Aim： To assess whether exogenous estradiol has any effect on migration of primordial germ cells （PGCs） in the chick. Methods： Fertilized eggs were treated with 17beta-estradiol （E2） （80 lag/egg） at stage X （d...Aim： To assess whether exogenous estradiol has any effect on migration of primordial germ cells （PGCs） in the chick. Methods： Fertilized eggs were treated with 17beta-estradiol （E2） （80 lag/egg） at stage X （day 0 of incubation）, stages 8-10 （incubation 30 h） and 13-15 （incubation 55 h）. Controls received vehicle （emulsion） only. Changes in PGC number were measured on different days according to developmental stages. Results： In male right gonads, but not in female left gonads, at stages 28-30 （incubation 132 h） significant decreases in the mean number of PGCs aggregating were observed compared with the controls （P 〈 0.05） while the total PGC number in the right and left gonads at each stage did not change （P 〉 0.05）. Conclusion： The present study provides evidence that E2 has significant effects on the localization of PGCs in male right, but not female left, gonads of chicken embryos at stages 28-30, compared with controls. （Asian J Andro12008 Mar; 10： 243-248）展开更多
Numerous researchers and institutions have been developing in ovo sexing technologies to improve animal welfare by identifying male embryos in an early embryonic stage and disposing of them before pain perception.This...Numerous researchers and institutions have been developing in ovo sexing technologies to improve animal welfare by identifying male embryos in an early embryonic stage and disposing of them before pain perception.This review gives a complete overview of the technological approaches reported in papers and patents by performing a thorough search using Web of Science and Patstat/Espacenet databases for papers and patents,respectively.Based on a total of 49 papers and 115 patent families reported until May 2023 worldwide,11 technology categories were defined:6 non-optical and 5 optical techniques.Every category was described for its characteristics while assessing its potential for application.Next,the dynamics of the publications of in ovo sexing techniques in both paper and patent fields were described through growth curves,and the interest or actual status was visualized using the number of paper citations and the actual legal status of the patents.When comparing the reported technologies in papers to those in patents,scientific gaps were observed,as some of the patented technologies were not reported in the scientific literature,e.g.,ion mobility and mass spectrometry approaches.Generally,more diverse approaches in all categories were found in patents,although they do require more scientific evidence through papers or industrial adoption to prove their robustness.Moreover,although there is a recent trend for non-invasive techniques,invasive methods like analyzing DNA through PCR or hormones through immunosensing are still being reported(and might continue to be)in papers and patents.It was also observed that none of the technologies complies with all the industry requirements,although 5 companies already entered the market.On the one hand,more research and harmony between consumers,industry,and governments is necessary.On the other hand,close monitoring of the market performance of the currently available techniques will offer valuable insights into the potential and expectations of in ovo sexing techniques in the poultry industry.展开更多
基金Acknowledgment This work was supported by the National Natural Science Foundation of China （No. 30270648 and No. 30500270）, Zhejiang Province Scientific and Technological Project （No. 2005C22052） and Zhejiang Province Science Foundation （No. Y304194）. We thank Dr Ji- Min Zhang of the University of California for linguistic revision of the manuscript.
文摘Aim： To assess whether exogenous estradiol has any effect on migration of primordial germ cells （PGCs） in the chick. Methods： Fertilized eggs were treated with 17beta-estradiol （E2） （80 lag/egg） at stage X （day 0 of incubation）, stages 8-10 （incubation 30 h） and 13-15 （incubation 55 h）. Controls received vehicle （emulsion） only. Changes in PGC number were measured on different days according to developmental stages. Results： In male right gonads, but not in female left gonads, at stages 28-30 （incubation 132 h） significant decreases in the mean number of PGCs aggregating were observed compared with the controls （P 〈 0.05） while the total PGC number in the right and left gonads at each stage did not change （P 〉 0.05）. Conclusion： The present study provides evidence that E2 has significant effects on the localization of PGCs in male right, but not female left, gonads of chicken embryos at stages 28-30, compared with controls. （Asian J Andro12008 Mar; 10： 243-248）
基金the Foundation for Food and Agricultural Research[EggTech-0000000028]the Research Foundation-Flanders[SB project 1SC7219N and SB project 1S54823N].
文摘Numerous researchers and institutions have been developing in ovo sexing technologies to improve animal welfare by identifying male embryos in an early embryonic stage and disposing of them before pain perception.This review gives a complete overview of the technological approaches reported in papers and patents by performing a thorough search using Web of Science and Patstat/Espacenet databases for papers and patents,respectively.Based on a total of 49 papers and 115 patent families reported until May 2023 worldwide,11 technology categories were defined:6 non-optical and 5 optical techniques.Every category was described for its characteristics while assessing its potential for application.Next,the dynamics of the publications of in ovo sexing techniques in both paper and patent fields were described through growth curves,and the interest or actual status was visualized using the number of paper citations and the actual legal status of the patents.When comparing the reported technologies in papers to those in patents,scientific gaps were observed,as some of the patented technologies were not reported in the scientific literature,e.g.,ion mobility and mass spectrometry approaches.Generally,more diverse approaches in all categories were found in patents,although they do require more scientific evidence through papers or industrial adoption to prove their robustness.Moreover,although there is a recent trend for non-invasive techniques,invasive methods like analyzing DNA through PCR or hormones through immunosensing are still being reported(and might continue to be)in papers and patents.It was also observed that none of the technologies complies with all the industry requirements,although 5 companies already entered the market.On the one hand,more research and harmony between consumers,industry,and governments is necessary.On the other hand,close monitoring of the market performance of the currently available techniques will offer valuable insights into the potential and expectations of in ovo sexing techniques in the poultry industry.
