1. 10th International Congress of Toxicology (ICT X-2004); 11-15 July, 2004, Tampere, Finland.
2. Bioavailability of Micronutrients in Relation to Public Health (Bioavailability 2001); Switzerland, Interlaken, May 29-June 1, 2001.
3. 5th European Arab Veterinary Association Conference; Khartoum, Sudan, January (2001).
4. 8th Arab Veterinary Association Conference; Khartoum, Sudan (1998).