Aqui-S (Canada)

Company: Merck Animal Health

Isoeugenol Concentrate 50% w/w

Anesthetic

FOR VETERINARY USE ONLY

DIN 02540096

Description

AQUI-S^® is a stable, clear to yellow viscous oily liquid formulation which can be dispersed into fresh or saltwater as an immersion anesthetic for salmonids.

It contains 50% w/w isoeugenol as the active ingredient and 50% w/w polysorbate 80 as the excipient.

Aqui-S Indications

For sedation and anesthesia of salmonids.

Directions For Use

● Handle animals gently. Avoid stress prior to treatment.

● Determine the isoeugenol concentration required for the application.

● Use:
• 2.5-5.0 mg/L isoeugenol (equivalent to 5-10 mg/L AQUI-S^®) for sedation (uncoordinated swimming movements but maintains equilibrium, loss of reaction to external stimuli), or
• 8.5-12.5 mg/L isoeugenol (equivalent to 17-25 mg/L AQUI-S^®) for anesthesia (loss of equilibrium, locomotion, and cough reflex in response to external stimuli, and depressed ventilation rate).

● Determine the volume of treatment water and calculate the required volume of AQUI-S^® (refer to Table 1 as a guide).

● Dilute AQUI-S^® with water at a ratio of 10 parts water to 1 part AQUI-S^® and vigorously mix to form a milky white emulsion (stock solution).

● Add all the AQUI-S^® stock solution to the treatment water and mix well to ensure uniform dispersion in the treatment water. Use the AQUI-S^® stock solution immediately following preparation.

● Expose fish to the AQUI-S^® treated water until desired sedative/ anesthetic effect is achieved.

● Aerate water with oxygen or air to maintain dissolved oxygen concentration.

● Temperature and pH of water should be similar to the values to which the animals have been acclimatized.

● For recovery: Place sedated/anesthetised animals in clean, well aerated water and monitor until coordinated swimming movements return.

Table 1: Volume of AQUI-S^® to add to treatment water to achieve a target concentration of isoeugenol.

To calculate AQUI-S^® volume (mL) from target isoeugenol concentration and volume of treatment water, use the following equation:

e.g. If target concentration is 5.0 mg/L isoeugenol, and treatment water volume is 10 m³: AQUI-S^® volume = (2*5.0*10)/1.09 = 92 mL.

To convert isoeugenol concentration to AQUI-S^® concentration, multiply the isoeugenol concentration by 2. AQUI-S^® is 50% w/w isoeugenol.

To convert AQUI-S^® volume to AQUI-S^® mass, multiply the volume by 1.09 (AQUI-S^® density). e.g. 92 mL * 1.09 = 100 g.

Contraindications

None.

CAUTIONS

Care should be taken not to overdose fish as death has been reported. Avoid unnecessary extended exposure.

WARNINGS

Treated salmonids must not be slaughtered for use in food for at least 6 degree-days after the latest treatment with this drug. To convert from degree-days to calendar days/hours, refer to Table 2.

Table 2: Conversion between 6 degree-days and calendar days/hours at various water temperatures.

Harmful if swallowed.

This product can cause skin and eye irritation and skin sensitisation.

It may have a localised anesthetic effect.

When handling the product, avoid oral exposure and direct contact with eyes or skin. Wear protective gloves.

Wash hands thoroughly with soap and water after handling.

If accidental eye or skin contact occurs, rinse thoroughly with water. If irritation occurs, seek medical attention.

KEEP OUT OF REACH OF CHILDREN.

ADVERSE REACTIONS

● Death has been reported with overdosing this product as well as administration to stressed fish.

● Lack of efficacy has been associated with underdosing this product.

● Underdosing may lead to stressed fish during handling which may result in death.

Under and overdosing may occur due to incorrect treatment volume calculation, inadequate mixing of the AQUI-S^® stock solution and/or inadequate mixing in the treatment water. See DIRECTIONS FOR USE for appropriate dosing and recovery instructions.

Overdose

In case of accidental overdose/over-exposure remove animals from treatment area and irrigate gills with clean, well aerated water until ventilation resumes.

ANIMAL SAFETY

A study was conducted to assess safety of AQUI-S^® when administered at concentrations of 1.4- (17 mg isoeugenol/L), 2.7- (34 mg/L), and 4.1- times (51 mg/L) the highest effective concentration of 12.5 mg isoeugenol/L for 3-times the exposure time required to obtain anesthesia. The study included 120 Atlantic salmon (30 controls, 90 treated) with a mean weight of 2.4 kg. A total of 11 mortalities were observed during the study. Four in the control group were accidental; two in the 1.4-times group were due to water quality. The five remaining mortalities (3 in 2.7-times group and 2 in 4.1-times group) were due to respiratory depression with no opercular movements and happened before the implementation of an assisted recovery procedure. This procedure consisted of improving water flow through the gills by moving the fish forward and backward into the water. Subsequently, only 2 fish in the 1.4-times group, and one in the 2.7-times group had to follow this procedure.

ANIMAL EFFICACY

Eighty-five 3-year-old Atlantic salmon were included in an efficacy study; 25 received a concentration of 8.5 mg isoeugenol/L, 30 received 12.5 mg/L and 30 received 17 mg/L. Efficacy was measured as exposure time to reach sedation, full anesthesia, and recovery after transfer to pure seawater. Sedation was defined as restraining fish by hand to the tank side for a period of 5 sec without struggling or resistance response; anesthesia as an absence of reflective cough within 5 sec of touching a gill arch in the air and in the water; recovery as response with the righting reflex of fish placed in lateral recumbency. An increase in concentration of AQUI-S^® resulted in a decrease in time to sedation and to anesthesia. Mean times to sedation were 4’47”, 3’55”, and 2’44” for the 8.5 mg/L, 12.5 mg/L and 17 mg/L groups, respectively. Mean times to anesthesia were 35’53”, 25’25”, and 16’43” for the three tested concentrations above, respectively. The effect of the concentration on time to recovery was not significant, with recovery times of 17’58”, 18’31”, and 21’52”, respectively.

An additional 30 2.5-year-old Atlantic salmon were exposed to a concentration of 5 mg isoeugenol/L. Mean time to sedation was 3’26” and mean time to recovery was 10’27”.

A multicenter field study assessed the sedation of Atlantic salmon during smolt transfer. A total of 719,896 smolts (average weight 65-98 g) received 2.5 mg isoeugenol/L while 556,671 smolts were controls. Effect was reached within 6 minutes after end of product administration. The fish were lightly sedated, with disoriented behaviour, swimming slowly and haphazardly, but maintaining equilibrium. The response to stimuli was reduced, but respiration remained normal. Fish could easily be caught by net or using bare hands. Fish showed no sign of excitation, or deeper levels of anesthesia.

STORAGE

Store at 15 °C - 30 °C.

Protect from direct sunlight.

DISPOSAL

● Dispose of used treatment solution by dilution in a large body of water.

● Do NOT dispose undiluted AQUI-S^® in the environment.

● Triple rinse container with water and dispose in a suitable landfill.

HOW SUPPLIED

Available in 1 L and 4 L HDPE containers.

MANUFACTURED BY

AQUI-S New Zealand Ltd., 6 Aglionby Street, Lower Hutt 5010, New Zealand

DISTRIBUTED BY

Intervet Canada Corp., Subsidiary of Merck & Co., Inc., 16750 route Transcanadienne, Kirkland, QC H9H 4M7, Canada

Phone: 1 866 683-7838

DATE OF APPROVAL July 31, 2023

LEAF007 R00

CPN: 1208336.0