2001 Fiscal Year Final Research Report Summary
Studies on the mechanism of eggshell formation in the guineafowl
| Project/Area Number |
12660249
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Zootechnical science/Grassland science
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| Research Institution | Junior College of Tokyo University of Agriculture |
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Principal Investigator |
OGAWA Hiroshi Junior College of Tokyo University of Agriculture, Department of Bioproduction Technology, Associate Professor, 生物生産技術学科, 助教授 (30151533)
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| Co-Investigator(Kenkyū-buntansha) |
KUWAYAMA Takehito Toyo University of Agriculture, Faculty of Agriculture, Assistant Professor, 農学部, 講師 (40215124)
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| Project Period (FY) |
2000 – 2001
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| Keywords | guineafowl / egg formation / eggshell gland / eggshell formation / mineral / parathyroid hormone receptor / calcitonin recedptor |
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| Research Abstract |
Mechanism of the eggshell formation was examined in the guineafowl.
1) The greater thickness and weight of the shell portion of the egg in the guineafowl may result from the deposition of a larger amount of minerals on the surface of a thicker shell membrane.
2) Egg size is determined at 8 hours of stay in the uterus in both the guineafowl and the chicken.
3) The smaller size and the smaller amount of albumen in the guineafowl egg may be due to smaller binding capacity of the estrogen receptor in the oviduct magnum and less plumping during the first 8 hours of stay in the uterus.
4) No appreciable change of the weight of the eggshell and whole egg was observed from 38 to 70 weeks of age in the guineafowl. Thicker eggshell and greater strength of the eggshell were maintained during the period.
5) Great amount of minerals may be due to the longer period of shell formation in the guineafowl.
6) Parathyroid hormone (PTH) receptor binding property in the membrane fraction of the endometrium of the shell gland (uterus) of the guineafowl was analyzed by the use of [^<125>I]PTH-related peptide binding assays.The results suggest that PTH/PTHrP receptors are present in the shell gland of the guineafowl and their binding may be related to eggshell formation.
7) Radioligand binding assays of membrane fraction of the shell gland endometrium of the guineafowl revealed the presence of receptor for calcitonin. The change in the binding affinity and capacity of CT receptor may be related to the eggshell formation in the shell gland of the guineafowl.
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Research Products
(4 results)
