Abstract
Residual quantification of the anesthetics clove oil (CO) – isoeugenol (ISO), eugenol (EUG) and methyleugenol (MET) –,benzocaine (BZN) and tricaine (MS-222) was made in fillets of two fish species: Nile tilapia (Oreochromis niloticus) and acatfish hybrid, cachadia (Pseudoplatystoma reticulatum x Leiarius marmoratus). Samples (n=4) of each fish wereevaluated after submitted to anesthesia in five dosages defined based on the induction time of each species afterdepuration times (0h, 12h, 24h and 48h). Different methodologies of sample preparation were tested and selectedaccording to the better recovery. The quantification of anesthetics was performed by UPLC-DAD. The variance of residualmeans among anesthetics, dosages and fish species was compared. After anesthesia (0h) both species, tilapia andcachadia, presented residual anesthetics. Fishes depurated during 12h, 24h and 48h did not present detectable values, itmeans, values were below the limits of detection. BZN presented the highest mean residual concentration for tilapia andcachadia (p=0.01), while MS-222 presented the lowest residual amounts in tilapias and EUG in cachadias, what may berelated to the metabolism and carcass composition of each fish species. There were no significant differences among thefive dosages, except the lowest MS-222 concentration in tilapias that resulted in higher residual concentrations becauselow dosages increase the induction time and consequently the permanence of the fish in anesthesia. Ultimately, meanvalues of residues in cachadia were higher than in tilapia, and MS-222 and EUG presented the lowest residual values fortilapia and cachadia, respectively.
Highlights
IntroductionNowadays the most used anesthetics on aquaculture are MS-222, BZN, clove oil (CO) or formulations containing its active ingredient: ISO, menthol, quinaldine and metomidate (CCAC, 2011; Food and Drug Association (FDA), 2011; Kiessling et al, 2009)
On aquaculture the management, transport, marking, application of hormones and vaccines cause intense stress on animals, and in this context anesthetic or analgesic compounds have been applied trying to ease the negative effect of such practices (Mettam et al, 2011; Sneddon, 2009; Ross et al, 2008).Nowadays the most used anesthetics on aquaculture are MS-222, BZN, clove oil (CO) or formulations containing its active ingredient: ISO, menthol, quinaldine and metomidate (CCAC, 2011; Food and Drug Association (FDA), 2011; Kiessling et al, 2009)
Maceration resulted on a satisfactory performance in relation to the recovery of analyzed analytes (Table 2) on matrices applied to this work, besides it has decreased costs with reagents, equipment and time spent per analysis, since a total of 30 samples per day were processed comparing with 17 made by Meinertz et al (1999)
Summary
Nowadays the most used anesthetics on aquaculture are MS-222, BZN, CO or formulations containing its active ingredient: ISO, menthol, quinaldine and metomidate (CCAC, 2011; FDA, 2011; Kiessling et al, 2009) Such compounds may persist on the animal organism even after being metabolized, and it is necessary to define the adequate depuration period for each species and anesthetics applied, as well as the conditions for application, like concentration, time of permanence in anesthesia and recovery (Mettam et al, 2011; Sneddon, 2009). The anesthetic residual period depends on factors like temperature, salinity, chemical composition of water, fat content, among others (Burka et al, 1997) Such factors may contribute differently with fishes of temperate and tropical regions, for example, once these last are submitted to higher temperatures, what explains their faster metabolism. Other important aspect to be considered is the physiology of each species since there are more than 30000 fish species (Zahl et al, 2012)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
