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The heads of animals are given on a reference day during the reference period (see 2.7.3 above).
It is known that the number of livestock in a year may fluctuate. For some animal types (e.g. poultry) there may be a period between production cycles in which the housing is empty, due to temporary breaks in the production cycle (e.g. regular sanitary cleaning of animal houses, disease outbreaks, or similar reasons) and a lower number or no livestock are on the holding.
Because IFS is a structural survey, such holdings should still be recorded to avoid illusionary fluctuations in the data. The livestock of these holdings will correspond to the number of animals just before the sanitary cleaning (provided they no longer exist in any other holding).
Livestock unit
The livestock unit, abbreviated as LSU (or sometimes as LU), is a standard measurement unit that allows the aggregation of the various categories of livestock of various species and age as per convention, via the use of specific coefficients established on the basis of the nutritional or feed requirement of each type of animal, in order to enable a comparison. The coefficients for IFS are adopted in accordance with Annex I of Regulation (EU) 2018/1091.
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