Rainbow trout (Oncorhynchus mykiss) resistance to columnaris disease is heritable and favorably correlated with bacterial cold water disease resistance1,2

Abstract

Columnaris disease (CD), caused by Flavobacterium columnare, is an emerging disease affecting rainbow trout aquaculture. Objectives of this study were to 1) estimate heritability of CD resistance in a rainbow trout line (ARS-Fp-R) previously selected 4 generations for improved bacterial cold water disease (BCWD) resistance; 2) estimate genetic correlations among CD resistance, BCWD resistance, and growth to market BW; and 3) compare CD resistance among the ARS-Fp-R, ARS-Fp-S (selected 1 generation for increased BCWD susceptibility), and ARS-Fp-C (selection control) lines. Heritability of CD resistance was estimated using data from a waterborne challenge of 44 full-sib ARS-Fp-R families produced using a paternal half-sib mating design, and genetic correlations were estimated using these data and 5 generations of BCWD resistance, 9-mo BW (approximately 0.5 kg), and 12-mo BW (approximately 1.0 kg) data from 405 ARS-Fp-R full-sib families. The CD and BCWD challenges were initiated at approximately 52 and 84 d posthatch, or approximately 650 and 1,050 degree days (°C × d), respectively. Survival of ARS-Fp-R families ranged from 0 to 48% following CD challenge and heritability estimates were similar between CD (0.17 ± 0.09) and BCWD (0.18 ± 0.03) resistance, and the genetic correlation between these 2 traits was favorable (0.35 ± 0.25). Genetic correlations were small and antagonistic (-0.15 ± 0.08 to -0.19 ± 0.24) between the 2 resistance traits and 9- and 12-mo BW. Two challenges were conducted in consecutive years to compare CD resistance among ARS-Fp-R, ARS-Fp-C, and ARS-Fp-S families. In the first challenge, ARS-Fp-R families (83% survival) had greater CD resistance than ARS-Fp-C (73.5%; P = 0.02) and ARS-Fp-S (68%; P < 0.001) families, which did not differ (P = 0.16). In the second challenge, using an approximately 2.5-fold greater challenge dose, ARS-Fp-R families exhibited greater CD resistance (56% survival) than ARS-Fp-S (38% survival; P = 0.02) families. The favorable genetic correlation between CD and BCWD resistance is supported by greater CD resistance of the ARS-Fp-R line compared to the ARS-Fp-C and ARS-Fp-S lines and suggests that both traits will be improved simultaneously when selection is practiced on only 1 trait. In summary, these data indicate the feasibility of further selective breeding of the BCWD-resistant ARS-Fp-R line for increased CD resistance to produce a double pathogen-resistant line of rainbow trout.

Breeding for improved resistance to Edwardsiella ictaluri in striped catfish (Pangasianodon hypophthalmus): Quantitative genetic parameters

“…Furthermore, the reported genetic correlations of disease resistance with body weights were not conclusive in the literature, either positive (e.g., mean value of 0.25 from eight studies in fish and shrimp (Gjedrem & Baranski, 2010)) or negative (e.g., −0.64 to −0.55 between growth and resistance to white spot syndrome virus in Whiteleg shrimp, −0.33 to −0.01 between growth and viral haemorrhagic septicaemia in rainbow trout (Gitterle et al, 2005;Henryon et al, 2002) or −0.5 in coho salmon (Yáñez et al, 2016)). There were also reports of close to zero or non-significant genetic correlations between growth and diseases traits in salmonids (Evenhuis, Leeds, Marancik, Lapatra, & Wiens, 2015;Silverstein et al, 2009) or in European seabass (Doan et al, 2017). In Whiteleg shrimp, heritability estimated for Taura syndrome virus (TSV) was 0.28-0.30, but selection for improved TVS reduced growth rate by 4.6% after one generation of selection (Argue, Arce, Lotz, & Moss, 2002).…”

Resistance to Streptococcus iniae and its genetic associations with traits of economic importance in Asian seabass (Lates calcarifer)

“…Our result is consistent with a meta‐analysis of 26 studies involving 12 aquaculture species (mean r g = 0.13, 95% CI: −0.07 to 0.33, p > .05; Nguyen, unpublished). Examples are in Atlantic salmon with the positive genetic correlation estimates between columnaris disease and body weight, r g = 0.35, in rainbow trout (Evenhuis et al, ), or the negative genetic correlations between viral haemorrhagic septicaemia and growth in rainbow trout (Drangsholt et al, ; Henryon et al, ) or between Piscirickettsia salmonis and growth in coho salmon (Yáñez et al, ). A majority of the literature estimates of the genetic correlations between disease resistance and growth was low and not significant (Bangera, Ødegård, Præbel, Mortensen, & Nielsen, ; Phuthaworn, Nguyen, Quinn, & Knibb, ; Silverstein et al, ).…”

“…Our result is consistent with a meta-analysis of 26 studies involving 12 aquaculture species (mean r g = 0.13, 95% CI: −0.07 to 0.33, p > .05 ; Nguyen, unpublished). Examples are in Atlantic salmon with the positive genetic correlation estimates between columnaris disease and body weight, r g = 0.35, in rainbow trout (Evenhuis et al, 2015), or the negative genetic correlations between viral haemorrhagic septicaemia and growth in rainbow trout (Drangsholt et al, 2012;Henryon et al, 2002) or between…”

“…Improved resistance to infectious diseases through selective breeding has been demonstrated in previous studies (Doan et al, ; Trang, Nguyen, Nguyen, Wayne, & Nguyen, ). Across aquaculture species, heritabilities (h 2 ) for resistance to a range of diseases from parasites to bacteria and virus are low to moderate (Ødegård, Baranski, Gjerde, & Gjedrem, ), for instance, h 2 = 0.03 – 0.18 for resistance to Aeromonas salmonicida bacteria in Atlantic salmon ( Salmo salar ) (Gjerde, Evensen, Bentsen, & Storset, ; Kjøglum, Henryon, Aasmundstad, & Korsgaard, ; Ødegård, Olesen, Gjerde, & Klemetsdal, , ; Olesen, Hung, & Ødegård, ); h 2 = 0.05–0.25 for resistance to Yersinia ruckeri and Flavobacterium psychrophilum bacteria in rainbow trout ( Oncorhynchus mykiss ) (Evenhuis, Leeds, Marancik, Lapatra, & Wiens, ; Hastefnl, Guo'ding, & Eve‐Risen, ; Leeds et al, ; Silverstein et al, ; Wiens et al, ); h 2 = 0.03 and 0.04 for resistance to Aeromonas hydrophila bacteria in Rohu carp ( Labeo rohita ) (Mahapatra et al, ) and in common carp ( Cyprinus carpio ) (Ødegård et al, ), respectively; or h 2 = 0.08 for resistance to Vibrio anguillarum in Atlantic cod (Kettunen, Serenius, & Fjalestad, ). There are also reports of moderate heritability for disease resistance in salmon or rainbow trout (Yáñez, Houston, & Newman, ).…”

Draft Genome Sequence of the Fish Pathogen Flavobacterium columnare Strain CSF-298-10

“…The CSF-298-10 strain is a genomovar I strain that was isolated in 2010 from the gill tissue of a diseased rainbow trout (4) in the Snake River valley of Idaho, USA. This strain is currently being used to initiate a breeding program to improve innate survivability against columnaris disease (9). …”