Next Article in Journal
The Combined Effects of Cadmium and Microplastic Mixtures on the Digestion, Energy Metabolism, Oxidative Stress Regulation, Immune Function, and Metabolomes in the Pearl Oyster (Pinctada fucata martensii)
Previous Article in Journal
Imidacloprid Exposure Induced Impaired Intestinal Immune Function in Procambarus clarkii: Involvement of Oxidative Stress, Inflammatory Response, and Autophagy
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

The Physiological Benefits and Economic Value of Using Fairy Shrimp as Fish Meal for Flowerhorn Cichlids; Amphilophus citrinellus (Günther, 1864) × Cichlasoma trimaculatum (Günther, 1867)

by
Ploychompoo Weber
1,
Supranee Wigraiboon
2,
Nantaporn Sutthi
2,
Pattira Kasamesiri
3 and
Wipavee Thaimuangphol
2,*
1
Mahasarakham Business School, Mahasarakham University, Maha Sarakham 44150, Thailand
2
Applied Animal and Aquatic Sciences Research Unit, Division of Fisheries, Faculty of Technology, Mahasarakham University, Maha Sarakham 44150, Thailand
3
Faculty of Technology, Mahasarakham University, Maha Sarakham 44150, Thailand
*
Author to whom correspondence should be addressed.
Fishes 2025, 10(3), 132; https://doi.org/10.3390/fishes10030132
Submission received: 9 February 2025 / Revised: 9 March 2025 / Accepted: 13 March 2025 / Published: 18 March 2025
(This article belongs to the Section Physiology and Biochemistry)

Abstract

The aim of this study was to evaluate the utilization of fairy shrimp (Branchinella thailandensis) meal in the diets of flowerhorn cichlids, on their growth, skin coloration, carotenoid content, antioxidant activity, and innate immunity. The fish were fed diets incorporated with fairy shrimp meal at 0% (control; FS0), 10% (FS10), 20% (FS20), and 30% (FS30) for 60 days. The results showed that growth performance and chemical composition were not significantly different among treatments (p > 0.05), whereas fish fed the 30% fairy shrimp meal (FS30) diet represented significantly enhanced skin coloration, particularly in terms of redness (a*) and dominant wavelength (H°ab). The highest level of antioxidant enzymes and non-specific immune enzymes such as SOD and lysozyme were observed in the fish fed the FS30 diet. Meanwhile, increasing fairy shrimp meal significantly reduced the liver function markers (ALT and AST), and decreased lipid peroxidation. These findings suggest that fairy shrimp meal serves as a valuable dietary ingredient for enhancing skin pigmentation, boosting antioxidant defense, and stimulating immune responses in flowerhorn cichlids. Moreover, the economic evaluation of using fairy shrimp meal as an ingredient for ornamental fish demonstrates promising investment potential, supporting its application in commercial aquaculture.
Key Contribution: This study is the first to report that incorporating fairy shrimp as a dietary ingredient positively affects the hematological profile, antioxidant activity, physiological performance, and immune responses of fish. Incorporating fairy shrimp into pelleted diets can be commercially produced at a cost-effective price while maintaining manufacturer profitability.

1. Introduction

Flowerhorn cichlids are one of the most important economic ornamental fish species. They are popular worldwide due to their vibrant colors, unique body shapes, and captivating behavior [1]. The beautiful appearance of these ornamental fish depends on proper nutrition to promote growth, coloration, and immunity [2,3]. Pigmentation or coloration of ornamental fish is an essential characteristic for world market acceptability, with carotenoids responsible for the pigmentation of several ornamental fish species [4,5]. Ornamental fish cannot biosynthesize carotenoids in their bodies and their coloration relies on a carotenoid-rich diet. Carotenoids are natural pigments that are present in various algae, plants, animals, and some bacteria [6]. Carotenoids have excellent antioxidant properties and are used as feed supplements to enhance cell growth, immune systems, and disease resistance [7]. These multifaceted functions make carotenoids indispensable for the well-being of ornamental fish. Incorporating carotenoid-rich diets in aquaculture practices could help to improve growth, survival, coloration, and disease resistance in commercial ornamental fish.
Fairy shrimp are small crustaceans (Anostraca) commonly found in temporary water bodies. They are popular live feed for freshwater aquaculture of ornamental fish because of their high nutritional value including proteins, amino acids, and essential fatty acids. Fairy shrimp contain high amounts of carotenoids [8] and have been studied as a potential food source for fish [9,10] and shrimp [11,12] in aquaculture. Feeding fish and prawns with fairy shrimp improved the fecundity and hatching percentage of aquatic animals such as angel fish, green tailor fish, and cray fish (Procambarus clarkii) [13,14]. Research suggests that fairy shrimp are a valuable food source in aquaculture [15] and provide nutritional benefits to different aquatic organisms [16,17]. Many previous studies have focused on the use of live fairy shrimp but the development of fairy shrimp as meal in the diet has not been addressed. Fairy shrimp in formulated feeds for aquarium fish showed enhanced skin pigmentation. Dried fairy shrimp meal increased skin pigmentation and carotenoid deposition in flowerhorn cichlids [18]. However, limited research has examined the effects of formulated feeds containing fairy shrimp meal components on antioxidant activity, hematological parameters, blood chemical composition, and immunity relating to the health of ornamental fish. The potential benefits and drawbacks of incorporating fairy shrimp into formulated feeds to enhance the health of ornamental fish need to be explored.
Therefore, this research investigated the impact of incorporating dried fairy shrimp meal in feed on the growth performance, skin pigmentation, antioxidant activity, hematological parameters, blood chemical composition, and immunity of flowerhorn cichlids following treatment with newly formulated feeds containing fairy shrimp. Economic data of the newly formulated feed were also analyzed.

2. Materials and Methods

2.1. Fish Preparation and Experimental Design

Healthy flowerhorn cichlids, Amphilophus citrinellus (Günther, 1864) × Cichlasoma trimaculatum (Günther, 1867), were obtained from a commercial fish farm in Khon Kaen Province, Thailand and acclimated for 2 weeks at the Division of Fisheries, Faculty of Technology, Mahasarakham University, Maha Sarakham, Thailand. After acclimatization, the fish with an initial weight of 18.88 to 19.85 g were randomly transferred into 36 tanks (76 × 155 × 96.5 cm3) containing 40 L of dechlorinated tap water and divided into four experimental groups with nine replicates. During the feeding trial, the fish were fed twice daily with a feeding rate of 5% biomass per day throughout the 60-day experimental period. The tank water was exchanged every day (10%) to remove the remaining feed from the previous day by siphoning and the water volume was replaced. Water quality was maintained throughout the feeding trial (water temperature 28 ± 2 °C; dissolved oxygen ≥ 7.0 mg/L; pH 7.2–8.1; total ammonia nitrogen levels < 0.2 mg/L).

2.2. Preparation of Tested Diets

Four equal-nitrogenous (40% crude protein) and equal-energetic (428.51 Kcal/100 g) experimental diets were formulated by substituting 0% (FS0—control), 10% (FS10), 20% (FS20), and 30% (FS30) of fish meal protein with fairy shrimp protein. Fairy shrimp, Branchinella thailandensis, was received from Swed Thai Trading Co., Ltd., Samut Prakan, Thailand. B. thailandensis contains protein 64.65%, lipid 7.57%, carbohydrate 16.24%, fiber 5.12%, and ash 6.12% [8]. The diets were formulated with fish meal, fairy shrimp meal, soybean meal, wheat flour, corn meal, squid liver meal, red yeast, soybean oil, squid liver oil, and premix.
The ingredients were pressed through a 1 mm mesh and mixed. The pellets were dried in a hot air oven (UF750, Memmert, Schwabach, Germany) at 40 °C for 24 h and stored in bags in a freezer at −20 °C until used. Proximate analyses of the diets were performed using the standard methods of the Association of Official Analytical Chemists (AOAC) [19]. The formulation and basic nutrient composition of the experimental diets are given in Table 1.

2.3. Growth Performance Parameters

Every 15 days and at the end of the experiment, the fish were individually anesthetized in a clove oil solution (0.2 mL/L water) for 10 min. The total number and individual body length and weight of each fish were measured using an electronic balance and a vernier caliper to estimate the biometric indices. The survival rate, growth performance, and feed utilization of fish fed the test diets were determined according to the following formulae: survival rate (SR; %) = (number of survived fish/initial number of fish) × 100; weight gain (WG; g) = final body weight–initial body weight; specific growth rate (SGR; % d−1) = 100 × [(Ln (final body weight) − Ln (initial body weight))/duration]; average daily gain (ADG; %) = (final body weight − initial body weight)/duration; feed conversion ratio (FCR) = apparent feed intake/weight gain.

2.4. Skin Color Measurement

Skin coloration was measured in the skin zones on both lateral body sides of all fish. Measurements were recorded at the end of the feeding trial using a Chroma Meter (Chroma Meter CR-400, Konica Minolta, Osaka, Japan). The L*, a*, and b* parameters were measured based on the International Commission on Illumination (CIE) (CIE, 1976):
  • L* = lightness, where dark = 0 and white = 100;
  • a* = redness, where positive values = red and negative values = green;
  • b* = yellowness, where positive values = yellow and negative values = blue.
Chroma and hue angle (◦Hue) were calculated from a* and b* according to the following equations. Hue (H°ab) represents the dominant wavelength of a color; it is calculated using the H°ab = tan−1(b*/a*) but if a* < 0 then H°ab = 180 + tan−1(b*/a*). Chroma (C*) represents the colorfulness or saturation of a color and is calculated using the a* and b* values. C* = (a*2 + b*2)1/2 [20].

2.5. Total Carotenoid Analysis

The samples were dried in a hot air oven (UF750, Memmert, Schwabach, Germany) at 45 °C for at least 6 h and then ground to a powder using an electric homogenizer. Each sample was weighed to an accuracy of 0.5 g. Carotenoids were liberated from the samples by homogenization and suspension in 5 mL of acetone according to the previous methods [21] The supernatant was collected after centrifuging at 5000 rpm for 5 min, evaporated (rotary evaporator, RC900, KNF Neuberger GmbH, Freiburg im Breisgau, Germany) at 40 °C, and then dissolved in petroleum ether. The sample was saponified with 0.5 mL 60% KOH in the dark for 2 h. Carotenoids were extracted by partitioning in petroleum ether. The top layer was removed into another tube using a glass pipette. Then, 0.5 g of anhydrous sodium sulfate was added to the tube and left to stand for 15 min to absorb any residual water in the solution. Total carotenoid concentration was then measured for absorbance at 450 nm wavelength using a GENESYS™ 20 visible spectrophotometer (Thermo Fisher Scientific, Waltham, MA, USA) and the total carotenoid concentration was calculated.

2.6. Proximate Composition

Crude protein, crude lipid, moisture, fiber, and ash of the feed and the experimental fish were determined according to the methods of the Association of Official Analytical Chemists [19]. Moisture content was analyzed by oven drying at 105 °C (Memmert, Schwabach, Germany) until constant weight. Crude protein content (N × 6.25) was determined by the Kjeldahl method using an Auto Kjeldahl System (Buchi B324/K-437, Flawil, Switzerland). Crude lipid content was measured by hexane extraction using SOXTERM (Gerhardt GmbH, Königswinter, Germany). Ash content was determined by incineration in a muffle furnace at 550 °C for 7 h.

2.7. Blood Biochemical Analysis

Blood samples were collected and sent to the Veterinary Central Lab, Khon Kaen District, Khon Kaen 40000, Thailand for blood chemical analysis. For the blood chemistry parameters, the assays were run on an ABX Pentra 400 Clinical Chemistry Analyzer (HORIBA Medical, Montpellier, France). Each of the assays used was the standard kit developed for the auto-analyzer. Tests were performed for globulin, total protein, blood urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and cholesterol. Globulin was calculated by subtracting the value of albumin from the total protein.

2.8. Hematological Analysis

Total red blood cell (RBC) and white blood cell (WBC) counts were obtained using a standard Neubauer hemocytometer chamber. The hematocrit (Ht) was determined by filling hematocrit capillary tubes. The Ht values were recorded using a centrifuge combo-reader. Hemoglobin (Hb) concentration was measured by a lysing reagent kit (ABX reagent, Horiba, France) and used for erythrocyte lysis and cyanide-free determination of hemoglobin. The hemoglobin was released, and all the heme irons were oxidized and stabilized. The resulting complexes were quantified by spectrophotometry with a wavelength of 550 nm using a hematology analyzer (ABX Micros EVS 60, Horiba, Montpellier, France).

2.9. Innate Immune Parameters

Serum lysozyme activity was determined by the turbidimetric method based on the lysis of the lysozyme-sensitive Gram-positive bacterium Micrococcus lysodeikticus (Sigma Aldrich, St. Louis, MO, USA) following the method in [22]. The serum lysozyme activity was measured and expressed as U/mL. Briefly, a 25 µL aliquot of serum was added to 100 μL of the bacterial suspension (3.0 mg/mL in 0.05 M PBS pH 6.4), and the absorbance was measured at 450 nm after 30 s and 180 s (iMark™ Microplate Absorbance Reader, Bio-Rad Laboratories, Hercules, CA, USA).
The total myeloperoxidase (MPO) content present in the serum was measured [23,24], with slight modifications. Briefly, aliquots of 20 μL of serum were diluted with PBS in 96-well plates. Then, 35 μL of 20 mM 3,3′-5,5′-tetramethyl benzidine hydrochloride (Sigma, USA) and 5 mM of H2O2 were added. The color change reaction was stopped after 2 min by adding 35 μL of 4 M H2SO4. Finally, the OD was read at 450 nm (iMark™ Microplate Absorbance Reader, Bio-Rad Laboratories, Hercules, CA, USA).

2.10. Antioxidant Enzymes Activity and Lipid Peroxidation

Superoxide dismutase (SOD) activity was evaluated [24]. Briefly, 20 μL of serum was added to 940 μL of sodium carbonate buffer and 40 μL of epinephrine (30 mmol/L dissolved by adding 30 μL of HCL, Sigma, USA). The inhibition of epinephrine auto-oxidation in the alkaline medium to adrenochrome was recorded after 30 and 90 s at 480 nm using an iMark™ Microplate Absorbance Reader, Bio-Rad Laboratories, Hercules, CA, USA. A control was prepared using 960 μL of sodium carbonate buffer and 40 μL of epinephrine. The percent of inhibition (%) = 100 − ((ΔA control − ΔA sample/ΔA control) × 100). SOD activity in serum = % inhibition × 3.75.
Lipid peroxidation in terms of malondialdehyde (MDA) was determined by measuring the amount of thiobarbituric acid reactive substances (TBARS) [25]. The MDA concentration was measured using a GENESYS™ 20 Visible Spectrophotometer (Thermo Fisher Scientific, Dreieich, Germany) at 532 nm.

2.11. Economic Analysis of Experimental Diets

At the end of the experiment, an economic analysis was conducted to evaluate the financial feasibility of feeding flowerhorn cichlids with diets containing different levels of fairy shrimp meal. The analysis was performed in Thai Baht (THB) and Euro (EURO) using standard economic principles. The economic conversion ratio (ECR) assesses the feed cost efficiency using the following equation:
ECR (฿/kg fish) = FCR (kg diet/kg of fish) × Diet Price (฿/kg of diet)
The diet price was calculated based on the cost of individual feed ingredients in each formulated diet. This economic assessment provided insights into the cost-effectiveness and profitability of incorporating fairy shrimp meal into ornamental fish diets.

2.12. Statistical Analysis

Data for different treatments were tested for normality using a one-way analysis of variance (ANOVA) followed by Duncan’s post hoc test for multiple comparisons among the treatments. The significance level was set at p < 0.05. The handling of data that do not meet normal distribution or homogeneity of variance needs to be addressed.

3. Results

3.1. Growth Performances

The four diets were equally accepted by the fish with no mortalities in the treatments. There were no significant differences in weight gain (WG), average daily gain (ADG), specific growth rate (SGR), feed conversion ratio (FCR), and survival rate (Table 2).

3.2. Skin Coloration

After 60 days of the feeding trials, the skin coloration of the flowerhorn cichlids was evaluated for the parameters of lightness (L*), redness (a*), yellowness (b*), hue (H°ab), and chroma (C*) to assess any potential effects of the different experimental diets. The skin lightness (L*) and yellowness (b*) of flowerhorn cichlids on day 0 and day 60 were not significantly different among the different test diets (p > 0.05). The redness (a*) in fish fed with the FS30 treatment was significantly higher than in the other groups (p < 0.05) after 60 days of feeding. H°ab values were significantly lower than the control group.
On day 60, the redness (a*) in the FS30 group was significantly higher than in the other groups, with the FS10 and FS20 groups showing intermediate values and the control group exhibiting the lowest value. The chroma (C*) parameter, representing the color intensity, did not differ significantly among the treatment groups on day 0 and day 60. Feeding flowerhorn cichlids with the FS30 diet led to noticeable changes in their skin coloration, with increased redness and a shift toward a redder hue (Table 3).

3.3. Total Carotenoid Content

The total carotenoid contents in the diets and the fish fed different levels of fairy shrimp meal (FS) are presented in Table 4. Significant differences were observed among the dietary treatments in the diet and fish tissue (p < 0.05). The total carotenoid content in the diets increased with higher inclusion levels of fairy shrimp meal, with the highest concentration observed in the FS30 diet (93.2 ± 6.0 µg g−1), significantly higher than in the control, FS10, and FS20 diets (p < 0.05). Fish fed fairy shrimp-incorporated diets exhibited significantly higher carotenoid accumulation in their tissues compared to the control group. The highest carotenoid content in fish tissue was recorded in the FS30 group (22.81 ± 1.23 µg g−1), followed by FS20 (17.94 ± 1.27 µg g−1) and FS10 (15.26 ± 0.78 µg g−1), while the control group (FS0) had the lowest value (8.87 ± 0.65 µg g−1).

3.4. Proximate Analysis

The compositions of the experimental diets are shown in Table 1. The control diet contained 320 g kg−1 fish meal, which was gradually replaced with fairy shrimp meal at inclusion levels of 10% (FS10), 20% (FS20), and 30% (FS30). As the proportion of fairy shrimp meal increased, the inclusion of fish meal and soybean meal decreased accordingly. Wheat flour content increased with higher fairy shrimp meal levels to maintain the dietary formulation. Other ingredients including corn meal, squid liver meal, red yeast, soybean oil, squid liver oil, and premix were kept constant across all the diets.
The proximate compositions of the experimental diets indicated no significant differences (p > 0.05) among the treatments in terms of crude protein, crude lipid, moisture, ash, fiber, nitrogen-free extract (NFE), gross energy (GE), and caloric content (Table 5). The crude protein content ranged from 39.93% to 40.25%, while the crude lipid content varied between 3.17% and 3.37%. The moisture and ash contents showed minor variations but remained within similar ranges. Fiber content was consistent across all the diets with values between 1.14% and 1.17%. The energy content of the diets was also similar among treatments with values ranging from 428.06 to 430.66 kcal/100 g while gross energy (GE) ranged from 17.81 to 17.92 MJ/kg.
Incorporating fairy shrimp meal (FS) at different levels did not influence crude protein, crude lipid, moisture, ash, and fiber in the fish flesh (p > 0.05) (Table 6).

3.5. Blood Biochemical Assay

Blood biochemical parameters of flowerhorn cichlids fed different levels of fairy shrimp meal are presented in Table 7. Significant differences were observed in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase among the dietary treatments (p < 0.05). The lowest ALT (11.67 ± 0.88 U/L) and AST (43.33 ± 4.63 U/L) levels were recorded in fish fed the FS30 diet, significantly lower than the control and the other experimental groups (p < 0.05). The FS20 group showed a significant reduction in alkaline phosphatase activity (p < 0.05). No significant differences were observed in blood urea nitrogen (BUN), albumin, globulin, total protein, or cholesterol among the dietary treatments (p > 0.05).

3.6. Hematology

The hematological parameters of flowerhorn cichlids fed different levels of fairy shrimp meal are presented in Table 8. Significant differences were observed in red blood cell (RBC) count, hemoglobin concentration, hematocrit, white blood cell (WBC) count, neutrophil percentage, and lymphocyte percentage among the dietary treatments. The highest RBC count (1.04 ± 0.19 × 106 cells/mm3), hemoglobin concentration (4.30 ± 0 g/dL), and hematocrit level (13 ± 0%) were observed in fish fed the FS30 diet, significantly higher than those in the control and FS10 groups (p < 0.05). The WBC count was significantly higher in fish fed the FS20 (3040 ± 175 cells/mm3) and FS30 (3475 ± 110 cells/mm3) diets compared to the control and FS10 groups (p < 0.05). Neutrophil percentages were significantly higher in the FS20 (62.25 ± 2%) and FS30 (65 ± 0.50%) groups compared to the control and FS10 groups (p < 0.05), whereas lymphocyte percentages were significantly lower in these groups (31 ± 2% and 33.5 ± 0.50%, respectively) compared to the control and FS10 groups (p < 0.05). No significant differences were observed in eosinophil or monocyte percentages among the dietary treatments (p > 0.05).

3.7. Immunological Analysis

The non-specific immune enzyme activities of flowerhorn cichlids fed different levels of fairy shrimp meal (FS) are summarized in Figure 1. Serum lysozyme activity significantly increased with the inclusion of fairy shrimp meal in the diet (p < 0.05). The highest lysozyme activity was observed in the FS30 group (3.6 ± 0.23 U/mL), followed by FS20 (3.33 ± 0.35 U/mL) and FS10 (2.67 ± 0.48 U/mL) (Figure 1). The control group exhibited the lowest activity (1.6 ± 0.46 U/mL). Statistical analysis indicated that fish fed the FS20 and FS30 diets had significantly higher lysozyme activity compared to the control group (p < 0.05). Myeloperoxidase (MPO) activity, measured as absorbance at 450 nm, exhibited an increasing trend with higher levels of fairy shrimp meal but the differences were not statistically significant (p > 0.05). The highest MPO activity was recorded in the FS30 group (1.75 ± 0.07), followed by FS20 (1.71 ± 0.13) and FS10 (1.50 ± 0.05), while the control group had the lowest value (1.36 ± 0.09) (Figure 2).

3.8. Antioxidant Activities

The SOD activity showed a significant increase in the FS30 group (16.56 ± 0.31 U/mL) compared to the control (10 ± 0.63 U/mL) (p < 0.05). However, no significant differences were observed among the FS10 (10.78 ± 1.89 U/mL) and FS20 (11.09 ± 2.07 U/mL) groups compared to the control (Figure 3).

3.9. Lipid Peroxidation Analysis

MDA levels significantly decreased with increasing inclusion of fairy shrimp meal in the diet (p < 0.05). The highest MDA concentration was observed in the control group (126.67 ± 2.60 µM/L), followed by FS10 (125.69 ± 2.60 µM/L) and FS20 (118.82 ± 4.49 µM/L). The lowest MDA level was recorded in the FS30 group (102.16 ± 8.71 µM/L), significantly lower than the control group (p < 0.05) (Figure 4).

3.10. Economic Analysis of Diets Containing Different Levels of Fairy Shrimp Meal

The economic assessment of flowerhorn cichlids fed diets with varying levels of fairy shrimp meal (FS) was conducted based on feed ingredient costs and the economic conversion ratio (ECR) (Table 9). The cost of feed ingredients varied with the inclusion of fairy shrimp meal. The total diet price (THB/kg) increased with higher levels of FS, ranging from 153.95 THB/kg in the control group to 743.20 THB/kg in the FS30 group. When converted to euros (EUR/kg) based on an exchange rate of EUR 1 = THB 35 (as of 5 January2025), the diet cost ranged from 4.99 EUR/kg (control) to 24.08 EUR/kg (FS30).
The economic conversion ratio (ECR), representing the cost per unit of fish weight gain, increased with increasing FS levels. The ECR in Thai Baht (THB/kg fish) ranged from 155.49 THB/kg (control) to 772.93 THB/kg (FS30), while in euros (EUR/kg fish), it varied from 5.04 EUR/kg (control) to 25.05 EUR/kg (FS30). The market price of flowerhorn cichlids was estimated at 1080 THB/kg (30.86 EUR/kg). This comparison provides insights into the profitability of using fairy shrimp meal at different inclusion levels.

4. Discussion

Incorporating fairy shrimp into the diet of flowerhorn cichlids did not result in significant differences in growth performance, survival rate, feed utilization, and proximate composition compared to the control group. All the experimental diets were formulated to contain a consistent protein level at approximately 40% while maintaining a stable energy content of 425.57–431.22 Kcal/100 g. As a result, all fish received comparable protein and energy intakes which play an important role in the growth and development of living organisms [26], leading to no significant variations in growth performance or nutritional composition across treatments. These findings suggested that fairy shrimp meal effectively replaced fish meal in flowerhorn cichlid diets without compromising nutrient composition and energy balance. Incorporating fairy shrimp into pelleted diets did not affect the growth rate, survival rate, and chemical composition of flowerhorn cichlids but produced optimal color enhancement.
In the ornamental fish industry, carotenoids are commonly incorporated into farmed fish diets as a pigmentation source to enhance the desirable coloration of cultured ornamental species. Carotenoids represent a diverse group of pigments naturally synthesized by plants, algae, bacteria, fungi, and crustaceans [27,28]. Fairy shrimp are freshwater crustaceans and contain a high number of carotenoids, particularly astaxanthin, a red pigment that serves as an effective natural color enhancer for ornamental fish. B. thailandensis contain a high total carotenoid content of up to 254.41 µg g−1, with astaxanthin, canthaxanthin, and beta-carotene comprising the total carotenoids [8]. These findings indicated that inclusion of fairy shrimp meal in the diet enhanced carotenoid deposition in fish tissue. The highest accumulation occurred in fish fed the FS30 diet, suggesting that fairy shrimp meal is an effective natural pigment source for improving coloration in flowerhorn cichlids. When flowerhorn cichlids consumed B. thailandensis, the red coloration of their skin was visibly enhanced. The increase in fish skin color deposition may depend on the type of carotenoid. These findings concurred with previous studies on flowerhorn cichlids, reporting similar pigmentation enhancement effects [16]. Similarly with the previous study, fairy shrimp supplementation improved skin coloration in goldfish (Carassius auratus) without adversely affecting growth performance [29]. The high carotenoid content in fairy shrimp also influenced carotenoid accumulation within the fish body. Our results indicated that pelleted diets containing fairy shrimp meal exhibited a higher carotenoid content than the control diets, leading to greater carotenoid accumulation in fish that consumed fairy shrimp-enriched feed. This result aligned with previous research reporting that flowerhorn cichlids fed with fairy shrimp-enriched diets exhibited significantly higher carotenoid concentrations [16]. Similar findings have also been reported in giant freshwater prawns, Macrobrachium rosenbergii, where fairy shrimp supplementation led to increased carotenoid accumulation [12]. Carotenoids play an important role in modifying skin coloration and achieving optimal pigmentation [30] when incorporated into the diet. Carotenoids influence various physiological processes including antioxidant activity and immune function and contribute to physiological well-being by boosting the antioxidant defense system and strengthening immunity [31]. Carotenoids also play a protective role in mitigating stress-related conditions [32], making them an essential dietary component for maintaining fish health.
Serum blood biochemical analysis is a crucial tool for evaluating the physiological functions and overall health status of aquatic animals, as it provides insights into various metabolic processes, organ function, stress levels, and potential disease states by examining different components within the blood, making it a valuable method for monitoring aquatic animal health in research and aquaculture settings [33]. The ALT and AST are key indicators of liver function. These enzymes are found in liver cells which leak into the blood stream when the liver cells are damaged [34]. ALT and AST exhibited significantly lower levels in the FS30 group compared to the control, suggesting a potential positive effect on liver health. The significant decrease in AST and ALT levels was attributed to the large number of carotenoids produced by fairy shrimp [8]. Supplementing fish diet with carotenoids can reduce stress and lower AST and ALT activities [35]. A BUN test is performed to see how well the kidneys are working; it measures the amount of urea nitrogen in your blood. If the kidneys are not able to remove urea from the blood normally, the BUN level rises. Blood urea nitrogen (BUN) indicates kidney health [36]. This indicates that diets incorporating fairy shrimp had no toxic effects in the liver and kidney, as evidenced by the decrease in AST and ALT and the absence of significant changes in BUN.
Protein level is a commonly measured blood parameter in fish health. Blood proteins are involved in biological functions including maintaining osmotic pressure, pH regulation, transporting various metabolites, and playing an important role in fish humoral immunity. Levels of total proteins may hence provide insights into the nutritional, immune, or health status of fishes [35]. Proteins also play a role in blood clotting and endogenous antibody production, and globulin, also used as a raw material for producing antibodies that destroy pathogens (antibodies), plays an important role in the body’s defense mechanism [37]. In this study, total protein and globulin levels showed an increasing trend in fish fed fairy shrimp-incorporated diets, suggesting potential immune-enhancing effects. Although these differences were not statistically significant, the observed trends indicate that fairy shrimp incorporation may contribute to improved immune responses without adversely affecting other blood biochemical parameters. Similarly, blood cholesterol levels did not exhibit notable differences among the treatment groups, indicating that the incorporation of B. thailandensis meal at varying levels had no impact on cholesterol metabolism in flowerhorn cichlids.
Blood parameters can be reliable indicators for fish health and immune health [38]. Hematological parameters are impacted by dietary nutrition and environmental stressors and are often used to monitor fish health and physiological states. The complete blood cell count (CBC) can be used to monitor the health status of fish in response to changes related to nutrition in fish [39]. Our findings suggested that dietary incorporation with fairy shrimp meal, particularly at higher inclusion levels (FS20 and FS30), positively influenced hematological parameters such as red blood cell (RBC) count, hemoglobin, and hematocrit levels, indicating enhanced oxygen transport capacity in flowerhorn cichlids. The hematological profiles revealed an increase in white blood cell (WBC) count, neutrophils, and lymphocytes in fish fed with fairy shrimp meal compared to the control group, suggesting improved immune response. This study is the first to report that incorporating fairy shrimp as a dietary ingredient positively affected the hematological profile of fish. The observed immunostimulatory effects were attributed to the high carotenoid content in fairy shrimp, which plays a crucial role in enhancing immune function in fish.
Our findings concurred with previous studies demonstrating that carotenoid-rich diets improve hematological parameters in various fish species, including common carp (Cyprinus carpio) [40], striped catfish (Pangasianodon hypophthalmus) [41], goldfish (Carassius auratus) [42], and Nile tilapia (Oreochromis niloticus) [43]. Similarly, [44] reported that Asian seabass, Lates calcarifer, displayed significant enhancements in hematological indices (RBC count, hemoglobin, hematocrit, and WBC count) when fed various diets with elevated doses of carotenoids throughout the feeding. Similar previous studies reported that dietary carotenoid supplementation enhanced WBC, neutrophil, and lymphocyte levels, leading to improvement in fish immune response. Consistent with our results, fish fed diets rich in carotenoids exhibited a significant increase in RBC counts, hemoglobin levels, and hematocrit values compared to a control diet. These findings indicated that the beneficial effects of carotenoids on hematological parameters were dose-dependent, contributing to the activation of non-specific immunity in flowerhorn cichlids.
Non-specific immune enzymes, such as lysozyme and myeloperoxidase (MPO), play crucial roles in the innate immune system of fish by providing defense against pathogens [45]. Lysozymes are a group of molecules involved in host protection against bacterial invasion [46]. Our results indicated that lysozyme activity significantly increased in fish fed fairy shrimp meal, suggesting that the inclusion of fairy shrimp meal enhances non-specific immune responses in flowerhorn cichlids. MPO activity increased levels of fairy shrimp meal, but the differences were not statistically significant.
MPO is a key enzyme involved in the oxidative burst mechanism, which contributes to the elimination of pathogens [47]. The observed trend of increasing MPO activity in fish fed fairy shrimp meal suggested the improvement of the immune function, even though the statistical significance was not reached. The enhanced lysozyme and MPO activity in fish fed fairy shrimp meal may be attributed to its high carotenoid content, which has been reported to function as an immunostimulant in various fish species. Previous studies have demonstrated that dietary carotenoids can enhance the lysozyme level in Labeo rohita fish [48], dwarf chameleon fish (Badis badis) [49], and goldfish (Carassius auratus) [42]. On the other hand, MPO activity did not show any differences in this investigation. These findings supported the hypothesis that fairy shrimp meal supplementation positively affects the innate immune system by stimulating the activity of non-specific immune enzymes. The results suggested that incorporating fairy shrimp meal in the diet of flowerhorn cichlids improves their non-specific immune response, likely due to the immunostimulatory effects of carotenoids and other bioactive compounds present in fairy shrimp.
Superoxide dismutase (SOD) is an enzyme involved in the fish antioxidant defense system, which protects cells from damage by reactive oxygen species (ROS). SOD is a key component of a fish’s antioxidant defense system [45]. It protects fish from stress-induced oxidative damage [50,51]. Hence, higher SOD activity indicates a stronger antioxidant defense capability. These findings indicated that higher inclusion levels of fairy shrimp meal in the diet enhance the antioxidant capacity of flowerhorn cichlids, likely due to the carotenoid content and other bioactive compounds present in fairy shrimp. This evaluated the activity of SOD as an indicator of the antioxidant response in flowerhorn cichlids fed different levels of fairy shrimp meal. The results demonstrated a significant increase in SOD activity in fish fed FS30 compared to the control group, while fish fed FS10 and FS20 exhibited a non-significant increase. The observed enhancement in SOD activity at higher dietary levels of fairy shrimp meal suggested an improved antioxidant defense system in flowerhorn cichlids, due to the high carotenoid content in fairy shrimp. The previous report demonstrated that the suitable level of carotenoids in the diet may increase SOD activity in Nile tilapia (Oreochromis niloticus) [52].
MDA levels, indicative of lipid peroxidation and oxidative stress, significantly reduced in fish fed FS30, with a decreasing trend observed in fish fed FS10 and FS20. Lipid peroxidation occurs in response to oxidative stress, giving rise to unsaturated aldehydes like malondialdehyde (MDA). MDA has been used to assess the effect of experimental stress induced in fish [53,54]. A lower MDA level reduces the oxidative damage to cellular membranes, further supporting the antioxidant potential of fairy shrimp meal. The results suggested that fairy shrimp meal supplementation enhanced the antioxidant defense system in flowerhorn cichlids, likely due to its high carotenoid content and bioactive compounds. The increased SOD activity and reduced MDA levels indicated that fairy shrimp meal effectively mitigated oxidative stress, contributing to improved fish health and physiological performance.
The inclusion of fairy shrimp in the diet of flowerhorn cichlids enhanced coloration, increased carotenoid pigment accumulation, stimulated antioxidant activity, and boosted the immune function. However, its widespread adoption as a pigmentation enhancer and immune-boosting feed additive requires economic feasibility considerations. The cost of using fairy shrimp as a replacement for fishmeal must be evaluated to determine its market affordability. The production costs of experimental diets containing 10–30% fairy shrimp were compared with the control diet. The results showed that the diet with the highest fairy shrimp inclusion (30%) had the highest production cost, reaching 24.08 EUR/kg. Currently, commercially available flowerhorn cichlid feed is priced at 30.86 EUR/kg (from a survey of market price). Therefore, using fairy shrimp as both a protein source and a natural pigmentation enhancer in ornamental fish feed is economically viable. A formulation containing 30% fairy shrimp, which yielded the most significant pigmentation enhancement and immune-stimulating effects, can be commercially produced at a cost-effective price while ensuring the profitability for manufacturers. Thus, incorporating fairy shrimp into pelleted diets for flowerhorn cichlids is a highly suitable approach that should be considered by feed producers and aquaculture enterprises. However, further research is recommended to comprehensively evaluate the formulated feed in comparison to commercial diets, particularly in terms of growth performance, pigmentation efficacy, and overall cost-effectiveness, to determine its practical applicability and economic viability.

5. Conclusions

The inclusion of fairy shrimp in the diet did not impact the growth performance, feed utilization, and nutritional composition of flowerhorn cichlids. Diets supplemented with fairy shrimp exhibited beneficial effects on skin coloration, body pigment accumulation, hematological parameters, and blood biochemical profiles. The antioxidant properties of fairy shrimp contributed to protective effects by enhancing the immune response of flowerhorn cichlids. Incorporating fairy shrimp into flowerhorn cichlid diets as a functional feed ingredient promoted resistance against oxidative stress and reduced the risk of disease occurrence.

Author Contributions

Conceptualization, W.T.; methodology, W.T. and P.W.; software, P.K.; validation, S.W. and N.S.; formal analysis, W.T. and P.W.; investigation, W.T. and P.W.; resources, S.W. and N.S.; data curation, S.W., N.S. and P.K.; writing—original draft preparation, W.T.; writing—review and editing, W.T. and P.W.; visualization, P.K.; supervision, W.T.; project administration, W.T.; funding acquisition, P.W. All authors have read and agreed to the published version of the manuscript.

Funding

This work was financially supported by Mahasarakham University, Maha Srakham, Thailand (Grant no. 1/2565).

Institutional Review Board Statement

Ethical approval for this study was obtained from the Ethics Committee of Mahasarakham University (approval ID: IACUC-MSU-04/2021, approval date: 9 April 2021). All experimental procedures and the fish research methodology were in accordance with the ethical guidelines of the Institute of Animals for Scientific Purposes Development of Thailand.

Data Availability Statement

Data are contained within the article.

Acknowledgments

This research project was financially supported by Mahasarakham University. We gratefully thank Khajonsak Pakting and Chatdanai Posri for their kind assistance during the preparation of this research.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Abe, H.A.; Reis, R.G.A.; Barros, F.A.L.; Paixão, P.E.G.; Meneses, J.O.; de Souza, J.C.N.; Fujimoto, R.Y. Optimal Management Improves Flowerhorn Fish Larviculture. Aquac. Res. 2021, 52, 2353–2358. [Google Scholar] [CrossRef]
  2. Hoseinifar, S.H.; Roosta, Z.; Hajimoradloo, A.; Vakili, F. The Effects of Lactobacillus acidophilus as Feed Supplement on Skin Mucosal Immune Parameters, Intestinal Microbiota, Stress Resistance and Growth Performance of Black Swordtail (Xiphophorus helleri). Fish Shellfish Immunol. 2015, 42, 533–538. [Google Scholar] [CrossRef] [PubMed]
  3. Jain, A.; Kaur, V.I.; Hollyappa, S.A. Effect of Dietary Supplementation of Carrot Meal on Survival, Growth and Pigmentation of Freshwater Ornamental Fish, Koi Carp, Cyprinus carpio (L.). Indian J. Anim. Nutr. 2019, 36, 405–413. [Google Scholar] [CrossRef]
  4. Manikandan, K.; Felix, N.; Prabu, E. A Review on the Application and Effect of Carotenoids with Respect to Canthaxanthin in the Culture of Fishes and Crustaceans. Int. J. Fish. Aquat. Stud. 2020, 8, 128–133. [Google Scholar] [CrossRef]
  5. Sathyaruban, S.; Uluwaduge, D.I.; Yohi, S.; Kuganathan, S. Potential natural carotenoid sources for the colouration of ornamental fish: A review. Aquac. Int. 2021, 29, 1507–1528. [Google Scholar] [CrossRef]
  6. Rapoport, A.; Guzhova, I.V.; Bernetti, L.; Buzzini, P.; Kieliszek, M.; Kot, A.M. Carotenoids and Some Other Pigments from Fungi and Yeasts. Metabolites 2021, 11, 92. [Google Scholar] [CrossRef]
  7. Khalil, A.; Tazeddinova, D.; Aljoumaa, K.; Kazhmukhanbetkyzy, Z.A.; Orazov, A.; Toshev, A.D. Carotenoids: Therapeutic Strategy in the Battle Against Viral Emerging Diseases, COVID-19: An Overview. Int. J. Food Sci. Nutr. 2021, 26, 241–261. [Google Scholar] [CrossRef]
  8. Dararat, W.; Lomthaisong, K.; Sanoamuang, L. Biochemical Composition of Three Fairy Shrimps (Branchiopoda: Anostraca) from Thailand. J. Crustac. Biol. 2012, 32, 81–87. [Google Scholar] [CrossRef]
  9. Velu, C.S.; Munuswamy, N. Nutritional Evaluation of Decapsulated Cysts of Fairy Shrimp (Streptocephalus dichotomus) for Ornamental Fish Larval Rearing. Aquac. Res. 2003, 34, 967–974. [Google Scholar] [CrossRef]
  10. Velu, C.S.; Munuswamy, N. Composition and Nutritional Efficacy of Adult Fairy Shrimp Streptocephalus dichotomus as Live Feed. Food Chem. 2007, 100, 1435–1442. [Google Scholar] [CrossRef]
  11. Saengphan, N.; Suksomnit, A.; Chaleoisak, P.; Chusing, R. Cultures of Fairy Shrimp (Streptocephalus sirindhornae) for Feeding Giant Freshwater Prawn (Macrobrachium rosenberbii). J. Agric. Technol. 2015, 11, 25–29. [Google Scholar]
  12. Sriputhorn, K.; Sanoamuang, L. Fairy Shrimp (Streptocephalus sirindhornae) as Live Feed Improve Growth and Carotenoid Contents of Giant Freshwater Prawn Macrobrachium rosenbergii. Int. J. Zool. Res. 2011, 7, 138–146. [Google Scholar] [CrossRef]
  13. Seidgar, M. The Effects of Fairy Shrimp Phallocryptus spinosa (Branchiopoda: Anostraca) as Live Food on Reproduction Performances and Color of Freshwater Ornamental Fish Prawns. Int. J. Aquat. Sci. 2015, 6, 37–44. [Google Scholar]
  14. Sornsupharp, S.; Dahms, H.U. Effect of Frozen Zooplankton Feed on Growth and Reproductive Performance of Crayfish (Procambarus clarkii). Int. J. Agric. Technol. 2017, 13, 2317–2324. [Google Scholar]
  15. Dararat, W.; Starkweather, P.L.; Sanoamuang, L. Life History of Three Fairy Shrimps (Branchiopoda: Anostraca) from Thailand. J. Crustac. Biol. 2011, 4, 623–629. [Google Scholar] [CrossRef]
  16. Sornsupharp, B.; Lomthaisong, K.; Dahms, H.U.; Sanoamuang, L. Effects of Dried Fairy Shrimp Streptocephalus sirindhornae Meal on Pigmentation and Carotenoid Deposition in Flowerhorn Cichlid; Amphilophus citrinellus (Gunther, 1864) × Cichlasoma trimaculatum (Gunther, 1867). Aquac. Res. 2013, 46, 173–184. [Google Scholar] [CrossRef]
  17. Pratama, I.; Albasri, H. Potential Development of Fairy Shrimp Streptocephalus spp. as Aquaculture Live Feed in Indonesia. Earth Environ. Sci. 2020, 521, 012026. [Google Scholar] [CrossRef]
  18. Sornsupharp, S.; Dahms, H.U.; Sanoamuang, L. Nutrient Composition of Fairy Shrimp Streptocephalus sirindhornae Nauplii as Live Food and Growth Performance of Giant Freshwater Prawn Postlarvae. Aquac. Nutr. 2013, 19, 349–359. [Google Scholar] [CrossRef]
  19. AOAC. Official Methods of Analysis of AOAC International, 16th ed.; AOAC International: Arlington, TX, USA, 1995. [Google Scholar]
  20. Sharma, G. Digital Color Imaging Handbook; CRC Press LLC: Washington, DC, USA, 2003; 764p. [Google Scholar]
  21. Rodriguez-Amaya, D.B.; Kimura, M. Harvestplus Handbook for Carotenoid Analysis; Harvest Plus Technical Monograph 2: Washington, DC, USA, 2004; pp. 1–63. [Google Scholar]
  22. Van Doan, H.; Wangkahart, E.; Thaimuangphol, W.; Panase, P.; Sutthi, N. Effects of Bacillus spp. Mixture on Growth, Immune Responses, Expression of Immune-Related Genes, and Resistance of Nile Tilapia Against Streptococcus agalactiae Infection. Probiotics Antimicrob. 2023, 15, 363–378. [Google Scholar] [CrossRef]
  23. Pulli, B.; Ali, M.; Forghani, R.; Schob, S.; Hsieh, K.L.; Wojtkiewicz, G.; Linnoila, J.J.; Chen, J.W. Measuring Myeloperoxidase Activity in Biological Samples. PLoS ONE 2013, 8, e67976. [Google Scholar] [CrossRef]
  24. Wangkahart, E.; Bruneel, B.; Chantiratikul, A.; De Jong, M.; Pakdeenarong, N.; Subramani, P.A. Optimum Dietary Sources and Levels of Selenium Improve Growth, Antioxidant Status, and Disease Resistance: Re-Evaluation in a Farmed Fish Species, Nile tilapia (Oreochromis niloticus). Fish Shellfish Immunol. 2022, 121, 172–182. [Google Scholar] [CrossRef] [PubMed]
  25. Sutthi, N.; Thaimuangphol, W.; Rodmongkoldee, M.; Leelapatra, W.; Panase, P. Growth Performances, Survival Rate, and Biochemical Parameters of Nile Tilapia (Oreochromis niloticus) Reared in Water Treated with Probiotic. Comp. Clin. Pathol. 2018, 27, 597–603. [Google Scholar] [CrossRef]
  26. Radhakrishnan, G.; Shivkumar, M.V.S.; Yashwanth, B.S.; Pinto, N.; Pradeep, A.; Prathik, M.R. Dietary protein requirement for maintenance, growth, and reproduction in fish: A review. J. Entomol. Zool. Stud. 2020, 8, 208–215. [Google Scholar]
  27. Maoka, T. Carotenoids as Natural Functional Pigments. J. Nat. Med. 2020, 74, 467–488. [Google Scholar] [CrossRef]
  28. Galasso, C.; Corinaldesi, C.; Sansone, C. Carotenoids from Marine Organisms: Biological Functions and Industrial Applications. Antioxidants 2017, 6, 96. [Google Scholar] [CrossRef]
  29. Srinoparatawatana, C.; Krueahong, J.; Prachumpon, S. Effect of Supplementation Thai Fairy Shrimp (Branchinella thailandensis) on Growth and Coloration of Gold Fish (Carassius auratus). Prawarun Agric. J. 2017, 14, 22–29. [Google Scholar]
  30. Sefc, K.M.; Brown, A.C.; Clotfelter, E.D. Carotenoid-Based Coloration in Cichlid Fishes. Comp. Biochem. Physiol. 2014, 173, 42–51. [Google Scholar] [CrossRef]
  31. Zhang, J.; Yang, Y.; Xu, H.; Li, X.; Dong, F.; Chen, Q.; Han, T.; Wang, J.; Wu, C. Effects of Dietary Astaxanthin on Growth Performance, Immunity, and Tissue Composition in Largemouth Bass, Micropterus salmoides. Front. Mar. Sci. 2024, 11, 1404661. [Google Scholar] [CrossRef]
  32. Shastak, Y.; Pelletier, W. Captivating Colors, Crucial Roles: Astaxanthin’s Antioxidant Impact on Fish Oxidative Stress and Reproductive Performance. Animals 2023, 13, 3357. [Google Scholar] [CrossRef]
  33. Reshi, Q.M.; Ahmed, I.; Al-Anazi, K.M.; Farah, M.A. Indexing Hematological and Serum Biochemical Reference Intervals of Himalayan Snow Trout, Schizothorax esocinus to Instrument in Health Assessment. Front. Physiol. 2023, 14, 989442. [Google Scholar] [CrossRef]
  34. Rastiannasab, A.; Afsharmanesh, S.; Rahimi, R.; Sharifian, I. Alternations in the Liver Enzymatic Activity of Common carp, Cyprinus carpio in response to parasites, Dactylogyrus spp. and Gyrodactylus spp. J. Parasit. Dis. 2016, 40, 1146–1149. [Google Scholar] [CrossRef] [PubMed]
  35. Rama, S.; Manjabhat, S.N. Protective Effect of Shrimp Carotenoids Against Ammonia Stress in Common Carp, Cyprinus carpio. Ecotoxicol. Environ. Saf. 2014, 107, 207–213. [Google Scholar] [CrossRef] [PubMed]
  36. Ajeniyi, S.A.; Solomon, R.J. Urea and Creatinine of Clarias Gariepinus in Three Different Commercial Ponds. Nat. Sci. 2014, 12, 124–138. [Google Scholar]
  37. Alfonso, S.; Fiocchi, E.; Toomey, L.; Boscarato, M.; Manfrin, A.; Dimitroglou, A.; Papaharisis, L.; Passabi, E.; Stefani, A.; Lembo, G.; et al. Comparative Analysis of Blood Protein Fractions in Two Mediterranean Farmed Fish: Dicentrarchus labrax and Sparus aurata. BMC Vet. Res. 2024, 20, 322. [Google Scholar] [CrossRef]
  38. Devaraj, A.; Justice, S.; Bakaletz, L.; Goodman, S. DNABII proteins play a central role in UPEC biofilm structure. Mol. Microbiol. 2024, 96, 1119–1135. [Google Scholar] [CrossRef]
  39. Esmaeili, N. Blood Performance: A New Formula for Fish Growth and Health. Biology 2021, 10, 1236. [Google Scholar] [CrossRef]
  40. Fazio, F. Fish Hematology Analysis as an Important Tool of Aquaculture: A Review, Aquaculture. Aquaculture 2019, 500, 237–242. [Google Scholar] [CrossRef]
  41. Sowmya, R.; Nm, S. Enhancement of Non-Specific Immune Responses in Common Carp, Cyprinus carpio, by Dietary Carotenoids Obtained from Shrimp Exoskeleton. Aqua. Rep. 2013, 46, 1562–1572. [Google Scholar] [CrossRef]
  42. Gopan, A.; Muralidhar, A.; Varghese, T.; Sahu, N.P. Dietary Carotenoid Supplementation Improves Fillet Appearance, Antioxidant Status and Immune responses in Striped Catfish (Pangasianodon hypophthalmus) Neverthless the Growth Performance. Turk. J. Fish. Aquat. Sci. 2018, 18, 1303–1313. [Google Scholar] [CrossRef]
  43. Khieokhajonkhet, A.; Roatboonsongsri, T.; Suwannalers, P.; Aeksiri, N.; Kaneko, G.; Ratanasut, K.; Inyawilert, W.; Phromkunthong, W. Effects of Dietary Supplementation of Turmeric (Curcuma longa) Extract on Growth, Feed and Nutrient Utilization, Coloration, Hematology, and Expression of Genes Related Immune Response in Goldfish (Carassius auratus). Aqua. Rep. 2023, 32, 101705. [Google Scholar] [CrossRef]
  44. Elashry, M.A.; Mohammady, E.Y.; Soaudy, M.R.; Ali, M.M.; El-Garhy, H.S.; Ragaza, J.A.; Hassaan, M.S. Growth, Health, and Immune Status of Nile tilapia Oreochromis niloticus Cultured at Different Stocking Rates and Fed Algal β-carotene. Aqua. Rep. 2024, 35, 101987. [Google Scholar] [CrossRef]
  45. Lim, K.C.; Yusoff, F.D.; Shariff, M.; Kamarudin, M.S.; Nagao, N. Dietary Supplementation of Astaxanthin Enhances Hemato-Biochemistry and Innate Immunity of Asian Seabass, Lates calcarifer (Bloch, 1790). Aquaculture 2019, 512, 734339. [Google Scholar] [CrossRef]
  46. Oliveira, J.; Oliva-Teles, A.; Couto, A. Tracking Biomarkers for the Health and Welfare of Aquaculture Fish. Fishes 2024, 9, 289. [Google Scholar] [CrossRef]
  47. Li, L.; Cardoso, J.C.R.; Félix, R.C.; Mateus, A.P.; Canário, A.V.M.; Power, D.M. Fish Lysozyme Gene Family Evolution and Divergent Function in Early Development. Dev. Comp. Immunol. 2021, 114, 103772. [Google Scholar] [CrossRef]
  48. Gan, Q.; Chi, H.; Dalmo, R.A.; Meng, X.; Tang, X.; Xing, J.; Sheng, X.; Zhan, W. Characterization of Myeloperoxidase and Its Contribution to Antimicrobial Effect on Extracellular Traps in Flounder (Paralichthys olivaceus). Front. Immunol. 2023, 14, 1124813. [Google Scholar] [CrossRef]
  49. Sattanathan, G.; Tamizhazhagan, V.; Padmapriya, S.; Liu, W.C.; Balasubramanian, B. Effect of Green Algae Chaetomorpha antennina Extract on Growth, Modulate Immunity, and Defenses against Edwardsiella tarda Infection in Labeo rohita. Animals 2020, 10, 2033. [Google Scholar] [CrossRef]
  50. Biswas, P.; Singh, S.K.; Debbarma, R.; Dey, A.; Waikhom, G.; Deb, S.; Patel, A.B. Effects of Carotenoid Supplementation on Colour, Growth and Physiological Function of the Dwarf Chameleon Fish (Badis badis). J. Anim. Physiol. Anim. Nutr. 2024, 108, 126–138. [Google Scholar] [CrossRef]
  51. Shi, Q.; Xiong, X.; Wen, Z.; Qin, C.; Li, R.; Zhang, Z.; Gong, Q.; Wu, X. Cu/Zn Superoxide Dismutase and Catalase of Yangtze Sturgeon, Acipenser dabryanus: Molecular Cloning, Tissue Distribution and Response to Fasting and Refeeding. Fishes 2022, 7, 35. [Google Scholar] [CrossRef]
  52. Panase, P.; Vongkampang, T.; Wangkahart, E.; Sutthi, N. Impacts of Astaxanthin-Enriched Paracoccus carotinifaciens on Growth, Immune Responses, and Reproduction Performance of Broodstock Nile Tilapia During Winter Season. Fish Physiol. Biochem. 2024, 50, 1205–1224. [Google Scholar] [CrossRef]
  53. Garcia, D.; Lima, D.; Humberto da Silva, D.G.; Alves de Almeida, E. Decreased Malondialdehyde Levels in Fish (Astyanax altiparanae) Exposed to Diesel: Evidence of Metabolism by Aldehyde Dehydrogenase in the Liver and Excretion in Water. Ecotoxicol. Environ. Saf. 2020, 190, 110107. [Google Scholar] [CrossRef]
  54. Rizzo, M. Measurement of Malondialdehyde as a Biomarker of Lipid Oxidation in Fish. Am. J. Anal. Chem. 2024, 15, 303–332. [Google Scholar] [CrossRef]
Figure 1. Lysozyme activity (U/mL) in flowerhorn cichlids fed different levels of fairy shrimp meal (FS). Different superscripts indicate significant differences (p < 0.05).
Figure 1. Lysozyme activity (U/mL) in flowerhorn cichlids fed different levels of fairy shrimp meal (FS). Different superscripts indicate significant differences (p < 0.05).
Fishes 10 00132 g001
Figure 2. Myeloperoxidase activity in flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
Figure 2. Myeloperoxidase activity in flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
Fishes 10 00132 g002
Figure 3. SOD activity in flowerhorn cichlids fed different levels of fairy shrimp meal (FS). Different superscripts indicate significant differences (p < 0.05).
Figure 3. SOD activity in flowerhorn cichlids fed different levels of fairy shrimp meal (FS). Different superscripts indicate significant differences (p < 0.05).
Fishes 10 00132 g003
Figure 4. Levels of malondialdehyde (MDA) in flowerhorn cichlids fed different levels of fairy shrimp meal (FS). Different superscripts indicate significant differences (p < 0.05).
Figure 4. Levels of malondialdehyde (MDA) in flowerhorn cichlids fed different levels of fairy shrimp meal (FS). Different superscripts indicate significant differences (p < 0.05).
Fishes 10 00132 g004
Table 1. Compositions of the experimental diets (dry matter basis g kg−1).
Table 1. Compositions of the experimental diets (dry matter basis g kg−1).
IngredientsControlFS10F20FS30
Fish meal32025017070
Soybean meal270180130110
Wheat flour90150180200
Corn meal150150150150
Squid liver meal50505050
Red yeast50505050
Soybean oil30303030
Squid liver oil25252525
Premix15151515
Dry fairy shrimp0100200300
Table 2. Growth performance and feed utilization of flowerhorn cichlids fed with different levels of fairy shrimp meal (FS).
Table 2. Growth performance and feed utilization of flowerhorn cichlids fed with different levels of fairy shrimp meal (FS).
ParameterFS0FS10FS20FS30p-Value
IW (g)19.10 ± 3.2818.88 ± 3.30 19.85 ± 2.30 19.23 ± 3.63 0.997
FW (g)21.88 ± 3.7121.27 ± 3.65 23.04 ± 2.76 22.66 ± 4.24 0.986
IL (cm)8.40 ± 1.41 8.32 ± 1.42 8.91 ± 1.01 8.41 ± 1.43 0.989
FL (cm)9.08 ± 1.52 8.82 ± 1.50 9.73 ± 1.109.11 ± 1.54 0.974
WG (g)2.77 ± 0.99 2.39 ± 0.693.19 ± 0.64 3.42 ± 0.74 0.794
ADG (g/day)0.05 ± 0.02 0.04 ± 0.01 0.06 ± 0.01 0.06 ± 0.01 0.794
SGR (%/day)0.18 ± 0.07 0.16 ± 0.05 0.22 ± 0.04 0.22 ± 0.05 0.843
FCR1.01 ± 0.17 1.02 ± 0.18 1.22 ± 0.15 1.04 ± 0.22 0.816
SR (%)100.00 ± 0.00 100.00 ± 0.00 100.00 ± 0.00 100.00 ± 0.00 -
Abbreviations: IW: initial weight; FW: final weight; IL: initial length; FL: final length; WG: weight gain; ADG: average daily gain; SGR: specific growth rate; FCR: feed conversion ratio; SR: survival rate. Values represent the mean ± SEM.
Table 3. Skin coloration of flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
Table 3. Skin coloration of flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
ParameterControlFS10F20FS30p-Value
Day 0
Lightness (L*)36.72 ± 1.27 37.08 ± 1.71 39.19 ± 0.56 37.30 ± 1.13 0.517
Redness (a*)4.79 ± 0.88 4.88 ± 0.34 4.29 ± 0.52 5.08 ± 0.66 0.834
Yellowness (b*)12.52 ± 1.19 11.85 ± 0.75 11.46 ± 0.68 11.39 ± 0.90 0.806
Hue (H°ab) 1.21 ± 0.05 1.17 ± 0.05 1.21 ± 0.05 1.15 ± 0.05 0.763
Chroma (C*)13.45 ± 1.36 12.86 ± 0.60 12.30 ± 0.59 12.54 ± 0.91 0.829
Day 60ControlFS10F20FS30p-Value
Lightness (L*)48.68 ± 1.9546.48 ± 0.88 47.52 ± 0.47 46.65 ± 0.88 0.548
Redness (a*)7.95 ± 0.70 c9.15 ± 0.60 b9.34 ± 0.50 b10.50 ± 1.15 a0.031
Yellowness (b*)14.33 ± 1.50 14.38 ± 1.48 12.57 ± 0.45 13.46 ± 0.63 0.634
Hue (H°ab) 1.06 ± 0.01 a1.00 ± 0.06 bc0.93 ± 0.02 c0.91 ± 0.04 c0.014
Chroma (C*)16.39 ± 1.64 17.18 ± 1.17 15.67 ± 0.40 17.11 ± 1.14 0.780
Values followed by different letters in the same row are significantly different (p < 0.05).
Table 4. Total carotenoid content (µg g−1) in the diet and fish fed different levels of fairy shrimp meal (FS).
Table 4. Total carotenoid content (µg g−1) in the diet and fish fed different levels of fairy shrimp meal (FS).
Total Carotenoids (µg g−1)FS0FS10FS20F30p-Value
Diet26.00 ± 5.86 c56.16 ± 6.61 b62.00 ± 7.32 b93.20 ± 6.00 a0.001
Fish8.87 ± 0.65 c15.26 ± 0.78 b17.94 ± 1.27 b22.81 ± 1.23 a0.000
Values followed by different letters in the same row are significantly different (p < 0.05).
Table 5. Proximate analysis of the experimental diets (% dry matter basis).
Table 5. Proximate analysis of the experimental diets (% dry matter basis).
CompositionControlFS10F20FS30p-Value
Crude protein40.25 ± 0.0639.93 ± 0.03 39.98 ± 0.27 40.20 ± 0.04 0.337
Crude lipid3.17 ± 0.08 3.20 ± 0.09 3.28 ± 0.13 3.37 ± 0.20 0.073
Moisture10.30 ± 0.02 10.33 ± 0.16 10.11 ± 0.03 10.22 ± 0.05 0.325
Ash4.61 ± 0.06 4.98 ± 0.19 4.69 ± 0.04 4.82 ± 0.01 0.130
Fiber1.16 ± 0.03 1.15 ± 0.01 1.14 ± 0.01 1.17 ± 0.02 0.722
NFE40.50 ± 0.04 40.41 ± 0.30 40.78 ± 0.26 40.22 ± 0.21 0.416
Energy
(Kcal/100 g)
430.06 ± 0.69 428.06 ± 1.80 430.66 ± 1.04 430.52 ± 1.34 0.492
GE (MJ/kg)17.89 ± 0.02 17.81 ± 0.07 17.92 ± 0.04 17.91 ± 0.05 0.477
Abbreviations: NFE: nitrogen-free extract; GE: gross energy calculated based on 23.67, 39.54, and 17.57 kJ/g protein, lipid, and carbohydrates, respectively.
Table 6. Proximate analysis of the fillet of flowerhorn cichlids fed different levels of fairy shrimp meal (FS) (% dry matter basis).
Table 6. Proximate analysis of the fillet of flowerhorn cichlids fed different levels of fairy shrimp meal (FS) (% dry matter basis).
CompositionControlFS10F20FS30p-Value
Crude protein74.97 ± 0.2175.31 ± 0.26 75.34 ± 0.17 75.49 ± 0.02 0.337
Crude lipid11.29 ± 0.24 11.36 ± 0.08 11.42 ± 0.03 11.52 ± 0.08 0.636
Moisture4.28 ± 0.02 4.27 ± 0.03 4.34 ± 0.05 4.40 ± 0.04 0.125
Ash4.64 ± 0.05 4.68 ± 0.07 4.55 ± 0.01 4.66 ± 0.06 0.362
Table 7. Blood biochemical analysis of flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
Table 7. Blood biochemical analysis of flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
Blood AnalysisControlFS10FS20FS30p-Value
ALT (SGPT) (U/L)29.33 ± 1.76 a28.00 ± 3.79 a24.00 ± 0.58 a11.67 ± 0.88 b0.002
AST (SGOT) (U/L)93.00 ± 3.21 a90.00 ± 6.08 a82.33 ± 1.76 a43.33 ± 4.63 b0.000
BUN (mg/dL)3.33 ± 0.33 2.67 ± 0.33 3.00 ± 0.002.67 ± 0.33 0.363
Alkaline15.33 ± 0.33 a13.33 ± 0.67 ab10.67 ± 0.33 b12.33 ± 1.20 ab0.012
Total protein (g/dL)2.47 ± 0.032.77 ± 0.032.73 ± 0.072.93 ± 0.180.053
Albumin (g/dL)0.93 ± 0.03 1.00 ± 0.00 0.97 ± 0.03 1.03 ± 0.03 0.162
Globulin (g/dL) 1.53 ± 0.031.77 ± 0.031.77 ± 0.031.90 ± 0.150.07
Cholesterol (mg/dL)128.33 ± 1.20 139.00 ± 5.51 133.33 ± 4.06 137.67 ± 6.06 0.406
Values followed by different letters in the same row are significantly different (p < 0.05).
Table 8. Hematological analysis of flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
Table 8. Hematological analysis of flowerhorn cichlids fed different levels of fairy shrimp meal (FS).
HematologyControlFS10FS20FS30p-Value
RBCs (×106 cells/mm3)0.30 ± 0.03 b0.34 ± 0.07 b0.85 ± 0.09 a1.04 ± 0.19 a0.019
Hemoglobin (g/dL−1)2.38 ± 0.08 b2.45 ± 0.15 b3.95 ± 0.35 a4.30 ± 0.00 a0.004
Hematocrit (%)7.25 ± 0.25 b7.50 ± 0.50 b12.00 ± 1.00 a13.00 ± 0.00 a0.004
WBCs (cells/mm3)2007.50 ± 27.50 b2035.00 ± 55.00 b3040.00 ± 175.00 a3475.00 ± 110.00 a0.001
Neutrophils (%)41.00 ± 1.00 b42.25 ± 3.00 b62.25 ± 2.00 a65.00 ± 0.50 a0.001
Eosinophils (%)1.25 ± 0.25 1.25 ± 0.25 1.00 ± 0.00 1.75 ± 0.25 0.242
Lymphocytes (%)56.50 ± 1.50 a55.00 ± 3.00 a31.00 ± 2.00 b33.5 ± 0.50 b0.001
Monocytes (%)1.25 ± 0.25 1.50 ± 0.50 3.00 ± 0.00 2.50 ± 0.50 0.081
Abbreviations: RBCs: red blood cells; WBCs: white blood cells. Values followed by different letters in the same row are significantly different (p < 0.05).
Table 9. Economic analysis of diets containing different levels of fairy shrimp meal.
Table 9. Economic analysis of diets containing different levels of fairy shrimp meal.
IngredientsPrice
(THB/kg)
FS0FS10FS20FS30
AmountCostAmountCostAmountCostAmountCost
Fish meal400.3212.800.2510.000.176.800.072.80
Soybean meal150.274.050.182.700.131.950.111.65
Wheat flour150.091.350.152.250.182.700.203.00
Corn meal110.151.650.151.650.151.650.151.65
Squid liver320.051.600.051.600.051.600.051.60
Red yeast25000.05125.000.05125.000.05125.000.05125.00
Soybean oil350.031.050.031.050.031.050.031.05
Squid liver oil1380.033.450.033.450.033.450.033.45
Premix 2000.023.000.023.000.023.000.023.00
Fairy shrimp meal (FS)20000.000.000.10200.000.20400.000.30600.00
Diet price (THB/kg)153.95350.70547.20743.20
Diet price (EUR/kg)4.9911.3617.7324.08
ECR (kg/fish; THB)155.49357.71667.58772.93
ECR (kg/fish; EUR)5.0411.5921.6325.05
EUR 1 = THB 35 (5/1/2025); diet price of flowerhorn cichlid in the market = 1080 THB/kg (30.86 EUR/kg).
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Weber, P.; Wigraiboon, S.; Sutthi, N.; Kasamesiri, P.; Thaimuangphol, W. The Physiological Benefits and Economic Value of Using Fairy Shrimp as Fish Meal for Flowerhorn Cichlids; Amphilophus citrinellus (Günther, 1864) × Cichlasoma trimaculatum (Günther, 1867). Fishes 2025, 10, 132. https://doi.org/10.3390/fishes10030132

AMA Style

Weber P, Wigraiboon S, Sutthi N, Kasamesiri P, Thaimuangphol W. The Physiological Benefits and Economic Value of Using Fairy Shrimp as Fish Meal for Flowerhorn Cichlids; Amphilophus citrinellus (Günther, 1864) × Cichlasoma trimaculatum (Günther, 1867). Fishes. 2025; 10(3):132. https://doi.org/10.3390/fishes10030132

Chicago/Turabian Style

Weber, Ploychompoo, Supranee Wigraiboon, Nantaporn Sutthi, Pattira Kasamesiri, and Wipavee Thaimuangphol. 2025. "The Physiological Benefits and Economic Value of Using Fairy Shrimp as Fish Meal for Flowerhorn Cichlids; Amphilophus citrinellus (Günther, 1864) × Cichlasoma trimaculatum (Günther, 1867)" Fishes 10, no. 3: 132. https://doi.org/10.3390/fishes10030132

APA Style

Weber, P., Wigraiboon, S., Sutthi, N., Kasamesiri, P., & Thaimuangphol, W. (2025). The Physiological Benefits and Economic Value of Using Fairy Shrimp as Fish Meal for Flowerhorn Cichlids; Amphilophus citrinellus (Günther, 1864) × Cichlasoma trimaculatum (Günther, 1867). Fishes, 10(3), 132. https://doi.org/10.3390/fishes10030132

Article Metrics

Back to TopTop