Retention and Physiological Effects of Surgically Implanted Telemetry Transmitters in Blue Catfish

• Published in: North American journal of fisheries management 2012-04, Vol.32 (2), p.276-281
• Main Authors: Holbrook, S. Chad, Byars, William D, Lamprecht, Scott D, Leitner, Jean K
• Format: Article
• Language: English
• Subjects: abdominal cavity; adults; catfish; Ictalurus furcatus; integument; intestines; necropsy; stomach; surgery; telemetry
• ISSN: 1548-8675; 0275-5947; 1548-8675
• DOI: 10.1080/02755947.2012.675954

The study of movement in catfish via telemetry can be problematic because of transmitter expulsion. Information regarding transmitter retention in blue catfish Ictalurus furcatus is limited. We examined transmitter retention and physical condition after implantation in adult blue catfish (≥600 mm) for two surgical implantation methods. Fifteen fish were implanted with Vemco V16 transmitters that were left free floating in the abdominal cavity (traditional method). Another fifteen fish were implanted with capsules constructed to duplicate externally mounted Vemco V16 transmitters. These capsules were implanted in the abdominal cavity and then anchored to the pectoral girdle using sterile pseudo-monofilament suture (modified method). Fish were held in a flow-through circular tank for 244 d following surgery. Sixteen fish expelled their capsules, 10 from the traditional procedure and 6 from the modified procedure. Expulsions were observed between 23 and 243 d post surgery. The condition of fish with retained transmitters after 244 d, as measured by relative weight, was significantly higher for fish in the traditional treatment group. Gross necropsy revealed that retained traditionally implanted transmitters were free floating in the abdominal cavity with no visible interaction with internal organ structures. In the modified surgery group, retained transmitters remained tethered to the pectoral girdle but were located in various positions within the abdominal cavity, including encased in the intestine or stomach, and pushed through the body wall. Our study demonstrated unacceptable health effects associated with the modified procedure. We do not recommend it as a transmitter attachment method for telemetry studies of catfish movement. Further study is suggested to better determine the rates of retention associated with the traditional procedure that was tested.