Sex ratio of offspring in domestic animals: Swine (6)
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چکیده
منابع مشابه
Sex-ratio evolution in sex changing animals.
Sex allocation theory is often able to make clear predictions about when individuals should facultatively adjust their offspring sex ratio (proportion male) in response to local conditions, but not the consequences for the overall population sex ratio. A notable exception to this is in sex changing organisms, where theory predicts that: (1) organisms should have a sex ratio biased toward the "f...
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Pre-determining fetal sex is against the random and equal opportunity that both conceptus sexes have by nature. Yet, under a wide variety of circumstances, populations shift their birth sex ratio from the expected unity. Here we show, using fluorescence in situ hybridization, that in a population of pygmy hippopotamus (Choeropsis liberiensis) with 42.5% male offspring, males bias the ratio of X...
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tends to have a predictable effect on smoking cessation. However, from a social perspective, it is fairly certain (to within relatively narrow confidence limits) how many cases of lung cancer or cardiac events will be avoided if 10000 persons stop smoking. What this illustrates is that social benefit is more certain than individual benefit. In other words, if we are concerned with a social pers...
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In this study, I predict that the global variation of offspring sex ratio might be influenced in part by the level of parasite stress. From an energetic standpoint, higher gestational costs of producing a male offspring could decrease male births in a population with limited resources. This implies that, any factor that limits the parental resources could be expected to favor female offspring p...
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There is evidence that the ratio of the length of the 2nd and 4th digit (2D:4D) is negatively related to prenatal and adult concentrations of testosterone. It has also been reported that high levels of testosterone at conception in both fathers and mothers are associated with an increased sex ratio (proportion of males at birth). It follows from these observations that low values of 2D:4D may b...
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ژورنال
عنوان ژورنال: The Japanese journal of animal reproduction
سال: 1976
ISSN: 0453-0551
DOI: 10.1262/jrd1955.22.106