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Research Article
 

Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)



M.S. El-Sherif, M.T. Ahmed, M.A. El-Danasoury and Nagwa H.K. El-Nwishy
 
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ABSTRACT

Diazinon was used in the laboratorial study to investigate its biochemical effect on tilapia as it is the most popular fish in Egypt. Two hundred and twenty appeared 40±2 g adult male Nile tilapia were reared in glass aquaria of 60 L capacity, provided with a good air supply and dechlorinated tap water, Fish were maintained under suitable condition for the fish growth. Results of the study are summarized as follow: (1) The bioassay test revealed that the LC50 for tilapia after 96 h of exposure was 2.8 ppm, (2) Fish was very excited after being exposed to lethal concentrations of diazinon (5, 10, 200 ppm) for 96 h. Meanwhile, fish exposed to sublethal concentrations of diazinon for 30 days didn’t cause mortality to fish and (3) Exposing fish to 0.28 and 1.87 ppm for 30 days caused the following changes: (A) A reduction in total protein content in muscles up to 13.69 and 21.5% for 0.28 and 1.87 ppm, respectively, (B) A reduction in total protein content in blood serum up to 22.23 and 24.32% for 0.28 and 1.87 ppm, respectively and (c) 52, 27 and 6.8 kDa proteins were not scanned in the treated or the recovered samples in both treatments, a slight reduction in the 33.55, 31.72, 24.31 and 20.8 kDa proteins in both treatments, (4) Exposing the treated fish to 7 days of recovery in un poisoned water caused the following changes: (A) A recovery in total protein content in muscles up to 95.59 and 90.58% for 0.28 and 1.87 ppm, respectively, (B) A recovery in total protein content in blood serum up to 89.36 and 95.14% for 0.28 and 1.87 ppm, respectively and (C) 52.27 and 6.8 kDa proteins were still not scanned after recovery of both treatments. A slight increase in the rest of affected proteins after recovery of both treatments was recorded. Therefore, it can be emphasized for good environmental administration of the water bodies to save human health and environment from the dangerous pesticides.

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  How to cite this article:

M.S. El-Sherif, M.T. Ahmed, M.A. El-Danasoury and Nagwa H.K. El-Nwishy, 2009. Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus). Journal of Fisheries and Aquatic Science, 4: 169-177.

DOI: 10.3923/jfas.2009.169.177

URL: https://scialert.net/abstract/?doi=jfas.2009.169.177
 

INTRODUCTION

The intensive agriculture regime in Egypt was designed to employ the land at its maximum uses. This partially covers the needed food by people live in this over populated country. By this strategy, the use of intensive pesticides in controlling pasts and diseases became common (Abdelhamid, 2003, 2005).

Subsequently, the food chain including fish production was affected negatively due to the toxicity of the pesticides uses (Abdel Fattah, 1992; Tawfic et al., 2002).

The present investigation was carried out in order to study the physiological and biochemical changes in quality and quantity of protein of Tilapia fish due to its exposure to Diazinon pesticide found in the waterways and lacks.

MATERIALS AND METHODS

Toxicity tests and some biochemical determinations were performed on tilapia fish (O. niloticus) at the Laboratory of Plant Protection. Faculty of Agriculture, Suez Canal University, Ismailia, Egypt-in season 2006. The tested compound (Diazinon) was a product of ADWIA Company, its concentration was 60% and it was brought from the Agricultural Requirements and Equipments market. The tested compound was reported by Kamrin (1997).

Tested Fish
Two hundred and twenty appeared uniform 40±2 g adult male Nile tilapia, O. niloticus were used in the experiment. They were provided from, Al-Tal Alkber fish farm, Ismaila, Egypt. Fish were transported live in tanks supplied with air pumps to the laboratory where they were reared in glass aquaria of 60 L capacity, provided with a good air supply and dechlorinated tap water. Fish were fed on commercial pellets contain 30% protein twice a day for 15 days. Feeding rate was made by 4% of fish weight (NRC, 1993). Fish was maintained in natural illuminating system under normal prevailing photoperiod conditions. Water temperature was maintained at about 25 ±1°C and water pH 7.7±0.5 which is suitable for the fish growth (Brown and Gratzek, 1979).

Toxicity Studies
This study was designed to examine the influence of both acute and chronic toxicity of diazinon on biochemical parameters of tilapia O. niloticus.

Acute Exposure
Approximately 150 healthy fish (10 fish/aquarium, 3 replicates/treatment) at equal size and length were divided in groups in aquaria and then fish was starved for 2 days before the test was performed. Fish were exposed to series of concentrations of the tasted pesticide (diazinon) to determine 50% lethal concentration (LC50); 5, 10, 50 and 200 mg L-1 for 96 h. Control fish was maintained in similar aquaria that contain only clean dechlorinated tap water. Feeding was stopped within the exposure time. And behavioral changes and clinical signs were recorded. Dead fish was removed from the aquaria as soon as possible to avoid polluting the contained water causing changes in the aquaria’s maintained conditions. Mortality was recorded each 24 h. Results were then subjected to probit analysis (Finney, 1971) to produce regression lines and to determine LC50 and line slopes.

Chronic Exposure
Sixty fish were exposed to the LC10 and LC33.5 of diazinon (30 fish for each) for 30 days which rarely, if ever, occurs under natural conditions, (Scholz et al., 2000). Fish were fed on 30% protein pellets, the pellets were brought from the Fish Research Center at Suez Canal University. Water was changed each 96 h to avoid the increase of ammonia level in water. At the end of the exposure interval, samples were randomly taken from the aquaria and then fish were removed from the treated aquaria to be transferred, for recovery, in other similar aquaria for 7 days, provided with clean dechlorinated tap water. Also, control fish were kept for a similar period in similar conditions. At the end of this recovery interval, new samples were taken from the aquaria and biochemical assessment was conducted on them.

Blood Sampling
Blood samples were taken from the tested fish to be biochemically analyzed. Fish were anaesthetized in ethyl 3-aminobenzoat methanesulphat (MS 222) by dissolving 0.02 g of MS 222 L-1 of water, then dipping the fish in it for 30 sec. Blood plasma was obtained by direct puncture of the heart with a heparinized injection, as heparin is a good antithrombin anticoagulant recommended for most fresh water fish (Smit and Hattingh, 1980); the sample was then collected in eppendorf tubes. On the other hand, Blood sampling of serum was obtained by direct puncture of the heart with an injection without using any antithrombin anticoagulant.

Biochemical Studies
Total protein was measured in fish blood serum and muscles by using a total protein kit (Henry, 1964). Proteins changes due to the lethal and sublethal concentrations of diazinon in the isolated muscles were identified using Sodium Dodecylsulfate Polyacrylamide Gel Electrophoresis (SDS/PAGE) by the method of Laemmili (1970).

Statistic Analysis
Data were statistically analyzed to test the significant differences (p<0.05) using SAS (1998).

RESULTS AND DISCUSSION

The Bioassay and Toxicity Studies
Results of the present study showed that LC50 of diazinon for 96 h was 2.8 mg L-1. LC50, MLC50 and the slope of diazinon are shown in Table 1.

Results reported by US EPA (1995) show close results with rainbow trout, while other fishes showed higher results; LC50 for Sheepshead minnows juveniles was 1400 μg L-1 (Goodman et al., 1979). Killifish 48 h LC50 was 4400 ppb for diazinon and 220 ppb for the diazoxon (Tsuda et al., 1997). Ninety 6 h LC50 for common carp juveniles was 26.7 mg L-1 of basudin 600 EW (preparation which is 16.0 mg L of diazinon), (Svoboda et al., 2001) and 839 μg L-1 for congeneric rainbow trout (Oncorhynchus mykiss), 2620 μg L-1 for Oncorhynchus clarki (Novartis, 1997). 770 ppb for Brook trout (Salvelinus fon tinalis), 7800 ppb Fathead minnow (Pimephales promelas), 460 ppb for bluegill sunfish (Lepomis macrochirus) (Allison and Hermanutz, 1977).

There has been different opinions reported about diazinon toxicity; Scholz et al. (2000) suggested that diazinon concentrations in nature aquatic ecosystems are more commonly less than 10 μg L-1; these concentrations, lasting for only a few days, are unlikely to kill fish outright. This difference of results and conclusions can possibly be related to differences of conditions on which each experiment was processed; such as containing water parameters, physiological differences between fish species and sexes since that salt water fish are more susceptible than freshwater fish to pollution (Kamrin, 1997). Also, differences in feeding types and habitats and pond capacity can be sources of differentiations. Moreover, differential sensitivity of various species to diazinon is largely due to the transformation rates within those species as suggested by Fujii and Asaka (1982). Differences in diazinon toxicity among various spices of fish could strongly be related to metabolic balances in the liver and with the features of the target enzyme as suggested by Keizer et al. (1995).

Table 1: Toxicity of diazinon on Nile Tiapia
Image for - Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)
MLC50: Molar LC50 = LC50/Molecular weight of compound

Behavior Response and Clinical Signs of Diazinon on Nile Tilapia
Acute Exposure
After exposing fish to lethal concentrations of diazinon (200, 50, 10 and 5 mg L-1), fish were notably excited. They swam around erratically and very rapidly and tried to jump out of the container. They surfaced gulping air. Their eyes were surrounded with black circles. In latter stages of exposure, the exposed excited fish laid on their sides on the bottom of the container, making very slight movement. Fish died within less than an hour from the exposure time when concentrations were equal to/or higher than 10 mg L-1. By the time fish died, they were all turned black. The dead fish which were exposed to 2.8 mg L-1, showed approximately similar clinical signs; they showed rapid movements at the first few hours of the exposure, then they swam less rapidly. Later, they laid on their sides on the bottom of the container till death, fish died within 96 h. Observed clinical signs caused by acute exposure are shown in Table 2.

Chronic Exposure
When fish was exposed to sublethal concentrations of Diazinon, LC10 and LC33.5 (0.28 and 1.87 mg L-1, respectively), fast movements of operculum and mouth was observed during the first 7 days. Later, fish skin turned black and the operculum moved normally. At the end of the exposure period, dark circles were noticed surrounding the eyes. No abnormal swimming activity was observed. No mortality occurred in the containers. Recovered fish showed lighter skin color, the black circles around the eyes were recovered. This agrees with the determinations reported by (Vaid and Mishra, 1999) that fish show a remarkable recovery against their toxicity when the source of toxicity is vanished. Rath and Misra (1981) reported that the degree of recovery follows an inverse relationship with the time of exposure, however, observed clinical signs caused by chronic exposure are shown in Table 3. The changes in skin colour in fish is in apart controlled by the sympathetic nervous system, which is probably affected by the exposure to Diazinon which is a nerve poisonous that affects the nervous system as the a main target to its activity. Color is most likely affected and regulated by a Melanophore Stimulating Hormone (MSH) as well when fish is stressed.

The observed fast movements of the operculum can be related to the cytochromoxidase which is responsible of the respiration system, most likely, when fish were stressed by the exposure, the enzyme was affected and resulted in reducing the efficiency of the extracting the oxygen from the water causing those fast movements of both, the mouth and the operculum of the fish in trying to come over the shortage of oxygen. Eventually when fish is exhausted by those fast movements and the shortage of oxygen, the movements are slowed gradually. Fish lost the appetite of food when they were treated with Diazinon for a chronic exposure; this is probably because the energy of the fish is almost totally directed toward resisting the pollutant effect on the biochemical functions of its body. The stored energy is then used instead of consuming food.

Table 2: Clinical signs of acute toxicity
Image for - Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)

Table 3: Clinical signs of chronic toxicity
Image for - Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)

El-Khateib and Afifi (1993) suggested that the onset of death due to the exposure with Diazinon is related to the nerve hemorrhagic gills and the lamellar effusion which cause reduction of the respiratory efficiency resulting in acute death. The entrance of the Diazinon was most likely by gills since toxicants enter the blood stream through the gills or/and gastrointestinal tract as reported by Doving (1991). There are many agreements with the result of this study; Beauvais et al. (2000) reported significant changes in swimming speed and distance in larval rainbow trout (Oncorhynchus mykiss) after been exposed to diazinon. They suggested that there was a correlation between physiological and behavioral changes in fish as well as in mammals. In addition, Moore and Waring (1998) suggested dangerous effect of Diazinon on the population of salmonids resulted from the effect of diazinon on the olfactory system of mature male Atlantic salmon (Salmo salar), which in sequence led to losing the ability of recognizing the prostagaglandin F sub (2 alpa) and ovulated female urine and both are known to have important roles in synchronizing reproductive physiology and behavior in salmonids as well as in other fish. El-Khateib and Afifi (1993) observed the same signs on Tilapia niloticus when it was exposed to Diazinon.

On contrast with the results reported in this study and in the previously mentioned studies, Scholz et al. (2000) reported that diazinon had no effect on swimming behavior or visually guided food capture on chinook salmon (Oncorhynchus tshawytscha) when treated with 0.1, 1.0 and 10.0 μg L-1. But in a partial agreement, they reported that Diazinon significantly inhibited olfactory-mediate alarm response at concentration as low as 1.0 μg L-1 in addition to a homing behavior that was impaired at 10.0 μg L-1. Parallel clinical signs were observed in fish after the exposure to other pesticides.

Effect of in vivo Sublethal Concentration of Diazinon on Total Protein Content in Blood and Muscles
Total protein content in both muscles and blood serum of the tested fish were significantly (p<0.05) reduced after been exposed to both of the tested sublethal concentrations of Diazinon (LC10 and LC33.5) for chronic exposures of 30 days compared with the control. Total protein in muscles and blood serum was significantly raised after fish were recovered for 7 days. Compared to the control group, total protein content in serum was reduced by 22.3% for LC10 and 24.3% for LC33.5. Both were increased in 7 days recovery to 10.64 and 4.86%, respectively. The same period caused reduction in muscle’s total protein content by 13.7% for LC10 and 21.9% for LC33.5. Both were increased in 7 days recovery to 4.41 and 9.42%, respectively. Results are shown in Table 4 and 5.

Table 4: Effect of sublethal concentrations of diazinon on total protein content in blood serum
Image for - Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)
Similar letter(s) indicate to non significant differences (p≥0.05), Different letter(s) indicate to significant differences (p≤0.05)

Table 5: Effect of sublethal concentrations of diazinon on protein content in muscles
Image for - Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)
Similar letter(s) indicate to non significant differences (p≥0.05), Different letter(s) indicate to significant differences (p≤0.05)

Table 6: Relative molecular weights and bands intensity of the SDS/PAGE separated proteins of muscles of tilapia treated with 1/10 LC50 of Diazinon
Image for - Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)
M.W.: Molecular weight (kDa), St.: Standard marker, CON.: Control fish, TRE.: Treated fish, REC.: Recovered fish

A similar result was reported by Luskova et al. (2002) evidences a significant decrease in protein concentration in blood serum of carp (Cyprinus carpio L.). Khalaf-Allah (1999) indicated that total protein was lower in fish exposed to 1/10 LC50 of diazinon compared to the non-exposed ones even though they were vaccinated before exposure to diazinon. Danasoury et al. (1997) demonstrated a decrease in muscle protein in acute and chronic exposure, they reported that in recovery condition the decrease was continued but with tendency to recovery. Sakr and Gabr (1992) reported that in some cases, diazinon exposure to fish caused changes in muscles.

Effect of Sublethal Concentration of Diazinon on Muscles’ Protein Banding Patterns
Analyzing the pictured stained SDS/PAGE gel by gel documentation system (GDS) indicated the presence of 21 bands in the control sample and 21 bands in the 1/10 LC50 treated and recovered fish Table 6. While 20 bands only were scanned in the 1/3 LC50 treated and recovered sample as shown in Table 7. Bands of 92.4, 61.16 and 25.00 kDa were induced in the 1/10 LC50 treated and recovered fish and were not scanned in the control sample. While in the 1/3 LC50 treatment, only bands of 92.4 and 25.00 kDa were induced in the treated and recovered samples and were not scanned in the control sample. Meanwhile, 99.76 and 26 kDa proteins were also induced in the treated and recovered fish, but they were scanned in thin bands in the control lanes.

The 52, 27 and 6.8 kDa proteins were not scanned in the treated and recovered samples in both treatments, which indicate that these proteins were probably highly affected by the stress caused by the treatment, which led to its high reduction. Also, 33.55, 31.72, 24.31 and 20.8 kDa proteins showed a slight reduction in both treatments. The rest of bands were all remarkably thinner in the treated sample and the recovered sample in both treatments, indicating to a reduction in the protein of these bands. Protein bands of the treated fish were obviously thinner than those in the recovered fish, which indicated that the proteins were highly reduced most likely due to the Diazinon treatment and that they were induced in the recovered fish after the poison was removed. The bands were reduced to nearly normal in the recovered fish in both treatments. The Induction of these proteins was most likely caused by the treatment which simulated the accumulation of existing proteins or synthesis of new proteins (Singh et al., 2002). The results presented in this research revealed that diazinon at concentration ranged from 13.7-21.5% significantly reduced the muscular protein in Nile tilapia fish.

Table 7: Relative molecular weights and bands intensity of the SDS / PAGE separated proteins of muscles of tilapia treated with 1/3 LC50 of Diazinon
Image for - Evaluation of Diazinon Toxicity on Nile Tilapia Fish (O. niloticus)
M.W.: Molecular weight (kDa), St.: Standard marker, CON.: Control fish, TRE.: Treated fish, REC.: Recovered fish

REFERENCES

1:  Abdel Fattah, N.A., 1992. Detection of Pesticide Residues in Market Fish. M.V. Sci. University, Cairo

2:  Allison, D.T. and R.O. Hermanutz, 1977. Toxicity of Diazinon to Brook Trout and Fathead Minnows. Research Series, Environmental Res. Lab., U.S. EPA., Duluth, MN

3:  Beauvais, S.L., S.B. Jones, S.K. Brewer and E.E. Little, 2000. Physiological measures of neurotoxicity of diazinon and malathion to larval rainbow trout (Oncorhynchus mykiss) and their correlation with behavorial measures. Environ. Toxicol. Chem., 19: 1875-1880.
CrossRef  |  

4:  Brown, E. and J. Gratzek, 1979. Maintainance and Improvement of Ponds. In: Fish Farming Handbook, Brown, E.E. and J.E. Gratzek (Eds.). AVI Publishing Company, Werport, Connecticut

5:  Danasoury, M.A.K., L.A. Reda, A. Shoukry and F. Kayomy, 1997. Some physiological effects of sublethal concentrations of Bayluscide and Malathion on Nile tilapia fish Oreochromis niloticus. Egypt. J. Applied Sci., 12: 10-30.

6:  Doving, K.B., 1991. Assessment of animal behaviour as a method to indicate environmental toxicity. Comp. Biochem. Physiol. C., 100: 247-252.
PubMed  |  

7:  El-Khateib, T. and S.H. Afifi, 1993. Inspection of (Tilapia nilotica) Nile fish exposed to organophosphorus compound (Diazinon). Assiut Vet. Med. J., 29: 119-124.
Direct Link  |  

8:  Finney, D.J., 1971. Probit Analysis. 3rd Edn., Cambridge University Press, London, UK., pp: 76-80
CrossRef  |  Direct Link  |  

9:  Fujii, Y. and S. Asaka, 1982. Metabolism of diazinon and diazoxon in fish liver preparations. Bull. Environ. Contamin. Toxicol., 29: 455-460.
CrossRef  |  

10:  Goodman, L.R., D.J. Hansen, D.L. Coppage, J.C. Moore and E. Mattews, 1979. Diazinon: Chronic toxicity and brain acetylcholinesterase inhibition in the sheepshead minnow, Cyprinodon variegates. Trans. Am. Fish., 108: 479-488.
CrossRef  |  

11:  Henry, R.J., 1964. Clinical Chemistry: Principles and Techniques. Harper and Row, New York

12:  Kamrin, M.A., 1997. Pesticide Profiles: Toxicity, Environmental Impact and Fate. CRC Press, Boca Raton, FL., USA., ISBN-13: 9781420049220, Pages: 704

13:  Keizer, J., G. D`Agostino, R. Nagel, T. Volpe, P. Gnemi and L. Vittozzi, 1995. Enzymological differences of AChE and diazinon hepatic metabolism: Correlation of invetro data with the selective toxicity of diazinon to fish species. Environ. Toxicol., 171: 213-220.
Direct Link  |  

14:  Khalaf-Allah, S.S., 1999. Effect of pesticide water pollution on some haematological, biochemical and immunological parameters in Tilapia nilotica fish. Dtsch Tierarztl Wochenschr, 106: 67-71.

15:  Laemmli, U.K., 1970. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature, 227: 680-685.
CrossRef  |  Direct Link  |  

16:  Luskova, V., M. Svoboda and J. Kolarova, 2002. The effect of diazinon on blood plasma biochemistry in carp (Cyprinus carpio L.). Acta Veterinaria Brno, 71: 117-123.
Direct Link  |  

17:  Moore, A. and C.P. Waring, 1998. Mechanistic effects of atriazine pesticide on reproductive endocrine function in mature male Atlantic salmon (Salmn salar L.) Parr. Pest Biochem. Physiol., 62: 41-50.
Direct Link  |  

18:  Novartis, 1997. An Ecological Risk Assessment of Diazinon in the Sacramento and San Joaquin River Basins. Technology Repopt, Novartis Crop Protection, Inc., Greensboro, NC

19:  NRC., 1993. Nutrient Requirements of Fish. National Academy Press, Washington, DC., USA., ISBN-13: 9780309048910, Pages: 114

20:  Rath, S. and B.N. Misra, 1981. Toxicological effects of dichlorvos (DDVP) on brain and liver acetylcholinesterase (AChE) activity of Tilapia mossambica, Peters. Toxicology, 19: 239-245.
CrossRef  |  PubMed  |  

21:  SAS., 1998. SAS User's Guide Statistics. 6th Edn., SAS Institute Inc., Cary, NC., USA

22:  Scholz, N.L., N.K. Truelove, B.L. French, B.A. Berejikian, T.P. Quinin, E. Casillas and T.K. Collier, 2000. Diazinon disrupts antipredatore and homing behaviours in Chinook salmon (Oncorhynchus tshawytscha). Can. J. Fish. Aquat. Sci., 57: 1911-1918.
Direct Link  |  

23:  Singh, M.S., K.P. Joy, V.S. Raj and I. Chowdhury, 2002. Testosterone-induced changes in protein profiles of seminal vesicle and testis in the catfish, Clarias batrachus: A SDS-PAGE study. J. Fish. Soc. Taiwan, 29: 107-116.

24:  Smit, G.L. and J. Hattingh, 1980. Hematological assessment of generally used fresh water fish blood anticoagulants. J. Fish Biol., 17: 337-341.
Direct Link  |  

25:  Svoboda, M., V. Luskova, J. Drastichova and V. Zlabek, 2001. The effect of diazinon on haematological indices of common carp (Cyprinus carpio L.). Acta Vet. Brno, 70: 457-465.
Direct Link  |  

26:  Tawfic, M.A., N. Loutfy and E. El-Shiekh, 2002. Residue levels of DDE and PCBs in the blood serum of women in the Port Said region of Egypt. J. Hazard. Mater., A89: 41-48.
Direct Link  |  

27:  Tsuda, T., T. Inoue, M. Kojima and S. Aoki, 1997. Pesticides in water and fish from rivers flowing into lake Biwa. Bull. Environ. Contamin. Toxicol., 57: 442-449.

28:  US EPA, US Environmental Protection Agency, 1995. Integrated Risk Information System. Environmental Protection Agency, Washington, DC

29:  Vaid, S. and L.M. Mishra, 1999. Recovery of diazinon and quinalphos induced toxicity in fish brain. Indian J. Environ. Health, 41: 126-129.
Direct Link  |  

30:  Abdelhamid, A.M., 2003. Fundamentals of Fish Production and Husbandry. Mansoura University Press, Egypt, ISBN: 9775526041, pp: 658

31:  Abdelhamid, A.M., 2005. Carcinogens. Darannshr, Cairo, Egypt, ISBN: 9773161498, pp: 241

32:  Sakr, S.A. and S.A. Gabr, 1992. Ultrastructural changes induced by diazinon and neopybuthrin in skeletal muscles of Tilapia nilotica. Bull. Environ. Contamin. Toxicol., 48: 467-473.
CrossRef  |  

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