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Recognition and rejection of foreign eggs of different colors in Barn Swallows
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作者 Kui Yan Wei Liang 《Avian Research》 SCIE CSCD 2024年第3期374-378,共5页
Brood parasitic birds lay eggs in the nests of other birds,and the parasitized hosts can reduce the cost of raising unrelated offspring through the recognition of parasitic eggs.Hosts can adopt vision-based cognitive ... Brood parasitic birds lay eggs in the nests of other birds,and the parasitized hosts can reduce the cost of raising unrelated offspring through the recognition of parasitic eggs.Hosts can adopt vision-based cognitive mechanisms to recognize foreign eggs by comparing the colors of foreign and host eggs.However,there is currently no uniform conclusion as to whether this comparison involves the single or multiple threshold decision rules.In this study,we tested both hypotheses by adding model eggs of different colors to the nests of Barn Swallows(Hirundo rustica)of two geographical populations breeding in Hainan and Heilongjiang Provinces in China.Results showed that Barn Swallows rejected more white model eggs(moderate mimetic to their own eggs)and blue model eggs(highly non-mimetic eggs with shorter reflectance spectrum)than red model eggs(highly nonmimetic eggs with longer reflectance spectrum).There was no difference in the rejection rate of model eggs between the two populations of Barn Swallows,and clutch size was not a factor affecting egg recognition.Our results are consistent with the single rejection threshold model.This study provides strong experimental evidence that the color of model eggs can has an important effect on egg recognition in Barn Swallows,opening up new avenues to uncover the evolution of cuckoo egg mimicry and explore the cognitive mechanisms underlying the visual recognition of foreign eggs by hosts. 展开更多
关键词 Barn Swallow Egg color Hirundo rustica Multiple rejection threshold Single rejection threshold Visual recognition system
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Increased CO2 Levels during the First Half of Incubation at High Altitude Modifies Embryonic Development of Fertile Leghorn Breeder Eggs
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作者 Marco A. Juárez-Estrada Erik I. López-Ruiz +2 位作者 Sonia López-Cordova Guillermo Tellez-Isaias Omar F. Prado-Rebolledo 《Food and Nutrition Sciences》 CAS 2024年第7期524-547,共24页
The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditi... The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditions during the first ten days of incubation at high altitudes on Leghorn hens hatching eggs. Five hundred four hatching eggs were equally divided into three treatment groups and placed in twelve incubators (R = 4). The first group was subjected to standard ventilated conditions (V) during the setting phase. The ventilation inlet holes of the remaining incubators in the NV treatments were closed with either micropore (M) or polypropylene (P) tape, referred to as NVM and NVP groups, respectively. These two different airtight settings were intended to allow for a gradual rise in CO2 naturally generated by the embryos. Results indicate that carbon dioxide concentration gradually increased during the first half of incubation, reaching 1.42% in the NVM group and 1.20% in the NVP group, while the V condition group remained at 0.15%. From 10 days of incubation onwards, normal V conditions were restored in all incubators. The highest hatchability of fertile eggs (HFE) was shown by the NVP group (55.7%), followed by the V (52.6%) and NVM (38.6%) groups. The NVP group showed a greater yolk-free body mass (YFBM) from 10 days of incubation until the hatch basket transfer. NV conditions during the first 10 days of incubation at high altitude produced higher YFBM with gradually decreasing yolk sac mass. In comparison to the NVM and V conditions, the particular NVP condition showed a beneficial impact on the quality of hatched chicks. Sustaining NVP condition (1.2% of CO2) throughout the first half of incubation at high altitude generated the optimal environment in the incubator ensuring the best hatchability results. This study highlights how important it is for hatchery managers to recognize the influence of low O2 and high levels of CO2 on the development trajectories of Leghorn embryos during early incubation at high altitudes. 展开更多
关键词 Non-Ventilation HYPERCAPNIA Hypoxia Egg Mass Loss HATCHABILITY Embryonic Mortality Hatchling Chick Quality
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The amino acids differences in epitopes may promote the different allergenicity of ovomucoid derived from hen eggs and quail eggs
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作者 Mengzhen Hao Shuai Yang +1 位作者 Shiwen Han Huilian Che 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期861-870,共10页
Quail egg ovomucoid can inhibit activation of basophils and eosinophils,while hen egg ovomucoid has been shown to be a major allergen,named Gal d 1.At present,the differences in structure and function between two ovom... Quail egg ovomucoid can inhibit activation of basophils and eosinophils,while hen egg ovomucoid has been shown to be a major allergen,named Gal d 1.At present,the differences in structure and function between two ovomucoid are unclear.We found the homology of ovomucoid in quail eggs and hen eggs reached77%.Compared with hen egg ovomucoid,the distribution of secondary structure was different in AA52-53,AA57-58,AA66-68,AA71-72,AA131-133,AA139-140,AA157-159 and AA184-185.Among 9 epitopes of egg ovomucoid,there were different amino acids from quail egg ovomucoid in 8 epitopes.Recombination quail egg ovomucoid had trypsin inhibition activity and quail egg ovomucoid didn't specifically bind to serum of eggs allergic patients.Quail egg ovomucoid can significantly inhibit RBL-2 H3 cells degranulation and protect cells morphology to a certain extent,indicating quail egg ovomucoid can inhibit cells activation and have potential anti-allergic effects,which is related to trypsin inhibitory activity.The difference in sensitization compare to hen egg ovomucoid may be due to amino acids differences affecting protein structure by changing antigenic epitopes. 展开更多
关键词 Quail egg Hen egg OVOMUCOID Epitope DEGRANULATION
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Effects of Desmodium uncinatum Leaf Meal in the Diet on Lohmann Brown Hens’ Laying Performance and Eggs Quality
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作者 Hervé Mube Kuietche Cyrille D’Alex Tadondjou +4 位作者 Rubens Ngouana Tadjong Josiane Lobeng Mouaffo Fostso Jean Raphael Kana Alexis Teguia 《Open Journal of Animal Sciences》 CAS 2023年第1期166-178,共13页
A cheap, safe and available alternative protein source to soybean is a huge priority for the developing world. This study is aimed at evaluating the effects of Desmodium uncinatum leaf meal incorporation levels in the... A cheap, safe and available alternative protein source to soybean is a huge priority for the developing world. This study is aimed at evaluating the effects of Desmodium uncinatum leaf meal incorporation levels in the diet on Lohmann Brown hens’ laying performances. For this purpose, 60 Lohmann Brown hens aged 33 weeks with an average weight of 1.78 kg were randomly assigned to 3 treatment groups of 20 birds each with 4 replicates. The experimental treatments consisted of DULM <sub>0</sub>, DULM<sub>5</sub>, and DULM<sub>10</sub> containing 0, 5 and 10 kg of D. uncinatum leaf meal (DULM) per 100 kg of feed respectively. The results reveal that except for the weights of hens, laying performances were significantly affected (p < 0.05) by DULM in the diet. Daily feed intake was lower with 10% incorporation of DULM in the diet as compared to a diet with 5% DULM which recorded the highest value for this parameter. Moreover, the highest value for the egg weight, egg mass, yolk index, albumen index and egg production were recorded with diet DULM<sub>5</sub>. On the other hand, the diet with 10% of DULM (DULM<sub>10</sub>) recorded the highest relative shell weight, feed conversion ratio and egg price. Nevertheless, the mortality rate found in this study was 0% for all treatments confirming the good quality of DULM as protein feedstuff for layer. It was concluded that incorporation levels of D. uncinatum leaves at 5% in the diet improved the laying performances of Lohmann Brown hens. 展开更多
关键词 Desmodium uncinatum Laying Hens Egg Production Egg Quality
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Study on Effects of Different Factors to Eggs Hatching Rate of Cryptotympana atrata by Orthogonal Design
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作者 孙会忠 宋月芹 +1 位作者 董钧锋 纠敏 《Agricultural Science & Technology》 CAS 2011年第4期551-553,共3页
[Objective] The paper aimed to explore influence of different factors on eggs hatching of Cryptotympana atrata,and optimize technical parameters in practice.[Method] By using hatching rate as index,L16(44)orthogonal... [Objective] The paper aimed to explore influence of different factors on eggs hatching of Cryptotympana atrata,and optimize technical parameters in practice.[Method] By using hatching rate as index,L16(44)orthogonal design was employed to determine the effects of the four factors including temperature,salinity,photoperiod and pH.[Result] Photoperiod had obviously effects on hatchability of Cryptotympana atrata eggs.The optimal conditions for hatching were temperature 30 ℃,salinity 25%,photoperiod L12∶D12,and pH 6.[Conclusion]The research provided some scientific basis for indoor artificial incubation. 展开更多
关键词 Cryptotympana atrata eggs HATCHABILITY Orthogonal design
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Screening of Saprolegniasis Preventive Drugs for Golden Trout (Oncorhynchus mykiss) Fertilized Eggs During Hatching
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作者 李绍戊 刘红柏 《Agricultural Science & Technology》 CAS 2015年第9期1981-1984,1988,共5页
In order to screen the effective preventive drugs for saprolegniasis occurred during hatching of the fertilized eggs of golden trout, effects of two kinds of self-made Chinese herbal compounds(AB) and two kinds of c... In order to screen the effective preventive drugs for saprolegniasis occurred during hatching of the fertilized eggs of golden trout, effects of two kinds of self-made Chinese herbal compounds(AB) and two kinds of chemical bactericides(peroxyacetic acid andhydrogen peroxide, CD) with three disinfection concentrations were compared in this study. The fertilized eggs of golden trout were randomly divided into 13 groups, each group with two parallels of 1 000 eggs. Drugs at high,medium and low concentration were respectively used to immerse the fertilized eggs35 min for disinfection once a day. The numbers of live and dead eggs were recorded each day before disinfection and the numbers of survival eyed eggs were counted in each experimental group after finishing the whole test. The results indicated that all of four kinds of drugs used here had a certain effect on prevention and control of saprolegniasis during hatching of fertilized eggs of golden trout, and also showed a correlation between the concentrations and effects. After the selection of several drugs, we found that group B-medium, C-medium and D-high exhibited the most remarkable effects on control of saprolegniasis. However, careful consideration should be given to chemical drugs residues and their potential hazard to the eyed eggs. Therefore, Chinese herbal compound B was suggested to be used for prevention and control of saprolegniasis to achieve the healthy aquaculture. And the concentration and operation time of Chinese herbal compound B should be strictly controlled when used in disinfection of fertilized eggs. 展开更多
关键词 Golden trout(Oncorhynchus mykiss) Fertilized eggs SAPROLEGNIASIS Preventive drugs
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Analysis of the Production and Operation Status of Silkworm Eggs Producing Farms in China——Based on Questionnaire Survey to 136 Silkworm Eggs Producing Farms Nationwide
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作者 Li Jianqin Gu Guoda Feng Huaisong 《Animal Husbandry and Feed Science》 CAS 2014年第2期37-45,共9页
Through statistical analysis on questionnaire survey data from 136 silkworm eggs producing farms in China,it was concluded that most silkworm eggs producing farms had such problems as follows: old production facilitie... Through statistical analysis on questionnaire survey data from 136 silkworm eggs producing farms in China,it was concluded that most silkworm eggs producing farms had such problems as follows: old production facilities and poor production condition,heavy staff burden,weak scientific and technological support,small operation scale and heavy surplus production capacity; narrow silkworm eggs sale channels and stubborn regional segmentation,insufficient innovation and lack of technological support for diversified expansion. All these problems led to low labor productivity,low asset utilization rate and poor economic benefit in silkworm eggs producing farms in China. Except the provinces( regions) of Guangxi,Guangdong and Yunnan,the silkworm eggs producing farms in other provinces were generally at deficit condition. In the light of ownership,although silkworm eggs producing farms of different ownership systems were in the red,those of the private sector had the minimum deficit. Based on these findings,it is proposed to deepen system reformation of silkworm eggs producing farms,loosen control to price and circulation of silkworm eggs,implement large-scaled production and operation,speed up scientific and technological innovation,expand diversified development channels,and reinforce government support so as to increase production and operation benefits of silkworm eggs producing farms in China. 展开更多
关键词 Silkworm eggs producing farms Silkworm eggs PRODUCTION Operation BENEFIT OWNERSHIP
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A potential source of recruitment of Acartia pacifica nauplii: viable benthic resting eggs 被引量:11
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作者 WANGGulzhong JIANGXiaodong LIShaojing WULisheng WUDingxun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第2期151-158,共8页
Many estuarine and coastal planktonic copepods depend on the hatching of benthic resting eggs for recruitment of nauplii to the water column population. The distribution and abundance of viable resting eggs of Acartia... Many estuarine and coastal planktonic copepods depend on the hatching of benthic resting eggs for recruitment of nauplii to the water column population. The distribution and abundance of viable resting eggs of Acartia pacifica in the Xiamen Bay were determined by the presence of nauplii in the laboratory. The number of viable eggs var/ed temporally and spatially. The maximum number (9.2×10^4m^-2) of viable eggs was in summer. In spring the average abundance of viable eggs was 5.6×10^4 m^-2. The abundances of viable eggs in fall and winter were similar, respectively 2.7×10^4 and 3.3×10^4m^-2, which were the lowest in the year. The numbers of viable eggs inside the stations of the Xiamen Bay were higher than those outside the stations. The viable eggs were found at all depths (0-10 cm),although not in every station. The maximum number did not necessarily occur in the uppermost centimeter of the sediments but often occurred several centimeters below the water-sediment interface. The accumulation of viable eggs in the seabed of a subtropical bay constitutes a potential source of recruitment of nauplii into the pelagic population. 展开更多
关键词 RECRUITMENT resting eggs Acartia pacifica
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Developmental Threshold Temperature and Effective Accumulative Tem- perature of Pupae and Eggs of Holcocerus hippophaecolus 被引量:8
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作者 ZongShixiang LuoYouqing WangTao XuZhichun LuChangkuan 《Forestry Studies in China》 CAS 2004年第4期34-38,共5页
In order to understand the occurrence and the developmental regularity of seabuckthorn carpenterworm (Holcocerus hippophaecolus) and predict its population density, the developmental threshold temperature (C) and effe... In order to understand the occurrence and the developmental regularity of seabuckthorn carpenterworm (Holcocerus hippophaecolus) and predict its population density, the developmental threshold temperature (C) and effective accumulative tem- perature (K) of the carpenterworm pupae and eggs were analyzed under the conditions of constant and variable temperatures. The results show that the values of C and K of the carpenterworm pupae are (12.1 ± 0.2) °C and (295.2 ± 4.1) day-degrees at constant temperatures, and (15.5 ± 0.4) °C and (202.4 ± 13.1) day-degrees at variable temperatures. However, the values of C and K of the eggs at variable temperatures are (16.7 ± 0.8) °C and (101.5 ± 12.6) day-degrees. The differences of developmental threshold and effective accumulative temperature under the conditions of constant and variable temperatures of the carpenterworm pupae accord with the developmental regularity of most insects in nature. By comparing five different constant temperatures, the conclusion is that the optimum developmental temperature of the pupae is 21 °C when both the pupation of the mature larvae and the eclosion of the pupae are very accordant. Moreover, the percentage of eclosion is over 90%. The average developmental durations of the carpenter- worm pupae and eggs are 31 and 16 d at variable temperatures. 展开更多
关键词 Holcocerus hippophaecolus PUPAE eggs developmental threshold temperature effective accumulative tempera- ture
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Effects of Predation by Invasive Western Mosquitofish(Gambusia affinis) on Survival of Eggs,Embryos and Tadpoles of Pelophylax nigromaculatus and Duttaphrynus melanostictus in South China 被引量:3
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作者 Xiaoli FAN Zhihua LIN +2 位作者 Xiang LI Li WEI Guohua DING 《Asian Herpetological Research》 SCIE CSCD 2016年第1期46-52,共7页
Alien species are one of the most serious threats to the decline and extinction of native amphibian populations. In this study, we examined the predation of invasive Western Mosquitofish Gambusia affinis on the eggs, ... Alien species are one of the most serious threats to the decline and extinction of native amphibian populations. In this study, we examined the predation of invasive Western Mosquitofish Gambusia affinis on the eggs, embryos, and tadpoles of Duttaphrynus melanostictus and Pelophylax nigromaculatus in south China. Our results suggested that the survival of eggs and embryos remaining in the egg capsules of P. nigromaculatus and D. melanostictus was significantly higher than those removed from the egg capsule at 12-h intervals within 72 h in the presence of G. affinis. The survival of P. nigromaculatus eggs and embryos without egg capsules was significantly lower than those of D. melanostictus without egg capsules. The survival of P. nigromaculatus eggs and embryos with egg capsules was significantly higher than those of D. melanostictus with egg capsules from 24 h to 72 h except for 12 h. The survival of D. melanostictus tadpoles was significantly higher than that of P. nigromaculatus tadpoles in the presence of G. affinis. The survival of Gosner stage 26 tadpoles of P. nigromaculatus was significantly higher than that of Gosner stage 30 tadpoles from 12 h to 60 h, but there were no significant differences at 72 h. In contrast, the survival of Gosner stage 26 tadpoles of D. melanostictus was significantly lower than that of Gosner stage 30 tadpoles within 72 h, recording every 12 h. The increasing temperature caused a significant increase in predation by G. affinis on P. nigromaculatus eggs and embryos. The outer jelly capsule surrounding anurans eggs might serve as a mechanical defense against predation by G. affinis due to its large diameter, relatively stationary state and unpalatability. The differences in the vulnerability of P. nigromaculatus and D. melanostictus embryos and tadpoles to G. affinis probably due to differences in the unpalatability, black skin and activity. Based on the magnitude of predation by G. affinis on the eggs, embryos and tadpoles of these two species and the combined impact of temperature, we might speculate that invasive G. affinis and global warming would have more detrimental impacts on population viability of P. nigromaculatus than D. melanostictus in China. 展开更多
关键词 amphibian anura TADPOLES eggs embryos predation risk
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Prediction Model of Weekly Retail Price for Eggs Based on Chaotic Neural Network 被引量:3
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作者 LI Zhe-min CUI Li-guo +4 位作者 XU Shi-wei WENG Ling-yun DONG Xiao-xia LI Gan-qiong YU Hai-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2292-2299,共8页
This paper establishes a short-term prediction model of weekly retail prices for eggs based on chaotic neural network with the weekly retail prices of eggs from January 2008 to December 2012 in China.In the process of... This paper establishes a short-term prediction model of weekly retail prices for eggs based on chaotic neural network with the weekly retail prices of eggs from January 2008 to December 2012 in China.In the process of determining the structure of the chaotic neural network,the number of input layer nodes of the network is calculated by reconstructing phase space and computing its saturated embedding dimension,and then the number of hidden layer nodes is estimated by trial and error.Finally,this model is applied to predict the retail prices of eggs and compared with ARIMA.The result shows that the chaotic neural network has better nonlinear fitting ability and higher precision in the prediction of weekly retail price of eggs.The empirical result also shows that the chaotic neural network can be widely used in the field of short-term prediction of agricultural prices. 展开更多
关键词 chaos theory chaotic neural network neural network technology short-term prediction weekly retail price of eggs
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Reduction of hydrocarbon contamination on viability of Acartia pacifica benthic resting eggs 被引量:3
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作者 姜晓东 王桂忠 林琼武 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第1期91-96,共6页
The potential effect of hydrocarbon contamination on the hatching success of benthic resting eggs of Acartia pacifica in Xiamen Bay was investigated experimentally. The number of nauplii emerging from the sediment sam... The potential effect of hydrocarbon contamination on the hatching success of benthic resting eggs of Acartia pacifica in Xiamen Bay was investigated experimentally. The number of nauplii emerging from the sediment samples decreased with increasing Fuel Oil #0 concentration. The estimated rate of mortality increased markedly with the increase of Fuel Oil #0 concentration. Successive fuel Oil #0 concentrations from 50 mg/kg to 5000 mg/kg reduced the number of hatched nauplii by 3.8% -100%. The mortality of A. pacifica resting eggs due to Fuel Oil #0 contamination did not significantly increase as time progressed at each concentration level. The LC50 values of resting eggs, changing from 237.12 to 279.59 mg/kg, remained at an almost stable level in two months. The number of A. pacifica nauplii that hatched from the sediment at 10℃ was higher than those from the sediment at 30℃, which indicates that the toxicity of Fuel Oil #0 on A. pacifica resting eggs increases with increasing temperature. 展开更多
关键词 hydrocarbon contamination resting eggs Acartia pacifica
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An Updated Review on Chicken Eggs: Production, Consumption, Management Aspects and Nutritional Benefits to Human Health 被引量:3
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作者 Khalid Zaheer 《Food and Nutrition Sciences》 2015年第13期1208-1220,共13页
Ancestors of the modern chicken were domesticated from members of the Gallus genus probably 7 to 8 thousand years ago in southeastern Asia. Subsequently, they spread globally for meat and egg production. In the chicke... Ancestors of the modern chicken were domesticated from members of the Gallus genus probably 7 to 8 thousand years ago in southeastern Asia. Subsequently, they spread globally for meat and egg production. In the chicken egg, there is a balance of numerous, high-quality nutrients, many of which are highly bioavailable. The egg confers a multitude of health benefits to consumers emphasizing its classification as a functional food. Current global per capita egg consumption estimates approach 9 kg annually but vary greatly on a regional basis. This review deals with global production, consumption, and management aspects such as hygiene, feeding, and housing. Management aspects play key roles in the composition, quality, food safety, and visual (consumer) appeal of the egg. Also the manipulation of egg nutrients and value for human health is discussed. 展开更多
关键词 CHICKEN eggs PRODUCTION CONSUMPTION Nutrient Manipulation Egg Quality Bioavailability Health BENEFITS
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Egg recognition in Cinereous Tits(Parus cinereus):eggshell spots matter 被引量:2
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作者 Jianping Liu Canchao Yang +2 位作者 Jiangping Yu Haitao Wang Wei Liang 《Avian Research》 CSCD 2019年第4期447-452,共6页
Background:Brood parasitic birds such as cuckoos(Cuculus spp.)can reduce their host’s reproductive success.Such selection pressure on the hosts has driven the evolution of defense behaviors such as egg rejection agai... Background:Brood parasitic birds such as cuckoos(Cuculus spp.)can reduce their host’s reproductive success.Such selection pressure on the hosts has driven the evolution of defense behaviors such as egg rejection against cuckoo parasitism.Studies have shown that Cinereous Tits(Parus cinereus)in China have a good ability for recognizing foreign eggs.However,it is unclear whether egg spots play a role in egg recognition.The aims of our study were to investigate the egg recognition ability of two Cinereous Tit populations in China and to explore the role of spots in egg recognition.Methods:To test the effect of eggshell spots on egg recognition,pure white eggs of the White-rumped Munia(Lonchura striata)and eggs of White-rumped Munia painted with red brown spots were used to simulate experimental parasitism.Results:Egg experiments showed that Cinereous Tits rejected 51.5%of pure white eggs of the White-rumped Munia,but only 14.3%of spotted eggs of the White-rumped Munia.There was a significant difference in egg recognition and rejection rate between the two egg types.Conclusions:We conclude that eggshell spots on Cinereous Tit eggs had a signaling function and may be essential to tits for recognizing and rejecting parasitic eggs. 展开更多
关键词 Brood parasitism Egg recognition Egg rejection eggshell spots Parus cinereus
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Effect of Intertidal Elevation at Tsuyazaki Cove,Fukuoka,Japan on Survival Rate of Horseshoe Crab Tachypleus tridentatus Eggs 被引量:1
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作者 ITAYA Shinji SHUUNO Mari +2 位作者 ONIKURA Norio TAI Akira YANO Shinichiro 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第3期601-610,共10页
Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg s... Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg survival rates per day were highest in the mid intertidal zone(45.1%±25.4%)and the lowest in the low intertidal zone(13.3%±27.6%).Differences in the elevation,air exposure time,and water content of the spawning ground were significant factors determining the egg survival rates.Excessive or insufficient air exposure time resulted in inadequate water content at higher and lower intertidal zones and could reduce egg survival.On the other hand,moderate saturation and dehydration were repeated with each tidal movement in the mid intertidal zone.This dynamic is considered as one of the crucial factors for the survival of eggs and is considered optimal for spawning.Therefore,the protection of the mid intertidal zone is imperative for maximizing the egg survival rate in Tsuyazaki Cove where almost all suitable nesting sites have disappeared due to coastal development.By protecting these optimal sites for spawning and recovering other optimal sites on suitable beaches,a positive contribution can be made to future management and conservation.The study also suggests that translocating eggs from marginal to optimal spawning sites might be a recovery strategy for this globally endangered species. 展开更多
关键词 air exposure time globally endangered species intertidal elevation intertidal zone optimal spawning site Tachypleus tridentatus translocated horseshoe crab eggs Tsuyazaki Cove
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Unhatched and Hatched Eggshells of the Chinese Cobra Naja atra 被引量:1
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作者 Zheng WANG Longhui LIN Xiang JI 《Asian Herpetological Research》 SCIE 2014年第4期276-280,共5页
Changes in structure and composition of the eggshell resulting from embryonic mobilization of minerals from the eggshell are found in all oviparous reptiles studied thus far. In this study, we measured samples of unha... Changes in structure and composition of the eggshell resulting from embryonic mobilization of minerals from the eggshell are found in all oviparous reptiles studied thus far. In this study, we measured samples of unhatched and hatched eggshells of the Chinese cobra Naja atra to determine the percentage of ash and the phase composition of calcium carbonate. The mean percentage of ash was significantly higher in unhatched eggshells (24.6%) than in hatched eggshells (22.3%). The dominant phase in unhatched eggshells was the calcite form of calcium carbonate. In addition to the peaks of calcite, a few small peaks were found to be caused by the aragonite and vaterite phases of calcium carbonate, implying that there are small amounts of aragonite and vaterite in the eggshell. The concentration of the various phases calculated from the intensity of the X-ray diffraction spectra allowed the estimation that percentages of calcite, aragonite and vaterite were about 92%, 4% and 4%, respectively. Hatched eggshells produced similar spectral characteristics as unhatched eggshells, with one exception. The dominant phase composition in the hatched eggshell was also calcite, but the amount of the aragonite phase had a marked increase. Our study adds evidence that embryonic mobilization of minerals from the eggshell may result in changes in structure of the eggshell. 展开更多
关键词 ELAPIDAE Naja atra eggshell structure egg incubation X-ray diffraction spectra MINERALS
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Detection of Persistent Organochlorine Pollutants in Eggs of Antarctic Seabirds Based on Gas Chromatography and Their Ecological Environment Significance 被引量:1
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作者 Ye Maosen Zhang Rongbao +4 位作者 Chen Lihong Lin Bo Zheng Fangqin Lu Bing Ye Xinrong 《Meteorological and Environmental Research》 CAS 2016年第1期48-51,54,共5页
By using internal standard method based on gas chromatography-electron capture detector (GC-ECD), the contents of persistent or- ganochlorine pollutants polychorinated biphenyls (PCBs) and organochlorine pesticid... By using internal standard method based on gas chromatography-electron capture detector (GC-ECD), the contents of persistent or- ganochlorine pollutants polychorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in eggs of seabirds ( Catharacta Ionnbergi, Cathar- acta maccormicki, Pygoscelis papua and Macronectes giganteus) breeding on King George Island, Antarctica were detected, and their ecological environment significance was discussed. The results showed that the recovery of various compounds ranged from 68.6% to 90.8% ; relative stand- ard deviation (RSD) was 3.6%, and the lowest detection limits of PCBs and OCPs were 0.8 - 16 and 2 - 12 pg respectively, which could meet the demands for the residue analysis of trace persistent organochlorine pollutants in the eggs of Antarctic seabirds. The contents of PCBs, DDTs, HCB and HCHs in the eggs of Antarctic seabirds were 0.5 -515.5, 2.0 -304.4,0.5 -70.5, and 0.5 -2.0 ng/g respectively. In addition, the accumula- tion of PCBs and OCPs in the skuas was enhanced gradually through the food chain. The maximums of persistent organochlorine pollutants ap- peared in the eggs of C. Ionnbergi, followed by the eggs of C. maccomicki. The detection of OCPs and PCBs in the eggs of Antarctic seabirds was not interfered by other compounds containing chlorine, showing that the extraction, purification and detection method was suitable for the analysis of OCPs and PCBs in the eggs of Antarctic seabirds and has high sensitivity and reliability. 展开更多
关键词 Gas chromatography eggs of Antarctic penguins and skuas Persistent organochlorine pollutants China
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Developmental stages and quality traits of giant African land snails [<i>Archachatina marginata</i>(swainson)] eggs 被引量:1
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作者 B. Okon L. A. Ibom +1 位作者 I. E. Ebenso A. E. Bassey 《Natural Science》 2013年第10期1121-1126,共6页
Sixty sexually mature purebred black-skinned Archachatina marginata snails with weight ranging from 120.50 g to 135.70 g were used to generate eggs in this study. The eggs collected were incubated in a chamber filled ... Sixty sexually mature purebred black-skinned Archachatina marginata snails with weight ranging from 120.50 g to 135.70 g were used to generate eggs in this study. The eggs collected were incubated in a chamber filled with loamy soil for appropriate observation and assessment (cracking at four days intervals to check snailet’s development). Results obtained from the study showed that at laying snail egg weights ranged from 1.54 - 2.45 g (mean of 2.00 g). The egg lengths and widths ranged from 13.50 - 16.90 mm (mean of 15.20 mm) and 10.00 - 12.70 mm (mean of 11.40 mm) respectively. The results also revealed that at laying (day one) the egg content was translucent or clear (blank) when observed with light from a powered microscope. Observation of eggs on day four showed the formation of embryo with a semi-transparent cup attached to a long string body. On day 12, some specific organs of the snailet had developed, and there was a reduction in the liquid content. On day 28, the snailet was fully formed, but the shell still contained very small volume of liquid. The snailet hatched on day 29. 展开更多
关键词 Development Quality TRAITS eggs SNAIL STAGES
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Escamoles Ant Eggs Liometopumapiculatumm Source of Metal Ions for Human Health 被引量:1
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作者 Virginia Melo Concepcion Calvo +2 位作者 Tomas Quirino Susana Macin Ileana Muniz 《Journal of Chemistry and Chemical Engineering》 2013年第6期556-559,共4页
The earth crust is believed to be made of a mass of minerals and is matched by their importance in human life. The human body, depend like other leaving organisms, on several minerals as essential constituents of its ... The earth crust is believed to be made of a mass of minerals and is matched by their importance in human life. The human body, depend like other leaving organisms, on several minerals as essential constituents of its existence. Metal ions in foodstuff are in different chemical forms, as inorganic salts or organic molecules or complexes with other compounds such as proteins, amino acids, enzymes and some vitamins, among others, that play an important role in human health. Entomophagy, insect consumption by several ethnic groups in Mexico as cultural tradition since prehispanic era represent an option for population to obtain the minerals needed by the body to keep a good health. Escamoles ant eggs of the Liometopumapiculatum M genus, much appreciated either at rural communities as well as in urban cities, contain minerals with a favorable effect in human health. The aim of this study was to investigate the mineral composition of Escamoles and the benefits which can provide to the human body. Sampling was at an arid region of the Hidalgo state on April 2012. Minerals in dry basis, determined by atomic absorption spectrophotometry, with the exception of phosphorus content, obtained from a triple acid digested extract and determined colorimetrically. Data of mineral analysis in dry basis of Escamoles were: total minerals 5.92%; Na 0.079%; K 0.075%; Ca 0.097%; P 0.701%; Fe 0.021%; Zn 0.035% Cu 0.009%; Mg 0.998%; Mn 0.002%. Minerals quantify are not equal to total ash contained because not all of them were assess determined. Elements concentration depends not only on the total mineral composition of foodstuff the inorganic or organic form or interaction among metal ions, but also on their availability and avail of them. Minerals in Escamoles ant eggs have a considerable influence in the condition of human health. 展开更多
关键词 Escamoles ant eggs metal ions human health.
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Effects of Storage Time on External and Internal Characteristics of Lutein Enriched Eggs 被引量:1
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作者 Kanda Lokaewmanee Peeyanut Meesrri 《Journal of Agricultural Science and Technology(B)》 2015年第9期643-646,共4页
In this paper, the effects of storage time on the external and internal characteristics of lutein enriched eggs were studied. A total of 330 lutein eggs were stored at room temperature (30℃) for periods of 0, 3, 5,... In this paper, the effects of storage time on the external and internal characteristics of lutein enriched eggs were studied. A total of 330 lutein eggs were stored at room temperature (30℃) for periods of 0, 3, 5, 7, 9, 11, 13, 15, 17, 19 and 21 d, respectively. At the end of each storage period, 30 lutein eggs were evaluated for egg quality. Storage time from 0 d to 21 d did not affect the eggshell thickness, shell ratio and yolk color (P 〉 0.05). The effect of days in storage was statistically significant on the albumen ratio and Haugh unit (P 〈 0.05), both of which decreased with increasing days of storage. Conversely, egg water loss and the yolk ratio increased with increasing days of storage (P 〈 0.05). At the end of storage, the lutein value in the eggs was close to the value at the beginning of storage. The results indicated that storage time did not produce an adverse effect on the eggshell thickness, shell ratio, yolk color and concentration of lutein in lutein enriched eggs. 展开更多
关键词 Storage time CHARACTERISTICS lutein enriched eggs.
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