Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimizati...Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimization strategy during spring migration, resulting in shorter duration spring migration compared to that in autumn.Methods:Using GPS/GSM transmitters,we tracked the full migrations of 11 Greater White-fronted Geese (Anser albifrons) between southeast China and the Russian Arctic,to reveal the migration timing and routes of the East Asian population, and compare the difference in duration between spring and autumn migration of this population.Results:We found that migration in spring (79 ± 12 days) took more than twice as long to cover the same distance as in autumn (35 ±7 days).This difference in migration duration was mainly determined by significantly more time spent in spring (59±16 days) than in autumn (23± 6days) at significantly more stopover sites. Conclusions:We suggest that these geese, thought to be partial capital breeders, spent almost three quarters of total migration time at spring stopover sites to acquire energy stores for ultimate investment in reproduction, although we cannot reject the hypothesis that timing of the spring thaw also contributed to stopover duration.In autumn,they acquired necessary energy stores on the breeding grounds sufficient to reach Northeast China staging areas almost without stop, which reduced stopover times in autumn and resulted in the faster autumn migration than spring.展开更多
[Objective] To explore the law of intestinal development of Wanxi white geese at 0 -9 weeks old. [Method] A total of 120 Wanxi white geese at 1 day old were selected, and their law of development of intestinal weight ...[Objective] To explore the law of intestinal development of Wanxi white geese at 0 -9 weeks old. [Method] A total of 120 Wanxi white geese at 1 day old were selected, and their law of development of intestinal weight and length was studied by feeding test and slaughter test. [ Re- sult] The growth of Wanxi white geese was slow in the early age, rapid at the age of 2 -5 wk, peaked at about 5 weeks old, and then slowed. The daily weight gain was around 25 g/d at the age of 7 -9 wk. Intestinal growth also peaked at 5 weeks old and almost developed fully at 7 weeks old. Thus, intestinal growth had a similar law with body weight. With the development, the ratios of the length of each intestinal segment to that of total intestinal tract did not vary largely. [ Conclusion] The study provides a theoretical basis for the production and development of germplasm resources of Wanxi white geese.展开更多
[Objective] The study aimed to clone interleukin-2(IL-2) gene from Sichuan white goose. [Method] Based on the IL-2 gene of duck accessed in GenBank, a pair of primers was designed for cloning IL-2 gene from total RNA ...[Objective] The study aimed to clone interleukin-2(IL-2) gene from Sichuan white goose. [Method] Based on the IL-2 gene of duck accessed in GenBank, a pair of primers was designed for cloning IL-2 gene from total RNA of peripheral blood lymphocytes of Sichuan white goose stimulated by ConA via RT-PCR technology. The yielded fragment was sequenced for bioinformatics analysis. [Result] The full length of IL-2 gene of Sichuan white goose is 468 bp that contains a 441 bp open reading frame(ORF), encoding 146 amino acid residues. Bioinformatics analysis shows that the amino acid sequence of IL-2 gene of Sichuan white goose contains four phosphorylation sites, a glycosylation site and a signal peptide with 21 amino acid residues. Homologies of IL-2 nucleotide sequence and amino acid sequence between Sichuan white goose and duck, chicken, turkey are 92.7%, 77.5%, 78.2% and 85.8%, 65.5%, 64.1%, respectively. By contrast IL-2 nucleotide sequence and amino acid sequence between Sichuan white goose and mammalian and rodents such as human, monkey, rat, bovine, horse, pig, cat, mouse, rabbit and deer, are all less than 45% and 28%, respectively. [Conclusion] The IL-2 gene of Sichuan white goose has closer genetic relationship with those of chicken and duck.展开更多
基金supported by the National Key Research and Development Programme of China(Grant No.2016YFC0500406)the Chinese Academy of Sciences Key Strategic Programme,Water Ecological Security Assessment,the Major Research Strategy for Middle and Lower Yangtze River(Grant No.ZDRWZS-2017-3-3)the National Natural Science Foundation of China(Grant Nos.31661143027,31670424,31700330)
文摘Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimization strategy during spring migration, resulting in shorter duration spring migration compared to that in autumn.Methods:Using GPS/GSM transmitters,we tracked the full migrations of 11 Greater White-fronted Geese (Anser albifrons) between southeast China and the Russian Arctic,to reveal the migration timing and routes of the East Asian population, and compare the difference in duration between spring and autumn migration of this population.Results:We found that migration in spring (79 ± 12 days) took more than twice as long to cover the same distance as in autumn (35 ±7 days).This difference in migration duration was mainly determined by significantly more time spent in spring (59±16 days) than in autumn (23± 6days) at significantly more stopover sites. Conclusions:We suggest that these geese, thought to be partial capital breeders, spent almost three quarters of total migration time at spring stopover sites to acquire energy stores for ultimate investment in reproduction, although we cannot reject the hypothesis that timing of the spring thaw also contributed to stopover duration.In autumn,they acquired necessary energy stores on the breeding grounds sufficient to reach Northeast China staging areas almost without stop, which reduced stopover times in autumn and resulted in the faster autumn migration than spring.
基金funded by the Natural Science Foundation of Education Department of Henan Province ( 2010B230013)Youth Research Fund of Zhoukou Normal University( zknuqn201030A)
文摘[Objective] To explore the law of intestinal development of Wanxi white geese at 0 -9 weeks old. [Method] A total of 120 Wanxi white geese at 1 day old were selected, and their law of development of intestinal weight and length was studied by feeding test and slaughter test. [ Re- sult] The growth of Wanxi white geese was slow in the early age, rapid at the age of 2 -5 wk, peaked at about 5 weeks old, and then slowed. The daily weight gain was around 25 g/d at the age of 7 -9 wk. Intestinal growth also peaked at 5 weeks old and almost developed fully at 7 weeks old. Thus, intestinal growth had a similar law with body weight. With the development, the ratios of the length of each intestinal segment to that of total intestinal tract did not vary largely. [ Conclusion] The study provides a theoretical basis for the production and development of germplasm resources of Wanxi white geese.
文摘[Objective] The study aimed to clone interleukin-2(IL-2) gene from Sichuan white goose. [Method] Based on the IL-2 gene of duck accessed in GenBank, a pair of primers was designed for cloning IL-2 gene from total RNA of peripheral blood lymphocytes of Sichuan white goose stimulated by ConA via RT-PCR technology. The yielded fragment was sequenced for bioinformatics analysis. [Result] The full length of IL-2 gene of Sichuan white goose is 468 bp that contains a 441 bp open reading frame(ORF), encoding 146 amino acid residues. Bioinformatics analysis shows that the amino acid sequence of IL-2 gene of Sichuan white goose contains four phosphorylation sites, a glycosylation site and a signal peptide with 21 amino acid residues. Homologies of IL-2 nucleotide sequence and amino acid sequence between Sichuan white goose and duck, chicken, turkey are 92.7%, 77.5%, 78.2% and 85.8%, 65.5%, 64.1%, respectively. By contrast IL-2 nucleotide sequence and amino acid sequence between Sichuan white goose and mammalian and rodents such as human, monkey, rat, bovine, horse, pig, cat, mouse, rabbit and deer, are all less than 45% and 28%, respectively. [Conclusion] The IL-2 gene of Sichuan white goose has closer genetic relationship with those of chicken and duck.
