ABSENCE OF XENIA IN OSTRICH EGGS
نویسندگان
چکیده
منابع مشابه
Evolution of bird eggs in the absence of cuckoo parasitism.
Historical introductions of species into new habitats can create rare opportunities to test evolutionary hypotheses, such as the role of natural selection in maintaining traits. This study examines two independent introductions of the African village weaverbird (Ploceus cucullatus) to islands where selection on egg appearance traits is expected to differ markedly from that of the source populat...
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Abstract Nutrition of breeding female birds can influence egg quality and is therefore extremely important for the development of the embryo and the successful hatching of a high quality chick. We investigated the effect of combining different levels of dietary energy and protein, with accompanied amino acid levels, in the diets of female ostriches on the composition of their eggs. Ninety pairs...
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The present study was carried out with the aim of determining the effects of storage temperature and storage position on embryonic mortalities in ostrich eggs. A total of 229 ostrich eggs was collected from two commercial ostrich farms. The effects of storage temperature on embryonic mortality differed. Embryonic deaths (totalled for early, medium and late incubation) were determined at respect...
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The ostrich industry experiences a high rate of embryonic mortalities during artificial incubation of eggs. Embryonic deaths were studied from data recorded on 37,740 fertile eggs incubated artificially during the 1998-2005 breeding seasons. Roughly 10,000 eggs that sustained embryonic mortalities were classified according to the stage and nature of death, i.e. before 21 days of incubation, aft...
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ژورنال
عنوان ژورنال: Journal of Heredity
سال: 1918
ISSN: 1465-7333,0022-1503
DOI: 10.1093/oxfordjournals.jhered.a111953