Turkey Conference Looks into the Future of Breeding

Two papers presented at the Turkey Science and Production Conference earlier this year focussed on developments in the field of genomics and how the breeding companies are applying this knowledge to develop products for the future, writes Jackie Linden, editor of ThePoultrySite.
calendar icon 19 May 2010
clock icon 5 minute read

Turkey Genome Sequencing

Next generation sequencing technologies have been used to sequence the genome of the turkey rapidly and efficiently, explained Dr David Burt of the Roslin Institute and Royal (Dick) School of Veterinary Studies in Edinburgh.

The current genome assembly, he said – which comprises 1.1 billion base pairs – includes 917 million base pairs of sequences assigned to specific chromosomes. Innate heterozygosity of the sequenced bird – a female known as Nici donated by Nicholas Turkey Breeding Farms – has allowed the discovery of more than 600,000 high-quality single nucleotide variants. Annotation pipelines predicted nearly 16,000 genes, with 15,093 recognised a protein-coding and 611 non-coding RNA genes, said Dr Burt.

Comparative analysis of the turkey, chicken and zebra finch genomes, and comparisons also with mammals, support the notable stability of avian genomes and has identified a number of genes unique to birds.

"It will soon become possible to select for multiple traits based on phenotypes and genotypes of larger groups of animals, and thus set the foundation of the next generation of commercial turkeys"

Clear differences are seen in the number and variety of genes of the immune system where gene duplication events are less frequent in birds than gene losses.

The turkey genome provides resources to further understand the evolution of avian genomes, said Dr Burt, as well as the reference to discover genetic variations underlying economically important quantitative traits.

Still looking to the future, he added that breeding companies will be able to apply the information on the genome for genetic selection based on DNA markers. If the costs for genotyping panels come down sufficiently, it will soon become possible to select for multiple traits based on phenotypes and genotypes of larger groups of animals, and thus set the foundation of the next generation of commercial turkeys.

In response to a question, Dr Burt explained that these developments will be useful for traits that are expensive to measure (such as feed intake, eggs production or disease resistance), those that are sex-limited (such as fertility), and those that are important either post mortem (e.g. meat quality) or later in life (for example, liveability or lifetime egg production). He identified the expected benefits as increasing the accuracy of estimated breeding value (EBV) and of genetic gain by 20 to 40 per cent, while reducing the number of animals tested and the rate of inbreeding.

Breeding Company's View: Turkey Products for the Future

"Marker Assisted Selection has opened up a whole new dimension for future breeding programmes"

In his presentation, Dr Magnus Swalander of Aviagen Turkeys explained how the breeding companies are working with the turkey industry to develop products for the future.

He began by stating that the goal of the primary breeding companies is to maximise genetic progress in the field, emphasising that nowadays, selection is balanced for meat production, reproductive efficiency, health and welfare-related traits. These principles can be applied to both improving existing products and the development of test products. Dr Swalander explained that these sources are used to create a test product, which is tested in successive years in-house, then in the field, then in extended field tests with customers and finally in large-scale commercial field tests before the product is finally released. This process can take at least six years.

After outlining the information tools available – global customer databases, pen trials, customer feedback and pedigree genetic trends – he went on to highlight the tremendous genetic progress that has been achieved with commercial turkeys, giving the example of how the feed conversion of heavy turkeys has been reduced from 2.82 in 1999 to 2.55 in 2009. Various innovations are being used to achieve faster genetic progress, he explained.

Looking to the future, Dr Swalander confirmed that the primary breeders will continue to work in this way with the industry in future. In Europe, more extensive databases will help both product and technical development.

The supply of poultry breeding stock for a wide variety of markets and environmental conditions has been a driver for the evolution of balanced breeding goals, he said, adding that selection is being applied to an ever wider range of characteristics, including fitness/welfare traits, efficiency, reproductive performance and quality traits (meat quality and feathering).

Marker Assisted Selection has opened up a whole new dimension for future breeding programmes, said Dr Swalander, and genomics can increase the accuracy of selection for a range of traits, including those that are sex-linked, expensive to record or those expressed only in commercial environments, such as diseases resistance.

Dr Swalander concluded that he anticipates future product development strategies to be based on a combination of genomics and existing routine selection tools.

Further Reading

- You can view our previous article from the Turkey Science and Production Conference 2010 by clicking here.

May 2010
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