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排序方式: 共有253条查询结果,搜索用时 15 毫秒
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Bijan Soleymani Kamran Mansouri Mohsen Rastegari-Pouyani Shahram Parvaneh Fatemeh Khademi Mehdi Sharifi Tabar Ali Mostafaie 《Reproduction in domestic animals》2021,56(2):270-277
Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms. 相似文献
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Free‐floating macrophytes are often common in standing water bodies. Fishponds are suitable medium for Azolla growth; however, it rapidly self‐propagates and doubles its biomass in a few days and could strongly influence nutrient dynamics. The preference of Tilapia zillii (Gervais) to consume the free‐floating plant, Azolla pinnata, was tested in two experiments. In the first experiment, fish with different initial body weights (2–3 g, 7–10 g, 15–20 g, and 50–60 g) were randomly distributed at a rate of 150 ± 5 g/100‐L aquarium and fed fresh A. pinnata for 8 wk. A known weight of fresh plant was given to fish; after 24 h, Azolla remaining in aquaria was collected, dried with tissue paper, and reweighed to determine amount consumed. In the second experiment, fish were fed one of five diets containing different levels of dry Azolla meal as replacements of the control diet (20% crude protein) at levels of 0 (control), 25, 50, 75, or 100% for 13 wk. Growth retardation and weight loss were observed in all fish sizes fed fresh Azolla, and the mortality rates were 53.3–56.7%. The consumption of fresh Azolla decreased over time up to the eighth week; otherwise, Azolla consumption was fish size dependent. Whole‐body contents of crude protein decreased significantly, while total lipids and ash contents increased significantly with increasing fish size. In the second experiment, fish growth was reduced when the level of dry Azolla meal in the diet exceeds 25%. The mortality rate increased significantly with increasing Azolla level in the diet. Carcass composition showed increases in moisture and ash contents and decreases in dry matter, crude protein, and total lipids with the increase of Azolla level in the diets. Amount of diet consumed decreased, while feed conversion ratio increased significantly with the increase in dry Azolla level in the diet. Moreover, protein efficiency ratio, protein productive value, and energy utilization decreased significantly with the increase in dry Azolla level in the diet. It could be concluded that the preference of T. zillii to consume Azolla plants inhabiting water bodies is limited, but it could partially consume the dry Azolla meal at low and moderate levels. The optimum inclusion level of dry Azolla meal should be no more than 25% in T. zillii diet. 相似文献
4.
Abdel-Tawwab Mohsen Eissa El-Sayed Hemdan Tawfik Wesam A. Abd Elnabi Heba E. Saadony Saadea Bazina Walaa K. Ahmed Ragaa A. 《Fish physiology and biochemistry》2022,48(3):585-601
Fish Physiology and Biochemistry - The current study investigated the effects of dietary curcumin nanoparticles (C-NPs) on the performance, hemato-biochemical profile, digestive enzymes activities,... 相似文献
5.
Morteza Pourreza Seyed Mohsen Hosseini Ali Akbar Safari Sinegani Mohammad Matinizadeh Seyed Jalil Alavai 《林业研究》2014,25(1):113-120
Zagros forests are mainly covered byQuercus brantii L. coppices and oak sprout clumps occupy the forest area like patches. We investigated post-fire herbaceous diversity in the first growing season after fire. For this purpose neighboring burned and unburned areas were selected with the same plant species and ecological conditions. The data were collected from areas subjected to different fire severities. Overall 6 treatments were considered with respect to fire severity and the mi-crosites of inside and outside of oak sprout clumps including: unburned inside and outside of sprout clumps (Ni and No), inside of sprout clumps that burned with high fire severity (H), inside of sprout clumps that burned with moderate fire severity (M), outside of sprout clumps that burned with low fire severity (OH and OM). Different herbaceous com-position was observed in the unburned inside and outside of oak sprout clumps. The species diversity and richness were increased in treatments burned with low and moderate fire severity. However, in treatment burned with high fire severity (H), herbaceous cover was reduced, even-ness was increased, and richness and diversity were not significantly changed. We concluded that besides the microsites conditions in forest, fire severity is an inseparable part of the ecological effect of fire on her-baceous composition. 相似文献
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Mohsen Dadar Saeid Ansari Mahyari Mohammad Rokouei Mohammd Ali Edriss 《Animal Science Journal》2014,85(10):888-894
The accumulation of inbreeding and the loss of genetic diversity is a potential problem in Holstein dairy cattle. The goal of this study was to estimate inbreeding levels and other measures of genetic diversity, using pedigree information from Iranian Holstein cattle. Edited pedigree included 1 048 572 animals. The average number of discrete generation equivalents and pedigree completeness index reached 13.4 and 90%, respectively. The rate of inbreeding was 0.3% per year. Effective number of founders, founder genomes, non‐founders and ancestors of animals born between 2003 and 2011 were 503, 15.6, 16.1 and 25.7, respectively. It was proven that the unequal founder contributions as well as bottlenecks and genetic drift were important reasons for the loss of genetic diversity in the population. The top 10 ancestors with the highest marginal genetic contributions to animals born between 2003 and 2011 and with the highest contributions to inbreeding were 48.20% and 63.94%, respectively. Analyses revealed that the most important cause of genetic diversity loss was genetic drift accumulated over non‐founder generations, which occurred due to small effective population size. Therefore, it seems that managing selection and mating decisions are controlling future co‐ancestry and inbreeding, which would lead to better handling of the effective population size. 相似文献
8.
Naghmeh Daneshvar Hakimi Maibodi Mohsen Kafi Farhad Rejali 《Journal of plant nutrition》2015,38(2):224-236
In recent years, applying humic acid (HA) has been common in turfgrass management. A series of experiments were conducted to evaluate the effect of HA on qualitative and quantitative characteristics of “Speedygreen” perennial ryegrass (Lolium perenne L.). Different concentrations of HA (0, 100, 400, and 1000 mg L?1) were applied monthly as foliar application. Results showed that leaf phosphorus (P), potassium (K), and zinc (Zn) content, fresh and dry weight, chlorophyll content, and root fresh weights were not affected by HA. Meanwhile, HA improved the root and shoot development, except for root fresh weight. While just 100 mg L?1 improved height, visual quality, nitrogen (N) content, roots length, and surface of roots, all of HA concentrations were effective on iron content. These results suggest that HA foliar application might be of benefit to enhance some nutrients uptake and root development of ryegrass possibly leading to improved drought resistance. 相似文献
9.
Prolific and rapid in vitro plant organogenesis via direct regeneration has been obtained from axenic seedling-derived petiole and leaf explants of Ficus religiosa in Murashige and Skoog (MS) medium containing different concentrations of cytokinins in combination with indole-3-butyric acid (IBA). MS medium with 1.5 mg/l 6-benzylaminopurine plus 0.15 mg/l IBA produced the highest shoot induction frequency with an average of 6.26 and 10.13 shoots per leaf and petiole explants, respectively. After 4 weeks, the highest root formation frequency (96.7%), root number (5.73), and root length (4.76 cm) were with MS medium containing 2.0 mg/l IBA plus 0.1 mg/l α-naphthalene acetic acid. In addition, the effect of four sodium nitroprusside (SNP) treatments on acclimatization was also studied. Highest morphological traits such as survival rates, fresh and dry root weights as well as antioxidant enzymatic activities such as superoxide dismutase, peroxidase, and catalase was achieved with 125 ppm SNP. The α-amino acid, proline, content was highest with this treatment while the highest H2O2 (hydrogen peroxide) was in the controls. This study introduces a cost-effective, prolific, and efficient in vitro multiplication system to supply pharmaceutical and ornamental needs. It is the first report of an in vitro organogenesis protocol for F. religiosa by direct regeneration through axenic seedling-derived petiole and leaf explants, which can be efficiently employed for the utilization of active biomolecules. 相似文献
10.
Maryam Haghighi Mohsen Kafi Atena Sheibanirad Mohammad Reza Sharifinia 《Journal of plant nutrition》2016,39(10):1460-1471
Ornamental kale (Brassica oleracea var. Acephala) is usually planted from early autumn until late winter. Since most of the plants used for phytoremediation cannot be grown during this time, kale can be a suitable option for phytoremediation and utilized during autumn and winter in urban landscape, especially in metropolitan areas where high levels of cadmium (Cd) and lead (Pb) pollutions exist. Kale growth in saline soil at different growth stages (germination and vegetative growth stages) was studied in this investigation. A factorial experiment based on completely randomized design (CRD) with four replications was used in this study. Treatments included three levels of sodium chloride (NaCl) (0, 30, and 60 mg/kg), four levels of Cd (0, 4, 8, and 16 mg/kg), and four levels of Pb (0, 1, 5, and 10 mg/kg). Results indicated that increase in Cd and Pb concentrations in the soil decreased fresh and dry weights of the plants. The results of the various growth stages revealed that under salinity stress, kale plants were able to absorb more Pb than Cd and effectively remediate Pb in polluted and saline lands. Cd accumulation in control treatment was 6.2% more than that in the saline treatments, whereas, Pb accumulation in the highest NaCl level, 60 mg/kg salinity treatment was 7.64% more than that of the control condition. Also, proline content of the plants was significantly increased under Cd and Pb stress. From the results of this study, it was concluded that using kale plant is recommended for phytoremediation of saline soils with 10 and 16 mg/kg Pb and Cd contents, respectively. 相似文献