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1.
Autumn migration of Quail was studied on the northern coast of Sinai in 1972 and 1973. Arab Quail nets were used to catch totals of 4863 and 1823 in the two years, respectively. Of 1761 Quail ringed in 1973, 0–4% have been recovered from the extensive area predicted by earlier ringing results. Quail started to enter nets 10 min after first light, and continued to do so until 0800–0900 h, local time. The quantity netted per day varied greatly, producing waves of migration which were inversely correlated with the barometric pressure over Europe prior to the arrival of each wave. Each of the arriving waves was apparently a discrete (group of) populations) from one area. The very close similarities in the arrival dates of each wave for both the 1972 and 1973 passages has been interpreted as showing that the timing of autumn migration in Quail is mainly dependent on exteroreceptive time–setters and/or biological clocks. Sex and age ratios of each day's catch varied greatly and were related to the rise and fall in numbers of Quail arriving each day. The approximate sex and age ratios for all Quail crossing the coast after dawn during the 1973 passage was 58% male, 75% young, and 7–2 young per adult female. The 26 Quail analysed for fat and water content were definitely not suffering from dehydration, but many of them would not have been able to reach their wintering grounds without additional food. The ‘average’ Quail had 75% of the fat reserves required, while less than 20% of the Quail had the required amount. The daily temporal pattern of netting suggests that a proportion of the Quail cross the coast before dawn and alight at dawn well dispersed within the Sinai desert. This, together with the observed inverse correlation between the amount of fat at arrival and the time of netting, suggest that it is the Quail in poorer physiological condition that arrive later in the day, and that these may stand smaller chances of completing their autumn migration even if not netted by man. More than three times the number of Quail were caught per metre net in 1972 than 1973 (2–43 Quail/metre net/season and 0–73 Quail/metre net/season, respectively. This decline cannot be attributed to hunting. Rough quantitative data during the years 1900–1959 shows that the abundance of Quail in any year was not dependent on abundance in the preceding year. On the other hand, fluctuations in Quail abundance were associated with long–term climatic changes, i.e., netting success in Egypt was negatively associated with rainfall in the Sahel, and shooting in Luxembourg was positively correlated with temperatures in Germany. 相似文献
2.
蜡嘴,锡嘴雀和法国鹌鹑耳蜗—中脑听觉中枢的比较观察 总被引:3,自引:1,他引:2
用辣根过氧化物酶HRP顺行标记方法表明蜡嘴(Eophona migratoria)、锡嘴(Coccothra-ustes coccothraustes)和鹌鹑(France Coturnix coturnix)脑干内听觉中枢的初级神经元位于耳蜗核(nCO,Cochlear unclei)内。较高级神经元位于中脑背外侧核(MLD,Nucleus mesen-cephalicus lateralis,pars dorsalis)。脑干内听觉传入通路始于nCO,经外侧丘系(LL,Lemni-scus lateralis)可直接投射于MLD。鸣禽鸟蜡嘴、锡嘴是对侧投射,同侧仅有个别纤维被标记,非鸣禽鹌鹑仅是对侧性投射。 相似文献
3.
D. D. B. Summers 《Ibis》1972,114(1):79-88
Japanese Quail were kept in small cages under controlled conditions of temperature and light, and their pterylography and moult are described. There are 10 primaries, 14 secondaries and corresponding numbers of greater upper and lower wing coverts. The alula has four feathers and the tail from five to six pairs of feathers. There is an apterium in the dorso-pelvic tract similar to that in other quail genera. The arrangement of feathers in the ventral and cervical tracts appears to differ from that described for some North American quail.
The chicks hatch with a covering of natal down. Pre-juvenile moult can be seen when the chicks are three days old. Juvenile body plumage is complete in about 30 days; the sides of the face, around the eyes, are the last places to acquire feathers. The tenth and last juvenile primary to grow is mature when the chicks are 41 days old.
The moult in which the juvenile plumage is replaced overlaps the post-natal moult and in part of the ventral tract natal down is replaced by the first adult feathers. This makes it possible to sex the quail at 14 days old. The first adult moult is complete, in the body tracts, by the time the birds are five to six weeks old. The dropping of juvenile primaries commences at about three weeks old and ceases when about eight weeks old. Only from three to six primaries are replaced; most birds studied replaced five. The significance of this difference from other Galliformes is discussed; it is thought to be associated with the species' migratory behaviour. Quail which remained in the controlled laboratory environment did not undergo any further moult. All birds moulted when both temperature and light period were reduced and most birds moulted when the light period alone was reduced. Adult birds housed in small cages in an unheated, unlit shed underwent a complete moult between August and December in which all primaries were replaced. This moult took 8–14 weeks to complete. 相似文献
The chicks hatch with a covering of natal down. Pre-juvenile moult can be seen when the chicks are three days old. Juvenile body plumage is complete in about 30 days; the sides of the face, around the eyes, are the last places to acquire feathers. The tenth and last juvenile primary to grow is mature when the chicks are 41 days old.
The moult in which the juvenile plumage is replaced overlaps the post-natal moult and in part of the ventral tract natal down is replaced by the first adult feathers. This makes it possible to sex the quail at 14 days old. The first adult moult is complete, in the body tracts, by the time the birds are five to six weeks old. The dropping of juvenile primaries commences at about three weeks old and ceases when about eight weeks old. Only from three to six primaries are replaced; most birds studied replaced five. The significance of this difference from other Galliformes is discussed; it is thought to be associated with the species' migratory behaviour. Quail which remained in the controlled laboratory environment did not undergo any further moult. All birds moulted when both temperature and light period were reduced and most birds moulted when the light period alone was reduced. Adult birds housed in small cages in an unheated, unlit shed underwent a complete moult between August and December in which all primaries were replaced. This moult took 8–14 weeks to complete. 相似文献
4.
William. M. Muir P. Bijma A. Schinckel 《Evolution; international journal of organic evolution》2013,67(6):1598-1606
An experiment was conducted comparing multilevel selection in Japanese quail for 43 days weight and survival with birds housed in either kin (K) or random (R) groups. Multilevel selection significantly reduced mortality (6.6% K vs. 8.5% R) and increased weight (1.30 g/MG K vs. 0.13 g/MG R) resulting in response an order of magnitude greater with Kin than Random. Thus, multilevel selection was effective in reducing detrimental social interactions, which contributed to improved weight gain. The observed rates of response did not differ significantly from expected, demonstrating that current theory is adequate to explain multilevel selection response. Based on estimated genetic parameters, group selection would always be superior to any other combination of multilevel selection. Further, near optimal results could be attained using multilevel selection if 20% of the weight was on the group component regardless of group composition. Thus, in nature the conditions for multilevel selection to be effective in bringing about social change maybe common. In terms of a sustainability of breeding programs, multilevel selection is easy to implement and is expected to give near optimal responses with reduced rates of inbreeding as compared to group selection, the only requirement is that animals be housed in kin groups. 相似文献