Dr Gilbert Jeyaruban
Scientist - Animal Genetics and Breeding Unit (AGBU)
Phone: +61 2 6773 2879
Email: gjeyarub@une.edu.au
Biography
I have over 34 years of experience in research and development of improving the genetic potential of beef, goats, dairy and poultry in developed and as well as in developing countries. My current research is focused on developing genetic evaluation for beef cattle in Australia to improve their productivity.
Gilbert has over 34 years of experience in research and development of improving the genetic potential of beef, goats, dairy and poultry in developed and, as well as, in developing countries. Gilbert’s current research is focused on developing genetic evaluation for beef cattle in Australia to improve their productivity. Introduction of new traits into BREEDPLAN, which requires expert analysis of large datasets to understand the genetic architecture of each trait and how each trait is related to all others genetically. In non-technical terms, this means determining the extent to which differences in animals’ genes are reflected in differences in observed performance, and the extent to which genes affecting one trait also affect other traits. These parameters are the heritability of a trait and the genetic correlations between traits respectively, and these parameters are used in the analysis of large industry datasets from which estimates of the value of each animal’s genes for each trait (these estimates are known as Estimated Breeding Values, or EBVs, and the basic language of genetic improvement in beef cattle in this country). Obtaining reliable estimates of the parameters for each breed is a meticulous analytical skill, essential to ensuring reliable EBVs.
This reliability is essential to ensuring that bull breeders and commercial producers can trust the EBVs, and make use of them in their breeding decisions. BREEDPLAN currently generates c. 30 EBVs per breed, with over 200,000 new animals being submitted for evaluation each year in Australia. Industry impact statistics show that use of BREEDPLAN has increased (volume of animals, amount of genetic improvement) by 35% between 2011-2015 and 2016-2020 – indicating increasing trust in the EBVs – which in turn reflects faith in the underlying analysis, for which the genetic parameters are central.
Gilbert has lead the development of a large number of new traits for BREEDPLAN through the last decade, as well as re-estimating the parameters for existing sets of traits as large volumes of new data are added. As such Gilbert is directly responsible for this accuracy that the industry has come to expect and rely on.
As someone operating as a level D academic, Gilbert is also one of the stand-out scientists within AGBU in supervision of post-graduate students. Gilbert has taken on several students in recent years within AGBU’s growing post-grad program. These students have required more than “standard” supervisor input reflecting challenges with English language and technical development required – however, all have graduated successfully, and grow AGBU networks domestically and internationally. Gilbert is a true mentor to these students, sticking with them through the challenges that are characteristic of this area and see that they not only complete, but also publish successfully.
Qualifications
1992 Doctor of Philosophy, University of Guelph, Canada.
1985 Bachelor of Veterinary Medicine, University of Peradeniya, Sri Lanka.
Research Interests
Gilbert is involved in the research and development of BREEDPLAN for beef cattle genetic evaluation in Australia and overseas.
Publications
Refereed Journal Articles
Jeyaruban, M G; Tier, B; Johnston, D J and Graser, H-U (2012). “Genetic analysis of feet and leg traits of Australian Angus cattle using linear and threshold models.” Animal Production Science 52(1):1-10 doi.org/10.1071/AN11153.
Jeyaruban, M G and Rahman, M H (2010). “Proposed breeding structure for cattle development in countries in the South Asia Pacific region.” Selection in Asia: and Breeding of Cattle Strategies and Criteria for Improved Breeding, IAEA TEC DOC-1620 pp.25-34.
Jeyaruban, M G; Johnston, D J and Graser, H-U (2009). “Estimation of genotype x environment interactions for growth, fatness and reproductive traits in Australian Angus cattle.” Animal Production Science 49:1-8.
Jeyaruban, M G and Gibson, J P (1996). Estimation of additive genetic variance in commercial layer poultry and simulated populations under selection. Theor. Appl. Genet. 92:483-491.
Jeyaruban, M G; Gibson, J P and Gowe, R S (1995). Comparison of Index Selection and Best Linear Unbiased Prediction for Simulated Egg Type Poultry Data. American Poultry Science 74, 10.
Book Chapters and Reviews
Tongsiri, S and Jeyaruban, M G (2014). “Performance and resilience of poultry in Thailand.” In S Hermesch and S Dominik (Eds.), Breeding Focus 2014 – Improving Resilience, pp 65-72, Armidale, NSW: University of New England.
Jeyaruban, M G; Abeygunawardana, H and Chandrasiri, A D N (2000). Scientific Basis of Genetic Improvement. In Cattle and Buffalo Farming. Handbook for Veterinarians. National Science Council, Sri Lanka. Publication. 201-207.
Abeygunawardana, H; Perera, B M O A; Jeyaruban, M G and De S. Sriwardana, J A (2000). Breeding of Buffaloes and Cattle. In Cattle and Buffalo Farming. Handbook for Veterinarians. National Science Council, Sri Lanka. Publication. 208-217.
Jeyaruban, M G; Senyatso, E K; Podisi, B; Mosimanyana, B M and Norris, D (2000). Manual for Small Stock Breeding Programme. Animal Production and Ranch Research Division, Department of Agricultural Research.
Jeyaruban, M G and De S. Gamage, D V S (1993). Role of state sector in poultry industry. In Status of Poultry Industry in Sri Lanka and Scope for its Expansion. Ed. D.D. Wanasinghe. Sri Lanka Veterinary Association.
Conference Proceedings
Beef Cattle
Jeyaruban, M G and Johnston, D J (2014). Estimated additive and non-additive breed effects and genetic parameters for ultrasound scanned traits of a multi-breed beef population in tropical Australia.”  In Proceedings of the 10th World Congress on Genetics Applied to Livestock Production, Vancouver, Canada, 17-22 August. Paper 241.
Jeyaruban, M G and Johnston, D J (2013). “Genetic associations of early growth and ultrasound scanned traits in several beef breeds.” Proc. Assoc. Advmt. Anim. Breed. Genet. Napier, New Zealand, July 20-23. 20:249-252.
Weerasinghe, W M S P; Gondro, C; Jeyaruban, M G; Mwai, O; Mujibi, D F and Gibson, J P (2013). “The prediction of genetic structure of East African smallholder dairy cattle.” Proc. Assoc. Advmt. Anim. Breed. Genet. Napier, New Zealand, July 20-23. 20:163-166.
Barwick, S A; Jeyaruban, M G; Johnston, D J; Wolcott, M L and Graser, H-U (2011). “The impacts on selection for economic merit of including residual feed intake traits in breeding objectives and of having records available.” Proceedings of the 19th Conference of the Association for the Advancement of Animal Breeding and Genetics. Perth, Western Australia. July 19 - 21. pp.43-46.
Jeyaruban, M G; Johnston, D J and Graser, H-U (2011). “Comparison of genetic parameters for calving difficulty in Angus, Charolais, Hereford and Limousin.” Proceedings of the 19th Conference of the Association for the Advancement of Animal Breeding and Genetics. Perth, Western Australia. July 19 - 21. pp.119-122.
Jeyaruban, M G; Wolcott, M L; Johnston, D J and Graser, H-U (2011). “Effect of previous reproductive status of dam on the preadjustment of weaning weight for genetic evaluation in tropical beef breeds.” Proceedings of the 19th Conference of the Association for the Advancement of Animal Breeding and Genetics. Perth, Western Australia. July 19 - 21. pp.59-62.
Barwick, S A; Graser, H-U; Jeyaruban, M G; Johnston, D J and Wolcott, M L (2010). “Review of potential investment into recording feed efficiency in beef cattle”. MLA Project B.BFG.0050 Workshop, University of New England, Armidale, 3 June, 35 pp.
Jeyaruban, M G; Johnston, D J and Graser, H-G (2009). “Genetic association of net feed intake measured at two stages with insulin-like Growth Factor-I, growth and ultrasound scanned traits in Angus cattle.” Proceedings of the 18th Conference of the Association for the Advancement of Animal Breeding and Genetics. Barossa Valley, South Australia. September 28-October 1. pp.584-587.
Jeyaruban, M G; Johnston, D J and Graser, H-U (2007). “Development of a genetic evaluation system for structural soundness traits in Angus cattle.” Proceedings of the 17th Conference of the Association for the Advancement of Animal Breeding and Genetics. Armidale, Australia. September 24-26. pp.391-394.
Jeyaruban, M G; Mosimanyana, B M and Setshwaelo, L L (2002). Utilization of indigenous breeds for sustainable beef production under semi-arid conditions in Botswana. 7th World Congress on Genetics Applied to Livestock Production. Montpellier, France.
Jeyaruban, M G and Mosimanyana, B M (2002). Herd recording for genetic improvement of beef animals. Proceedings of the 2nd National Agricultural Research Forum. Gaborone, Botswana.
Jeyaruban, M G; Phiri, L and Mosimanyana, B M (2001). The Tswana: A potential beef breed for sub-Saharan climate. 1st National Agricultural Research Forum. Gaborone, Botswana.
Phiri, L and Jeyaruban, M G (2001). Efficiency of Suckler Cows of Tswana, Tuli and Brahman Breeds. 1st National Agricultural Research Forum. Gaborone, Botswana.
Jeyaruban, M G; Mosimanyana, B M and Pelaelo, D (2000). Economic return from Tswana cattle under ranch management in the southern part of Botswana. Annual scientific seminar of the Department of Agricultural Research. Sebele, Gaborone, Botswana.
Jeyaruban, M G and Mosimanyana, B M (2000). Genetic parameters and genetic change for growth traits in a selected Tswana population. Annual scientific seminar of the Department of Agricultural Research. Sebele, Gaborone, Botswana.
Jeyaruban, M G and Mosimanyana, B M (1999). Beef cattle breeding research in Botswana: Present status and future strategies. Annual scientific seminar of the Department of Agricultural Research. Sebele, Gaborone, Botswana.
Kgati, L M; Mosimanyana, B M and Jeyaruban, M G (1999). Performance of the Bonsmara beef cattle in two different agro-ecological regions in Botswana. Annual scientific seminar of the Department of Agricultural Research. Sebele, Gaborone, Botswana.
Poultry
Tongsiri, S; Jeyaruban, M G; van der Werf, J H J and Thummnbood, S (2014). “Genetic parameters for production traits of Rhode Island Red and White Plymouth Rock breeds selected under tropical conditions in Thailand.” In Proceedings of the 10th World Congress on Genetics Applied to Livestock Production, Vancouver, Canada, 17-22 August. Paper 854.
Jeyaruban, M G; De S. Gamage, D V S; Senadera, P G L and Irriyagama, C K (1996). Egg production curve of the locally developed white egg-laying strain. In Proceedings of the 48th Annual Scientific Session, Sri Lankan Veterinary Association. Kandy, Sri Lanka.
Jeyaruban, M G; Gunaratne, S P; De S. Gamage D V S and Giritharan, G (1995). Selection for higher egg production and egg weight in poultry under tropical conditions. In Proceedings of the 47th Annual Scientific Session, Sri Lanka Veterinary Association. Colombo, Sri Lanka.
Jeyaruban, M G and Gibson, J P (1994). Effects of population size and the mating ratio on the economic response and inbreeding of egg laying poultry. In Proceedings of the 5th World Congress on Genetics Applied to Livestock Production. Guelph, Canada.
Gibson, J P and Jeyaruban, M G (1993). The effects of BLUP evaluations, population size and restrictions on selection of close relatives on response and inbreeding in egg laying poultry. 42nd Breeders Roundtable. St Louis Missouri, USA.
Gibson, J P and Jeyaruban, M G (1993). BLUP evaluations and the balance between response and inbreeding in egg laying lines of poultry. 10th International symposium on current problems in animal genetics "AVIAGEN". Nitra, Slovakia.
Gamage, D V S and Jeyaruban, M G (1992). Estimation of genetic parameters in unselected foundation stock at the Central Poultry Research Station in Sri Lanka. In Proceedings of the 45th Annual Scientific Session of the Sri Lanka Veterinary Association. Sri Lanka Veterinary Journal 40,1.
Jeyaruban, M G and Gibson, J P (1990). Change in genetic parameters over generations in a selected population of poultry. In Proceedings of the 79th Annual Scientific Meeting of the Poultry Science Association. Virginia, USA.
Goats
Jeyaruban, M G; Zuhry, A M and Senadeera, L (1998). Genetic aspect of goat breeding in the dry zone of Sri Lanka. In Proceedings of the 49th Annual Scientific Session of the Sri Lanka Veterinary Association. Colombo, Sri Lanka.
Jayasinghe, S L and Jeyaruban, M G (1993). Characterization of growth and reproductive parameters of Sri Lanka Boer. In Proceedings of the 46th Annual Scientific Session, Sri Lankan Veterinary Association. Kandy, Sri Lanka.
Jeyaruban, M G and Weerasekera, N B (1992). Genetic potential of several goat breeds and their crosses in Sri Lanka. In Proceedings of the 45th Annual Scientific Session of the Sri Lanka Veterinary Association. Sri Lanka Veterinary Journal 40,1.
Jeyaruban, M G and Rajasekeram, V (1990). Genotype environment interaction on exogenous hormone treatment in meat goat breeds. In Proceedings of the 48th Annual Scientific Session of the Sri Lanka Veterinary Association. Kandy, Sri Lanka.
Dairy Cattle
Jeyaruban, M G and Gibson, J P (2012). "Performance of Friesian, Jersey and their crosses under smallholder dairy production systems in tropics: a meta analysis." 15th AAAP Animal Science Congress, Bangkok, Thailand, 26 - 30 November 2012, 2:247-250.
Weerasinghe, W M S P; Condro, C; Jeyaruban, M G; Henshall, J M and Gibson, J P (2012). "Genetic structure and diversity of Australian sheep breeds." 33rd Conference of the International Society of Animal Genetics, Cairns, Australia, 15 - 20 July 2012.
Weerasinghe, W M S P; Condro, C; Henshall, J M; Jeyaruban, M G and Gibson, J P (2012). "Accuracy of estimation of breed composition using marker data in crossbred sheep." 15th AAAP Animal Science Congress, Bangkok, Thailand, 26 - 30 November 2012.
Jeyaruban, M G and Kumarasamy, C (1998). Lactation curves of some of the dairy breeds in Sri Lanka. In Proceedings of the 49th Annual Scientific Session of the Sri Lanka Veterinary Association. Colombo, Sri Lanka.
Jeyaruban, M G (1994). Dairy development in tropics. In Proceedings of the CEC mid term workshop. Gannoruwa, Peradeniya, Sri Lanka.
Jeyaruban, M G; Bandara, T and Peiris, H J (1993). Comparison of production and reproduction parameters of crossbred sahiwals in dry zone of Sri Lanka. In Proceedings of the 46th Annual Scientific Session of the Sri Lanka Veterinary Association. Kandy, Sri Lanka.
Buffalo
Mohamed, A R; Jeyaruban, M G; Vercoe, J E and Frisch, J E (1994). Effects of supplementary feeding and environment on the reproductive performance of buffaloes in dry zone of Sri Lanka. In Proceedings of the 41st Annual Scientific Session of the Sri Lanka Veterinary Association. Sri Lanka Veterinary Journal 36, 53.
Mohamed, A R and Jeyaruban, M G (1991). Reproductive performances and body weight changes of the Lankan and Murrah buffalo in Sri Lanka. In Buffalo and Goats in Asia: Genetic diversity and its application. Ed. N.M. Tulloch. ACIAR proceedings. 34.
Mohamed, A R and Jeyaruban, M G (1989). A comparative study of reproductive performance of Lanka and Murrah buffaloes under two nutritional regimes. ACIAR Annual Session. Rockhampton, Australia.
