BMP15 expression levels were higher in COCs in the control than of the vitrification groups (P < 0.05). In addition, expression level of GDF9 and BMP15 was higher in V2 group than in V1group (P < 0.05). The expression of HAS2 and FGF17 in V1 group was lower (P < 0.05) than that of the V2 groups.Conclusions
Expression of oocyte maturation genes was affected by vitrification procedure and conditions. Using EG alone for vitrification of bovine immature COCs, resulted in higher expression of GDF9, BMP15 and production of more in vitro matured and cleaved oocytes.22.
Crop breeders often have to consider multiple traits for selecting and advancing superior genotypes. Under such circumstances, use of selection indices is considered superior to other selection approaches, such as tandem selection and independent culling. While many types of selection indices have been developed (e.g., Smith and Hazel index, Desired gain index, Brim index, and Robinson index), programs for computing some of them (e.g., Desired gain index, Brim index, and Robinson index) are not available. We have developed a comprehensive SAS (Statistical Analysis System) code to compute the following indices: Smith and Hazel index, Desired gain index, Brim index, and Robinson index. The program also computes efficiency and genetic gain associated with these indices. The computer program reported here is named Shiri-SAS-Index-Selection, which is simple and easy to use. We present examples of SAS output generated by the Shiri-SAS-Index-Selection program for two breeding strategies. The program can be accessed here. 相似文献
23.
Omid Reza Zandvakili Elnaz Ebrahimi Masoud Hashemi Parisa Akbari 《Communications in Soil Science and Plant Analysis》2017,48(19):2246-2255
The objectives of this greenhouse experiment were to quantify the benefits of green manure (GM) diversity and to assess effect of GM on a succeeding lettuce crop. Species included barley (B), field pea (P), sunn hemp (S), and buckwheat (U). Treatments included single plantings of B and P and mixtures of B and P (BP), B, P, and S (BPS), and B, P, S, and U (BPSU). The pea GM had the highest shoot concentration of potassium, calcium, magnesium, manganese, zinc, and iron. Roots had higher concentrations of nutrients than shoots. Accumulation of nutrients in legumes was higher than in barley. The CO2 flux from the soil suggests that the most intensive mineralization period occurred within two weeks after incorporation of GMs. The mixtures and single planting of P mixtures had a significant benefit over single planting of B regarding fresh and dry weight of the lettuce. 相似文献
24.
The present study investigated the effect of arginine on seminal plasma composition in rainbow trout. Male rainbow trout broodstocks (2500 ± 200 g) were fed five practical diets (each consisting of three triplicates) supplemented with Arginine at 0.50%, 1.50% and 2.00%. The control group were fed without arginine. Broodstock feeding lasted for 90 days, and then fish semen was sampled. Results indicated no significant differences in LDH, ALP, Fe2+ and phosphorous content among the different treatments. The lowest levels of AST and ALT and the highest levels of Ca2+ and Mg2+ ions were observed in the treatment fed with 1.50% arginine, which showed significant differences from other treatments (P < 0.05). Moreover, the amount of Cl?, Na+ and K+ ions was significantly increased in the seminal plasma in fish fed diets containing arginine in comparison with the control. As the amount of arginine was increased, the levels of uric acid became significantly greater in contrast to urea and glucose levels. The highest amounts of cholesterol, fructose and total protein were observed in treatments fed on 2.00%, 0.50% and 1.00% arginine, respectively, showing significant differences from other treatments (P < 0.05). The highest pH value was assayed in the 1.50% arginine treatment. Results indicated that arginine had a potential efficacy on semen quality in rainbow trout broodstocks. 相似文献
25.
Salehizadeh Mandana Modarressi Mohammad Hossein Mousavi Seyed Naser Ebrahimi Maryam Tajabadi 《Tropical animal health and production》2019,51(8):2279-2286
The effects of screened lactic acid bacteria strains were evaluated on growth performance, humoral immunity, and IGF-1 gene expression in broiler chickens. The three dietary groups of negative control fed basal diet, the native LAB probiotic group (NP), and PrimaLac commercial LAB probiotic (PC) were studied. The results revealed that NP and PC diets significantly improved feed conversion ratio and increased body weight, as well as relative weight of carcass compared with group fed NC diet (P?<?0.05). Lymphocyte level was significantly increased in birds fed NP and PC (P?<?0.01), while serum triglycerides and total cholesterol levels were significantly decreased compared with the NC (P?<?0.05). Significant increases were observed in antibody titers against Newcastle disease virus of vaccinated birds (P?<?0.03), and morphological analysis of ileum revealed significant increases (P?<?0.05) in the villus height and villus height/crypt depth in birds fed NP and PC compared with the NC. The dietary significantly increased Lactobacillus spp. (P?<?0.05), while Escherichia coli (P?<?0.04) populations were significantly decreased, and also, the expression of IGF-1 gene in liver tissue of broilers fed NP and PC was significantly increased compared with the NC (P?<?0.05). These results indicated that the identified native LAB strains can be used commercially as a low-cost probiotic in poultry industry of Iran.
相似文献26.
Double‐sampling, as a cost‐effective and sufficiently accurate method, is an acknowledged method for estimating herbage mass at the level of the plant species up to the total plant community. It was investigated whether adjusting visual estimations of double‐sampling is applicable at different levels of species aggregation when different seasons and habitats are involved. The method was used in six different habitats of the same ecosystem, a grassland nature reserve in western Belgium, based on eight sampling periods. A general linear model was used to analyse the data at four levels of species aggregation. The correlation between estimated and measured values of herbage mass was significant for the majority of graminoid species at the levels of the sub‐life‐form and total plant community but not at the level of the life‐form. Interaction of habitat type and measured herbage mass, and interaction of date and measured herbage mass, were significant for a minority of species. A significant interaction of both date and habitat with measured herbage mass was found in some cases at the level of the sub‐life‐form and total plant community. Results suggest that the double‐sampling method is reliable for most graminoids and at the sub‐life‐form level, but should be applied more cautiously for forbs species, and when different sampling periods and habitat types are involved at the level of the life‐form. To avoid producing several calibration lines at the level of the species and to overcome deficiency of observations at this level, lumping morphologically similar species from the same vegetation stratum in sub‐life‐form groups is recommended for adjusting estimated herbage mass. 相似文献
27.
Phytoparasitica - Metschnikowia pulcherrima alone and in combination with methyl jasmonate [MeJA] was applied for control of blue mold of apple caused by Penicillium expansum. In vitro, MeJA at... 相似文献
28.
A. Negahi A. Sarrafi A. Ebrahimi P. Maury J. M. Prospéri C. Ben M. Rickauer 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(1):135-143
Verticillium wilt caused by Verticillium albo-atrum and Verticillium dahliae is responsible for yield losses in many economically important crops. The capacity of pathogenic fungi to adapt to new hosts is a well-known threat to the durability of resistant crop varieties. In the present work, 25 Medicago truncatula genotypes from a core collection and six V. albo-atrum and V. dahliae strains were used to study the potential of non-host Verticillium strains isolated from different plant species to infect this legume plant and the plant’s susceptibility to the pathogens. The experiment was designed as factorial with randomised complete blocks and with three repetitions. The wilt symptoms caused by V. albo-atrum and V. dahliae were scored on a disease index scale from 0 to 4, during 30 days after inoculation of 10-day-old plantlets. Disease severity was quantified by maximum symptom scores (MSS) and areas under the disease progress curves (AUDPC), which integrate the time course of symptom development. Highly significant differences were observed among plant genotypes and fungal strains, and their interaction was also significant. The correlation between MSS and AUDPC was 0.86. The most severe symptoms were caused by the alfalfa strain V. albo-atrum V31-2 and the least severe by V. dahliae JR2, as shown by mean values obtained on the 25 genotypes. M. truncatula genotype TN8.3 was the most susceptible genotype by mean values obtained with the six fungal strains, whereas F11013-3, F83005.9 and DZA45.6 were highly resistant to all strains studied. The results can be used to choose parents for studying the genetics of resistance in Medicago truncatula to Verticillium strains with different levels of aggressiveness. 相似文献
29.
Finite element analysis of stress and strain distributions in mortise and loose tenon furniture joints 总被引：1，自引：0，他引：1
We studied the effect of loose tenon dimensions on stress and strain distributions in T-shaped mortise and loose tenon （M＆amp;LT） furni-ture joints under uniaxial bending loads, and determined the effects of loose tenon length （30, 45, 60, and 90 mm） and loose tenon thickness （6 and 8 mm） on bending moment capacity of M＆amp;LT joints constructed with polyvinyl acetate （PVAc） adhesive. Stress and strain distributions in joint elements were then estimated for each joint using ANSYS finite element （FE） software. The bending moment capacity of joints increased significantly with thickness and length of the tenon. Based on the FE analysis results, under uniaxial bending, the highest shear stress values were obtained in the middle parts of the tenon, while the highest shear elastic strain values were estimated in glue lines between the tenon sur-faces and walls of the mortise. Shear stress and shear elastic strain values in joint elements generally increased with tenon dimensions and corre-sponding bending moment capacities. There was consistency between predicted maximum shear stress values and failure modes of the joints. 相似文献
30.
M. Ebrahimi A. Zare Shahneh M. Shivazad Z. Ansari Pirsaraei M. Tebianian C. A. Ruiz-Feria 《British poultry science》2014,55(1):81-88
1. Reducing excess fat accretion is important for both human health and animal production. The present study was conducted to investigate the effects of arginine (Arg) on the regulation of lipogenic gene expression and on growth performance.
2. One-d-old female broiler chicks (Ross, n = 192) were used in a completely randomised design with 4 dietary treatments in which diets included 100% (CTL), 153% (LArg), 168% (MArg) and 183% (HArg) of the recommended concentration of digestible Arg.
3. Results showed that high concentrations of Arg improved body weight gain, feed efficiency, meat production, fat and crude protein content of breast muscle and plasma thyroid hormones. Conversely, abdominal fat, cholesterol, triglyceride and urea were lower with higher concentrations of Arg. Dietary arginine increased lipogenic gene expression in muscles, while decreasing those in adipose tissue and liver.
4. It was conclded that increasing Arg in the diet reduced abdominal fat content, enhanced intramuscular fat and increased muscle and protein gain. Furthermore, Arg supplementation at the MArg concentration improved growth performance, and at HArg had the greatest effect on fat reduction. 相似文献