Forced Copulation in Captive Mallards I. Fertilization of Eggs
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چکیده
BERTRAM, B.C. R. 1980. Vigilance and group sizes in ostriches. Anim. Behav. 28: 278-286. CARACO, T. 1979a. Time budgeting and group size: a test of theory. Ecology 60: 618-627. 1979b. Time budgeting and group size: a theory. Ecology 60: 611-617. 1980. Stochastic dynamics of avian foraging flocks. Amer. Natur. 115: 262-275. --, S. MakRTINDALE, & H. R. PULLIAM. 1980. Avian flocking in the presence of a predator. Nature 285: 400-401.
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Transfer of Maternal Antibodies against Avian Influenza Virus in Mallards (Anas platyrhynchos)
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