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Simple Summary: Aquaculture suffers from losses due to disease outbreaks, and to keep the industry sustainable, there are strict limitations on antibiotic use. Therefore, several alternatives have been suggested, such as probiotics. Bacillus and Lactobacillus species are among the most studied and advised probiotics for aquaculture. However, researchers are now looking for other probiotic bacteria that can be used in aquaculture. In this context, non-lactic acid bacteria (non-LAB), which are mainly host-associated, should have promising effects on fish and shellfish. Given the potential and advantages of this kind of probiotics, the present review paper provides detailed information on the use of various non-LAB bacteria and provides a roadmap to future studies on new probiotics for sustainable aquaculture. With the intensification of aquaculture to meet the rising demands of fish and shellfish, disease outbreaks during the larval and adult stages are a major challenge faced by aqua culturists. As the prophylactic use of vaccines and antibiotics has several limitations, research is now focused on sustainable alternatives to vaccines and antibiotics, e.g., medicinal plants, probiotics, postbiotics, prebiotics, and synbiotics, as promising candidates to strengthen the immune response of fish and shellfish and to control disease outbreaks. With respect to probiotics, numerous studies are available revealing their health-promoting and beneficial impacts in aquaculture. However, most studies focus on Bacillus and Lactobacillus species. Keeping in view the positive effects of probiotic lactic acid bacteria in aquaculture, researchers are now looking for other probiotic bacteria that can be used in aquaculture. Recently, many non-lactic acid bacteria (non-LAB), which are mainly host-associated, have been reported to reveal beneficial effects in fish and shellfish aquaculture. The main non-LAB probiotic genera are Bifidobacterium, Clostridium, Microbacterium, Micrococcus, Paenibacillus, Acinetobacter, Alcaligenes, Enterobacter, Phaeobacter Pseudoalteromonas, Pseudomonas, Pseudomonas, and Vibrio. Despite the promising effects of non-LAB probiotics, comparably, there is limited available information in this context. This review focuses only on probiotic strains that are non-LAB, mostly isolated from the host digestive tract or rearing water, and discusses their beneficial effects in fish and shellfish aquaculture. This review will provide detailed information on the use of various non-LAB bacteria and provide a roadmap to future studies on new probiotics for sustainable aquaculture. [ABSTRACT FROM AUTHOR]

Simple Summary: In recent decades, trade of ornamental fish has significantly increased. A rise in demand was observed, especially from top importing countries that contributed majorly to the growth of the market. The destructive fishing methods caused a severe impairment of natural and environmental resources. Thus, there is a need to improve ornamental fish aquaculture, increasing the number of cultured species and limiting wild fish handling and transport stress losses. In this light, the use of microbial feed additives such as probiotics, prebiotics, and synbiotics, could help in improving the immune system and growth as well as increasing reproductive performance in captivity-bred species. Ornamental fish trade represents an important economic sector with an export turnover that reached approximately 5 billion US dollars in 2018. Despite its high economic importance, this sector does not receive much attention. Ornamental fish husbandry still faces many challenges and losses caused by transport stress and handling and outbreak of diseases are still to be improved. This review will provide insights on ornamental fish diseases along with the measures used to avoid or limit their onset. Moreover, this review will discuss the role of different natural and sustainable microbial feed additives, particularly probiotics, prebiotics, and synbiotics on the health, reduction in transport stress, growth, and reproduction of farmed ornamental fish. Most importantly, this review aims to fill the informational gaps existing in advanced and sustainable practices in the ornamental fish production. [ABSTRACT FROM AUTHOR]

Simple Summary: Stress-related losses are of major concern in aquaculture practices. Black seed is a medicinal plant species widely used as natural antioxidants and hepatic-nephric protector. Rohu is a commercially valuable culturable fish species. The present study was undertaken to assess the effects of dietary black seeds on the growth performance and antioxidant status of rohu. Fingerlings were fed on diets containing 0.0%, 1.0% and 2.5% black seed for 28 days. The results showed that rohu fed on black seed supplemented diets has increased growth rate. Moreover, black seed supplementation improved the muscles protein contents and antioxidant status as indicated by decreased lipid peroxidation and increased antioxidant enzymes levels in the liver, kidney, gills and brain of rohu. The black seed fed rohu showed decreased hepatic–nephric marker key-functioning marker enzymes levels. The histo-architecture of liver and kidney remained unchanged following black seed supplementation. Black seed is cheap and locally available in Pakistan. On the basis of the present study results, 2.5% black seed supplementation is suggested in rohu diet to increase its growth and avoid oxidative stress related losses. The results of the present study will be useful for nutritionists, aquaculturists and researchers in formulating aqua feeds. This feeding trial was conducted to investigate the effects of dietary black seed (Nigella sativa) supplementation on the growth performance, muscles proximate composition, antioxidant and histo-biochemical parameters of rohu (Labeo rohita). Fingerlings (8.503 ± 0.009 g) were fed on 0.0%, 1% and 2.5% black seed supplemented diets for 28 days. Fish sampling was done on the 7th, 14th, 21st and 28th day of experiment. The results of the present study indicated that black seed supplementation significantly increased growth performance and muscles protein contents of rohu over un-supplemented ones. Lipid peroxidation levels significantly decreased in all the studied tissues (liver, gills, kidney and brain) of black seed fed rohu, whereas the antioxidant enzymes (catalase, glutathione-S-transferase, glutathione peroxidase and reduced glutathione) activities were increased in all the studied tissues of black seed supplemented rohu at each sampling day. The hepatic-nephric marker enzymes levels were decreased for black seed fed rohu. The present study showed that tested black seed levels are safe for rohu. Black seed is cheaply available in local markets of Pakistan; therefore, based on the results of the present study, it is suggested that black seed has potential to be used as natural growth promoter and antioxidant in the diet of rohu. [ABSTRACT FROM AUTHOR]