Anaesthetic efficacy of eugenol on various size classes of angelfish (Pterophyllum scalare Schultze, 1823)

Abstract

Anaesthetic efficacy of eugenol was investigated on Pterophyllum scalare. A total of 130 fish with average weights of 1.0 ± 0.5, 5.0 ± 1.0 and 10.0 ± 1.0 g were subjected to 1.25, 2.5, 4.0, 5.5 and 7.0 mg/L eugenol, and behavioural responses were observed. Induction and recovery times were significantly affected by the interactive effect of eugenol concentration and fish weight (p < .05). Generally, 49.9–128 s after exposure to 1.25–7 mg/L eugenol, fish reached stage 3. Fish entered stage 4 over 55–135 s post exposure to such concentrations. Recovery time was 393.5–597.7 s in all sizes. Any increase in eugenol concentration led to a significant decrease in the induction time with a subsequent increment of the recovery time. Concentrations of eugenol and fish size along with their interactive effects have significantly contributed to the regression models, with concentration recording the highest beta values for stages 1, 2, 3 and 4 (−0.903, −0.898, −0.976 and −0.864 respectively) and the product of size and anaesthetic concentration for full recovery in smaller fish (0.647) and eugenol concentration in larger ones (0.967). Recovery time was fitted to induction time to stage 4 via quadratic and linear regression models in smaller and larger fish respectively. Results revealed the minimal eugenol concentration to induce anaesthesia in various size classes of angelfish in less than 3 min was 1.25 mg/L. Our results showed eugenol as an effective and safe anaesthetic; however, it is not advisable for live fish transportation.

Efficacy of Benzocaine, Eugenol, and Menthol as Anesthetics for Freshwater Angelfish

“…Mitjana et al (2014) concluded that eugenol at 100 mg/L is appropriate for Freshwater Angelfish (average body weight = 2.46 AE 0.60 g [mean AE SD]), which is similar to the results of this study. Tarkhani et al (2017) recommended a much lower eugenol concentration (5.5 mg/L) for Freshwater Angelfish, but their study fish were smaller (1-, 5-, and 10-g weight categories) than those used here. Millan-Ocampo et al (2012) and Chellapan et al (2013) reported intermediate effective eugenol concentrations (40 and 45 mg/L) for induction of Freshwater Angelfish that were of similar size to those used by Tarkhani et al (2017).…”

“…Tarkhani et al (2017) recommended a much lower eugenol concentration (5.5 mg/L) for Freshwater Angelfish, but their study fish were smaller (1-, 5-, and 10-g weight categories) than those used here. Millan-Ocampo et al (2012) and Chellapan et al (2013) reported intermediate effective eugenol concentrations (40 and 45 mg/L) for induction of Freshwater Angelfish that were of similar size to those used by Tarkhani et al (2017). The variation in the recommendations for eugenol may be due to the difference in fish species, fish size, anesthetic concentration, experimental design, or statistical analysis.…”

“…EFFICACY OF ANESTHETICS FOR FRESHWATER ANGELFISH specifications described by Marking and Meyer (1985). According to Millan-Ocampo et al (2012), Chellapan et al (2013), Mitjana et al (2014), and Tarkhani et al (2017), eugenol is an efficient anesthetic for Freshwater Angelfish. Mitjana et al (2014) concluded that eugenol at 100 mg/L is appropriate for Freshwater Angelfish (average body weight = 2.46 AE 0.60 g [mean AE SD]), which is similar to the results of this study.…”

Development of a colloidal gold immunoassay for the detection of four eugenol compounds in water

“…Among them, eugenol is widely used in the field of aquatic product transportation because of its high efficiency and low cost (Li, Zhang, & Liu, 2015). Several studies have demonstrated that eugenol is effective and safe as an anesthetic (Mi, Qian, & Mao, 2013;Tarkhani, Imani, Jamali, & Farsani, 2017). However, the safety of eugenol is still controversial, and it is reported to remain on the skin of fish and then remain in the human body through food circulation (Cowing, Powell, & Johnson, 2015).…”

Influence of temperature and size on menthol anaesthesia in Chinese grass shrimp Palaemonetes sinensis (Sollaud, 1911)

“…To date, the anaesthetic effects of menthol have been studied in only two crustaceans: Macrobrachium rosenbergii (Manush & Asimkumar, ) and M. tenellum (Palomera, Zaragoza, Galván & Vega‐Villasante, ). Although some research has shown that environmental factors such as water temperature and body size affect clove oil anaesthetic efficiency in fish, there have been no studies that have demonstrated any correlations between those factors and menthol anaesthetic efficacy, even in fish (Hoseini, Rajabiesterabadi & Tarkhani, ; Santos, Ghanawi & Saoud, ; Tarkhani, Imani, Jamali & Farsani, ). In addition, no information or assessments are available concerning weight change and survival rate after anaesthesia.…”