Surveys of egg yields in England and Wales, 1948-69
Titel:
Surveys of egg yields in England and Wales, 1948-69
Auteur:
Orton, C. R.
Verschenen in:
British poultry science
Paginering:
Jaargang 12 (1971) nr. 1 pagina's 15-24
Jaar:
1971-01
Inhoud:
For many years the Ministry of Agriculture, Fisheries and Food has collected statistics on egg yields of poultry flocks on agricultural holdings in England and Wales, by means of sample surveys. Within a basic framework of stratified random sampling, the surveys have varied over the years, both in sample design and in questions asked. Other bodies, in particular the British Egg Marketing Board and the Poultry Association of Great Britain, have carried out similar surveys of their own, but differences in definition and coverage make comparisons difficult. The surveys have shown a generally rising level of yields, due partly to the swing to intensive systems of management and partly to an improvement in yields within the systems of management. There has been a large swing towards the battery system, which is losing momentum as the majority of laying fowls are now kept in this system. Each system of management has a recognisable seasonal pattern of yields: the overall pattern has changed with the changing proportions of the systems.
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