Variations in growth in haemoglobin genotypes of Atlantic cod

Abstract

In the present paper are described the growth properties of three different haemoglobin genotypes of juvenile Atlantic cod (Gadus morhua) reared at 7, 10, 13 and 16°C. In addition one group was reared under ''temperature steps'' i.e. moved successively from 16 to 13 and 10°C. The genotype Hb-I(2/2) displayed the overall highest growth rate in the temperature range 13-16°C, whereas the Hb-I(1/1) genotype showed the highest overall growth at the lowest temperature (7°C). Accordingly, we found a significant interaction between genotype and temperature. The differences in growth were largest when cod were reared under the temperature step regime where the Hb-I(2/2) genotype displayed 17 and 24% higher growth than Hb

High-resolution melting analysis of common and recombinant genotypes of the Atlantic cod (Gadus morhua) hemoglobin β1 gene in transatlantic populations

“…The two substitutions seem to be responsible for the higher oxygen-binding affinity of the HbI-2 isoform at low temperatures than the less temperature-sensitive HbI-1 type (Karpov and Novikov 1980;Brix et al 2004;Andersen et al 2009). Significant differences between HbI-1/1 and HbI-2/2 homozygotes have also been found in terms of temperature preference (Petersen and Steffensen 2003), competitive feeding strategy (Salvanes and Hart 2000), age of maturation (Mork et al 1983), muscle cellularity (Johnston et al 2006), and growth rate (Naevdal et al 1992;Imsland et al 2004), although some conflicting results exist. Despite strong linkage disequilibrium between the closely positioned M/V and K/A replacements, rare recombinants of the cod Hb-b1 mutations were detected in Northeast Atlantic populations by single-nucleotide polymorphism (SNP) analysis (Andersen et al 2009).…”

Population variation in thermal growth responses of juvenile Atlantic cod (Gadus morhua L.)

“…Understanding the relationship between temperature and growth is complicated however, because growth rates may be influenced by a number of other factors including food consumption (Jobling 1985;Yoneda and Wright 2005), photoperiod (Kadri et al 1997), duration of feeding (Biswas and Takeuchi 2003) and time of year (Levesque et al 2005). Growth rate in cod has a relatively high heritability (Gjerde et al 2004) and several gene complexes are known to affect growth rates including haemoglobin genotype (Naevdal et al 1992;Imsland et al 2004) and pantophysin, a nuclear RFLP locus (Case et al 2006). Thus regional differences in growth rate, such as those reported for cod by Brander (1994), arise from a complex suite of intrinsic and extrinsic factors.…”

Integrating the markers Pan I and haemoglobin with the genetic linkage map of Atlantic cod (Gadus morhua)

“…Haemoglobin (Hb), pantophysin (Pan I), and microsatellite markers have been widely used to characterize the genetic diversity of Atlantic cod populations and their dispersal characteristics [2,3]. In addition, Hb analyses have revealed correlations between allele types and traits such as growth [2,4] , water temperature preference [5], age and seasonality of sexual maturation [6] or annual mortality [7]. Similarly, growth rate [8], water temperature, salinity and depth appear to have an effect on Pan I allele frequencies [2,9,10].…”