(54) 2012. Plenary Lecture, 3rd World Congress in Bitechnology, Hyderabad, India (invitation declined).

(53) 2012. 'Aquculture and parasitosis: protozoan infections in finfish' (Public Lecture), Institute of Bioscience, Universiti Putra Malaysia, Serdang, Malaysia.

(52) 2012. 'Strategies against parasitic diseases: the cryptobiosis model' (Plenary Lecture), 3rd Vaccines and Therapeutic Seminar and Workshop: Fish Diseases, Serdang, Malaysia.

(51) 2011. 'Miaminensis avidus, pathobiology and protection' (Public Lecture), Institute of Tropical Aquaculture, Universiti Malaysia Terengganu, Kuala Terengganu, Malaysia.

(50) 2011. Plenary Lecture, 3rd International Symposium on Cage Aquaculture in Asia, Kuala Lumpur, Malaysia (invitation declined).

(49) 2009. 'Relacion entre parasitos protozoarios patogenos y estrategias de defensa del sistema immune: perspectiva para el desarrollo de una vacuna' (Plenary), Seminario Internacional de Parasitologia Applicada a la Acuicultura, Puerto Montt, Chile.

(48) 2009. 'Selected parasitosis in cultured and wild fish' (Plenary; presenter - F.C. Guo), 22nd World Association for the Advancement of Veterinary Parasitology, Calgary, Canada.

(47) 2007. 'Protective immunity in fish against protozoan diseases' (Plenary), 7th International Symposium on Fish Parasites, Viterbo, Italy.

(46) 2005. 'Strategies against piscine parasitosis: the Cryptobia model' (Symposium – Marine Biotechnology: New Uses of Marine Resources), International Conference on Innovations and Technologies in Oceanography for Sustainable Development, Kuala Lumpur, Malaysia.

(45) 2004. 'Salmonid cryptobiosis and strategies against the disease' (Symposium - Protozoan Diseases of Finfish and Their Control), 19th International Congress of Zoology, Beijing, China.

(44) 2004. Symposium Speaker, World and Ehrlich Conference on Magic Bullets, Numberg, Germany (invitation declined; prior commitments).

(43) 2003. 'Control strategies against salmonid diseases' (Plenary), Sustainable Control of Fish Diseases in Aquaculture, Danish Network for Fisheries and Aquaculture Research, Copenhagen, Denmark.

(42) 2002. 'The pathophysiology of piscine and mammalian haemoflagellate diseases' (Symposium - Host Parasite Interactions: A Comparative Approach), American Physiological Society, San Diego, U.S.A.

(41) 2002. 'Salmonid cryptobiosis: prevention and control in experimental infections' (Workshop - Haemoflagellate Diseases), Wageningen University, Wageningen, The Netherlands.

(40) 2002. Cryptobia and cryptobiosis in economically important fishes' (Plenary - Impact and Control of Diseases in Fish), Sustainable Control of Fish Diseases in Aquaculture, Danish Network for Fisheries and Aquaculture Research, Denmark.

(39) 2002. 'Immunological response in Atlantic salmon, and the identification of molecular markers associated with an efficient immune system' Animal Production Theme, AquaNet Meeting, Moncton, Canada.

(38) 2001. 'Fish as an important animal protein and the development of an integrated strategy against piscine parasitosis' (Plenary), International Congress of Parasitology and Tropical Medicine, Kuala Lumpur, Malaysia.

(37) 2001. 'The pathobiology in salmonid cryptobiosis' (Symposium - Infectious Organisms in the Aquatic System: From Molecule to Organism), International Congress of Parasitology and Tropical Medicine, Kuala Lumpur, Malaysia.

(36) 2000. 'Cryptobiosis and its control in North American fishes', 3rd Internet Conference on Salivarian Trypanosomes and Trypanosomatids.

(35) 1999. 'Disease controls in managed fisheries' (Special), University of Malaya, Kuala Lumpur, Malaysia.

(34) 1999. 'Strategies against Cryptobia (Trypanoplasma) salmositica and salmonid cryptobiosis' (Plenary), 5th International Symposium on Fish Parasites, Ceske Budejovice, Czech Republic.

(33) 1998. 'Innate and acquired immunity against parasitic protozoans' (Keynote), Nordic Society for Fish Immunology, Hirtshals, Denmark.

(32) 1998. 'Vaccination against parasitic protozoans in fishes' (Symposium - Control of Parasitic Diseases of Cultured Fish), 9th International Congress of Parasitology, Makuhari Chiba, Japan.

(31) 1998. 'Cryptobia salmositica: protective strategies against the pathogen and disease' (Symposium - International Symposium on Fish Disease), Tokyo University of Fisheries, Tokyo, Japan.

(30) 1998. 'Vaccination against salmonid cryptobiosis' (Workshop - Fish Diseases), National Research Institute of Aquaculture, Mie, Japan.

(29) 1998. Russia/United States Bilateral Symposium on Aquaculture and Fish Health, Rybnoe, Russia (Symposium Speaker: declined invitation ; prior commitments).

(28) 1997. 'The use of monoclonal antibody probes in salmonid cryptobiosis' (Symposium - International Symposium on Research for Aquaculture: Fundamental and Applied Aspects), European Society for Comparative Physiology and Biochemistry, Barcelona, Spain.

(27) 1997. International Society of Developmental and Comparative Immunology, Gloucester Point, Virginia, USA (Symposium: declined invitation; prior commitments).

(26) 1996. 'Acquired immunity in salmonids against experimental cryptobiosis' (Keynote), Malaysian Microbiology Society, Terengganu, Malaysia.

(25) 1996. 'Immunization of Oncorhynchus mykiss against the pathogenic haemoflagellate, Cryptobia salmositica' (Plenary), International Symposium on Fish Vaccinology, International Association of Biological Standardizations, Oslo, Norway.

(24) 1996. 'Salmonid cryptobiosis and protective strategies against the disease', First Internet Conference on Salivarian Trypanosomes

(23) 1995. 'Strategies against salmonid cryptobiosis' (Symposium Speaker - Parasitism in Aquaculture: Strategies for Immunological Control), Canadian Society of Zoologists, Rimouski, Canada.

(22) 1995. 'A tale of my two loves: Trypanosoma and Cryptobia' (Robert A. Wardle Invitational Lecture), Canadian Society of Zoologists, Rimouski, Canada.

(21) 1994. 'Immunity in fish against parasitic flagellates' (Symposium - Immunity Against Parasitic Organisms), 8th International Congress of Parasitology, Izmir, Turkey.

(20) 1994. 'Monoclonal and DNA probes in salmonid cryptobiosis' (Roundtable), 8th International Congress of Parasitology, Izmir, Turkey.

(19) 1993. 'Piscine cryptobiosis and immunological protective strategies: a salmonid experience' (Keynote), Asian Fisheries Society, Phuket Island, Thailand.

(18) 1992. 'Immunosuppression in rainbow trout, Oncorhynchusmykiss, caused by Cryptobia salmositica', 3rd NUS-JSPS Seminar on Fish Biology, Singapore.

(17) 1991. 'Cryptobia and cryptobiosis in freshwater fishes' (Plenary), Brazilian Society of Protozoology, Caxambu, Minas Gerais, Brazil.

(16) 1991. 'Trypanosomiasis in bats' (Roundtable). Brazilian Society of Protozoology, Caxambu, Minas Gerais, Brazil.

(15) 1990. 'Piscine cryptobiosis and mammalian trypanosomiasis in North America' (Symposium - Pathogens and Vectors of Wildlife Diseases), 22nd Annual Conference Society for Vector Ecology, Mesa, U.S.A.

(14) 1990. 'Cryptobia salmositica and salmonid cryptobiosis' (Special), Malaysian Society of Parasitology and Tropical Medicine, Kuala Lumpur, Malaysia.

(13) 1990. 'Experimental cryptobiosis in salmonids' (Workshop), On Salmon Mortality in Lake Michigan, Michigan City, U.S.A.

(12) 1986. 'Acquired immunity against Cryptobia salmositica in rainbow trout, Salmo gairdneri', 6th International Congress of Parasitology, Brisbane, Australia.

(11) 1982. 'Innate and acquired immunity in fishes to haemoflagellates' (Symposium), 5th International Congress of Parasitology, Toronto, Canada.

(10) 1982. 'Host specificity and morphometrics as characters in define of the genus Giardia' (Workshop - on Giardia), 5th International Congress of Parasitology, Toronto, Canada.

(9) 1980. 'Blood flagellates of fishes' (Symposium), Canadian Society of Zoologists, Banff, Canada.

(8) 1976. 'The mechanism of natural resistance of fish to Cryptobia catostomi', 57th Conference of Research Workers in Animal Diseases, Chicago, U.S.A.

(7) 1973. 'The mechanism of the anaemia in experimental Trypanosoma brucei infection', 9th International Congress on Tropical Medicine and Malaria, Athens, Greece.

(6) 1972. 'Immunological techniques in the diagnosis of protozoan diseases in domestic animals' (Symposium), 76th Annual Meeting, U.S. Animal Health Association, Florida, U.S.A.

(5) 1971. 'Tissue forms of African trypanosomes as the cause of some relapses after treatment', 19th World Veterinary Congress, Mexico City, Mexico.

(4) 1970. 'A technique for the parasitological diagnosis of African trypanosomiasis', The Trypanosomiasis Advisory Panel (11th Trypanosomiasis Seminar), Royal Society of Tropical Medicine and Hygiene, London, England.

(3) 1970. 'Animals as reservoir hosts of human trypanosomes' (Symposium), Annual Wildlife Disease Association Conference, Atlanta, U.S.A.

(2) 1969. 'Differences in size between forms of trypanosomes present in blood and in organs', 4th International Conference of World Association for the Advancement of Veterinary Parasitology, Glasgow, Scotland.

(1) 1969. 'Reptiles as possible reservoir hosts for the pathogenic trypanosomes', 1st All Canada Meeting on Tropical and Parasitic Diseases, and Health, Toronto, Canada.