Mortality in catfishes: A devastating threat to Bangladesh’s aquaculture

The farmers become bewildered seeing the devastating mortalities of fish in their ponds and they apply different veterinary drugs and antibiotics to control the mortality, but the total crop is damaged by only 7-10 days

Revamping in catfish production is glorified as one of the most successful advances in the aquaculture sector of Bangladesh. There are few high valued catfishes such as gulsha (Mystuscavasius), pabda (Ompokpabda), shing (Heteropneustesfossilis) and magur (Clariusbatrachus) are farmed profitably all over the country due to its simple culture technologies which is developed and guided by the Department of Fisheries (DoF), Bangladesh Fisheries Research Institute (BFRI) through their vast research activities. Meanwhile, few entrepreneur and private organizations have made the technology commercially viable by importing micro feeds and other necessary technologies. As a result, the production of these consumer demanded fishes has increased almost 75,000 metric ton during the last production year 2019-2020.

The nutritive value of these particular four species is abundant in containing protein, lipids, ash, minerals and vitamins. We consume the amount of nutrition by in taking 100g edible weight of pabda, gulsha, shing and magur are Protein: 16.2 g, 16.8 g, 19.1 g and 16.6 g; Fat: 9.5 g, 5.1 g, 1.9 g and 1.3 g; Ash: 0.9 g, 1.0 g, 1.0 g and 1.1 g; Energy: 619 kj, 479 kj, 374 kj and 326 kj, respectively. The catfishes are enjoyed appetizingly by the all classes of people as a delicious food item by cooking with a variety of savoury and tasty recipes. These species are recommended by the dieticians and nutritionists to the surgery patients due to containing the high amount of poly unsaturated fatty acids (PUFA) and other tissue building essential amino acids.

This nutrition value is collected from a research conducted in Asure Quality Laboratory, New Zealand and Technical University of Denmark, which is published in the Journal of Food Composition and AnalysisV-42, page 120–133in 2015. The research team also found the following macro and micro mineral stuffs on their study on total 54 fish and shrimp species of Bangladesh:

Species	Iron (mg)	Zinc (mg)	Calcium (mg)	Iodine (µg)	Selenium (µg)	Phosphorus (mg)
Pabda	0.46	0.90	91.0	7.0	27.0	150.0
Gulsha	1.80	1.30	120.0	13.0	41.0	180.0
Shing	2.20	1.10	60.0	nd	31.0	220.0
Magur	1.20	0.74	59.0	22.0	22.0	210.0
Species	Magnesium (mg)	Sodium (mg)	Potassium (mg)	Manganese (mg)	Sulphur (mg)	Copper (mg)
Pabda	23.0	47.0	230.0	0.073	190.0	0.042
Gulsha	26.0	33.0	210.0	0.22	220.0	0.039
Shing	37.0	54.0	300.0	0.038	230.0	0.057
Magur	26.0	61.0	350.0	0.021	180.0	0.050

But, unfortunately a huge number of severe mortalities incurred and destroyed the production by some unidentified diseases in the culture ponds of catfishes. Every year thousand tons of gulsha, pabda, shing and magur production is hampered by the pathogenic outbreaks in the farms. As a result, the farmers are losing their investment and interest to the catfish farming, which is considered as a great threat to the diversified aquaculture practice of Bangladesh.

As an aquaculturist, personally I do visit throughout the country for ensuring technical guidance and consultation at the farming level. I observe, since 2015 the mortality in catfish ponds is becoming out of control day by day even the farmers are taking some preventive measures. The farmers become bewildered seeing the devastating mortalities of fish in their ponds and they apply different veterinary drugs and antibiotics to control the mortality, but the total crop is damaged by only 7-10 days.

There are several types of clinical symptoms found during the distressing mortality. Most of the cases, different kinds and sizes of ulcers, lesion, distensions, hemorrhage are found on the ventral, lateral and dorsal portion of the body. The affected fishes lose their appetite, become lethargic, go to coma and finally the fishes died drastically. The farmers use a lot of immune modulator, disinfectants, probiotics even antibiotics in to their culture ponds. But the output is negligible to the farmers.  The situation is getting dangerous to farmers as well as the environmental degradation.

It is high time to take some initiatives against the fatal disease of catfishes as well as to other fin fishes and shrimps. So far, we know there are few public universities where fish parasitology is studied to the graduate students as a fundamental course under the Fisheries department. I would request to the fish pathology experts of the universities to conduct some laboratory-based comprehensive research on the contemporary disease prevailing pathogen identification and their solution optimization. I also seek attention to the international research organization World Fish for carrying out some experiments for disease identification and treatment optimization. In this regard, I would say that there is a few conventional PCR laboratories in Khulna region those are operated by government and non-governmental organizations.

Moreover, there is also a Real-Time PCR based molecular laboratory (Fishtech laboratory) in Khulna which is operated by a private company limited. Currently it tests probe and primer based11 types of viral and bacterial pathogens,15 types of bacteriological tests and 18 types of water and soil quality parameters. It is BIOSAFTEY LEVEL-II category, Real-Time PCR brand is CFX96 BIO-RAD PCR detection system, USA.

In fine, I would say the concerned actors of this industry should take initiatives to conduct research and experiments to find out the proper solution to preserve these exportable small indigenous fish species of Bangladesh, which will save the farmers as well as fish biodiversity of Bangladesh.

The writer is an aquaculturist. Email: [email protected]

Mortality in catfishes: A devastating threat to Bangladeshs aquaculture

The farmers become bewildered seeing the devastating mortalities of fish in their ponds and they apply different veterinary drugs and antibiotics to control the mortality, but the total crop is damaged by only 7-10 days

Revamping in catfish production is glorified as one of the most successful advances in the aquaculture sector of Bangladesh. There are few high valued catfishes such as gulsha (Mystuscavasius), pabda (Ompokpabda), shing (Heteropneustesfossilis) and magur (Clariusbatrachus) are farmed profitably all over the country due to its simple culture technologies which is developed and guided by the Department of Fisheries (DoF), Bangladesh Fisheries Research Institute (BFRI) through their vast research activities. Meanwhile, few entrepreneur and private organizations have made the technology commercially viable by importing micro feeds and other necessary technologies. As a result, the production of these consumer demanded fishes has increased almost 75,000 metric ton during the last production year 2019-2020. The nutritive value of these particular four species is abundant in containing protein, lipids, ash, minerals and vitamins. We consume the amount of nutrition by in taking 100g edible weight of pabda, gulsha, shing and magur are Protein: 16.2 g, 16.8 g, 19.1 g and 16.6 g; Fat: 9.5 g, 5.1 g, 1.9 g and 1.3 g; Ash: 0.9 g, 1.0 g, 1.0 g and 1.1 g; Energy: 619 kj, 479 kj, 374 kj and 326 kj, respectively. The catfishes are enjoyed appetizingly by the all classes of people as a delicious food item by cooking with a variety of savoury and tasty recipes. These species are recommended by the dieticians and nutritionists to the surgery patients due to containing the high amount of poly unsaturated fatty acids (PUFA) and other tissue building essential amino acids. This nutrition value is collected from a research conducted in Asure Quality Laboratory, New Zealand and Technical University of Denmark, which is published in the Journal of Food Composition and AnalysisV-42, page 120133in 2015. The research team also found the following macro and micro mineral stuffs on their study on total 54 fish and shrimp species of Bangladesh: Species Iron (mg) Zinc (mg) Calcium (mg) Iodine (g) Selenium (g) Phosphorus (mg) Pabda 0.46 0.90 91.0 7.0 27.0 150.0 Gulsha 1.80 1.30 120.0 13.0 41.0 180.0 Shing 2.20 1.10 60.0 nd 31.0 220.0 Magur 1.20 0.74 59.0 22.0 22.0 210.0 Species Magnesium (mg) Sodium (mg) Potassium (mg) Manganese (mg) Sulphur (mg) Copper (mg) Pabda 23.0 47.0 230.0 0.073 190.0 0.042 Gulsha 26.0 33.0 210.0 0.22 220.0 0.039 Shing 37.0 54.0 300.0 0.038 230.0 0.057 Magur 26.0 61.0 350.0 0.021 180.0 0.050 But, unfortunately a huge number of severe mortalities incurred and destroyed the production by some unidentified diseases in the culture ponds of catfishes. Every year thousand tons of gulsha, pabda, shing and magur production is hampered by the pathogenic outbreaks in the farms. As a result, the farmers are losing their investment and interest to the catfish farming, which is considered as a great threat to the diversified aquaculture practice of Bangladesh. As an aquaculturist, personally I do visit throughout the country for ensuring technical guidance and consultation at the farming level. I observe, since 2015 the mortality in catfish ponds is becoming out of control day by day even the farmers are taking some preventive measures. The farmers become bewildered seeing the devastating mortalities of fish in their ponds and they apply different veterinary drugs and antibiotics to control the mortality, but the total crop is damaged by only 7-10 days. There are several types of clinical symptoms found during the distressing mortality. Most of the cases, different kinds and sizes of ulcers, lesion, distensions, hemorrhage are found on the ventral, lateral and dorsal portion of the body. The affected fishes lose their appetite, become lethargic, go to coma and finally the fishes died drastically. The farmers use a lot of immune modulator, disinfectants, probiotics even antibiotics in to their culture ponds. But the output is negligible to the farmers. The situation is getting dangerous to farmers as well as the environmental degradation. It is high time to take some initiatives against the fatal disease of catfishes as well as to other fin fishes and shrimps. So far, we know there are few public universities where fish parasitology is studied to the graduate students as a fundamental course under the Fisheries department. I would request to the fish pathology experts of the universities to conduct some laboratory-based comprehensive research on the contemporary disease prevailing pathogen identification and their solution optimization. I also seek attention to the international research organization World Fish for carrying out some experiments for disease identification and treatment optimization. In this regard, I would say that there is a few conventional PCR laboratories in Khulna region those are operated by government and non-governmental organizations. Moreover, there is also a Real-Time PCR based molecular laboratory (Fishtech laboratory) in Khulna which is operated by a private company limited. Currently it tests probe and primer based11 types of viral and bacterial pathogens,15 types of bacteriological tests and 18 types of water and soil quality parameters. It is BIOSAFTEY LEVEL-II category, Real-Time PCR brand is CFX96 BIO-RAD PCR detection system, USA. In fine, I would say the concerned actors of this industry should take initiatives to conduct research and experiments to find out the proper solution to preserve these exportable small indigenous fish species of Bangladesh, which will save the farmers as well as fish biodiversity of Bangladesh. The writer is an aquaculturist. Email: [email protected]