Assessment of Fish Farming Practices, Operations, Water Resource Management and Profitability in Katsina State, Nigeria

This study assessed the fish production, culture facilities, operations, water resource management and profitability of fish farming in Katsina State, Nigeria, with a view of understanding the status of aquaculture development in Katsina State. Data were collected using structured questionnaire administered to 35 out of the active 42 farms in Katsina State at the period and the data obtained were analyzed using descriptive statistics and linear regression. Among the respondents, 37.1% used concrete tank alone and another 37.2% used concrete tank with other types of culture facilities, 57.1% practised mono-culture techniques and 77.1% used stagnant renewal system as culture system. Management of water quality was done by majority(82.9%) with mere visual evaluation, while 68.6% did not use any forms of water treatment. Most of the farms(80%) depended on imported feed for feeding their fish and gross profits of ■7.29±1.81 and ■157.83±118.08 were obtained on fingerlings and adult fish, respectively. The tested explanatory variables were responsible for 45.4% change in profitability and profitability was found to be dependent on feeding cost(t=–3.38 and p=0.002) and size of fish at harvest(t=2.70 and p=0.011). The research findings established that fish farming in Katsina State was under developed.

Aflatoxin Contamination and Rancidity in Locally Processed Commercial Fish Feeds and Ingredients along the Value Chain in Wakiso and Kampala Districts, Uganda

Aflatoxin contamination and rancidity in locally processed commercial fish feeds and ingredients along value chains is a Public and Animal health hazard. The study established the level of aflatoxin contamination, peroxide value (PV), Anisidine value (AnV), and their associated factors at storage areas among farmers, processors, traders, factories, and landing sites in the Wakiso and Kampala districts. The value chain actors were purposively selected in a cross-sectional study based on access to the feed store and the use of locally processed commercial fish feeds on farms. Data collected were statistically analyzed in SPSS version 20. All the samples (45) were positive for aflatoxin contamination and PV with 51% (23/45) of samples being contaminated with “above acceptable” aflatoxin levels and 66.6% (30/45) of samples with “above acceptable” PV. The overall percentage of “above acceptable” AnV was 11/29 (37.9%). Samples from factories were within acceptable contamination levels. Multivariate logistic regression analysis revealed no significant difference between aflatoxin contamination, peroxide, and Anisidine value with storage factors for locally processed commercial fish feeds and ingredients. The study recommended the purchase of fish feeds from factories and a larger study on storage factors responsible for aflatoxin contamination and rancidity in fish feeds in Uganda.

Cost of Production at Business Unit in Aquaculture Industry： Study at Aquafarm Nusantara Company

Types of industry are manifold, patterns used in the determination of the cost of production can also vary. Elements of the cost of production are raw materials, direct labor, and factory overhead. Value of raw materials used in aquaculture industry in particular needs to calculate the cost of feed consumed by fish, thus greatly affect the price of fish feed cost of production. The calculation of the value of raw materials in fish production cost element to consider is the calculation of the value of raw material components, namely, （1） biomass of harvestable fish as the basic multiplication cost of production per kilogram or per fish harvested fish; （2） the ratio of fish feed intake by the amount of fish produced or often called the Feed Conversion Ratio （FCR）; and （3） the average purchase price of feed on fish harvest period is used as the basis for calculating the cost of production as well. This research is applied research that uses data archive aquaculture companies. The results in the observed period, the value FCR is 0.80, which means to fish have been consumed as much as 0.80 kg of fish feed. Biomass of fish that are harvested at 47,399.95 kg or 1,869,647 individuals. The average purchase price of fish feed on the observation period amounted to IDR 4,855.79. So the price of raw materials contained in harvested fish in the observation period calculates the value of multiplying all the components of raw materials （i.e., IDR 184,131,362.57）. Method of calculating the cost of production companies is process method and charging method used is the full costing method.

Application of enzymes as a feed additive in aquaculture

Modern aquaculture must be sustainable in terms of energy consumption, raw materials used, and environmental impact, so alternatives are needed to replace fish feed with other raw materials. Enzyme use in the agri-food industry is based on their efficiency, safety, and protection of the environment, which aligns with the requirements of a resource-saving production system. Enzyme supplementation in fish feed can improve digestibility and absorption of both plant- and animal-derived ingredients, increasing the growth parameters of aquacultural animals. Herein we summarized the recent literature that reported the use of digestive enzymes (amylases, lipases, proteases, cellulases, and hemicellulases) and non-digestive enzymes (phytases, glucose oxidase, and lysozyme) in fish feed. In addition, we analyzed how critical steps of the pelleting process, including microencapsulation and immobilization, can interfere with enzyme activity in the final fish feed product.