Probiotics in Brackish Water Fish Farming: A Special Focus on Encapsulated Probiotics

In GMOs' age, pesticides, contaminants, and other anthropogenic practices move towards an environmentally sustainable solution. Aquaculture is one of the fastest-growing food sources connected with several challenges. Aquaculture industries are required to produce food with a better state of health and environmentally friendly. The encapsulation of probiotics in the aquatic feed addresses various problems as many probiotic organisms are shown to strengthen immunity, improve growth, survival, and reproduction of many fish species, including brackish water fish. By including certain probiotics as a food additive, the well-being of aquatic organisms can be enhanced. This review summarizes probiotics' inclusion in an encapsulated form in aquatic feed formulation for enhancing brackish water fish culture.

First confirmed record of an established population of green swordtail (Xiphophorus hellerii Heckel, 1848) in Europe

The green swordtail (Xiphophorus hellerii) is a freshwater and brackish water fish native to North and Central America. It experiences wide human-traced introduction around the world, mostly due to aquarium release. Individuals of the green swordtail population from the warm spring with artificial origin located in Asparuhovo district, Bulgaria, were collected. The invasiveness screening tool for non-native freshwater fishes (FISK v2) calibrated for the Balkan region was used to assess potential invasion risk of the green swordtail to the coastal freshwater bodies of the Eastern Balkans. This study is the first confirmation on an existing self-sustained population of X. hellerii in Bulgaria and respectively in Europe. Climate change and the trend of warmer winters are prerequisites for the acclimatization of this species to the temperature out of the studied thermal spring. Therefore, the potential of the green swordtail to colonise new habitats is increasing with such facilitated acclimatization. We conclude that the green swordtail poses a high risk to become the next new invasive species in Southern Europe.

Crop rotation with penaeid shrimp (Penaeus monodon).

In crop rotation different crops may be cultivated within the same year to rejuvenate the environment and reduce pests and diseases. Crop rotation in shrimp farming is not popular in Bangladesh as the shrimp bagda (Penaeus monodon) is much more profitable than growing rice or farming brackish water fish. In traditional and improved traditional farms, it is usual practice to stock seed and harvest shrimp year-round. Viral disease occurred in the 1990s and caused mass mortality of penaeid shrimp. To minimise the risk of disease, there is a need to apply crop rotation techniques of shrimp with rice and finfish on farms in coastal areas, as is carried out by some farmers. Shrimp culture is generally done in the dry season (February-June) when water salinity increases (>10ppt) and ceases in the rainy season (July-August) when salinity decreases (<5ppt) because of heavy rainfall. Depending on salinity, some farmers produce two crops. During February-June they produce shrimp and subsequently they produce rice or freshwater fish.

Penyuluhan Teknologi Pembenihan Ikan Bandeng Untuk Mendorong Kemandirian Produksi Benih Ikan Bandeng Di Kabupaten Bima Provinsi Nusa Tenggara Barat

Milkfish (Chanos chanos Forskal) is one of the high economic value of brackish water fish and it has become the main commodity of brackish water fisheries for Bima Regency. Bima Bay was the center of milkfish production in Bima Regency with a pond area of around 1,612.16 Ha. Fishponds were spread in 3 (three) districts, namely Bolo sub-district covering 759.95 Ha, Woha sub-district covering 765.82 Ha, and Palibelo sub-district covering 86.39 Ha. As many as 11.41% of the total area of ponds used for milkfish enlargement throughout the year, while 88.59% used for milkfish enlargement and salt production alternately. The area of a pond was about 0.25-0.65 Ha using a stocking density of 4.000-6.000 milkfish fry/pond. The number of seeds needed for the Bima bay area was around 27.4 million per year. Even though milkfish hatchery technology has developed, the technology is not yet understood by milkfish farmers. Therefore, extension activities need to be carried out with the aim of increasing public understanding of seedling and quality of seedlings produced so that the independence of seed production in the future can be realized. Aquaculture Study Program of Vocational Program at Bima Regency of Mataram University conducted a counseling activity in Bima Regency in September 2019 with the theme is Milkfish Hatchery (Chanos chanos Forskal) Household Scale, Opportunities and Problems. It was attended by about 40 target communities, namely Milkfish Farmers in the Bima Bay area. Based on communication during counseling, there needs to be a demonstration plot for Milkfish Hatchery in Bima Regency as a place for training and learning related communities

Levels of Organochlorine Pesticides in Brackish Water Fish from Niger River, Nigeria

Investigation of the levels of organochlorine pesticides (OCPs) in fish samples was carried out to assess the contamination status of Niger River. Ten different brackish water species of fish (6 samples for each, making a total of 60) were purchased from landing sites at the Delta area of Niger River. These were Drapane africana, Mochokus niloticus, Chrysichthys nigrodigitatus, Pristipoma jubelini, Vomer septapinis, Pseudotolithus senegalensis, Mugil cephalus, Pseudotolithus elongatus, Sphyraena piscatorum, and Lutjanus goreensis. OCPs were determined using standard methods. Certified reference standards from Accustandard USA were used for the instrument calibration and quantification of OCPs. Twenty OCPs, namely, α-HCH, β-HCH, γ-HCH, δ-HCH, endrin, endrin aldehyde, endrin ketone, heptachlor, heptachlor epoxide, aldrin, dieldrin, endosulfan I, endosulfan II, endosulfan sulfate, methoxychlor, α-chlordane, γ-chlordane, DDE, DDT, and DDT, were identified/quantified using Gas Chromatography (GC) (Hewlett Packard GC 5890 series 11 with electron capture detector). Confirmation was done using Shimadzu GCMS QP2010. The highest concentration of ∑OCPs in the brackish fish samples of the Niger River, 4302±2066 µg/kg fresh weight, with a range of 2237-6368 µg/kg, was detected in Drapane africana, while the lowest concentration, 2320±876.4, with a range of 1006-3288 µg/kg, was found in Mochokus niloticus. The concentration of total OCP compounds varied markedly amongst the different fish species. The guideline value of 2000 µg/kg fresh weight by WHO/FAO was exceeded and therefore implied potential harmful effects on humans. Since contamination of the fish samples was an indication of contamination of the river, the quality of the water for public water supply should be of concern; and therefore further monitoring is suggested.

Polychlorinated Biphenyls in Brackish Water Fish in the River Niger, Nigeria

Background. Anthropogenic polychlorinated biphenyls (PCBs) in aquatic environments poses human and ecological health risks in Nigeria. Objectives . This study determined the concentrations of PCBs in brackish water fish in the River Niger to assess the contamination status of fish consumed by the local population. Methods . The sampled fish species included Drepane africana, Mochokus niloticus, Chrysichthys nigrodigitatus, Pristipoma jubelini, Vomer septapinis, Pseudotolithus senegalensis, Mugil cephalus, Pseudotolithus elongatus, Sphyraena piscatorum and Lutjanus goreensis, purchased from landing sites. Six fish from each species were sampled, for a total of 60 samples. Twenty-seven (27) PCB congeners, #8, #18 #28, #44, #52, #60, #77, #81, #101, #105, #114, #118, #123, #126, #128, #138, #153, #156, #157, #167, #169, #170, #180, #185, #189, #195, and #206 were screened in the fish samples using standard methods. The PCBs were identified and quantified using gas chromatography (GC) (Hewlett Packard GC 5890 series 11 with electron capture detector). Confirmation was performed using Shimadzu GCMS QP2010. Results. The sum of the National Oceanic and Atmospheric Administration Agency (ΣNOAA) PCBs occurred at the highest concentration of 1830.0±484.0 μg/kg detected in Vomer septapinis, and the lowest in Pseudotolithus senegalensis, with a mean concentration of 795±169.3 μg/kg. The concentration of dioxin-like (DL) PCBs was highest in Pristipoma jubelini (992.0±88.6 μg/kg) and lowest (285.6±81.5 μg/kg) in Drepane africana. The highest mean concentration (418.±177.6 μg/kg) of International Council for the Exploration of the Seas-7 (ICES-7) PCBs was observed in Vomer septapinis. The heavier ICES-7 congeners PCB-138, PCB-153, and PCB-180 occurred at higher concentrations compared to the lighter molecular weight ICES-7: PCB-28, PCB-52, and PCB-101. The European Union (EU) marker PCB limit of 335 μg/kg was exceeded in all the brackish water fishes with the exception of Mochokus niloticus, Pristipoma jubelini and Pseudotolithus senegalensis. Discussion . The total level of PCBs in the brackish fish samples was relatively high at &gt;1000 μg/kg (above the World Health Organization (WHO) and Food and Agriculture Organization of the United Nations (FAO) guideline of 1000 μg/kg fresh weight). The EU guideline value for fish (220 μg/kg fresh weight) was exceeded in about 80% of the brackish fish samples studied. Conclusions. Consumption of fish from the River Niger may expose humans to polychlorinated biphenyls. In addition, since contamination of the fish samples is an indication of river contamination, river water quality is of great concern and there is a need for additional PCB data on water quality to be distributed to the community, followed by mitigation measures. Competing interests. The authors declare no competing financial interests.