The Effects of Hypoxia on Certain Blood and Tissue Electrolytes of Channel Catfish, Ictalurus punctatus (Rafinesque)

Abstract

Channel catfish, Ictalurus punctatus (Rafinesque) exhibited changes in levels of muscle and blood electrolytes during recovery from short-term hypoxia. Ten minutes of confinement in water having zero rag/liter oxygen resulted in an acidosis characterized after 1 hr of recovery by elevated blood lactate, decreased blood pH, and an increase in plasma osmolarity and hematocrit. Muscle water content was increased at this time. Later changes in these parameters appeared to be influenced by season or temperature. Plasma osmolarity dropped below control levels in June and remained depressed after 36 hr of recovery. In August plasma osmolarity fluctuated at levels above control values and had not returned to normal after 48 hr. These data indicate that electrolyte imbalance persists for many hours after blood lactate has declined to control levels and this imbalance may limit the fish's ability to tolerate further stress. 593 TRANS. AMER. FISH. SOC., 1974, NO. 3

Hematology and agglutination titer after polyvalent immunization and subsequent challenge with Aeromonas hydrophila in Nile tilapia (Oreochromis niloticus)

“…A decrease in the number of erythrocyte and hematocrit percentage suggests that erythrocyte has been destructed by leukocytic activity. On the other hand, increased hematocrit is a result of oxygen depletion (Kirk 1974). In the present study, the infection and/or vaccine did not cause alteration in hematocrit percentage.…”

Haematological effects of prolonged sublethal hypoxia on channel catfish*Ictalurus punctatus (Rafinesque)

“…significant deviation from control values. An increase in haematocrit has been reported as a result of oxygen deficiency (Holeton & Randall, 1967b;Wood & Johansen, 1972;Swift & Lloyd, 1974;Kirk, 1974). Elevated values have been attributed to redistribution of water from the general circulation to tissues (Black et aL, 1966), erythrocyte swelling (Albers, 1970;Soivio et al, 1974) and spleenic contraction (Black, 1955).…”

Plasma corticosteroid dynamics in channel catfish, Ictalurus punctatus (Rafinesque), during and after oxygen depletion

“…Investigations into the osmoregulatory consequences of hypoxia (Kirk, 1974;Tomasso, unpubl. data) demonstrated that plasma chloride concentrations in channel catfish fluctuated inconsistently after, but not during, hypoxia.…”