Science Laboratory Technology




This work was done at the laboratory of the Fisheries and Marine Technology, Imo State polytechnic Umuagwo-Ohaji. Two plant products, Mynistic fragrans and Aframomum melegueta obtained from the local market were pulverized and dissolved in Alcohol and water at concentrations of 1gk, 1.sgk, 2gk, 2.sgk, 3gk, 3.sgk and 4gk. Sections of Clarias gariepinus (1cm Thinkness) were soaked in above solution for 24hours. These were smoke dried and allowed to condition the laboratory for 2days before introducing the insect pest, Demetes Maculatus. The insects were repelled by the treated fish for about 3days before they could does into it and establish. Dry powder treatment was administered at 1g-4g/10g fish. Myristica fragrans instantly repelled insects while Aframomum Melegenta did not. Myristica fragrans powder at all levels of treatment caused significantly (P<0.05) higher mortalities than in control experiment. Mynistica fragrans dissolved in water (HzO) did not produce significant (P>0.05) mortality at all concentrations. However Myristica in Alcohol treatment produced significantly higher mortalities over Nutmeg (Myristica fragrans) in water treatments Alcohol solution of Nutmeg at produced significantly (P<0.05) higher mentalities over all other concentrations. Treatment using Aligator pepper (Aframomum Melegueta) in water at 2g/L was significantly (P<0.05) differences were found between Nutmeg in Alcohol at 3g/L, Alcohol and Aligator treatment at 3.5g/L water and Aligator pepper at 2g/L. In powder treatments the highest significant mortalities were found in the highest doses 3.5g/10g fishes when compared with other doses and Aligator pepper (Aframomum Melegueta) were there were in mortalities.


Cover page——————————————————i
Title page——————————————————-ii
Table of content———————————————–vii
1.0 Introduction——————————————–1-5
2.0 Literature review————————————-6-10
3.0 Material and methods———————————-11
3.1 Handling of plant products—————————–11
3.2 Purchase and maintenances of insect culture.——–12
3.3 Preparation of fresh uninfected fish samples———12
3.4 Treatment of uninfected fish————————–13
3.5 Studies on mortality of D. maculates after contact infection——-14
3.6 Palatability test——————————————14
3.7 Summary of experimental plan ——————–15-17

4.1 Result—————————————————-18
4.1 Experimental findings——————————-19-20
4.2 Filling up ANOVA table ——————————21-26
4.3 Discussion——————————————–27-31
4.5 Conclusion & recommendation————————-32



Fish protein is known to be the best and cheapest source of animal protein (Olayide 1973) the loss of protein in dried fish due to known fish pest D. Macuatus has been variously qualified.

Fish is a perishable biomaterial especially in the tropics where high temperature and humidity accelerate spoilage and Biodeterioration of fish immediately after catch. As a result of this, efforts are primarily directed towards the preservation of fish for human food.

However, poor handling, inadequate processing facilities, lack of ice or storage facilities, remoteness of the fishing villages to urban market centers, poor distribution channels have drastically reduced fish utilization in the tropics (Ames,1992). Efforts at the use of synthetic insecticides and other methods to control D. Maculatus have not presented pleasant results. This has led to a search for alternative user friendly methods especially the use of botanicals to control D. Maculatus (Okorie et al 1991).

The use of chemicals has helped increase of yields obtained but one of the major problems with the constant use of chemicals is that resistance can be induced in target organisms. Biological method control has been preferred in some cases because it is selective with no side effect and cheap. Resistance to biological control is rare and biological control agents are self propagating and self perpetuating (Okigbo and Ikediugwu 2000; Okigbo, 2003—-2005).

Plants extracts have been used successful to control insect and pest in the tropics. (Amadioha and Obi, 1999; Onitade 2000. Emoghene, 2004).

The practice of applying synthetic insecticides has been found to be potentially dangerous when such fish is consumed. In some villages in Ghana where fish have been treated in this manner, people who consumed them, suffered blurred vision, dizziness and vomiting (Bull 1982).

Losses due to this polyphagons pest of products of animal origin has been properly documented for a very long time (Aret, 1964, Willams 1956, Proctor, 1970, Kimura and Takakura).

Dry fish is however susceptible to pest infestation. Osuji (1973) noted that D. Maculatus is the major pest of dry fish with occasional presence of others like Necrobia, Rufipes, Tubolium, Castenum, and Trogoderma, granamium. The two are pests of other products.

The importance of D. Maculatus in Nigeria has been highlited (Hayward 1961). Researches have extended to the use of extracts water and alcohol extracts of such botanicals as P. guineese, X. Aethropica, Myristica fragrans etc.

All these have proved effective but methods of extraction have proved to be very expensive and not even within the reach of the common market woman hawking her dry fish in the market. The crude powder though is effective in most cases but may be cumbersome in application and may be even negate the rates of application and add to the appearance of dried fish. In overall assessment may make managements and general handling a hell.

This study is seeking the best and most effective way of applying these botanicals to the fish so that it will appear like ordinary dry fish and infestation of D. maculates and possibly other pest.

We have designed a means of using water and alcohol (Industrial) reasoning that since they are edible solvents that could be use to infuse the active ingredients which had been rather extracted and tried into the fish with some botanicals; A. Melegueta and M. fragrans through soaking the fish to be preserved in such media. This is the reasoning that poor fish handlers can afford to do this.

The simple methods engaged could be steaming fish, boiling fish and soaking fish in such media in which different doses of the botanicals are soaked. The botanicals to be used are alligator pepper; A. Melegmeta and nutmeg myristica.

Our target is to find out the following;

  • Whether the active ingredients of M. fragrans and A. Melegueta can be infused into the fish through dissolving in water and absolute alcohol (Industrial) and still bring effect as then crude powders.
  • The rather ineffective A. Melegueta as powder whose water and alcohol extracts have been found to be effective were to see if it could be effective in this circumstance on D. Maculatus
  • If fish treated with solutions of these botanicals at different concentration will still be palatable and aesthetically attractive
  • Our over all objective in this finding is to find a cheap effective means of do it yourself preservation that can be within the reach of the common man in an environmentally friendly way.


Ablott, W.S, (1925). A method of computing the Effectiveness of an instecticide. J. Econ. Entomol., 18: 265-267.

Adedire C.O & Lajide L. (2000) effect of pulverized Plants. Materials on fish damage & growth performance of the fish/Beetle.

Berknower, M., 1994. Freezing to eradicate insect pests in textiles at Brodsworth Hall. Conservator, 18: 15-21.

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