Effect of starvation on oxygen consumption and some blood parameters of the common carp (Cyprinus carpio L.)

Abstract

The experiment was conducted using 48 fish, common carp Cyprinus carpio L. (average weight 41.51±3.51 g). Fish were distributed on 6 aquaria each one represents a starvation period and contained 8 individuals. After two weeks of acclimatization on commercial diet to reduce individual differences in nutritional status, fish were exposed to starvation periods (2, 4, 6, 8, and 10 weeks). Fish weighed every two weeks with the sample of 5 fish for measurements of some blood parameters (Haematocrit PCV, haemoglobin Hb, total number of erythrocytes and leukocytes count, total protein, plasma glucose level) and the rate of oxygen and energy consumption. Body weight rates decreased gradually as a direct result of the starvation process. All the studied parameters except for plasma glucose level decreased significantly (P ≤ 0.01) after six weeks of starvation, and the decrease continued to the end of experiment which lasted for ten weeks.

Fasting and its implications for fish welfare in Atlantic salmon aquaculture

“…Prolonged fasting does not appear to cause a state of chronic stress in Atlantic salmon of ≈250 g at 12°C as inferred from haematological parameters, as resting blood plasma levels of cortisol, lactate, major ions, osmolality as well as the haematocrit and haemoglobin concentration were unaffected over a 4‐week fasting period 137 . In some fish species, fasting also did not affect haematological parameters, 141,142 while others may become progressively anaemic 143 . If Atlantic salmon were subjected to more extreme fasting periods than presently documented, haematological parameters would presumably change eventually to reflect an altered homeostasis.…”

“…137 In some fish species, fasting also did not affect haematological parameters, 141,142 while others may become progressively anaemic. 143 If Atlantic salmon were subjected to more extreme fasting periods than presently documented, haematological parameters would presumably change eventually to reflect an altered homeostasis. This could involve lower haematocrits, and elevated plasma cortisol and osmolality to reflect anaemia, chronic stress, and a less tightly regulated osmotic balance.…”