Untagged Controls Research Articles

Evaluation of visible implant elastomer tags for tagging juvenile gilthead seabream (Sparus auratus L.); effects on growth, mortality, handling time and tag loss

The use of the fluorescent visible implant elastomer (VIE) tagging system in juvenile gilthead seabream, Sparus auratus L., between 7 and 18 g was examined. Four different colours (red, green, orange and yellow), three body positions (dorsal, lateral and caudal) and two orientations (horizontal and vertical) were tested. The mean tag application time for each fish was 15.7±0.32 s. There was no mortality associated with the method of tagging. The most visible tag colour was red. Injection orientation had a significant effect on length, width, fragmentation and fluorescent intensity of the tag. Horizontal tagging is recommended because of high fluorescent intensity, low fragmentation and for double tagging. There were no differences in growth between untagged controls and the VIE-tagged fish.

Radio Tag Retention and Tag-Related Mortality among Adult Sockeye Salmon

Abstract Tag retention and tag-related mortality are concerns for any tagging study but are rarely estimated. We assessed retention and mortality rates for esophageal radio tag implants in adult sockeye salmon Oncorhynchus nerka. Migrating sockeye salmon captured at the outlet of Lake Clark, Alaska, were implanted with one of four different radio tags (14.5 × 43 mm (diameter × length), 14.5 × 49 mm, 16 × 46 mm, and 19 × 51 mm). Fish were observed for 15 to 35 d after tagging to determine retention and mortality rates. The overall tag retention rate was high (0.98; 95% confidence interval (CI), 0.92-1.00; minimum, 33 d), with one loss of a 19-mm × 51- mm tag. Mortality of tagged sockeye salmon (0.02; 95% CI, 0-0.08) was similar to that of untagged controls (0.03 (0-0.15)). Sockeye salmon with body lengths (mid-eye to tail fork) of 585-649 mm retained tags as large as 19 × 51 mm and those with body lengths of 499-628 mm retained tags as small as 14.5 × 43 mm for a minimum of 33 d with no increase in mortali...

Evaluation of visible implant fluorescent elastomer (VIE) as a tagging technique for spiny lobsters (Jasus edwardsii)

Tagging crustaceans for growth studies is often difficult because external tags/marks may be shed or cause mortalities during moulting. In this investigation, the effectiveness of visible implant fluorescent elastomer (VIE) as an invasive tagging technique for spiny lobsters (Jasus edwardsii) was investigated over a 6-month period. Tagged lobsters were either tagged with the tag running transversely across the ventral abdominal superficial flexor muscle block (transverse VIE) in the second abdominal segment, or in-line with the ventral abdominal superficial flexor muscle block (longitudinal VIE). Non-tagged lobsters were used as the control. At the conclusion of the investigation there were no differences in growth or survival between tagged lobsters and untagged controls and tag retention rates were 100% for both tagging treatments over the 6-month period. Tag visibility was high after six months in both tagging treatments, although higher in the longitudinal VIE treatment. Tag fragmentation was frequent in the transverse VIE treatment, but infrequent in the longitudinal VIE treatment. We conclude that VIE is an effective tagging technique for J. edwardsii in terms of the high degree of tag visibility, retention, and non-detrimental impact on the growth and survival of tagged animals, provided the VIE tag is injected in-line with the orientation of the muscle fibres/tissue.

Functional expression of distinct NMDA channel subunits tagged with green fluorescent protein in hippocampal neurons in culture

We generated expression vectors for N-terminally green fluorescent protein -tagged NR2A and NR2B subunits (GFP-NR2A and GFP-NR2B). Both constructs expressed GFP and formed functional NMDA channels with similar properties to untagged controls when co-transfected with NR1 subunit partner in HEK293 cells. Primary cultured hippocampal neurons were transfected at five days in vitro with these vectors. Fifteen days after transfection, well-defined GFP clusters were observed for both GFP-NR2A and GFP-NR2B subunits being co-localized with endogenous NR1 subunit. Whole-cell recordings showed that the GFP-NR2A subunit determined the decay of NMDA-mediated miniature spontaneous excitatory postsynaptic currents (NMDA-mEPSCs) in transfected neurons. Live staining with anti-GFP antibody demonstrated the surface expression of GFP-NR2A and GFP-NR2B subunits that was partly co-localized a presynaptic marker. Localization of NMDA receptor clusters in dendrites was studied by co-transfection of CFP-actin and GFP-NR2 subunits followed by anti-GFP surface staining. Within one week after plating most surface NMDAR clusters were distributed on dendritic shafts. Later in development, a large portion of surface clusters for both GFP-NR2A and GFP-NR2B subunits were clearly localized at dendritic spines. Our report provides the basis for studies of NMDA receptor location together with dendritic dynamics in living neurons during synaptogenesis in vitro.

Long-term effect of radio-tagging on the swimming performance of pikeperch

Critical swimming speed of adult pikeperch Stizostedion lucioperca (L T 53-72 cm) that had spent one year in the field after tagging with body-implanted radio transmitters were not affected compared with untagged controls.

Effects of telemetry transmitters on swimming performance of adult Atlantic salmon

Swimming performance and blood physiology of adult Atlantic salmon (1021–2338 g, total body length 45–59 cm) were not affected when equipped with external (two sizes) or body‐implanted telemetry transmitters compared with untagged controls.

Effects of telemetry transmitters on swimming performance of adult Atlantic salmon

Swimming performance and blood physiology of adult Atlantic salmon (1021–2338 g, total body length 45–59 cm) were not affected when equipped with external (two sizes) or body-implanted telemetry transmitters compared with untagged controls.

Tagging sea urchins: a new technique for individual identification

The green sea urchin, Strongylocentrotus droebachiensis, from northern Norway was implanted with a passive integrated transponder (PIT) tag. There was no tagging mortality, and the long term survival of tagged individuals over a 16 month period was not significantly different from the survival of untagged controls. Growth of the tagged sea urchins appeared normal. No significant differences were detected between the mean diameters of sea urchins in the tagged group and in the control group, and Von Bertalanffy growth curve parameters for the tagged sea urchins fell within the range of previously published estimates for S. droebachiensis. Tag retention was 100% for animals larger than 25 mm in diameter. This size also represents the minimum size for successful implantation of the PIT tag. Tag detection was under 100% on the first trial owing to the inability of the tagging equipment to detect tags which were perpendicular to the signal from the reading device. The PIT tag compares favourably with existing techniques for tagging sea urchins, its indefinite life span allowing unlimited non-destructive sampling of tagged individuals. PIT tags have immediate potential for application in broodstock management and laboratory experiments, but the potential for field applications is still limited by the lack of submersible detection equipment.

Anchor tags affect swimming performance and growth of juvenile red drum(Sciaenops ocellatus)

Swimming efficiency and growth of anchor‐tagged red drum (Sciaenops ocellatus) juveniles were compared with untagged controls. The O2 consumption of fish swimming at different speeds was measured in a Blazka‐type respirometer. Daily growth rates of tagged and untagged red drum were compared over 42 d of feeding fixed rations of live mosquitofish (Gambusia affinis) to siblings held individually in 380 L tanks. At swimming speeds of ≤1.0 body lengths per second (bl s‐1), no differences in O2 consumption were found. However, at speeds of 1.5–2.5 bl s‐1, tagged red drum O2 consumption was significantly greater (by 36–39%) than that of untagged fish (ANOVA, P<0.05), indicating a substantially impaired swimming efficiency. Daily growth rates of tagged and untagged fish also differed significantly (P < 0.02). Tagged fish grew at a mean rate of 0.95 mm d‐1 and 1.45 g d‐1, while untagged fish (controls) grew at 1.14 mm d‐1 and 1.62 g d‐1. Results suggest that internal anchor tags, which weighed less than 1% offish...

Techniques for radio-tagging pheasant chicks

Although chick mortality is high in many precocial bird species, it is particularly difficult to determine the causes of death. We therefore developed techniques for radio-tagging Ring-necked Pheasant Phasianus colchicus chicks within 5 days of hatching, by catching the adult female with her brood. Eleven chicks with wing-tag radios had lower survival than 17 untagged chicks in the same broods, but the survival of 13 chicks with glue-mounted radios was the same as that of 10 untagged controls.

Effect of intraperitoneal passive implantable transponder (PIT) tags on the growth and survival of juvenile snapper, Pagrus auratus (Bloch and Schneider)

Abstract. This study examined whether passive implantable transponder (PIT) tags could be used to mark individually juvenile snapper, Pagrus auratus (Bloch and Schneider), without affecting their growth. Fifty juvenile snapper (25 tagged and 25 untagged controls) were placed in each of four 2000–1 tanks. At the start of the experiment the snapper had a mean weight of 59 ± 18g (SD). After 70 days, the mean weight of all fish was 115 ± 31 g (SD) and there was no significant difference between the growth of tagged and untagged fish. Apparent tag loss ranged from 4 to 8%.

Immunisation of cattle against theileriosis in Nakuru District of Kenya by infection and treatment and the introduction of unconventional tick control

One hundred and one cross European-Boran cattle (50 cows and 51 calves), on a farm in Nakuru District, Kenya, were immunised against theileriosis using Theileria parva lawrencei and Theileria parva parva stocks from another district of Kenya. The stabilates used were T.p.lawrencei (Mara III) used at 10 −1.7 dilution and T.p.parva (Kilae) used at 10 −1.0 dilution. The stabilates were combined and inoculated simultaneously with a short-acting formulation of oxytetracycline hydrochloride given intramuscularly at 10 mg kg −1 body weight and was repeated on Day 4 after inoculation of the stabilate. Most of the theileriosis challenge on the farm was thought to be derived directly from the African buffalo ( Syncerus caffer). Nine percent of the cattle had significant indirect fluorescent antibody (IFA) titres before the immunisation and 99% after immunisation. The immunised cattle were exposed to tick-borne disease challenge on the farm by withdrawal of acaricide cover. The immunised cattle were divided into five groups plus two susceptible control cows and two calves for each group. Cattle in four of the groups had acaricidal ear tags, each group having a different type, applied to both ears and the fifth group remained untagged. The animals remained without conventional acaricide application for 134 days. Ten out of 20 (50%) non-immunised control cattle became T.p.lawrencei reactors while only one out of 97 (1%) of the immunised cattle reacted. A frequent complication noted was mild infections due to unidentified Theileria sp. which required expert differentiation from T.parva infections. An additional group of ten steers whose tick load was removed by hand at weekly intervals was introduced 79 days after exposure; these had no tick control and four became T.p.lawrencei reactors. Of 12 calves born during the exposure period and without tick control, four became theilerial reactors and one died. The application of acaricidal tags however, reduced tick infestation levels considerably compared with untagged controls but did not prevent transmission of theileriosis with the possible exception of tags on Group 4. A number of transient low grade fevers were noted and attributed to Theileria sp., Ehrlichia bovis, Ehrlichia (Cytoecetes) ondiri and Borrelia theileri infections, none of which were fatal. One immunised animal died of acute dual infection of Babesia bigemina and Borrelia theileri after acaricide control by spraying was re-introduced but no Anaplasma infections were detected. An analysis of the economic effects of immunisation was made.

The effect of ultrasonic tags on the growth rates of Atlantic salmon, Salmo salar L., parr of varying size just prior to smolting

The attachment of dummy, ultrasonic, acoustic tags, of the Stirling Mk. VI design, to pre‐smolt Atlantic salmon parr significantly affected fish growth rates. Fish less than 160 mm in length lost weight and showed no change in length. Fish over 160 mm in length put on weight, though at a rate significantly lower than that of untagged controls. For fish between 160 and 180mm in length, the increase in length was significantly smaller in tagged fish than in untagged controls. Over 180 mm in length, no difference could be detected in the length gains of tagged and untagged fish.Smaller tagged fish gave up maintaining station and showed signs of distress at an earlier stage in the experiment than larger tagged fish. Tag‐related mortality was inversely related to fish size. All but two of the control fish survived the experiment and continued to maintain station throughout.The results suggest that the minimum length of Atlantic salmon parr on which this design of acoustic tag could be employed is 160 mm, and that caution is needed in the interpretation of track lengths longer than l0 daysof parr in the size range 160–180 mm.

Histopathology of the Internal Anchor Tag in Spot and Spotted Seatrout

Abstract Pathological tissue changes elicited by an internal anchor tag in spot Leiostomus xanthurus and spotted seatrout Cynoscion nebulosus were evaluated histologically. Forty-five spot (32 tagged fish and 13 untagged controls) and 13 tagged spotted seatrout were sampled periodically from 4 h to 4 months posttagging. Early tissue changes (4 h-4 d posttagging) in both species were characterized by acute inflammation and irritation. Changes included hemorrhage, fibrin exudation, extravasation of leukocytes, epidermal hyperplasia and spongiosis, and necrosis in exposed myotomes. Tags were progressively encapsulated and sequestered by fibrogranulation tissue in a similar sequence in both species, commencing with deposition and organization of fibrin at the tag surface. This early fibrinous capsule (at day 2) was infiltrated by leukocytes and fibroblasts, and by day 4–7 it was thickened, highly cellular, and well vascularized. Deposition of collagen within the granulation tissue capsule increased progressiv...

Tag loss and mortality rates of a small tropical demersal fish species, Lutjanus carponotatus (Pisces : Lutjanidae), tagged with dart and anchor tags

The shedding rate of FD-67 anchor tags from L. carponotatus was significantly lower than that of FT-2 dart tags. Mortality in fish tagged with either the FT-2 dart or the FD-67 anchor tags was significantly higher than in the untagged controls. There was no significant difference between mortalities caused by the two types of tag. Combining tag shedding and tag-induced mortality, the FT-2 dart tag produced a significantly greater rate of disappearance of tagged fish from a tagged population. Tag-induced mortality was highest during the first week after tagging and greatly reduced thereafter.

Mortality of Juvenile Brown Shrimp Penaeus aztecus Associated with Streamer Tags

Immature brown shrimp were marked with plastic streamer tags, then observed in large tanks for the effect of tags on mortality under a variety of pre- and post-tagging treatment regimes. Except where tagged animals were held at low density (9 animals/m2) and with few untagged conspecifics (2/m2), mortality was about 50% higher among tagged animals than among untagged controls. Differences among treatment groups in the number of handling steps, the wound caused by the tagging needle, the duration of high-density holding prior to release, and the sex of test animals were independent of mortality. The identity of the tagger and the size and condition of animals selected for tags were associated with small differences in survival in certain trials. Evidence from direct observation and from damage to tags suggested that mortality was higher among tagged animals because tags evoked attacks from untagged conspecifics and (in one trial) fish. In light of contrary evidence from some earlier studies, the clearer water and greater holding density in our study may have promoted tag-induced mortality by increasing the probability of interactions among animals.

Iron pyriets and calamine

One hundred and one cross European-Boran cattle (50 cows and 51 calves), on a farm in Nakuru District, Kenya, were immunised against theileriosis using Theileria parva lawrencei and Theileria parva parva stocks from another district of Kenya. The stabilates used were T.p.lawrencei (Mara III) used at 10−1.7 dilution and T.p.parva (Kilae) used at 10−1.0 dilution. The stabilates were combined and inoculated simultaneously with a short-acting formulation of oxytetracycline hydrochloride given intramuscularly at 10 mg kg−1 body weight and was repeated on Day 4 after inoculation of the stabilate. Most of the theileriosis challenge on the farm was thought to be derived directly from the African buffalo (Syncerus caffer).Nine percent of the cattle had significant indirect fluorescent antibody (IFA) titres before the immunisation and 99% after immunisation. The immunised cattle were exposed to tick-borne disease challenge on the farm by withdrawal of acaricide cover. The immunised cattle were divided into five groups plus two susceptible control cows and two calves for each group. Cattle in four of the groups had acaricidal ear tags, each group having a different type, applied to both ears and the fifth group remained untagged. The animals remained without conventional acaricide application for 134 days. Ten out of 20 (50%) non-immunised control cattle became T.p.lawrencei reactors while only one out of 97 (1%) of the immunised cattle reacted. A frequent complication noted was mild infections due to unidentified Theileria sp. which required expert differentiation from T.parva infections.An additional group of ten steers whose tick load was removed by hand at weekly intervals was introduced 79 days after exposure; these had no tick control and four became T.p.lawrencei reactors. Of 12 calves born during the exposure period and without tick control, four became theilerial reactors and one died. The application of acaricidal tags however, reduced tick infestation levels considerably compared with untagged controls but did not prevent transmission of theileriosis with the possible exception of tags on Group 4. A number of transient low grade fevers were noted and attributed to Theileria sp., Ehrlichia bovis, Ehrlichia (Cytoecetes) ondiri and Borrelia theileri infections, none of which were fatal. One immunised animal died of acute dual infection of Babesia bigemina and Borrelia theileri after acaricide control by spraying was re-introduced but no Anaplasma infections were detected. An analysis of the economic effects of immunisation was made.