Genotype-environment interactions for growth and survival of channel catfish (Ictalurus punctatus), blue catfish (Ictalurus furcatus), and channel catfish, I. punctatus, ♀×blue catfish, I. furcatus, ♂ hybrid fry at varying levels of sodium chloride

Sublethal effects of salinity and temperature on non-native blue catfish: Implications for establishment in Atlantic slope drainages

“…The optimal salinity for juvenile blue catfish appears to be around 4 psu as indicated by fastest growth and good body condition despite relatively low mean consumption rates. These results support a previous study on larval blue catfish which reported the highest survival and growth at 3 psu [15] and other studies of freshwater species (e.g., freshwater snakehead Channa punctata 5 psu [44], and Asian swamp eel 3 psu [26]). This may be because the osmotic gradient is lower at these salinities, and hence smaller amounts of energy are spent on osmoregulation, leaving a larger fraction of energy for growth [21,41].…”

“…The long-term effects of increased salinity on blue catfish biology, however, are not clear. Abass et al [15] reported maximum survival and growth of hatchery-spawned larval blue catfish at sodium chloride concentrations of 3 ppt (parts per thousand), but 100% mortalities at salinities �6 ppt. These results, though useful as a general indication of the salinity tolerance of blue catfish, may not be readily applicable to wild fish [16].…”

Comparison of growth performance among channel-blue hybrid catfish, ccGH transgenic channel catfish, and channel catfish in a tank culture system

“…Individual heterosis (dominance effects) had a strong positive effect on growth rates for channel catfish female, Ictalurus punctatus , × blue catfish, I. furcatus , male hybrid catfish 15 . Previous research has also shown higher growth rate for hybrid catfish than channel catfish 19 . However, Dunham et al 12 found that the channel catfish had more rapid growth than hybrid catfish in cages, but slower than hybrid catfish in ponds ( P < 0.01) and Small 48 demonstrated that growth of hybrid catfish is lower than channel catfish when they are reared in small tank/aquaria systems.…”

“…The F 1 hybrid catfish grew15–20% faster than the channel catfish 11 , 15 . Weight gain for KR channel catfish ♀ × D&B blue catfish ♂ hybrid catfish was bet ter, 94% he t eros is, than KR channel catfish in tank systems at 0 ppt sodium chloride 19 .…”

“…The hybrid resulting from the mating of channel catfish, Ictalurus punctatus , ♀ × blue catfish, I. furcatus , ♂ is superior to channel catfish because of its faster growth, better feed conversion, tolerance of low oxygen, increased resistance to many diseases, tolerance to harvest by seining, higher dress out and fillet yields 10 – 17 . However, The hybrid had negative heterosis for survival under sub-zero temperature 18 and salinity 19 . The channel catfish ♀ × blue catfish ♂ hybrid grows faster than the reciprocal hybrid (blue catfish ♀ × channel catfish ♂) 20 .…”