The use of tunicate (Ciona intestinalis) as a sustainable protein source in fish feed – effects on the extrusion process, physical pellet quality and microstructure

The present study was conducted for two months between November 2019 and December 2019 to investigate the growth performance of Nile Tilapia fed with diets containing soyabean 100% (T1), soyabean and Achatina fulica: 50/50% (T2) and A. fulica 100% (T3). The experimental diets were formulated with 45% crude protein content. The stocking density was 30 fingerlings per tank of size 1m*1m*0.8m with three replications for each treatment. The tanks were stocked with the fingerlings of uniform size 9 ± 677 cm and weight 24 ± 0.66g. The experimental fishes were fed twice a day at 5% of their body weight. No significant differences (p˃0.05) in average weight gain, apparent feed conversion ratio (AFCR), daily weight gain, gross fish yield and net fish yield were observed. The study revealed that Giant African Snail (GAS) can be used either as partial or total replacement for soyabean as protein source for the fish. The use of harmful pest A. fulica in fish feed shows bright prospect in reducing the feeding expenses together with its suitable management.

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Aquafeed extrusion (review)

TAURIDA HERALD OF THE AGRARIAN SCIENCES ◽

10.33952/2542-0720-2021-1-25-38-49 ◽

2021 ◽

Vol 1 (25) ◽

pp. 38-49

Author(s):

S.V. Braginets ◽

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O.N. Bakhchevnikov ◽

V.F. Khlystunov ◽

◽

...

Keyword(s):

English Language ◽

Raw Materials ◽

Extrusion Process ◽

Animal Origin ◽

Fish Feed ◽

Scientific Publications ◽

Feed Composition ◽

Plant Raw Materials ◽

New Type ◽

Extruded Feed

Extrusion is one of the most important technological operations in aquafeed production. Indeed, the digestibility of feed nutrients considerably increases as a result of extrusion. The review deals with the issues of vegetable and animal raw materials processing for aquafeed production through extrusion. The analysis of scientific publications discussing the monitoring subject showed that extrusion of multicomponent mixtures (compound feed) had been studied insufficiently. Research objectives were to generalize and analyze English-language scientific publications containing information on the technologies of compound fish feed extrusion, to clarify the information on the rational parameters of their implementation and the effects on the properties of finished extruded feed. Search, selection, as well as systematic review of highly cited English-language scientific articles on the research subject for the period 2000–2020, were carried out. In the course of the analysis of literary sources, it was detected that the properties of the finished extruded feed were mostly affected by the extrusion temperature, raw material moisture and screw speed. The regularities of changes in the properties of ready-extruded feed granules, as a result of changes in extrusion parameters, have been determined. The results of the analyzed scientific articles made it possible to establish the peculiarities of the extrusion of compound feed for aquaculture based on plant raw materials, in particular starch. We defined the regularities of compound fish feed extrusion containing raw materials with a considerable amount of protein of animal origin, in particular its new type: insects’ biomass. This new type of protein-containing raw materials of animal origin can successfully replace expensive fish meal in the fish feed composition. The essential factor, limiting the application of animal raw materials in fish feed, in particular insects, is its moisture, which should not exceed 30% so that the extrusion process was fully effective. Reducing the feed mixture moisture is possible when combining various types of animal and plant raw materials with high and low moisture. This will ensure the acceptable moisture of the mixture and get the high-quality extruded feed. Aquafeed extrusion is a promising trend. However, it requires additional research to determine the parameters of the extrusion process common to all types of both plant and animal raw materials and their mixtures.

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Perception and awareness of insects as an alternative protein source among fish farmers and fish feed traders

Journal of Insects as Food and Feed ◽

10.3920/jiff2017.0056 ◽

2019 ◽

Vol 5 (2) ◽

pp. 107-116 ◽

Cited By ~ 4

Author(s):

G. Ssepuuya ◽

C. Sebatta ◽

E. Sikahwa ◽

P. Fuuna ◽

M. Sengendo ◽

...

Keyword(s):

Fish Meal ◽

Fish Farming ◽

Cross Sectional Study ◽

Protein Source ◽

Fish Feed ◽

Positive Perception ◽

Chi Square ◽

Cross Sectional ◽

Alternative Protein ◽

Willingness To Use

The perception of key players in the fish farming sector towards the use of insects is important for their acceptance to adopt insects as an alternative protein source to the expensive fish meal. Perception was established through a cross-sectional study of 208 fish farmers and 71 fish feed traders and/or processors conducted in Gulu, Tororo and Masaka districts in Uganda, using descriptive, Chi-square, correlation and factor statistical analysis of the data collected. Males dominated the fish farming and fish feed trading and/or processing enterprises. Youths were involved to almost the same extent as adults. Fish farmers majorly practiced pond fish farming, mainly using vegetable and grain based feeds. Most fish farmers (94.9%) and feed traders or processors (91.5%) were willing to use insects for feed but only 44.8% of fish farmers and 8.6% of feed traders and processors had ever used insects. All insects ever used by the respondents for feeding fish, including white ants, grasshoppers, termites and cockroaches were not reared but harvested from the environment. Willingness to use (rear/buy/sell) insects as fish feed was significantly and positively correlated with farmers’ and fish feed traders’ and/or processors’ perception that insects were good sources of nourishment for fish. Familiarity with use of insects and knowledge/awareness of their use significantly contributed to respondents’ positive perception. The apparent willingness to use insects for feeding fish should be promoted by encouraging mass insect production. Assessment of the consumer’s acceptability of fish reared on insects is necessary to ensure market for insect-fed fish.

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