Research & Development – Landcatch
This page: selecting the broodstock for breeding at Ormsary.
Far page – clockwise from top: Landcatch smolts; MD Neil Manchester; Hatchery Manager, Kasi Rajan; (l-r) Head of Quantitative Genetics, Derrick Guy; Head of Molecular Biology, Alastair Hamilton; Director of Genetics, Alan Tinch; Head of Freshwater Production, David Danson; Head of Broodstock Production, Keith Drynan; Sites Manager (South), Tam Lynch
we know how fast they grow. We also measure fat content, length, condition factors and we take a note of the presence or absence of any deformities, as well as the general quality and appearance of the fish. ‘When we are collecting data for harvest, we create special populations that are put through a normal commercial processing operation, so in those populations we’ll gather data on weight, length and fat content, but also colour, fillet weight, fillet yield and gutted yield. Ultimately it’s like a very large dating agency – we’ll cross the best males with the best females to improve their
32
performance in the field, either on farms or in processing.’ Whilst growth rates and performance are key factors in the Landcatch breeding programme, it is in the area of disease where the genetics has really come to the fore. ‘Disease resistance was actually the main driver for the breeding programme,’ says Tinch. ‘In the late ‘90s the Scottish, European and indeed global salmon farming industry had a real problem with IPN, and we started the breeding pro- gramme on that basis.’ So alongside the other traits, the genetics team at Landcatch began measuring
for robustness and disease resistance. They exposed certain populations to disease in a controlled way, and recorded susceptibility and resistance within that population and brought that information back into the breeding programme. They now have a lot of data regarding which of their broodstock families are most resistant to IPN. They also have data on sea lice resistance, and they are also collecting data on PED, and AGD. The big breakthrough
– and the company’s big- gest success story to date – was in identifying a major gene affecting resistance to IPN. ‘The research was
part of work we did with the Roslin Institute and the universities of Stirling and Glasgow,’ Tinch explains. ‘The discovery of the IPN QTL was completely unexpected – a single gene that is almost almost vaccine-like in its ability to control disease resistance. We are two- thirds of the way through breeding IPN resistance into our broodstock.’ IPN is unique, however, and it is certainly unlikely that a single gene will be so effective against the other ‘three-letter diseases’. In the case of sea lice resist- ance, the geneticists at Landcatch, in collaboration with other researchers, have identified a handful
of major genes, and many more with minor effects. ‘What we have to do there,’ says Tinch, ‘is to look at all of the gene effects for each fish and come up with an individual value for each fish based on those geno- types. And this is what we expect for other diseases.’ However, this sort of
work cannot be under- taken using conventional genetics, but rather genom- ics. ‘By measuring disease resistance at a genomic level, we can go in and look at the patterns of markers that we see for individuals of high survivability and low survivability and check our broodstock population for fish with the same char-
www.fishfarmer-magazine.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68