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Monthly changes in physico-chemical water quality parameters of a rain fed Nath Sagar reservoir at Paithan, Aurangabad district, Maharashtra, India were investigated to assess the suitability of this reservoir for fish and fisheries practices. The different physico-chemical parameters viz., temperature, dissolved oxygen, pH, total alkalinity, chloride, hardness, calcium, magnesium, nitrite and phosphate were carried out for a period of one year beginning from July 2013 to June 2014. Various physico-chemical parameters determined revealed that the seasonal fluctuations in water temperature, dissolved oxygen, pH, total alkalinity, hardness and nitrite in all the seasons were within the desirable limits for fish and fisheries practices. However, low level of chloride, calcium and magnesium and high level of phosphate during all the seasons were recorded. These parameters need to be modifying in order to favour fish culture. [ABSTRACT FROM AUTHOR]

The crop production in the district of Kasaragod in Kerala State (India) is characterized by low input-low yield concept and rain-fed agriculture. A field study was conducted in Western Ghat region of the district to develop a suitable rainwater harvesting system adoptable to hilly terrains and to test its efficacy for improving the use efficiency of the harvested water by its multiple uses. The cost-benefit analysis of the water harvesting system was also carried out to find out its affordability to farmers. The water harvesting system has been developed by integrating three components: (i) improving the productivity of coconut and component crops in the cropping units (ii) developing multiple water use systems, and (iii) the conjunctive use of the harvested water along with other surface and groundwater resources. Based on the estimated annual costs and returns, the Benefit -Cost ratio was found to be 1.69 and all other financial viability criteria (IRR and NPV) were also found favourable for investment on a lined water harvesting tank integrated with a micro-irrigation system and fish farming. The study suggested that the rainwater harvesting could be implemented as a viable alternative to conventional water supply or on-farm irrigation projects considering the fact that any land anywhere can be used to harvest rainwater. Further, the water use efficiency can be improved through effective harvesting and subsequent multiple uses of stored water. [ABSTRACT FROM AUTHOR]

Efficacy of in-feed administration of emamectin benzoate (EMB) was evaluated in commercial culture farms of Asian seabass (Lates calcarifer), grey mullet (Mugil cephalus), pearlspot (Etroplus suratensis), Indian major carp (Labeo rohita), goldfish (Carassius auratus) and koi carp (Cyprinus rubrofuscus) in different parts of India. Fish naturally infested with Caligus minimus , Argulus quadristriatus , Argulus siamensis , Lernanthropsis mugilii and Lernaea cyprinacea were administered medicated feed for 7–10 consecutive days (@ 50 μg kg−1 body weight day−1). Efficacy of the treatment was monitored by recording the parasitic intensity (PI). The study revealed PI was zero on head and gills within four days while parasites remained on trunk and fins till six days both in seabass and pearlspot. However, zero PI was achieved on 6th day on head and gills, and on 8th day on trunk and fins in seabass and Indian major carp. Treatment with EMB for seven days was effective against C. minimus , A. quadristriatus , A. siamensis and L. mugilii in E. suratensis , L. calcarifer, L. rohita and M. cephalus , respectively while L. cyprinacea infestation in seabass, goldfish and koi carp needed an extended treatment up to 10 days. In all the cases no recurrence was observed for 60 days post medication. Study revealed that there is a need for integrated pest management (IPM) program for effective prevention and control of parasitic infestation in commercially important food and ornamental fish cultures. • Efficacy of emamectin benzoate was determined in parasite infected fish species reared in different culture systems. • The efficacy was 100% against Argulus spp., Caligus spp. and Lernanthropsis spp. on 7th day, and against Lernaea spp. following 7 days treatment. • Administration for 10 days was required for the control of Lernaea spp. • No re-infestation of parasites was observed for a period of 60 days post medication. [ABSTRACT FROM AUTHOR]

The use of immunostimulants as an alternative to the drugs, chemicals and antibiotics currently being used to control fish diseases in fish culture is attracting the attention of many researchers. In this context, many have focused on the use of medicinal plant products as potential therapeutic measures for modulating the immune response and, specifically, on the use of herbs to prevent and control fish diseases. Medicinal plants (plant remedies) are a deeply rooted component of the cultural heritage of many people from diverse cultures and countries and are, as such, closely linked to the maintenance of good health. The aim of this paper is to review research currently being carried out on the herbs and herbal extracts that have been shown to modulate the immune system of fish. Special attention is given to the use of Chinese and Indian herbs. [ABSTRACT FROM AUTHOR]

Human urine (HU) is a biogenic fertilizer which has raised immense interest owing to its capacity of combining sanitation and nutrient recovery. In search of an alternative organic fertilizer for fish culture, the nutrient potential of HU was evaluated. Fries of Indian carps and larvae of freshwater prawn were reared for 120 days under six conditions: (a) aerated and (b) non-aerated fresh HU (0.01%), (c) cattle manure (CM; 1.8 kg tank -1 ), mixed treatment with CM and HU under (d) iso-phosphorus and (e) iso-nitrogenous condition and (f) control. Monitoring of water quality and biological parameters revealed that total fish yield was the highest in CM (621.5 g tank -1 ) followed by mixed treatments under iso-nitrogenous (428 g tank -1 ) and iso-phosphorus (333 g tank -1 ) conditions, aerated HU (321 g tank -1 ) and HU (319 g tank -1 ). The gross primary productivity (GPP) in HU was satisfactory (601.8 mg C m -2  h -1 ) and superior to all but CM treatment. The abundance of heterotrophic bacteria (HB) was highest in CM and lowest in HU. Both GPP and HB population were correlated positively with fish yield per tank. Although pH in all treatments remained high (pH 8.4-8.9), no ammonia toxicity was observed. No E. coli infestation in any fish muscle was encountered. The concentrations of cadmium and lead in fish muscle were within respective safe level. The study established that high fertilizer potential of HU could be exploited as an alternative organic fertilizer or as a candidate to be blended with cattle manure.