The use of trilene- as anesthesia and triquilizer for catfish Clarias gariepinus juveniles

Abstract

The culture of the African catfish Clarias gariepinus is developing fast that more easier way of handling bigger fish is required both in the transportation and hypophysation/breeding. Such inputs like tranquilizer/anesthesia would help to reduce handling stress thereby reduce injury and death after operation. Trilene –Trichloroethylene is not common in the anesthesia of catfish; in this experiment four dosage levels were used to determine the suitable dosage and tolerance of this fish. Clarias gariepinus juveniles of weight range of 24 – 68 g and average weight of 41.0 g, standard length range of 140 - 215mm and total length range of150 - 238mm were weighed after 24hours of starving. Ten samples were randomly stocked in two Perspex tank of 70 x 50 x 60 cm and replicated. Anesthesia [Trilene –Trichloroethylene] was administered at 0.05, 0.1, 0.2 and 0.3 ml/litres; giving dilution of 1: 20,000; 1: 10,000; 1: 5,000 and 1: 3,333 respectively and were observed for 10-130 seconds. Room and water temperatures were 28oC and 27oC respectively during the period of the experiment. The behaviourial changes observed started from un-usual calmness, stress, highly stressed (swirling), loss of stability and jumping out attempt to being motionless and death. The anesthetized fish was culled out and transferred to prepared recovery tanks with non-anesthetic water. There was no attempt to physically transport fish but the un-usual calmness, observed shows that hatchery managers can use it for juveniles' transportation and during operation at spawning of catfish broodstock Further work is also required to ascertain effectiveness of its usage since Trilene has shorter analgesia time and longer recovery time.

Keywords: Trilene, Anesthetics, stress, sedation, dosage and recovery time.

Nigerian Journal of Fisheries Vol. 5 (1) 2008: pp. 1-8