Safety and efficacy of sodium selenate as feed additive for ruminants

nutritional additives, compounds of trace elements, selenium, sodium selenate,ruminants, safety, efficacy
First published in the EFSA Journal
22 July 2019
3 July 2019
Scientific Opinion

Relevant information or parts of this scientific output have been blackened in accordance with the confidentiality requests formulated by the applicant pending a decision thereon by the European Commission. The full output has been shared with the European Commission, EU Member States and the applicant. The blackening will be subject to review once the decision on the confidentiality requests is adopted by the European Commission.


Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of sodium selenate as a nutritional feed additive for ruminants, when used via an intraruminal bolus in ruminants. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) Panel concludes that based on (i) the estimation of the release of selenium from the bolus, (ii) the similarities in bioavailability with sodium selenite, (iii) the experience with the use of boluses in ruminant nutrition and (iv) the wide margin of safety compared with the maximum tolerable levels of selenium in ruminants, the additive is safe for ruminants. The use of sodium selenate by bolus administration providing a selenium intake not exceeding that resulting from the maximum authorised EU level of total selenium in feed presents no concerns for consumer safety. The additive does not pose a risk to users by inhalation and is considered as non‐corrosive but irritant for the skin and the eyes. The FEEDAP Panel considers the additive as a skin sensitiser and respiratory sensitiser. The additive under assessment, in its intended use as complementary feed for ruminants in the form of boluses, is a substitute for other authorised selenium additives and will not further increase the environmental burden of selenium. Based on two studies submitted in cattle and sheep and studies from the literature, the FEEDAP Panel concludes that sodium selenate delivered by a bolus to ruminants is an efficacious source of selenium in meeting the animals’ requirements. The Panel posed some recommendations regarding the use of the bolus, especially in small size ruminants. The Panel also posed a remark, concerning the zinc content of the bolus from which the additive is delivered.

Panel members at the time of adoption

Giovanna Azimonti, Vasileios Bampidis, Maria de Lourdes Bastos, Henrik Christensen, Birgit Dusemund, Maryline Kouba, Mojca Kos Durjava, Marta López‐Alonso, Secundino López Puente, Francesca Marcon, Baltasar Mayo, Alena Pechová, Mariana Petkova, Fernando Ramos, Yolanda Sanz, Roberto Edoardo Villa and Ruud Woutersen
Panel on Additives and Products or Substances used in Animal Feed
feedap [at]
EFSA Journal 2019;17(7):5788
Question Number
On request from
European Commission