Acoustic telemetry has become a common tool for observing migratory patterns and estimating species survival. As new telemetry technologies become available, studies of their effects on species of interest are imperative as is the development of implantation techniques. Over the past three years, researchers and engineers modified current acoustic micro-transmitters into less invasive designs by developing an injectable acoustic micro-transmitter (IAMT) for the Juvenile Salmon Acoustic Telemetry System (JSATS). Based on regional passive integrative transponder (PIT) tag implantation expertise, a capsule that can be injected with a needle and syringe is the least traumatic and cost effective method for implantation of IAMT in juvenile salmon. This presentation focuses on the effects of changing the injection angle and the rotation of the bevel throughout the injection process to isolate the effects of these two variables on wound size and healing time. Although the injection sites were not closed after injection (e.g., with sutures or glue), there were no mortalities, dropped tags, or indications of fungus, ulceration, and/or redness around the wound. Wound healing occurred within 7 days. Axial rotation and positioning during the injection process changed the resultant wound size and healing time.
Bevel Rotation and Insertion Angle: Decreasing Surgical Impacts On Salmonids
1. Bevel Rotation and Insertion
Angle: Decreasing Surgical
Impacts on Salmonids
SHON A. ZIMMERMAN, RHONDA K. KARLS, ERIC S. FISCHER,
BISHES RAYAMAJHI, AND CHRISTA M. WOODLEY
PRESENTED BY MARK WEILAND*
1
Pacific Northwest National Laboratory
AFS 2013
3. Background: Surgical Approach
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Current technique for biotelemetry and survival
studies in the basin is surgical implantation into the
coelomic cavity
Extensive handling
Induction Stage 4 anesthesia
Requires incisions 5-7 mm
Insertion of 2 tags
JSATS acoustic transmitters (AT)
Passive integrate transponders (PIT)
Requires 2 sutures
Overall time per fish: 4.5 - 10 min
Invasive “surgical” technique
5. Criteria for downsized, injectable JSATS acoustic
transmitters
Reduce:
handling and anesthesia exposure
implantation trauma (externally and internally)
wound extent and healing time
Maintain high tag retention
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Background: Surgical Approach
6. Objectives
6
Develop implantation procedure to MINIMIZE
Implantation time
Bio-effects
Healing time
Maintaining high AMT/PIT retention
Provide guidance to the JSATS injectable design
Size range of AMT
AMT meets biological objectives
Zimmerman et al. 2013
7. Implantation: PIT Injections
7
Intra-coelomic injections
Injection site
No sutures
Reduced
Handling and anesthetic exposure
Risk of tag loss
Risk of infection
Healing time
Implantation time
Reduced risk to fish and projects
Zimmerman et al. 2013
8. Implantation: PIT Design
PIT Design
Established Protocols
http://www.ptagis.org more specific to salmon and
Columbia Basin
8
PIT
Length
(mm)
PIT Weight
(±0.005 g)
PIT Outer
Diameter
(mm)
Needle
Gauge
(GA)
8.4 0.33 1.4 14
9-12.5 0.08-0.1 2.1 12
22-32 0.6-0.8 3.65 6
Zimmerman et al. 2013
9. Implantation: Needle Gauges
Needle
Gauge
Outer Diameter
(mm)
Inner Diameter
(mm)
JSATS AT
Diameter (mm)
12 2.77 2.16 2.08
9 3.75 2.99 2.91
8 4.19 3.42 3.40
9
8 GA
12 GA
Photo By M Halvorsen
Fish AT Limitations
PIT OD
3.6 mm
6 GA: 5.16 mm OD, 4.39 mm ID
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10. Needle Assessments
Metrics assessed for acceptance were:
Survival: Day 0-14 or -28
Tag retention: Day 0-14 or -28
Implantation time: Day 0
Wound healing: Day 0, 7, 14, 21, 28
Above metrics :
Assessed within and between experiments
Ranked by a performance index
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11. Implantation Techniques: Rotational Cut
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0-degree Rotation 90-degree Rotation 180-degree Rotation
Zimmerman et al. 2013
- 8 GA for injection of proposed AT designs
- 12 GA for injection of PIT (BioMark TX1411SST-1)
12. Results: Rotational Cut
12
- Tags drop
- Tended to slide down shaft premature
0-degree rotation 90-degree rotation 180-degree rotation
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13. Day 0 Day 7 Day 14
WoundExtent(mm2)
0.0
1.0
2.0
3.0
4.0
5.0
6.0
90-degree
180-degree
Results: Rotational Cut
Bryson, A.J., et al., Comparison of 180-degree and 90-degree needle rotation to reduce wound size in PIT-injected
juvenile Chinook salmon. Fish. Res. (2013) http://dx.doi.org/10.1016/j.fishres.2013.02.011
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14. Implantation Techniques: Rotational Cut
Factors to consider:
Axial force to penetrate skin
Peak force to cut through tissue
Target tissues depth and consistency
Force related to target tissue
Scales, thickness, etc.
Force related to target tissue location
Coelomic cavity, axial muscular, etc.
Observations:
Variable wound shapes
Wound shapes prevalent with surgeon
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15. Implantation Techniques: Rotational Angles
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Were wounds attributable to surgeon technique?
Variable wound shapes
Literature attributed to needle dullness (12 GA)
Angles of needle during injection phases:
Angle of insertion
Angle of rotation
Angle of injection
Angle of extraction
19. Or this graph your choice
19Days
0 14 21 28
WoundExtent(cmsq)
0.02
0.03
0.04
0.05
0.06
0.07
0.08
1-Stage
4-Stages
20. Summary
Survival
100% within and among experiments
Tag Retention
100% within and among experiments
Implantation Time
1 tag is faster to load/implant than 2 tags
Smaller needles easier to handle and implant
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21. Summary
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Wound extent
Injection technique can result in variable wounds
extents
90 degree rotation results in smaller wound extent until
Day 7
Using a 3-4 stage approach resulted in smaller wound
extent until Day 14
22. Relevance to Telemetry
No indications
AT or PIT moving out of injection point using 8, 9, or 12 GA
External infections of 8, 9, or 12 GA injection sites
Latent or delayed mortality from AT designs
Reduced
Anesthetic exposure
Surgical times by min 50%
Overall time
Increased efficacy
Fish health
Implantation and handling time
Costs
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23. Next Steps…
Current Testing
Rapid decompression exposure
Tag burden
Acoustic signal detection within fish
In-river survival
Technique Development
Surgeon training
Maintenance of needle sharpness
Handling dual tags
Sterilization
AT activation and tag assignment
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