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1.
The utility of visible implant (VI) tags for marking tropical river fish   总被引:2,自引:0,他引:2  
In tropical fisheries where ageing fish is often difficult, tagging programmes offer an important means to estimate growth parameters and mortality rates. The majority of tags are large and attached externally via a puncture in the muscle. These characteristics may cause significant biological effects which bias parameter estimates. Visible implant (VI) tags offer a more benign means to individually mark fish. The utility of VI tags for marking five species of tropical river fish was examined. The results indicate that the tag and tagging operation had no influence on either growth or mortality, although tag retention was poor compared with other studies. For three of the five species, the only suitable tagging location was highly inconspicuous and therefore inappropriate for tagging programmes that rely upon fishermen to return tagged fish. Alternative tagging locations may improve retention rates and the visibility of the tag.  相似文献   

2.
The development and testing of a visible implant elastomer pedigree‐marking system was evaluated in sunshine bass, Morone chrysops×Morone saxatilis, and white bass, M. chrysops (Rafinesque). These tags were tested in sunshine bass fingerlings at one of four subdermal body locations (posterior to the eye, dorsal fin musculature, caudal fin musculature or anal fin musculature). Tag visibility decreased with increased sunshine bass growth (63% after 56 days). Visibility differed among body locations, with the caudal and anal tagging locations having lower visibility. White bass fingerlings representing eight genetic groups were then tagged at one of two body locations (left or right subdermal along the dorsal musculature) using one of four fluorescent colours and reared for 42 days in a common garden growth trial. Tag visibility in white bass was 99.5% at 14 days, 98.2% at 28 days and 94.9% at 42 days after tagging. There was a significant change in weight among the eight genetic groups of white bass fingerlings after 42 days (P=0.03). Testing of this pedigree tagging system successfully identified phenotypically different groups of white bass fingerlings.  相似文献   

3.
To determine the efficacy of passive integrated transponder (PIT) tags for marking rohu Labeo rohita (Ham.) in the selective breeding programme, a series of experiments has been carried out at the Central Institute of Freshwater Aquaculture (CIFA) under the Indo–Norwegian project of ‘Selective breeding of rohu’. Six groups of rohu fingerlings with weight ranging from 2 g to 20 g were tagged with PIT tags to determine a suitable size range for tagging. Fingerlings weighing 8–15 g were found to be quite suitable for tagging with a PIT tag. Recovery of the PIT tag depends upon the survival of tagged fish under field conditions. Rejection of the PIT tag by rohu was observed to be only 0.05%. Through effective management practice, the survival of tagged fish increased up to 95%, and thus tag loss was minimized.  相似文献   

4.
鱼类育种实践中的个体标记技术   总被引:3,自引:0,他引:3  
本文对鱼类育种实践中所采用的鱼类个体标记方法及其优、缺点进行了综述。鱼类个体标记主要有外标和内标两种方式,每种标记方式中又有不同的具体方法。外标法主要包括鼻签、剪鳍、挂牌、烙印等,具有简便易行、成本较低等优点,但标记的保留率相对较低;内标法有染料标记、放射性同位素标记、荧光色素可见标记和被动整合雷达标记等,内标法的标记保留率较高,但成本也较高。内标法在标记效率和个体存活率上比外标法要好。  相似文献   

5.
Studies were conducted to determine the effect of stocking size and density of prawns in polyculture.
In one experiment, postlarval prawns (av. wt. 0.02 g) were stocked in six 0.02 ha earthen ponds at 35,00O/ha. Two ponds were stocked with tilapia fry (av. wt. 0.14 g) and two were stocked with tilapia fingerlings (av. wt. 30.1 g), each at 10,000/ha. Two control ponds had no tilapia. Tilipia stocking size had no effect on prawn growth. Mean weight of prawns after 70 days of culture ranged from a low of 4.5 g when cultured with tilapia fingerlings to a high of 6.6 when cultured in monoculture. Prawn survival was adversely affected by tilapia fry. Average prawn survival in tilapia fry ponds was 65% compared to 75% and 91%, respectively, in tilapia fingerling and monoculture ponds.
In a second experiment, postlarval prawns were stocked in nine 0.02 ha earthen ponds at 40,000/ ha. Six ponds were stocked with 30 g tilapia fingerlings, three at 5,000/ha and three at 15,000/ha. Three control ponds received prawns only. After 100 days of culture, prawn weight ranged from an average of 15.9 g in monoculture ponds to 11.5 g in polyculture ponds. Survival was highest (93.8%) in low density polyculture ponds. Survival was lowest (85.6%) in prawn monoculture ponds. Tilapia reproduction had a negative impact on shrimp production.  相似文献   

6.
Abstract  A hatchery experiment was organised to find out if the high loss rate of coded wire tags, noticed in connection with an Arctic charr Salvelinus alpinus (L.) restocking programme, was size-dependent and also to test head moulds for future taggings. Six moulds made by Northwest Marine Technology Inc. and five moulds made at the Finnish Game and Fisheries Research Institute were used. A total of 100 charr were tagged with standard-length coded wire tags using each mould. One-summer old charr at tagging were held for 534 days and two-summer old charr for 320 days. The tag loss rate varied between 0% and 54% and was negatively related to the size of the charr at tagging. The high loss rate was connected with the poor alignment of some moulds, such that a large proportion of the tags were located in the nasal cavity instead of the nasal cartilage. Testing of the moulds and careful grading of the fish for tagging is emphasised, especially if Arctic charr smaller than 20 g in weight are to be tagged.  相似文献   

7.
Two different colours (red and green) of visible implant elastomer (VIE) were used in Nile tilapia (Oreochromis niloticus). The visibility, location and retention of the VIE tags was investigated and any adverse effects on fish survival and growth determined. The use of VIE tags for monitoring individual fish during a bacterial challenge with either Streptococcus agalactiae or S. iniae was also studied. The results showed that VIE treated fish were lighter but not shorter than the non‐tagged control fish and that tagging caused no mortality. The retention of tags was better at the base of pectoral fin followed by the nasal area, lower abdomen, upper abdomen and branchiostegal rays inside the operculum. During the bacterial challenge experiment individual animals could be easily identified using the VIE tags. In this preliminary study, VIE tagging appears suitable for Nile tilapia research, as with other fish species, and could be a novel method to identify individual animals during microbial pathogenesis studies.  相似文献   

8.
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%.  相似文献   

9.
The success of the sea trout, Salmo trutta L., enhancement programme carried out in the Burrishoole catchment in the west of Ireland from 1993 until 1998 is reviewed in terms of the number of fish stocked, the number of fish which migrated to sea and the number which returned from sea during this period. The success of the programme is also evaluated in terms of the cost of producing parr for stocking and the subsequent value of returning post-smolts (0+ sea age) and rod caught fish. A total of 49 235 tagged fish were released into Lough Feeagh, between 1993 and 1998. Of these fish, 14 788 were microtagged and the remainder, 34 447 had either elastomer or alphanumeric visible implant (VI) tags. Tag loss rates at release varied from 3 to 5.7%. Over the course of the programme a maximum of 7801 fish migrated through the traps towards sea, of which 581, or 7.4%, returned. In any 1 yr a maximum 13.1% of fish returned from sea. The average cost of producing a parr for stocking out was €1.15, which translated into average values of €8.16 per smolt and €169 per returning post-smolt.  相似文献   

10.
The suitability of visible implant alphanumeric (VI-alpha) and passive integrated transponder (PIT)-tagging to individually identify seahorses (Hippocampus abdominalis) was assessed in two trials. For each trial, 24 seahorses were tagged and mortality, growth, tag retention and tag visibility/readability assessed, together with 24 control seahorses, over a period of 3 months. For VI-alpha tagging, a single tag was inserted under the skin between the first two anterior lateral tail rings of the seahorses. There was no difference in final seahorse length, wet weight, or mean SGR in tagged seahorses, compared with control seahorses, after 3 months. Tag retention was 100%, as was survival, in both treatments. Tag detection with the naked eye was generally poor but improved using LED blue light. However, readability of tag codes was highly variable and insufficiently reliable for VI-alpha to be suitable for identification of individual seahorses. In PIT-tagged seahorses, a single FDX-B transponder was inserted into the abdominal cavity of seahorses. There was also no difference in final seahorse length, wet weight, or mean SGR, compared with control seahorses, after 3 months. Tag retention was also 100%, as was survival in both treatments. Readability of transponders was reliable and quick using a compact reader. PIT-tagging is considered suitable for individual identification of large H. abdominalis.  相似文献   

11.
The effects of passive integrated transponder (PIT) tagging on the growth and survival of olive flounder, Paralichthys olivaceus (initial average mass ± SD: 502 g ± 14.3), were examined for 8 mo. Tag readability in relation to implant position (eyed‐side muscle, blind‐side muscle, and peritoneal cavity) was also documented. The overall weight gain of fish tagged in the eyed‐side muscle (444 g) was significantly less than control and tagged fish in the blind‐side muscle and peritoneal cavity, which showed 470–488 g of weight gain (KW, P < 0.001, N= 78, df = 3). Specific growth rates (%/d) did not differ significantly (P > 0.05) among control, blind‐side muscle, and peritoneal cavity groups. No significant (P > 0.05) difference in survival rate was found between treatment and control. The readability of PIT tags in all implanted positions was 100%. The average time spent tagging at each position was less than 30 sec. These results show that PIT tagging of olive flounder weighing approximately 500 g in the blind‐side muscle and peritoneal cavity is feasible and reliable with fewer negative effects on growth than observed on the eyed‐side muscle site trial.  相似文献   

12.
An important requirement of many breeding programmes for aquaculture species is the ability to identify organisms individually or at least by family. While a variety of external and internal tagging methods have been developed that can provide efficient identifications systems, most have specific drawbacks. The present study assessed the efficiency of an internal tagging method that can be applied to family selection programmes in crustacean species. Experiments were conducted to test the efficacy of applying visible implant elastomer (VIE) tags to juvenile giant freshwater prawn (GFP). The first experiment assessed performance of VIE tags in juvenile GFP of different size classes and stability of tags placed in different positions in the abdomen with different numbers of tags implanted. The second experiment applied VIE tags in a long term, large scale, field‐based farming experiment. The third experiment tested the reliability of the system. Results showed that juvenile GFP at 2 g were of suitable size for VIE tags with no negative effects evidence on growth and survival. Tag retention rates were above 97.8% in all experiments and tag readability rates were 100% with a correct assignment rate of 95% through to mature animal size of up to 170 g.  相似文献   

13.
The effect of two physical tagging systems, Visible Implant Elastomer (VIE) and Passive Integrated Transponder (PIT), was evaluated in red porgy (Pagrus pagrus) fingerlings, at different sizes. For VIE tagging, the weight classes were <1 and 1?C5?g and no tag effect was detected on fish growth. There was a significant difference in mortality between tagged and untagged <1?g fish, but not for the 1?C5?g fish. The tag loss rate was null for all sizes, however, tags showed fragmentation. This partial tag loss was evaluated and quantified. Seven VIE colours were compared and arranged from best to worst visibility: green, red, pink, orange, yellow, white and blue. For PIT tagging, 2?C6?g, 5?C10?g and 10?C20?g weight classes were analysed. There was no significant tag effect on fish growth, for any size, nor on mortality from 10?g. Tag loss rate ranged from 2.9 to 5.9%. These results demonstrate that, in red porgy, VIE is a successful tagging system from 2?g onwards whereas PIT system is successful from 10?g onwards. The combination of both systems allows traceability of fish from a very small size on, which is necessary for the implementation of genetic breeding programmes.  相似文献   

14.
Abstract –  To address the dearth of information on tagging effects and long-term survivorship of tagged fish in native and introduced species, laboratory and field investigations were undertaken on three non-native fish species (pumpkinseed Lepomis gibbosus ; topmouth gudgeon Pseudorasbora parva ; pikeperch Sander lucioperca ) tagged with coded-wire (CW), passive integrated transponder (PIT), radio (RT) telemetry and/or acoustic tags (AT), with survivorship of native brown trout ( Salmo trutta ) examined in the field. Laboratory results revealed high survivorship following tag attachment/insertion and resumption of feeding within 24–48 h of tagging (all mortalities could be attributed to an unrelated outbreak of fungal infection), with retention rates being high in both pumpkinseed and pikeperch but low in topmouth gudgeon (excluded from field studies). In the field, short-term post-operation survival was high in pikeperch, pumpkinseed and brown trout. In pumpkinseed and trout, 100% of RT fish survived a 24–30 day tracking study, with 60% and 80%, respectively, recaptured alive at least 3 months post-tagging. Of PIT tagged pumpkinseed, 44% were recaptured (after 6–18 months), with small-sized, CW-tagged fish (0.38 g weight) captured up to 1 year after tagging. In pikeperch, all AT fish except one (the smallest specimen) survived their full expected tracking period (i.e. tag life) – the single lost specimen survived at least half of its expected tracking period (i.e. 6 month battery life). Overall, the tagging methods used were highly effective in pumpkinseed and pikeperch, showing good retention and survival, but PIT tagging of topmouth gudgeon was plagued by low survivorship and tag rejection.  相似文献   

15.
Frozen beef liver fed at dietary levels of 5, 10, 15, 20, and 25% (dry weight) to postlarval Mucrobruchium rosenbergii was evaluated as a supplement to Mna Trout Chow No. 2. Final mean wet weights and yields of prawns fed 15, 20, and 25% beef liver were significantly higher than those of prawns that received 5 and 10% levels. Survival rates and food conversion ratios of dry matter fed to wet biomass produced were not significantly different among treatments. The suitability of 47 fresh and frozen fruits and vegetables as dietary supplements was tested. Fourteen fruits and vegetables sank and were readily consumed by prawns, and seven (fresh orange and sweet potato, and frozen banana, carrot tops, butternut squash, yellow squash, and turnip greens) were tested as supplements (10% dry weight of the total ration) to trout chow and 15% beef liver. There were no significant differences ( P < 0.05) in final mean weight, survival, yield, or food conversion ratio. Pigmentation of prams fed carrot tops or turnip greens was enhanced. No significant differences in final mean weight, yield, or survival were found when frozen banana was evaluated at levels of 0, 5,10,15, and 20% as a supplement to trout chow and 15% beef liver. Food conversion ratios for prawns fed 15 and 20% levels of banana were not different from those fed 10%, but were significantly higher than for prawns fed the 0 and 5% levels. Thus, a diet of Purina Trout Chow No. 2 plus 15% beef liver gives good results with postlarval M. rosenbergii in aquaria. Largescale testing and an economic analysis are needed to determine if this diet is practical for commercial prawn nurseries.  相似文献   

16.
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.  相似文献   

17.
本文根据辽东湾中国对虾标志放流实验与重捕资料,对辽东湾中国对虾放流场的选择、种苗的放流规格和放流增殖效果进行了研究。根据上述实验分析表明,在辽河口海区进行对虾放流增殖是较理想的场所,在秋汛生产期洄游分布遍及辽东湾传统的中心渔场;放流种苗的适宜体长规格为5cm以上,回捕率较高,最高达3.31%。这将对辽东湾生产性对虾放流提供科学的依据。  相似文献   

18.
Assessments of stock enhancement programmes for European lobsters (Homarus gammarus) require mark‐recapture analysis of stocked individuals. However, established tag technology is deemed unsuitable for extensive use by many current lobster hatcheries, particularly upon the early juvenile stages. We tested the suitability of fluorescent Visible Implant Elastomer (VIE) tags for use in 5‐month‐old juvenile lobsters. Three treatment groups comprising 348 cultured lobsters in total were used to examine survival, growth and tag retention, and to assess mobility, shelter use and moulting behaviours. Tagging had no significant effect on lobster survival, growth, mobility, shelter use or moult frequency. Survival over 7 weeks was 75% among lobsters tagged with two elastomers, 76% in those with one elastomer and 74% among untagged controls. Mortality during moulting did not increase in tagged (6%) compared to untagged lobsters (9%). We found no evidence that VIE tags cause any negative effects that would be expected to inhibit survival upon wild release, but tag loss had reached 12% in both tagged treatments after 7 weeks and showed no sign of abating. Our study suggests that VIEs effectiveness in discerning cultured lobsters long after wild release may be limited when used in smaller juveniles.  相似文献   

19.
Electronic tags have become a common tool in fish research, enhancing our understanding of how fish interact with their environment and move among different habitats, for estimating mortality and recording internal physiological states. An often‐untested assumption of electronic tagging studies is that tagged fish are representative of untagged conspecifics and thus show ‘normal’ behaviour (e.g. movement rates, swimming activity, feeding). Here, we use a unique data set for potamadromous walleye (Sander vitreus) in Lake Huron and Lake Erie tributaries to assess whether the lack of appropriate controls in electronic tagging could seriously affect behavioural data. We used fish tagged in previous years and compared their migratory behaviour during the spawning season to fish tagged in a current year at the same location. The objective of the study was to determine whether intracoelomic acoustic tag implantation altered downstream movement of walleye after spawning. Fish tagged in a given season travelled slower downstream from two river spawning sites than fish tagged in previous years. Fish tagged one or two years earlier showed no differences between each other in downstream travel time, in contrast to fish tagged in a given year. Our results support notions that standard collection and intracoelomic tagging procedures can alter short‐term behaviour (i.e. days, weeks, months), and as such, researchers should use caution when interpreting data collected over such time periods. Further, whenever possible, researchers should also explicitly evaluate post‐tagging effects on behaviour as part of their experimental objectives.  相似文献   

20.
Abstract – Despite its small size [adult: 60–130 mm, total length (TL)] and limited home range, the round goby (Neogobius melanostomus) has quickly become established throughout the Laurentian Great Lakes. Little information is available, however, on the natural dispersal pattern of this species. This capture–mark–recapture study utilised alphanumeric tags subcutaneously inserted into round gobies (n = 1228) along a 550‐m stretch of the Duluth–Superior Harbor shoreline to observe their movement over a 13‐month period. Recaptured round gobies (n = 415) exhibited highly leptokurtic movement distributions, and movement events were not correlated with fish size, gender or month. Our work indicates that round gobies >50 mm (TL) generally occupy an area less than the minimum sampling interval (25 m); however, occasional movement up to 50 m per day could facilitate range expansion in the Laurentian Great Lakes.  相似文献   

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