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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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Parameters for Seasonally Breeding Populations
Ecology, 1967Lotka's equations relating the parameters of populations with no seasonal trend in birth rates and Fisher's formula for "reproductive value" are modified to describe populations with restricted annual seasons of birth. The parameters "net reproductive rate" and "mean generation length" provide statistics and dubious utility for populations with ...
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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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Out-of-Season Breeding in Goats
Veterinary Clinics of North America: Food Animal Practice, 1990Maintenance of winter milk production and the production of meat kids for seasonal specialty markets are two major reasons for out-of-season breeding. Strategies include the manipulation of light cycles and the administration of exogenous gonadotrophins following progestogen priming with either vaginal sponges or subcutaneous implants. A number of does
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Breed Differences in the Breeding Season in Sheep
1985The literature has been surveyed for evidence of genetic variation in sexual function of rams throughout the year and in the timing of onset and duration of the breeding season in female sheep. The results of studies on the breeding season of several ewe breeds in Ireland are also presented.
J. F. Quirke, J. P. Hanrahan
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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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Seasonal breeding in female mammals
Mammal Review, 1972SummaryStudy of the causation of seasonal breeding can be subdivided into a consideration of external or ecological, and internal or physiological, factors. Of the ecological ones, the role of day–length has been most extensively studied. Subjecting appropriate animals to different photoperiods should give fresh insight into mechanisms of the central ...
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BREEDING SEASONS IN THE GALAPAGOS.
Ibis, 1950Summary. The Galapagos are on the equator. In the cool and cloudy dry season the south‐east trade wind blows and the cold Humboldt current flows strongly round the islands. In the rainy season, which is very variable but usually lasts from about January to April, the weather is calm, warm and sunny, with periodic heavy rain, while the northern ...
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Breeding for short season environments.
2009AbstractThis chapter discusses the current status of lentil breeding for short season environments. Also discussed are: the production base; production constraints; timing of flowering; history of improvement; breeding objectives; breeding strategy; creation of variability; breeding methods; and future concepts.
M. M. Rahman +5 more
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Breeding seasons in feral pigeons
1995Abstract Reproduction in birds involves a large number of behavioral and endocrinological events in complex ecologic settings. In no other aspect of avian biology must so many hormonal and behavioral variables satisfactorily interact with environments that are not wholly predictable.
Richard F Johnston, Marián Janiga
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