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Effects of Microbial Fermented Feed on Growth and Development of Farmed Crayfish
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作者 Qu Chunjuan Song Guangtong 《Animal Husbandry and Feed Science》 CAS 2024年第1期47-51,共5页
Microbial fermented feed possesses a natural fermentation flavor and exhibits good palatability.It is not only easily digestible and absorbable by livestock but also non-toxic.Additionally,it has the capacity to inhib... Microbial fermented feed possesses a natural fermentation flavor and exhibits good palatability.It is not only easily digestible and absorbable by livestock but also non-toxic.Additionally,it has the capacity to inhibit the proliferation of pathogenic bacteria,facilitate the growth and development of animals,and enhance their immune response,disease resistance,and overall production performance.This paper summarizes the selection of common feed materials and microbial strains used in fermented feed,as well as their effects on the growth performance,muscle quality,antioxidant capacity,and immune function of crayfish.The aim of this study is to provide a reference for the further popularization and application ofmicrobialfermented feed in crayfishaquaculture. 展开更多
关键词 Microbial fermented feed CRAYFISH Muscle quality growth and development Influence mechanism
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Effects of Water-retaining Agents on Growth, Development, Yield and Quality of Soybean under Drought Stress
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作者 Hui XIA Yan ZHANG +2 位作者 Yun HAN Shasha HU Hengbin ZHANG 《Plant Diseases and Pests》 2024年第3期34-39,共6页
[Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effect... [Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effects of drought stress(MDS)and drought stress with low(MDS-L),medium(MDS-M)and high doses(MDS-H)of the water-retaining agent on the growth and development indicators,root activity,MDA content,antioxidant enzyme activity,yield and quality of soybean were studied by field plot test,with the normal water supply serving as the control(CK).[Results]In response to drought stress,the plant height,stem diameter,and yield of soybean exhibited a notable decline.Additionally,the contents of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a significant reduction.Conversely,the root activity and antioxidant enzyme activity exhibited a noticeable decline,while the MDA content exhibited an increase.The application of varying doses of the water-retaining agent was found to significantly enhance soybean growth,stimulate root activity,and elevate antioxidant enzyme activity,while concurrently reducing MDA content.The observed effects were found to be dose-dependent,with the greatest effects observed at the highest dose.In comparison to MDS,the yields of soybean in the MDS-L,MDS-M,and MDS-H treatments exhibited a 18.38%,25.58%,and 46.26%increase,respectively.Additionally,the content of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a notable enhancement.[Conclusions]The application of the water-retaining agent has been demonstrated to significantly promote the growth of soybean plants under conditions of drought stress,resulting in an improvement in both the yield and the quality of the soybean crop.The recommended dosage of the water-retaining agent is 3.3 kg/667 m 2. 展开更多
关键词 SOYBEAN Water-retaining agent YIELD Quality growth and development Antioxidant enzyme activity
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Curriculum Development and Teachers for Cultivating OECD Student Agency in Japan:From an Examination of Educational Thought,Educational System,History,and Contemporary Science and Mathematics Education Practices
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作者 Kenji Shigeno 《Cultural and Religious Studies》 2024年第8期488-500,共13页
The purpose of this paper is to examine the development of a curriculum in Japan to foster the agency(OECD Student Agency)necessary for children living in the future,as outlined in the OECD Education2030 Project,and t... The purpose of this paper is to examine the development of a curriculum in Japan to foster the agency(OECD Student Agency)necessary for children living in the future,as outlined in the OECD Education2030 Project,and the role of teachers who implement this curriculum.Therefore,I aim to achieve this goal by taking an overview of educational thought,educational systems and history,and examining several initiatives in the OECD Project and the situation of a Japanese high school that practices science and mathematics education.As a result of analyzing previous research and the narratives obtained from interviews with Teacher A(pseudonym)of a certain F High School(pseudonym),it was found that school education should not simply teach subjects,but should aim to enable student to help student exercise agency in the future.It was suggested that it is not necessary to add content to the curriculum,but rather to prepare to provide students with competencies that will enable them to use the content in various contexts,situations,and circumstances,suggesting that in order to discover such important competencies,teachers and other related parties are required to implement curricula that allow students to slowly and carefully explore the competencies surrounding the content,and to conceive and build curricula that include both hidden and intended curriculum that allows student to reflect on the curriculum they have achieved. 展开更多
关键词 OECD student Agency curriculum development teachers
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Assessment of growth monitoring among children younger than 5 years at early childhood development centres in Nelson Mandela Bay,South Africa
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作者 Shawn W.McLaren Liana Steenkamp Jessica Ronaasen 《Health Care Science》 2024年第1期32-40,共9页
Introduction:Early childhood development(ECD)centres are important community hubs in South Africa and act as sites for community detection of childhood nutrition problems.This study aimed to assess the ability of trai... Introduction:Early childhood development(ECD)centres are important community hubs in South Africa and act as sites for community detection of childhood nutrition problems.This study aimed to assess the ability of trained ECD practitioners with optimal support to correctly classify the nutritional status of infants and young children at ECD centres in the Nelson Mandela Bay.Methods:A descriptive,cross-sectional study was used to collect data from 1645 infants and children at 88 ECD centres.Anthropometric measurements were taken by trained fieldworkers and growth monitoring and promotion infrastructure was audited at ECD centres.Results:Of the sample,4.4%(n=72)were underweight by weight for age Z-score(WAZ<-2)and 0.8%(n=13)were severely underweight(WAZ<-3).Results showed that 13.1%(n=214)were stunted by height for age Z-score(HAZ<-2)and 4.5%(n=74)were severely stunted(HAZ<-3).The prevalence of moderate acute malnutrition was 1.2%and severe acute malnutrition was 0.5%,while the prevalence of overweight was 9.2%and the prevalence of obesity was 4%.A significant level of agreement between the correct interpretation and the ECD practitioners'interpretation was observed across all the anthropometric indicators investigated.The true positive wasting cases had a mean mid-upper arm circumference(MUAC)of 14.6 cm,which may explain the high false negative rate found in terms of children identified with wasting,where ECD practitioners fail to use the weight for height Z-score(WHZ)interpretation for screening.Conclusion:By using ECD centres as hub to screen for malnutrition,it may contribute to the early identification of failure to thrive among young children.Although it was concerning that trained ECD practitioners are missing some children with an unacceptably high false negative rate,it may have been due to the fact that wasting in older children cannot be identified with MUAC alone and that accurate WFH plotting is needed.Onsite mentorship by governmental health workers may provide ECD practitioners with more confidence to screen children for growth failure based on regular WFH measurements.Moreover,ECD practitioners will be more confident to monitor the Road to Health booklets for missed vaccinations,vitamin A and deworming opportunities. 展开更多
关键词 early childhood development CHWs growth monitoring WASTING
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Construction of Guiding System for Growth and Development of College Students under the Student-oriented Concept
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作者 Shuzhen WANG Qing TANG 《Asian Agricultural Research》 2018年第5期89-91,共3页
The student-oriented concept is a kind of people orientation. It emphasizes respect and support for students. It is student-centered,and is for all students. At the school level,the guiding principles of student orien... The student-oriented concept is a kind of people orientation. It emphasizes respect and support for students. It is student-centered,and is for all students. At the school level,the guiding principles of student orientation and respecting teachers and teaching must be adhered to,and corresponding reforms in the school's system,policies and environment needs to be carried out. At the university teacher level,the concept of student orientation must be adhered to in teaching,and it is regarded as the guiding concept of teaching and education and is implemented in classroom teaching and practical teaching. At the level of college administrator,the concept of student orientation must be adhered in the course of daily management and service to do better management,service and education work. In order to better implement the student-oriented concept and promote the growth and development of college students,we needs to build a mentor team for college students' growth based on political workers,establish a team of academic tutors for college students based on professional teachers and build a platform for cooperation between schools and enterprises. The innovative training mode can promote students to grow into talents. 展开更多
关键词 student-oriented concept College students growth CONSTRUCTION
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Comparison of Growth and Development Traits among Crossbreds of Dorset and Local Sheep Varieties in Gansu Province 被引量:4
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作者 孙晓萍 刘建斌 +1 位作者 张万龙 冯瑞林 《Agricultural Science & Technology》 CAS 2016年第1期117-121,143,共6页
In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongoli... In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongolia sheep. The offspring of different crossbreeding combinations were sampled randomly at different growth stages, and their growth and development traits were measured so as to screen out the best crossbreeding mode. The results showed that under the same crossbreeding mode, the growth rate of F3 was higher than that of F2, and of F2 was higher than that of F1. Among the F3 population, the growth rates of Dorset ×Han and Dorset × Mongolia hybrids were higher. Compared with those of Dorset ×Tan F3 hybrids, the body weights of male and female Dorset × Han and Dorset ×Mongolia F3 hybrids were increased by 5.59%, 4.40%, 5.93% and 3.76%, respectively. Among the F2 population, the growth rates of Dorset × Han and Dorset ×Mongolia hybrids were also higher. The body weights of male and female Dorset ×Han and Dorset × Mongolia F2 hybrids were higher than those of Dorset × Tan ×Han F2 hybrids by 5.99%, 3.67%, 9.80% and 5.00%, respectively. In the F1 population, the growth rates of Dorset × Han and Dorset × Mongolia hybrids were higher.Compared with those of Tan × Han F1 hybrids, the body weights of male and female Dorset × Han and Dorset × Mongolia F1 hybrids were increased by 11.32%,5.22%, 7.60% and 7.20%, respectively. Therefore, in the feeding area of Small Tai Han sheep, Mongolia sheep and Tan sheep, Dorset was the best sire for producing hybrid lambs. The economic benefit of crossbred offspring was obvious. 展开更多
关键词 DORSET Mongolia sheep Small Tail Han sheep Tan sheep Crossbreeding combination growth and development
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Dynamic Characteristics of Growth and Development of Xiangsha Taro in Jingjiang 被引量:2
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作者 殷剑美 韩晓勇 +3 位作者 王立 张培通 郭文琦 李春宏 《Agricultural Science & Technology》 CAS 2014年第3期375-378,共4页
The growth and development of Jingjiang Taro [Colocasia esculenta(L.) Schott] were observed, laying foundation for highly-yielding cultivation technology system of Xiangsha taro. The results indicate that germinatio... The growth and development of Jingjiang Taro [Colocasia esculenta(L.) Schott] were observed, laying foundation for highly-yielding cultivation technology system of Xiangsha taro. The results indicate that germination of the second taro happened from 46 d after sprouting (7-8 leaves); the first taro began to expand, from 125 d after sprouting (12 leaves) when the the second taro was been formed; the third taro began to form from 141 to 150 d after sprouting (15-16 leaves). The fresh weight of the second and third taros quickly increased from the time of 15 leaves to harvest. Early September is a transformation term of Xiangsha taro from vegetative body dominant to corm growth dominant. 展开更多
关键词 Xiangsha taro in Jingjiang growth and development Dynamic charac- teristics Cultivation technology
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Effects of Nitrogen Application Amount on Growth Characteristics,Boll Development and Lint Yield of High Quality Cotton 被引量:1
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作者 周桂生 林岩 +2 位作者 童晨 安琳琳 刘贵娟 《Agricultural Science & Technology》 CAS 2011年第11期1667-1670,共4页
[Objective] This study aimed to explore an optimum application amount of nitrogen for cotton cultivation. [Method] In this study, a field experiment was conducted to investigate the effects of nitrogen application amo... [Objective] This study aimed to explore an optimum application amount of nitrogen for cotton cultivation. [Method] In this study, a field experiment was conducted to investigate the effects of nitrogen application amount on the growth characteristics, boll development and lint yield of high quality cotton line FZ-1. [Result] Compared with the nitrogen level of 225 kg/hm2, the lint yield had increased by 28.46% and 18.73%, respectively, with the nitrogen application amount of 300 and 375 kg/hm2. When the nitrogen application amount had increased from 225 to 300 kg/hm2, boll number per plant, boll weight and lint yield had significantly increased. At the nitrogen level of 375 kg/hm2, however, the effects of increasing lint yield were significantly less than that at the nitrogen level of 300 kg/hm2. Compared with the nitrogen levels of 225 and 375, 300 kg/hm2 of nitrogen was the optimum application amount to improve the plant height, daily increment of plant height, number of fruit branches, number ratio of nodes to fruit branches, boll volume and seed cotton weight per boll. [Conclusion] The rational management of nitrogen is the most effective way to promote the growth and development of cotton plants, ensure high yielding ability and minimize the environmental pollution caused by the overuse of nitrogen. This study had provided a sound nitrogen application strategy for the cultivation of this high-quality cotton line in the field plantation. 展开更多
关键词 Nitrogen application amount growth characteristics Boll development Lint yield
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Effects of Light Intensity on Growth, Development and Formation on Fagopyrum cymosum 被引量:1
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作者 华劲松 戴红燕 《Agricultural Science & Technology》 CAS 2014年第3期363-366,共4页
Effects of light intensity on growth, development and formation on Fagopy- rum cymosum were explored with natural light intensities at 100%(A), 85.2%(B), 75.8%(C) and 59.7%(D). The results showed that the decl... Effects of light intensity on growth, development and formation on Fagopy- rum cymosum were explored with natural light intensities at 100%(A), 85.2%(B), 75.8%(C) and 59.7%(D). The results showed that the decline of light intensity re- duced nutrient growth period, so that plant growth stage entered in advance and extended, which indicated that the decline of light intensity would lower leaf number and area, the number of twigs from the stem, as well as photosynthate. Further- more, the reduction degree increased upon light intensity decrease degree, and the proper shading improved stem height and leaf area enhanced before growth term. 展开更多
关键词 Fagopyrum cymosum Light intensity growth and development Morpho- logical characters
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Study on Growth and Development Rules and Growth Curve Fitting of Minghua Black Minks
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作者 荣敏 涂剑锋 +3 位作者 张志明 王淑茗 高峰 邢秀梅 《Agricultural Science & Technology》 CAS 2017年第2期285-286,302,共3页
Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very w... Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very well by Logistic model and Gompertz model (the degree of fitting FF≥0.99), but Gompertz model was better at fitting and predicting their weight. 展开更多
关键词 Minghua black minks growth curve Non-lineared models development rules FITTING
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The Impact of Lead Stress on Growth and Development of Two Varieties of Wheat
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作者 杨生龙 康建宏 吴宏亮 《Agricultural Science & Technology》 CAS 2010年第9期171-174,共4页
[Objective] This study was to explore the impact of lead stress on growth of wheat.[Method]Taking two wheat varieties Ningchun No.13 and Ningchun No.4 as experimental materials,the growth and development of wheat unde... [Objective] This study was to explore the impact of lead stress on growth of wheat.[Method]Taking two wheat varieties Ningchun No.13 and Ningchun No.4 as experimental materials,the growth and development of wheat under the stress of different concentration of stress was studied using potting method.[Result]With the increase of externally applied Pb,the plant height of two wheat varieties tested assumed a falling trend.When stressed by low concentration of Pb(lower than 200 mg/kg),the fresh weight and dry weight of both varieties rose with the increase of Pb concentration;however,once exceeded 200 mg/kg,they totally showed a decline trend.Under a same fertilization level,root-stalk ratios of Pb-stressed-plants of two varieties were lower than that normally grown,of two varieties Ningchun No.13 performed better than Ningchun No.4.Higher concentration of Pb(200-800 mg/kg)severely blocked the physiological-chemical activity of both wheat varieties,which hindered the accumulation of N,P and K.[Conclusion]Our results provided theoretical basis for taking reasonable cultivation countermeasures for the Pb-polluted paddy field. 展开更多
关键词 PB WHEAT growth and development NUTRIENT
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Study on Growth and Development and Dry Matter Production of Greenhouse Tomato in North China
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作者 王停停 温祥珍 +2 位作者 张玲 袁婷婷 李亚灵 《Agricultural Science & Technology》 CAS 2016年第7期1638-1641,1713,共5页
[Objective] This study aimed to investigate the growth and development and dry matter production and allocation of greenhouse tomato in North China. [Method] With tomato cultivar 'Jinguo No.l' as the experimental ma... [Objective] This study aimed to investigate the growth and development and dry matter production and allocation of greenhouse tomato in North China. [Method] With tomato cultivar 'Jinguo No.l' as the experimental material, the ex- periments were conducted in a solar greenhouse located in Taigu, Shanxi (37o25' N, 112o25' E) from March to July, in 2014 and 2015. [Result] The plant height, leaf number, leaf area and dry matter production of greenhouse tomato increased lin- early with the increased days after transplantation, and their growth rates were 2.74 cm/d, 0.32 leaf/d, 70 cm2/d and 9.4 g/(m2.d), respectively. The fruit dry weight also showed a linear relationship with the plant dry weight. After fruit setting, the fruit dry weight was increased by about 0.69 g when the plant dry weight was increased by 1 g. The allocation proportions of dry matter in tomato roots, stems and leaves de- clined significantly from plant flowering to fruiting, while the proportion of fruit dry weight in plant dry weight increased significantly, exceeding 60%. There was a strong linear relationship between dry matter production of tomato and effective cu- mulative temperature (sum of temperature higher than 10 ^(3) in the solar green- house, and the dry matter production was increased by about 0.73 g/m2 when the effective cumulative temperature was increased by one unit. The dry matter produc- tion of tomato plant also showed a strong linear relationship with photosynthetic ac- tive radiation (PAR) in the greenhouse, and about 3.4 g of dry matter was synthe- sized per unit (M J) of PAR. [Conclusion] Extending the growing period and improv- ing the temperature and light conditions could increase the dry matter production of tomato. 展开更多
关键词 Solar greenhouse TOMATO growth and development Dry matter alloca- tion
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Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas 被引量:1
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作者 ZHANG Yunping LIN Jianping +3 位作者 HUANG Yimin CHEN Zebin ZHU Chenhui YUAN Hao 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1647-1662,共16页
With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control ... With rapid economic development,the size of urban land in China is expanding dramatically.The Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban sprawl.Reasonable delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the city.It is of practical significance for the construction of green urban space.The study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)model.At the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final UGB.The results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability score.The results of convex hull model show that the urban expansion type of Nankang is epitaxial.In the future,the urban expansion will mainly occur in the northern part of the city.The PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated UGB.The final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study area.The results of the delineation can promote sustainable urban development,and the delineation methodology can provide a reference basis for the preparation of territorial spatial planning. 展开更多
关键词 Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development
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Effects of different forms of yeast Saccharomyces cerevisiae on growth performance,intestinal development,and systemic immunity in early-weaned piglets 被引量:17
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作者 Zongyong Jiang Shaoyong Wei +8 位作者 Zhilin Wang Cui Zhu Shenglan Hu Chuntian Zheng Zhuang Chen Youjun Hu Li Wang Xianyong Ma Xuefen Yang 《Journal of Animal Science and Biotechnology》 CAS CSCD 2016年第1期78-85,共8页
The present study was conducted to determine effects of different forms of yeast (Saccharomyces cerevisiae, strain Y200007) on the growth performance, intestinal development, and systemic immunity in early-weaned pi... The present study was conducted to determine effects of different forms of yeast (Saccharomyces cerevisiae, strain Y200007) on the growth performance, intestinal development, and systemic immunity in early-weaned piglets. A total of 96 piglets (14-d old, initial average body weight of 4.5 kg) were assigned to 4 dietary treatments: (1) basa diet without yeast (Control); (2) basal diet supplemented with 3.00 g/kg live yeast (LY); (3) basal diet supplemented with 2.66 g/kg heat-killed whole yeast (HKY); and (4) basal diet supplemented with 3.00 g/kg superfine yeast powders (SFY). Diets and water were provided ad libitum to the piglets during 3-week experiment. Growth performance of piglets was measured weekly. Samples of blood and small intestine were collected at days 7 and 21 of experiment. Dietary supplementation with LY and SFY improved G:F of piglets at days ]-21 of the experiment (P 〈 0.05) compared to Control group. Serum concentrations of growth hormone (GH), triiodothyronine (T3), tetraiodothyronine (T4), and insulin growth factor 1 (iGF-1) in piglets at day 21 of the experiment were higher when fed diets supplemented with LY and SFY than those in Control group (P 〈 0.05). Compared to Control group, contents of serum urea nitrogen of piglets were reduced by the 3 yeast-supplemented diets (P 〈 0.05). Diets supplemented with LY increased villus height and villus-to-crypt ratio in duodenum and jejunum of piglets (P 〈 0.05) compared to other two groups at day 7 of the experiment. Feeding diets supplemented with LY and SFY increased (P 〈 0.05) serum concentrations of IgA, IL-2, and IL-6 levels in piglets compared to Control. The CD4+/CD8+ ratio and proliferation of T-lymphocytes in piglets fed diets supplemented with LY were increased compared to that of Control group at day 7 of the experiment (P 〈 0.05). In conclusion, dietary supplementation with both LY and SFY enhanced feed conversion, small intestinal development, and systemic immunity in early-weaned piglets, with better improvement in feed conversion by dietary supplementation with LY, while dietary supplementation with SFY was more effective in increasing systemic immune functions in early-weaned piglets. 展开更多
关键词 growth performance IMMUNITY Intestinal development PIGLETS Saccharomyces cerevisiae YEAST
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Studies on hybridization effects of different geographic populations of Chlamys farreri Ⅱ.The medium-term growth and development of Chlamys farreri populations from China and Russia and their reciprocal crosses 被引量:12
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作者 LiuXiaolin ChangYaqing +3 位作者 XiangJianhai LiFuhua LiuXianjie BrovkinaElenaPavlovna 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期255-264,共10页
Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultura... Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months). 展开更多
关键词 Chlamys farreri POPULATION HYBRIDIZATION medium-term growth and development HETEROSIS
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Effects of Salinity on Embryonic Development, Survival, and Growth of Crassostrea hongkongensis 被引量:9
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作者 HUO Zhongming WANG Zhaoping +5 位作者 LIANG Jian ZHANG Yuehuan SHEN Jianping YAO Tuo SU Jiaqi YU Ruihai 《Journal of Ocean University of China》 SCIE CAS 2014年第4期666-670,共5页
This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artific... This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artificial seawater at three different salinities(low, 15; medium, 23; and high, 30) to determine the optimum hatchery and nursery conditions for mass production of the seeds. Results showed that the percentage production of straight-hinged larvae from fertilized eggs was significantly lower at the high salinity than at the low- and medium-salinities(P < 0.05). The survival rates of larvae and juveniles differed significantly among the three salinity trials, with the highest survival rate observed at the low salinity(P < 0.05). The shell height of larvae was significantly larger at the low salinity than at the high and medium salinities from days 9 to 15(P < 0.05), whereas that of juveniles was significantly larger at the low salinity than at the high and medium salinities on day 70(P < 0.05). These results indicate that the larvae and juveniles of C. hongkongensis are tolerant to a wide range of salinities(15 to 30), but show better growth and survival at relatively low salinities. Thus, it is recommended to use relatively low salinities in hatchery and nursery systems for improved yields of C. hongkongensis. 展开更多
关键词 SALINITY embryonic development SURVIVAL growth Crassostrea hongkongensis
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Modified halloysite nanotubes reduce the toxic effects of zearalenone in gestating sows on growth and muscle development of their offsprings 被引量:3
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作者 Rui Gao Qingwei Meng +4 位作者 Jianan Li Min Liu Yuanyuan Zhang Chongpeng Bi Anshan Shan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2016年第4期570-578,共9页
Background: Zearalenone (ZEN) is an estrogenic mycotoxin that is primarily produced by Fusarium fungi and has been proven to affect the reproductive capacity of many species to varying degrees. The present experime... Background: Zearalenone (ZEN) is an estrogenic mycotoxin that is primarily produced by Fusarium fungi and has been proven to affect the reproductive capacity of many species to varying degrees. The present experiment was designed to study the maternal persistent effects of zearalenone toxicity in gestating sows on growth and muscle development of their offsprings, and the alleviation of zearalenone toxicity by modified halloysite nanotubes (MHNTs). Methods: Eighteen sows were fed with one of three dietary treatments that included the following: (1) a control diet, (2) a contaminated grain diet (with 50 % moldy corn, 2.77 mg/kg ZEN), and (3) a contaminated grain diet (with 50 % moldy corn, 2.76 mg/kg ZEN) + 1% MHNTs. Each sow was exclusively fed its experimental diets from 35 to 70 d of gestation at a total of 2 kg daily. Muscle samples were collected from six piglets per treatment at birth, weaning and finishing. Results: The results showed that feeding the sows with the ZEN-contaminated diets from 35 to 70 d of gestation decreased the ADG, ADFI and G:F of their offsprings (P 〈 0.05). The muscle fiber numbers in the newborn, weaning and growing-finishing pigs and the muscle fiber diameters at birth and weaning were also decreased by maternal ZEN exposure (P 〈 0.05). The expressions of IGF-I, IGF-II, Myf-5 and Mstn at birth and IGF-II, Pax7, Myf-5 and MyoD1 at weaning were altered by feeding gestating sows with ZEN-contaminated diets (P 〈 0.05). The MHNTs reduced most of the ZEN-induced toxic effects: the ADG and ADFI on growth performance, the muscle fiber numbers at weaning and finishing and the muscle fiber diameters at weaning (P 〈 0.05). The expression levels of IGF-II and Mstn in newborn piglets and IGF-II and Myf-5 in weaning piglets were also prevented by adding 1% MHNTs (P 〈 0.05). Conclusions: The present study demonstrated that the offsprings of sows fed with ZEN-contaminated diets from 35 to 70 day of gestation exhibited weakening on growth performance, physiological changes in their muscle fibers and alterations of mRNA expression in their muscle tissues, and also indicated that MHNTs prevented most of the ZEN- induced weakening in the muscle tissues. 展开更多
关键词 growth MHNTs Muscle development Offsprings SOWS ZEARALENONE
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STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFT-EYED FLOUNDER, PARALICHTHYS OLIVACEUS (T. et S.) 被引量:10
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作者 尤锋 刘静 +3 位作者 王新成 徐永立 黄瑞东 张培军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2001年第2期147-151,共5页
The early effects of chromosomal manipulation of eggs and sperm on the yields of triploid and gynogenetic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fertilized ... The early effects of chromosomal manipulation of eggs and sperm on the yields of triploid and gynogenetic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fertilized eggs at 0-2℃ for 45 minutes duration 5 minutes after fertilization, and the induced triploidy rates were 31.2%-50% and the relative hatching rates were 53.3%-99%. Gynogenetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0-2℃ for 45 minutes duration 5 minutes after fertilization. The induced gynogenetic diploid rates and the relative hatching rates were 94%-96% and 48.5%-68.5% respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae according to Student’s t test (α=0.05). The relationship between the early growth of the triploid experimental group larvae and that of gynogenetic diploid experimental group larvae was also studied. 展开更多
关键词 TRIPLOIDY gynogenetic diploid embryonic development early growth P. olivaceus
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Sequence Variations in the Bovine IGF-I and IGFBP3 Genes and Their Association with Growth and Development Traits in Chinese Beef Cattle 被引量:6
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作者 GAO Xue SHI Ming-yan +3 位作者 XU Xiu-rong LI Jun-ya REN Hong-yan XU Shang-zhong 《Agricultural Sciences in China》 CAS CSCD 2009年第6期717-722,共6页
The objective of this study was to determine the genotype effects of the bovine insulin-like growth factor Ⅰ (IGF-Ⅰ) and its binding protein 3 (IGFBP3) genes on growth and development traits in beef cows, includ... The objective of this study was to determine the genotype effects of the bovine insulin-like growth factor Ⅰ (IGF-Ⅰ) and its binding protein 3 (IGFBP3) genes on growth and development traits in beef cows, including 130 Chinese Simmental, 42 Nanyang, and 47 Luxi Yellow cattle. Sequence variations in the bovine IGF-Ⅰ and IGFBP3 genes were investigated by single strand conformation polymorphism (SSCP). SSCPs were detected in 6 fragments, which is the 5'-flanking region, the 2nd exon, the 5th exon, and the 5th intron of the IGF-1 gene, and the 2nd exon, the 3rd exon of the 1GFBP3 gene. Two polymorphisms, an A-to-G transition in the 2rid exon of the IGF-Ⅰ gene and a T-to-C transition in the 2rid exon of IGFBP3 gene were detected in 3 breeds. The allele frequencies of 2 polymorphisms were 0.0411 (A), 0.9589 (B), and 0.7237 (A), 0.2763 (B), respectively. These 2 loci were analyzed to associate with body weight, height at withers, body length, heart girth, rump width, and beef production index (BPI) at 0, 6, 12, 24, and 36-month old. The IGFBP3 locus was shown to be associated with rump width, heart girth at 24-month and 36-month. Animals with BB genotype had higher rump width (24.86 ± 0.47) cm at 24-month and (27.50 ± 0.63) em at 36-month. The heart girth was highest for the individuals with BB genotype (171.33 ± 1.84) cm and higher than those with AB genotype (166.68 ± 1.13) cm (P〈 0.05) at 36-month. 展开更多
关键词 beef cattle IGF-1 gene 1GFBP3 gene growth and development traits PCR-SSCP
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Plant growth and their root development after inoculation of arbuscular mycorrhizal fungi in coal mine subsided areas 被引量:19
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作者 Yinli Bi Yanxu Zhang Hui Zou 《International Journal of Coal Science & Technology》 EI 2018年第1期47-53,共7页
Coal mining often cause serious land degradation, soil erosion, and desertification affecting growth of the local vegetation, especially the roots. Arbuscular mycorrhizal fungi (AMF) inoculation is considered a pote... Coal mining often cause serious land degradation, soil erosion, and desertification affecting growth of the local vegetation, especially the roots. Arbuscular mycorrhizal fungi (AMF) inoculation is considered a potential biotechnological tool for mined soil remediation because mycorrhizal fungi could improve plant growth environment, especially under adverse conditions due to their good symbiosis. A field experiment was conducted to study the ecological effects of AMF (Funneliformis mosseae, Rhizophagus intraradices) on the growth of Amygdalus pedunculata Pall. and their root development in the regenerated mining subsidence sandy land. The reclamation experiment included four treatments: inoculation of Funneliformis mosseae (F.m), inoculation of Rhizophagus intraradices (R.i), combined inoculation of F.m and R.i and non-inoculated treatment. Root mycorrhizal colonization, plant height, crown width, soil moisture, root morphology and certain soil properties were assessed. The results showed that AMF improved the shoot and root growth of Amygdalus pedunculata Pall., and significantly increased root colonization after 1 year of inoculation. Available phosphorus content, activities of phosphatase as well as electrical conductivity in soil rhizosphere of all the three inoculation treatments were higher than that of the non-inoculated treatment. AMF increased the quantity of bacteria and fungi in soil rhizosphere compared with the non-inoculated treatment. Our study indicates that revegetation with AMF inoculum could influence plant growth and root development as well as soil properties, suggesting that AMF inoculation can be effective method for further ecological restoration in coal mine subsided areas. 展开更多
关键词 Arbuscular mycorrhizal fungi Plant growth Root development Soil remediation Amygdalus pedunculata Pall
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