Slaughter is generally a two-stage process:

Immersion time: set a timer to ensure all shrimp are effectively killed using the timings worked out.

Monitoring and verification: periodically check the temperature of the slurry bath to ensure it remains at ≤4°C. Add more ice if necessary to maintain the temperature. Check for indicators of death according to Indicator 4.4.5.

After the set time, remove a few shrimp and check for the absence of movements; the shrimp should also exhibit body rigidity, indicative of effective killing.

The use of body movement as an indicator for the effectiveness of stunning or killing can be misleading as muscular spasms regularly occur in unconscious or dead shrimp. Studies on crustaceans, including shrimp, indicate that they can exhibit reflex actions and movements even when they are unconscious or brain dead. This is because such movements are often dominated by nerve circuits in the peripheral nervous system rather than the brain. Body movements indicating walking leg movements and coordinated swimming movements are relevant movements to watch out for, and that may indicate consciousness

Killing effectiveness in the UoC should be assessed by confirming signs of unconsciousness:

If there is uncertainty about whether a crustacean is unconscious:

Employees should demonstrate knowledge of the approved slaughter methods and monitoring.

Records:

Monitoring of stunning and slaughter in conformance to the requirements.

Records, employee interviews and observations of stunning and slaughter operations during the audit should demonstrate the implementation of the requirements, and that there is an available backup method or knowledge of corrective measures to be carried out.

Weineck, K., Ray, A.J., Fleckenstein, L.J., Medley, M., Dzubuk, N., Piana, E., & Cooper, R.L. (2018) Physiological Changes as a Measure of Crustacean Welfare under Different Standardized Stunning Techniques: Cooling and Electroshock Animals.

CIWF (2020) Tesco and Hilton Seafood — Improving the welfare of whiteleg shrimp (Pennaus vannamei) at harvest. CIWF Report 7pp.

Conte, F.; Voslarova, E.; Vecerek, V.; Elwood, R.W.; Coluccio, P.; Pugliese, M.; Passantino, A. (2021) Humane Slaughter of Edible Decapod Crustaceans. Animals.

Barrento, S., Pedrazzani, A., Ostrensky, A., & Quintiliano, M. (2023). Shrimp Welfare Indicators [Online course]. In S. Barrento, M. Quintiliano, & J. Muirhead (Eds.), FAI Academy. https://fai.academy/

For developing a site-specific predator control within the HMP, the UoC should consider:

The site-specific characteristics required to be assessed by Indicator 4.2.1.8.e) predator control measures specific to the type of handling, e.g.:

Predator control measures specific to the type of handling operations.

Verification of mortalities associated with predators during handling operations.

The HMP includes the required considerations above.

Employees are:

Trained on predator control verifications, e.g.:

For developing a site-specific biosecurity mechanism within the HMP, the UoC should consider:

Biosecurity measures related to the type of handling, e.g.:

For developing a site-specific biosecurity during handling the HMP includes the considerations for:

The HMP includes the required minimum considerations above.

Employees are:

Lightner, D.V. (2007), Biosecurity in Shrimp Farming: Pathogen Exclusion through Use of SPF Stock and Routine Surveillance. Journal of the World Aquaculture Society.

Visual inspection after handling should be included in the HMP.

The monitoring process, that incorporates the corrective actions required, included in the HMP.

Records that confirm the monitoring of the morphology and behaviour at the feeding trays. A checked box on the monitoring records indicating whether monitoring morphology and behaviour took place or not is accepted.

Employees should demonstrate awareness of the established behavioural monitoring process.

The monitoring process included in the HMP that incorporates corrective actions and is implemented.

Implementation can be verified by cross-checking the process with relevant records, information from employee interviews and observations.

Acclimatisation measures should be designed and maintained, e.g.:

acclimatisation measures and monitoring of the water quality according to HMP.

Records that confirm the monitoring of acclimatisation parameters before stocking.

Employees should demonstrate awareness of the acclimatisation measures and monitoring process above.

The acclimatisation measures included in the HMP incorporate the minimum required elements and are implemented.

Implementation can be verified by cross-checking the process with relevant records, information from employee interviews and observations.

Draining the pond completely helps in eliminating unwanted organisms and disease.

Areas that cannot be completely drained should be treated with disinfectants to kill any pathogens, e.g.:

Removing any dead or living animals helps in preventing disease spread and decay, which can affect the water quality and the health of future pond crops, e.g.:

Remove any organic debris such as leaves, branches and sludge. If the pond water is too acidic, agricultural lime (calcium carbonate) may be added to neutralise the pH, making the environment more suitable for crustacean e.g.:

Records confirming the monitoring of the required parameters for pond preparation and their conformance with acceptable quality levels included in the HMP prior to stocking.

Record of drying period.

Record of addition of lime if applied.

The water quality monitoring process, that incorporates the minimum elements required for pond preparation.

Employees should demonstrate awareness of the established water quality monitoring process during handling.

Pond preparation process, that incorporates the minimum elements required, included in the indicator and cross-checking with the handling operations present in the HMP.

Implementation can be verified by cross-checking the process with records, information from employee interviews and observations.

The Fish Site (2016) Management of intensive Vannamei shrimp ponds. Article.

Examples of considerations of external conditions:

Avoid transferring post-larvae during periods where there are less than favourable conditions:

HMP includes consideration for external conditions necessary to perform handling.

Records:

HMP includes considerations for external conditions for handling and are implemented.

Implementation can be confirmed by cross-checking the HMP with records, information from employee interviews and observations.

The contingency plans should consider:

Effective corrective measures, e.g.:

HMP includes processes’ contingency plans.

Records:

The HMP includes considerations on crustacean health and welfare before handling events, including considerations for the existence of a backup system.

Presence of a backup system.

Employees are:

Records: