Effect of meal size on postprandial metabolic response in southern catfish (Silurus meridionalis).
Effect of relative meal size (0.6-24%) on specific dynamic action (SDA) was assessed in southern catfish juveniles (48.2+/-3.2 g) at 27.5 degrees C. Cutlets of freshly killed loach species were used as test diet. Energy expended during SDA was linearly correlated with relative meal size (r=0.949, p<0.001, N=47). There was no significant difference in SDA coefficient (energy expended on SDA quantified as a percentage of the energy content of the meal) among different relative meal size groups. Factorial metabolic scope increased from 1.47 to 4.08 when the relative meal size increased from 0.6% to 24%. The peak V O2 increased with meal size, but levelled when relative meal size gradually increased to the maximum. SDA duration showed a S-type (slow-fast-slow) increase course with increased meal size. The results of this study suggest that the high postprandial factorial metabolic scope and a trapezoid SDA curve might be the adaptation strategy of warm water sit-and-wait fish under the natural selection of evolution related to long-term food resources.
Fu
S J
SJ
College of Life Sciences, Chongqing Normal University, Chongqing, 400047, China. shijianfu9@hotmail.com
Xie
X J
XJ
Cao
Z D
ZD
D000821:Animal Feed; D000818:Animals; D001835:Body Weight; D002397:Catfishes / Q000378:metabolism*; D004032:Diet; D005247:Feeding Behavior; D008660:Metabolism / Q000502:physiology*; D019518:Postprandial Period / Q000502:physiology*