scholarly journals ‘The Plastic Nile’: First Evidence of Microplastic Contamination in Fish from the Nile River (Cairo, Egypt)

Toxics ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 22 ◽  
Author(s):  
Farhan R. Khan ◽  
Yvonne Shashoua ◽  
Alex Crawford ◽  
Anna Drury ◽  
Kevin Sheppard ◽  
...  

The presence of microplastics (MPs) in the world’s longest river, the Nile River, has yet to be reported. This small-scale study aimed to provide the first information about MPs in the Nile River by sampling the digestive tracts of two fish species, the Nile tilapia (Oreochromis niloticus, n = 29) and catfish (Bagrus bayad, n = 14). Fish were purchased from local sellers in Cairo, and then their gastrointestinal tracts were dissected and examined for MPs. Over 75% of the fish sampled contained MPs in their digestive tract (MP prevalence of 75.9% and 78.6% for Nile tilapia and catfish, respectively). The most abundant MP type was fibers (65%), the next most abundant type was films (26.5%), and the remaining MPs were fragments. Polyethylene (PE), polyethylene terephthalate (PET) and polypropylene (PP) were all non-destructively identified by attenuated total reflectance Fourier transform infrared spectroscopy. A comparison with similar studies from marine and freshwater environments shows that this high level of MP ingestion is rarely found and that fish sampled from the Nile River in Cairo are potentially among the most in danger of consuming MPs worldwide. Further research needs to be conducted, but, in order to mitigate microplastic pollution in the Nile River, we must act now.

2021 ◽  
Vol 17 (2) ◽  
pp. 152-159
Author(s):  
Okechukwu Kenneth Wokeh ◽  
Ekinadose Orose

Human population has continued to increase unabatedly with its attendant demands on food in order to ease the difficulties of malnutrition and starvation. This continuous rise in population has clearly indicated that the conventional forms of livestock production and captured fisheries will not be sufficient to solve the problem of high protein demands. Aquaculture remains the best option that can bridge the wide gap between human protein demands and domestic production through the culture of fish species like Nile Tilapia (Oreochromis niloticus). Oreochromis niloticus is one of the most cultured finfish, due to its acceptability as food, fast growth, availability for farmers, ability to breed in captivity, resistance to diseases and harsh environmental conditions. Despite all these outstanding characteristics, there is still high level of apathy in commercial production of Nile Tilapia, due to its precocious maturity and uncontrolled breeding, which results in overpopulation of ponds, stunted growth and low commercial value. To mitigate this challenge, the use of synthetic hormones such as 17α-methyl testosterone has been developed to masculinize female tilapia present in a pond, thereby allowing the production of marketable sized fish since the male grows faster than the female. Though, the use of synthetic hormones has helped in some ways, but the negative effects have necessitated farmers to seek alternatives that are environmental friendly and safe for consumers. Dietary phytochemicals have been established to be good alternatives and their use is now gaining global acceptance. Dietary phytochemicals are bioactive compounds commonly found in plant-based diets such as fruits, vegetables, grains and teas. Dietary phytochemicals when administered to newly hatched tilapia species, influences the undifferentiated gonadal tissue of generic females to develop testicular tissue, thus functioning reproductively as males. Some of these phytochemicals such as Flavonoids, Saponins, Phenolics and Alkaloids are found in plants like Carica papaya seeds, Azadirachta indica, and Mucuna pruriens. The usefulness of these phytochemicals is based on their ability to influence sex reversal in Oreochromis niloticus, cost effect, easily accessible especially by small scale fish farmers, simple to apply, and being safe for both human and the environment since they are more biodegradable than synthetic hormones.


1993 ◽  
Vol 24 (2) ◽  
pp. 229-235
Author(s):  
G. C. MAIR ◽  
C. C. ESTABILLO ◽  
R. C. SEVILLEJA ◽  
R. D. RECOMETA

Author(s):  
Arne A Ratulangi ◽  
Reiny Tumbol ◽  
Hengky Manoppo ◽  
Henneke Pangkey

This study aims to apply vaccination against bacterial disease. The purpose of vaccination is to trigger the immune respone both non-specific and specific of fish against bacteria Motile Aeromonas Septicaemia (MAS) caused by Aeromonas hydrophila. The vaccination for fish with different ages: 2-3 weeks and 5 weeks were done using immersion method. The fish were re-vaccinated (booster) after two weeks of the first vaccination. The survival rate was < 50 % for juveniles 2-3 weeks and > 50% for juveniles 5 weeks. Survival rate for juveniles 5 weeks was higher than juveniles of 2-3 weeks. This shows that organs of juveniles of 5 weeks were more complete than the 2-3 weeks juveniles. The age of fish is one of the important factors for successfully vaccination. Penelitian ini bertujuan untuk melakukan penerapan vaksinasi terhadap penyakit bakterial. Vaksinasi ditujukan untuk merangsang respon kekebalan non- spesifik dan spesifik pada tubuh ikan terhadap penyakit Motile Aeromonas Septicaemia (MAS) yang disebabkan oleh bakteri Aeromonas hydrophila. Vaksin diberikan pada benih ikan nila yang berbeda umur yaitu 2-3 minggu dan 5 minggu dengan menggunakan metode perendaman. Ikan divaksinasi ulang (booster) setelah 2 (dua) minggu dari vaksinasi yang pertama. Prosentase kelangsungan hidup < 50 % untuk benih umur 2-3 minggu dan > 50% untuk benih umur 5 minggu. Jumlah kematian benih umur 2-3 minggu lebih tinggi dari 5 minggu. Hal ini menunjukkan bahwa fungsi organ benih umur 5 minggu telah lebih lengkap dari pada benih umur 2-3 minggu. Umur ikan merupakan salah satu faktor penting penentu keberhasilan suatu kegiatan vaksinasi.


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