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Feed Additives: Do They Add to Animal Welfare? An Evaluation

Published online by Cambridge University Press:  11 January 2023

C J Kan ,
L P Jager  and
F J Grommers
C J Kan*
Affiliation:
Institute for Animal Science and Health (ID-DLO), Postbus 65, 8200 AR Lelystad, The Netherlands
L P Jager
Affiliation:
Institute for Animal Science and Health (ID-DLO), Postbus 65, 8200 AR Lelystad, The Netherlands
F J Grommers
Affiliation:
Faculty of Veterinary Medicine, University of Utrecht, Interdepartmental Section of Veterinary Medicine and Society, Postbus 80.151, 3508 TD Utrecht, The Netherlands
*
† Contact for correspondence and requests for reprints
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Abstract

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The welfare of farm animals is strongly influenced by the man-made environment. Welfare problems also arise from reduced homeostatic capacities in animals. Feed additives, used to promote growth or to prevent diseases can alter the animals' self-regulating capacities thus affecting their welfare. The EU regulates the use of these additives within specified groups of Directive 70/524/EEC. Although these feed additives can be regarded as prescription-free veterinary drugs, critical remarks on their desired and adverse effects have received little attention.

A survey of the available literature shows that about one-third of licensed feed additives alter adrenal function in vitro. Reports of the adverse effects of anticoccidial additives in vivo suggest they can be classified under three headings: (i) substances with a very narrow safety margin (the difference between the permitted dose and the dose with adverse effects) and often irreversible effects on growth and feed conversion; (ii) substances with a narrow safety margin and largely reversible effects; (iii) substances with an adequate safety margin. The growth promoters (including antibiotic growth promoters) can - on the basis of their adverse effects - be classified into two groups: (i) substances with a very narrow safety margin; and (ii) substances with an adequate safety margin.

On the one hand, animal welfare considerations require use of disease-preventing additives, but on the other hand, they also demand discontinuation of current practices. Judicious use of additives can add to animal welfare. However, their unlimited use to obscure defects in husbandry is detrimental to animal welfare. A major obstacle to the judicious use of feed additives, is the lack of published, unbiased information on their efficacy and safety for farm animals.

Keywords

animal welfareantimicrobialscattlecoccidiostatsgrowth promoterspigspoultry
Type
Research Article
Information
Animal Welfare , Volume 7 , Issue 4 , November 1998 , pp. 397 - 414
Copyright
© 1998 Universities Federation for Animal Welfare

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