Preference For Fish Research Articles

Taste preferences and feeding behaviour in the facultative herbivorous fish, Nile tilapia Oreochromis niloticus.

Taste preferences in fishes are known mainly for carnivorous species, whereas herbivorous consumers were rarely used in such studies. The main goal of the present study was to evaluate the taste preferences in the herbivorous African cichlid fish, Nile tilapia Oreochromis niloticus. In laboratory settings, the palatability of widely used taste substances (four taste substances that are considered to be sweet, sour, bitter and salty for humans - sucrose, citric acid, calcium chloride and sodium chloride; 21 free L-amino acids; 12 sugars and artificial sweetener Na-saccharin; 0.1-0.0001 M) was evaluated. In each trial, a standard agar pellet flavoured with a substance was offered for fish individually. The consumption of pellet, the number of grasps and the retention time before the pellet was finally ingested or rejected were registered. Overall, 21 of 38 substances were palatable, whereas other substances did not shift consumption of pellets in relation to blank pellets. Pellets containing citric acid, L-cysteine, L-norvaline, L-isoleucine, L-valine, Na-saccharin and D-sorbitol were consumed in >85% of trials. Taste attractiveness of amino acids was highly species-specific and was not associated with the trophic category of the 19 species compared. Moreover, it did not correlate with dietary quantitative requirements of Nile tilapia (rs =0.27; P > 0.05). Palatability of sugars for O. niloticus and their sweetness for humans did not correlate as well (rs =0.21; P > 0.05); nonetheless, Na-saccharin has the most attractive taste for both O. niloticus and humans. The most palatable amino acids lost their effect if the concentration was lowered to 0.01 M for L-cysteine and 0.001 M for L-norvaline (lower than 242.3 μg and 23.4 μg per a pellet, respectively). Single pellet grasp was characteristic of O. niloticus feeding behaviour (>95% of trials), and this pattern may be related to the social lifestyle of this species. Fish spent 4-8 s on average for orosensory evaluation of pellet edibility. The retention time correlated with the palatability of substances and was significantly longer in trials that ended up with pellet swallowing. It is suggested that prolonged orosensory evaluation of food before swallowing provides a reliable and accurate sensory evaluation, which, in turn, can reduce the probability that inadequate food will be consumed.

Consumer acceptability test on the organoleptic factors of dedawang pindang fish in Dedawang Hamlet, Bawean Island, Indonesia

This study aims to measure the level of consumer preference for organoleptic factors of pindang fish produced from the traditional scavenger business of Dedawang Hamlet, Telukjati Dawang Village, Tambak Sub-district, Bawean Island - Gresik Regency.The research was conducted from July to September 2020 involving 221 respondents from various backgrounds as panelists to assess the level of preference for pindang fish. The test material came from one of the scaling efforts carefully selected by the researcher. The organoleptic test includes 8 (eight) things, namely: taste, deviated odor (indication of deterioration), specific aroma, color, appearance, consistency, packaging aesthetics, and durability. The results showed that the durability factor (score 93.57), product aesthetics (score 90.48), smell (score 86.35), and distinctive aroma (score 81.35) were the main attractions for consumers buying pindang fish. While the appearance (score 53.07), consistency (score 63.51), color (score 65.41), and taste (score 68.17) are things that need to be improved to increase attractiveness to consumers. Keywords: organoleptic, pindang, consumer acceptability

Measurement of emotional states of zebrafish through integrated analysis of motion and respiration using bioelectric signals

Fear, anxiety, and preference in fish are generally evaluated by video-based behavioural analyses. We previously proposed a system that can measure bioelectrical signals, called ventilatory signals, using a 126-electrode array placed at the bottom of an aquarium and achieved cameraless real-time analysis of motion and ventilation. In this paper, we propose a method to evaluate the emotional state of fish by combining the motion and ventilatory indices obtained with the proposed system. In the experiments, fear/anxiety and appetitive behaviour were induced using alarm pheromone and ethanol, respectively. We also found that the emotional state of the zebrafish can be expressed on the principal component (PC) space extracted from the defined indices. The three emotional states were discriminated using a model-based machine learning method by feeding the PCs. Based on discrimination performed every 5 s, the F-score between the three emotional states were as follows: 0.84 for the normal state, 0.76 for the fear/anxiety state, and 0.59 for the appetitive behaviour. These results indicate the effectiveness of combining physiological and motional indices to discriminate the emotional states of zebrafish.

Assessment of the intention to consume farmed fish using the theory of planned behaviour

One-quarter of fish consumed in Europe comes from aquaculture and research has shown that consumers have a greater preference for wild fish in comparison with farmed ones. As with other food choices, consumer decisions regarding farmed fish are a complex process involving multiple factors. The main objective of this study is to develop and validate a questionnaire that will measure consumer intentions in the consumption of farmed fish using the theory of planned behaviour (TPB) as a theoretical framework. Based on the TPB model, the study also investigates the relationships between attitudes, subjective norms, perceived behavioural control and intention to consume farmed fish. Data collection was performed through an online survey and a total of 118 valid questionnaires were analysed. Based on tests performed, results indicate that the tested scale for measuring TPB constructs is valid and reliable. Alpha coefficients for intention, attitudes, subjective norms and perceived behavioural control were 0.898, 0.857, 0.748 and 0.953, respectively. Variables in the model explain 40% of the variation in farmed fish consumption intentions. Regression analysis confirmed that attitudes and subjective norms significantly influence intention to consume farmed fish, with the subjective norms being the strongest predictor, while perceived behavioural control does not have a significant impact on behavioural intention.

A comparative analysis of the effect of low-cost fish and commercially compounded feed on growth performance and organoleptic quality of hybrid grouper (Epinephelus fuscoguttatus × Epinephelus lanceolatus) in cage farming in Kuala Penyu, Sabah, and nutritional costs

A 25-week feeding trial was conducted to assess the growth performance, organoleptic quality, and to estimate the viability of nourishing hybrid grouper (Epinephelus fuscoguttatus x Epinephelus lanceolatus) with low-cost fish (LCF) and commercially compound feed (CCF). A group of 3600 juvenile fish (182g) were released in four sea cages and fed with either LCF or CCF in duplicate. At the end of the trial, the hybrid grouper provided LCF attained a significantly higher (P<0.05) final body weight (971.00±24.04g) than those fed with CCF (838.50±17.68g). While the estimated feed cost of hybrid grouper fed with LCF (RM7.84 ± 0.45) was lower than those fed with CCF (RM9.28 ± 0.37), no significant difference was found in the fish survival and there was no clear bias in consumer preferences for either fish fed with LCF or CCF (P>0.05). Although technicalities of fish fed with LCF suggest that LCF is more efficient than CCF, feeding LCF to high-value fish is an unsustainable practice as LCF is usually obtained through trawling – a destructive fishing method for the marine ecosystem. Therefore, feeding with CCF without the use of LCF as the source of protein for its fishmeal will contribute to sustainable aquaculture. In order to convince the local farmers in Sabah to adopt the practice of feeding CCF, future research should focus on completing the species-specific diet formulation to promote optimum growth, and find ways to reduce the CCF local selling price.

Animal and Plant Remains from Two Kalenderberg Group (Hallstatt Culture) Cremation Graves in Devín-Záhrady, Slovakia

The flotation of deposits from two recently excavated Kalenderberg Group cremation graves in DevínZáhrady (SW Slovakia) yielded a plethora of archaeozoological and archaeobotanical remains, including small, otherwise overlooked, ecofacts. The results of our analysis in the context of contemporary data show that animals clearly constituted an unambiguous part of funerary ritual activities. Pig, fish, red deer, cattle and caprines were all exploited at Devín-Záhrady. These animals represented both food and symbolic offerings, with a preference for pig and fish. Cattle, red deer, pig and caprines astragali found in grave 2 were all associated with one of the urns. The age of perinatal piglets was used to indicate the season when the funerals took place. Plant macro-remains are much less common than bone remains and are not associated with the burial. The results of the analysis change what is known about the array, quantity and way animal and plant offerings from Kalenderberg Group cremation graves were prepared for the burial ritual. Their study also permitted residual and intrusive materials to be detected, allowed reconstruction of the deposit’s formation processes and establishment of the connections (or absence of connections) between these ecofacts to the funeral and/or burial ritual.

Juvenile Nile Tilapia Fish Avoid Red Shelters

ABSTRACT Shelters are frequently used for fish rearing to improve welfare conditions. In this study, whether Nile tilapia prefers specific shelter colors was evaluated. Thus, fish preference for white, red, blue, green or yellow shelters was tested. A high variation of individual preference responses for the shelter colors among fish was found. Even so, while red shelter was clearly avoided by Nile tilapia, a clear-cut preference could not be concluded. Thus, avoiding red shelters for rearing Nile tilapia is recommended, assuming fish preference, or non-preference, as important elements considering welfare conditions. Moreover, individual variability should also be considered whenever possible.

Factors affecting consumers´ preferences for products from aquaculture

Fish is an essential component of a balanced and healthy diet and the present demand for fish cannot be sustained by capture fisheries. Consequently, aquaculture is currently the fastest growing food production industry in the world, contributing to more than half of the global fish production intended for human consumption. Although the image of aquaculture is not necessarily negative per se, consumers around the world still have a greater preference for wild fish. Therefore, the aim of this review is to critically evaluate some of the factors which may affect consumer preferences: socio-demographic characteristics of consumers, quality and safety perception of products from aquaculture, price of aquaculture products and socio-economic aspects of aquaculture, and concerns about the negative impact of aquaculture on the environment and about the sustainability of the production method. A literature review confirmed that age is the most influential sociodemographic variable. Being younger, female or having higher income and a higher education level can result in greater preference for aquaculture products. The image of farmed fish suffers from a perception of lower quality in terms of taste, health and nutritional value and, in some cases, even from low safety perceptions. On the other hand, farmed fish is believed to have lower prices and greater availability. Additionally, economic benefits are one of the main advantages of aquaculture. Mixed results emerge, however, with regard to the environmental impact of aquaculture, but sustainable production may compensate for possible environmental concerns and drive preference for farmed fish. Depending on how consumers weigh up the advantages and disadvantages of both aquaculture and its products, this will result in a preference for wild or farmed fis

Time Series Changes in Fish Assemblages and Habitat Structures Caused by Partial Check Dam Removal

Despite a steep increase in dam removal projects, there are few studies on the biophysical responses to dam removal. In this study, we evaluated the short-term (1.5 years) and long-term (5.5 years) effects of partial check dam removal on fish assemblages and their habitats. First, the habitat preferences of fish were examined at a channel unit scale: pools, rapids, and side channels satisfied the seasonal habitat requirements of the fish assemblages. Partial check dam removal increased the abundance of these habitats and diversified the habitat structures owing to the sediment release from the dam; in contrast, the bedrock distinctly decreased 1.5 years after dam removal. However, 5.5 years after dam removal, the bedrock proportion increased, and the habitat structures were simplified again owing to the re-transportation of sediments. Similar temporal changes were also determined through a reach-scale analysis with a change in the bed materials. Anadromous Oncorhynchus masou began to spawn and recolonize in the upstream section of the dam after the dam removal, causing similar assemblage compositions between the downstream and upstream sections. The abundance of Salvelinus malma and Noemacheilus barbatulus toni in the upstream reaches decreased over time after the dam removal. The temporal changes in the biophysical responses suggest that long-term monitoring is indispensable for the reliable evaluation of dam removal effects.

Dietary patterns and oesophageal cancer: a multi-country latent class analysis

BackgroundThe considerable differences in food consumption across countries pose major challenges to the research on diet and cancer, due to the difficulty to generalise and reproduce the dietary patterns identified...

Habenula kisspeptin retrieves morphine impaired fear memory in zebrafish

The habenula is an evolutionarily conserved brain structure, which has recently been implicated in fear memory. In the zebrafish, kisspeptin (Kiss1) is predominantly expressed in the habenula, which has been implicated as a modulator of fear response. Hence, in the present study, we questioned whether Kiss1 has a role in fear memory and morphine-induced fear memory impairment using an odorant cue (alarm substances, AS)-induced fear avoidance paradigm in adult zebrafish, whereby the fear-conditioned memory can be assessed by a change of basal place preference (= avoidance) of fish due to AS-induced fear experience. Subsequently, to examine the possible role of Kiss1 neurons-serotonergic pathway, kiss1 mRNA and serotonin levels were measured. AS exposure triggered fear episodes and fear-conditioned place avoidance. Morphine treatment followed by AS exposure, significantly impaired fear memory with increased time-spent in AS-paired compartment. However, fish administered with Kiss1 (10–21 mol/fish) after morphine treatment had significantly lower kiss1 mRNA levels but retained fear memory. In addition, the total brain serotonin levels were significantly increased in AS- and Kiss1-treated groups as compared to control and morphine treated group. These results suggest that habenular Kiss1 might be involved in consolidation or retrieval of fear memory through the serotonin system.

Morphotype‐dependent feeding responses in the guppy Poecilia reticulata Peters, 1859 (Class: Actinopterygii) fed zooplankton

Many aquarium fish species have diverse morphotypes. Since different morphotypes may have different preferences for various prey items, offering a single prey species is inadequate for successful aquaculture. Poecilia reticulata, a popular aquarium species, occurs in different morphotypes. To test whether the four morphotypes (yellow tail YT, red tail RT, metallic blue tail MBT and black tail BT) of this fish prefer different items, we quantified somatic growth, feeding behaviour, zooplankton selectivity and functional responses. Standard length (4.5 vs. 11.7 mm) and gape size (0.37 vs. 0.91 mm) of four morphotypes increased linearly with larval age; YT and RT had 25% longer body length and larger gape than the others. Prey encounters, attacks, captures and ingestions increased with larval age. Lowest ingestion rates were recorded for the RT morphotype on rotifers. At any given larval age, prey consumption increased with increasing prey availability. During the fourth and fifth weeks, larval YT and RT consumed higher number (37 ± 1 ind./predator/30 min) of cladocerans compared with other two morphotypes (24 ± 1 ind./predator/30 min). Prey selectivity data showed that larvae of MBT and BT continued to prefer rotifers up to 4 weeks, while those of YT and RT preferred cladocerans during the 4th week.

Improving nutrient and water use efficiencies in multi-loop aquaponics systems

The sustainable development of agricultural systems where nutrients and water are recycled to a high degree is of enormous importance. Traditional aquaponics, where fish and plants are cultivated in one recirculating system, addresses these ecological challenges, but still struggles with its economical feasibility. Decoupled multi-loop aquaponics systems, in which the aquaculture and hydroponics subsystems are running autonomously, proved that they can keep up with the productivity of state-of-the-art hydroponics systems or even outscore them. Yet, a problem of such decoupled aquaponics systems was that plants require a high nutrient concentration, whereas fish prefer rather a clean water. In practice, the opposite is happening as the nutrients are added to the aquaculture units through the feed. This paper optimizes a recent approach showing that desalination technologies, such as reverse osmosis, can play an important role in reversing the concentrations within such systems without killing beneficial plant growth–promoting rhizobacteria thermally. The proposed integrated systems approach has the potential to make both periodical nutrient and water discharges and excessive fertilizer supplementation obsolete that would otherwise be necessary to maintain good water quality for the fish and an optimal nutrient solution for the plants.

Biology and fishery of Acoupa Weakfish Cynoscion acoupa (Lacepède, 1801): a review

The present study describes the fishery and biology of Acoupa Weakfish Cynoscion acoupa, an important fishery resource in South America. We found and analyzed 31 articles and 10 publications about the species. Cynoscion acoupa is an estuarine marine species, which has a feeding habit with preference for fish and crustaceans. Its spawning occurs during two periods of the year and the size at maturity of females is 40 to 50 cm, while males mature earlier, with 38–40 cm. Their growth is considered slow to moderate, with growth coefficient k ranging from 0.13 to 0.28, and the species can reach up to 15 years of age. C. acoupa is target of commercial and recreational fisheries in estuarine and marine coastal environments, mainly in the northern region of South America. The fisheries occur throughout the year, with different fishing gear, being more frequent with gillnets. In addition, fishing is more frequent on juveniles, which may compromise the stock. This species is categorized as of Least Concern by the International Union for Conservation of Nature, although it has a high degree of vulnerability to fishing, which, combined with overexploitation, shows that C. acoupa should be listed as under threat of extinction to some degree. The lack of studies on the species makes it difficult to establish management measures. Therefore, further studies should be prioritized, especially on reproductive biology, growth and fishing exploitation.

How caged salmon respond to waves depends on time of day and currents.

Disease, pest control, and environmental factors such as water quality and carrying capacity limit growth of salmon production in existing farm areas. One way to circumvent such problems is to move production into more exposed locations with greater water exchange. Farming in exposed locations is better for the environment, but may carry unforeseen costs for the fish in those farms. Currents may be too strong, and waves may be too large with a negative impact on growth and profit for farmers and on fish welfare. This study employed two major fish monitoring methods to determine the ability of Atlantic Salmon (Salmo salar) to cope with wavy conditions in exposed farms. Echosounders were used to determine vertical distribution and horizontal preference of fish during different wave and current conditions as well as times of day. Video cameras were used to monitor shoal cohesion, swimming effort, and fish prevalence in locations of interest. The results indicate complex interacting effects of wave parameters, currents, and time of day on fish behaviour and vertical distribution. During the day, hydrodynamic conditions had stronger effects on vertical distribution than during the night. In weak currents, fish generally moved further down in taller waves, but stronger currents generally caused fish to move upwards regardless of wave conditions. Long period waves had unpredictable effects on vertical distribution with fish sometimes seeking deeper water and other times moving up to shallower water. It is unclear how much the cage bottom restricted vertical distribution and whether movement upwards in the water columns was related to cage deformation. In extreme cases, waves can reach below the bottom of a salmon cage, preventing fish from moving below the waves and cage deformation could exacerbate this situation. Farmers ought to take into consideration the many interacting effects on salmon behaviour within a cage as well as the potential for cage deformation when they design their farms for highly exposed locations. This will ensure that salmon are able to cope when storms and strong currents hit at the same time.

The Influence of Parents and Other Factors on Adolescents’ Fish Consumption in Selected Senior High School Students, Jakarta

Fish is an important source of animal food for adolescents because it contains various nutrients. Indonesia has high fish availability, but the level of domestic fish consumption in adolescents is still low. Lower fish consumption during adolescence will affect health status in the future. It is thus important to understand the various factors that influence fish consumption in adolescents. This study aimed to obtain information on fish consumption frequency; to investigate the associations between individual, socio-physical and environmental factors of adolescents and their fish consumption; and to examine the influence of parental eating behavior and support on adolescents’ fish consumption. Samples were chosen from adolescents aged 15-17 years. This study used a cross-sectional design. Data collection was obtained through filling out questionnaires, anthropometric data, and completing a semi-quantitative food frequency questionnaire (SFFQ). Bivariate analysis was conducted using the chi-square test and multivariate analysis was conducted using multiple logistic regression. The average fish consumption was found to be 34.1 grams/day. Fish consumption was significantly associated with attitude, preference, parental influence, and availability of fish at home (p<0.05). Further analysis showed that parental influence was the dominant factor related to fish consumption in students. This means that various parties, especially parents, can take a role in increasing fish consumption in students.

The ontogeny of continuous quantity discrimination in zebrafish larvae (Danio rerio).

Several studies have investigated the ontogeny of the capacity to discriminate between discrete numerical information in human and non-human animals. Contrarily, less attention has been devoted to the development of the capacity to discriminate continuous quantities. Recently, we set up a fast procedure for screening continuous quantity abilities in adult individuals of an animal model in neurodevelopmental research, the zebrafish. Two different sized holes are presented in a wall that divides the home tank in two halves and the spontaneous preference of fish for passing through the larger hole is exploited to measure their discrimination ability. We tested zebrafish larvae in the first, second and third week of life varying the relative size of the smaller circle (0.60, 0.75, 0.86, 0.91 area ratio). We found that the number of passages increased across the age. The capacity to discriminate the larger hole decreased as the ratio between the areas increased. No difference in accuracy was found as a function of age. The accuracy of larval zebrafish almost overlaps that found in adults in a previous study, suggesting a limited role of maturation and experience on the ability to estimate areas in this species.

Consumers’ Preference and Behaviour Pattern Towards Fresh and Smoked Catfish in Ilorin Metropolis, Nigeria

Consumers’ preference study allows industries to tailor the supply towards the preference of consumers so that market could be optimized for their turn-over and profits. This study investigated consumers’ preference of fresh and smoked catfish in Ilorin Metropolis. A total of 225 questionnaires were administered adopting multi-stage techniques to elicit information from the respondents. The obtained data were subjected to descriptive and inferential statistics. The results showed that majority of the respondents in this study preferred smoked catfish irrespective of their socio-economic profile. The majority of the respondents agreed with the factors used in this study for the preference of fish (i.e. types) and their frequency of eating as their preferred fish. This study showed that only tribe of the respondents showed significant effect (p<0.05) on the respondents’ preferences for whole or chunk fish; and family size, age and religion had significant effect on the frequency of their preferred fish.

In humans, only attractive females fulfil their sexually imprinted preferences for eye colour

Early exposure to parental features shapes later sexual preferences in fish, birds, and mammals. Here I report that human males’ preferences for a conspicuous trait, colourful eyes, are affected by the eye colour of mothers. Female faces with light (blue or green) eyes were liked better by men whose mother had light eyes; the effect broke down in those who had felt rejected by her as children. These results, garnered on over one thousand men, complete those of a symmetrical study on one thousand women, painting a fuller picture of human sexual imprinting. Both men and women appear to have imprinted on their opposite-sex parents unless these were perceived as cold and unjustly punitive. Birds require strong attachment to sexually imprint—a constraint in place to reduce the perils of acquiring the wrong sort of information. Parents who form no bond with their offspring may fail to be recognised as appropriate parental imprinting objects. Consistent with human females being, as in most of the animal kingdom, the choosier sex, imprinted preferences were displayed by both sexes but translated into real-life partner choices solely in women—attractive women. Apparently, not all of us can afford to follow our own inclinations.

Species-specific schooling behaviour of fish in the freshwater pelagic habitat: an observational study.

Social living of animals is a broadly occurring phenomenon, although poorly studied in freshwater systems, fish schooling behaviour is an excellent example. The composition of fish schools, species-specific schooling tendencies and preferences of adult fish were studied in the pelagic habitat of the Římov Reservoir, Czech Republic. Video recordings captured over a total of 34 days (16 h per day) in the clear water period of three seasons were analysed. From four species identified as school-forming species - bream, bleak, roach and perch, 40% of the individuals observed formed schools of 3-36 individuals. Although conspecific schools prevailed, 20% of individuals formed heterospecific schools, except bleak that schooled strictly with conspecifics. Schools were composed of individuals of similar body size and life strategy. Heterospecific schools were significantly larger than conspecific schools and showed uneven proportion among species, that is, one species being more abundant when the school dimension increased. Probability of encounter in bleak was lowest and proved highest inclination for schooling. Gregarianism levels depended on species morphology and body size, with larger and morphologically advanced fish tending less to sociability. This indicates that the antipredator function of schooling behaviour is intensified with increasing vulnerability of the species.