Study On The Keep-alive Technology For Yellow Catfish

In this study, the ecological ice and anesthesia was used to research thekeep-alive technology of yellow catfish, designed to explore and find out the relatedtechnical parameters for catfish transport, the most suitable conditions to determine thedifferent keep-alive technology to maximize the benefits of transport in differentenvironments and extend the transport time.This research examined the keep-alive transport technology without water ofyellow catfish in the ecological ice-temperature zone, the impact factors, and changes ofbiochemical indexes in fish muscle and blood. The result showed that ecologicalice-temperature zone of yellow catfish was-1~4℃, and the temperature, oxygensupply and temporary culture time were the main impact factors that affected thesurvival time of yellow catfish. After two days temporary culture, the yellow catfishcould survive for24hours with pure oxygen at2℃, and the catfish could successfullyrevive within about20min when put them into water at the ambient temperature; Lacticacid in muscle increased, whereas glycogen content and pH decreased during keep-aliveprocess, levels of creatinine, blood glucose, lactic acid in blood were significantlyincreased, no significant alternations were observed in the other biochemistryparameters before and after keep-alive experiment.General water bath was used to study the anesthetic effect of eugenol on yellowcatfish, the aim of this paper was to determinate the anesthetic effect and the changes inrespiratory frequency of different concentrations of eugenol on yellow catfish, the effectof anesthesia time on recovery time and the influence of water temperature on the effectof anesthesia time. The results showed that with the concentration of eugenol increasedfrom20mg/L to60mg/L, anesthesia time of yellow catfish gradually decreased from12.17±0.48min to1.83±0.19min and the recovery time from3.53±0.24mingradually increased to11.45±0.78min, there was significant difference in the anesthesiatime and recovery time among the different groups. The respiratory rate is an importantindicator to measure the degree of anesthesia, in general, the respiratory frequency of yellow catfish showed a trend towards decreasing. Under40mg/L eugenol conditions,the recovery time is prolonged with the increasing anesthesia time, with anesthesia timevaried from10min to70min, recovery time of yellow catfish gradually increased from3.93±0.30min to6.69±0.78min and within60min the recovery rate can reach100%,however the recovery rate decreased to90%at70min. Water temperature was animportant factor affecting the anesthesia time, the maximum time was4.19±0.38minat15℃and the minimum time was2.46±0.21min at30℃. The results indicatedthat eugenol was a safe and effective anesthetic that can be used for anesthesia ofyellow catfish.This research examined the keep-alive transport technology of yellow catfish, theimpact factors, and changes of indexes in fish muscle and blood during the keep aliveprocess. The result showed that after two days temporary culture, the yellow catfishcould survive for36hours under the conditions of40mg/L eugenol anesthesia withpure oxygen at5℃, and the catfish could successfully revive within about15minwhen put them into water at the ambient temperature; Muscle glycogen contentdecreased, the lactic acid content increased, muscle pH decreased during the keep aliveprocess; blood creatinine, glucose, lactic acid, uric acid content significant increased inthe process of keep-alive, albumin showed a significant decline, total protein decreasedand then returned to normal levels, no significant alternations were observed in the ureacontent.This research examined the keep-alive transport technology of yellow catfish, theimpact factors, and changes of indexes in fish muscle, blood and water. The resultshowed that after two days temporary culture, the yellow catfish could survive for102hours under the conditions of fish to water ratio of1:1with pure oxygen at5℃, andthe catfish could successfully revive within about10min when put them into water atthe ambient temperature; muscle glycogen content decreased, the lactic acid contentincreased, muscle pH decreased during the keep alive process; dissolved oxygendecreased, ammonia content increased, pH basically unchanged in water； bloodcreatinine, glucose, lactic acid, uric acid content significant increased in the process ofkeep-alive, albumin showed a significant decline, total protein decreased and thenreturned to normal levels, no significant alternations were observed in the urea content.