Results 161 to 170 of about 70,068 (218)
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Inherent seasonality in the breeding seasons of African mammals: evidence from captive breeding
Transactions of the Royal Society of South Africa, 2002Breeding records from zoos provide a virtually untapped source of information for determining reproductive patterns of species unconstrained by nutritional variables and may be important in planning conservation strategies for rare species for which little “wild” data exist.
J. D. SKINNER, D. G. MOSS, D. C. SKINNER
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On the breeding season in the sheep
The Journal of Agricultural Science, 1944Ewes. There was some variation from year to year in the times of onset and end of the breeding season; on the average it was evenly spaced on either side of the shortest day. Occasionally ewes were served and became pregnant at times well outside the normal limits of the breeding season.
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Nature, 1937
IT has recently been shown by Marshall and Bowden1 that not only duration but also intensity of illumination can affect the onset of a breeding season, and that ultra-violet as well as visible light is effective. These discoveries have an important bearing on seasonal phenomena in the tropics.
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IT has recently been shown by Marshall and Bowden1 that not only duration but also intensity of illumination can affect the onset of a breeding season, and that ultra-violet as well as visible light is effective. These discoveries have an important bearing on seasonal phenomena in the tropics.
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THE DURATION OF THE BREEDING SEASON OF FOUR BREEDS OF SHEEP
Canadian Journal of Animal Science, 1974Three breeds of sheep (Dorset, Leicester, and Suffolk) and a crossbred line from these breeds (DLS) were observed throughout 1 yr to determine their sexual activity by daily exposure of the ewes to vasectomized rams. The DLS and Dorset ewes exhibited their first estrus earlier in the year (P < 0.01) and stopped cycling later than the Leicester and ...
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Seasonal Variation in the Breeding Activity of Rams
Nature, 1965MOST investigations into the breeding season, of sheep in Britain have been concerned with the behaviour of females. Little attention has been paid to the desire or ability of males to mate at different times of the year, for it is generally considered that under temperate conditions there is no discernible non-breeding season in rams of the British ...
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Photoperiodic Regulation of Seasonal Breeding in Birds
Annals of the New York Academy of Sciences, 2005Abstract: Day length‐dependent breeding in birds commonly occurs in spring and summer, but may occur after exposure to complex changes in day length, as for example in transequatorial migrants. More rarely, some photoperiodic birds breed when day lengths are decreasing or are short.
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The Journal of Agricultural Science, 1952
A knowledge of the exact length of the breeding season for improved breeds under different environmental conditions in this country is lacking. Such knowledge is of importance so that the lambing season can be arranged according to farm conditions.
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A knowledge of the exact length of the breeding season for improved breeds under different environmental conditions in this country is lacking. Such knowledge is of importance so that the lambing season can be arranged according to farm conditions.
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Breeding season of Octopus vulgaris
Marine Biology, 1972Female Octopus vulgaris Cuvier mated in the laboratory in every month tested. Females maintained in isolation after capture and not mated in the laboratory laid eggs, fertile and infertile, each month of the year. The longest period of sperm viability was 104 days. Young specimens weighing between 4.0 and 66.0 g were found regularly.
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