Alison Ogilvie (Bachelor of Animal Science) Cristina Gordon - - PowerPoint PPT Presentation

Alison Ogilvie (Bachelor of Animal Science) Cristina Gordon (Bachelor of Chemical Engineering) Karthiga Kumanan (Bachelor of Biotechnology) Lito Molo (Bachelor of Fisheries)

WHY NEEDED??

• Identify stressors rapidly

in culture environment

• Provision of evidence of

freedom from pathogen

• Identify the cause/origin
• f disease outbreak

WHERE NEEDED ??

• Brood-stock facility
• Hatchery
• Grow-out

To understand the source of contamination in case of disease

• utbreak – Cross contamination

between departments Select pathogen free / minimal brood- stock for spawning To produce Vibrio-free algae Reduce bacterial load in Post-Larvae To ensure frozen feeds are free from pathogens : Squid, Polychaetes Minimise pathogen movement from hatchery to farm Ensure Larvae quality pass the farm quality standard.

Hatchery

Method Assessment Area Water source Microalgae unit Larval rear unit Artemia hatching unit Spawing room Maturation room Brood-stock ponds Brood-stock Frozen feeds Brood-stock Post larvae Frozen feeds Deformities Rostral Spine/ Shrimp Appendages Necrosis Fungal infection Fouling Muscle gut ratio Gut content and movement Size variation Post larvae Microscopic observation Laboratory Analysis In Hatchery WSSV PMMS Vibrio species Bacteriology PCR

Grow-out

• Pre-stocking

analysis

• Active-surveillance
• Post-harvest

analysis/Pond preparation

• Measure the toxic

metabolites in culture environment

• Total ammonia nitrogen
• Nitrite nitrogen
• Maintain high alkalinity

for a stable pH

• Phosphates, silicates and

Calcium-Hardness

Water Chemistry

Pond bottom soil analysis

• Soil analysis at multiple sampling

locations within each pond

• Organic matter analysis
• % of organic matter present in

pond soil

• Lowest % of organic load is

preferred

• Soil pH – pH 7
• Apparatus & reagents are

inexpensive and easy to purchase

• Simple & no professional training

required

Algal assessment

• Benefits of phytoplankton bloom
• Primary productivity for newly stocked PL
• Prevent benthic bloom
• Assimilate toxic metabolites & regulate DO
• Understand which family of

phytoplankton dominates the culture environment

• Diatoms/Dinoflagellates/Cyanobacteria
• Routine algal assessment
• Prevent over blooming of unwanted phytoplankton
• Cell count in case of HAB
• To understand the severity of HAB
• To assess the effectiveness of treatment

Bacteriology

• Vibrio is common aquaculture related
• pportunistic bacterial pathogen
• Quantify the potential pathogenic Vibrio in

culture environment

• V. parahaemolyticus .........Colonies with

blue to green centers.

• V. harveyi / V. fischeri........Greyish-green to

bluish-green colonies.

• Luminous Vibrio are potential disease

causing g agent.

Just visual inspection isn’t enough !!

PCR

• Expensive??? NO
• Rapid diagnosis of infectious

disease

• Quick turn-around time
• Highly sensitive, able to identify the

problem at an early stage

• Important tool for surveillance in

farm as well us water source

• Minimise risk of disease spread by

providing rapid result

• Can be performed by any technician

in a simple laboratory environment

Additional benefits of having an on-site laboratory

• Cost benefit
• avoids unnecessary treatment options
• prevent major loss by mitigating the risk at an earlier stage
• can be a tool for a better feed management to achieve lower FCR
• improves hatchery/grow-out performance by achieving a better survival,

growth rate & crop yield

• Environmental benefit
• able to quarantine the pond on time
• allows to control disease outbreak from affecting neighbouring farms

1) Identify the risk factor at earlier stage

2) Evaluate the whole batch 3) Control / mitigate

Act proactively, not reactively

Contact Us

Seafarms Group Limited

Level 11, 225 St Georges Terrace Perth WA 6000 PO Box 7312 Cloisters Square WA 6850

• T. +61 8 9321 4111
• F. +61 8 9321 4411
• E. info@seafarms.com.au