Niloticus Fingerlings Research Articles

Effect of stocking density on growth performance, survival and production of Monosex Tilapia (Oreochromis niloticus) under nursery ponds in northern regions of Bangladesh

The present study was to assess and evaluate the culture potential of Tengra with short-cycle species in the seasonal water bodies of farmers’ fields and disseminate the cultural technologies in a different part of the country. The research study was evaluating the improvement of nursery management technique in drought prone area of Northern region in farmer field level. Before conducting research fish farmers of Different upazila were selected by departmental authority and pre training management. Growth, survival and production performances of Oreochromis niloticus fingerlings were evaluated for 40 days in nine nursery ponds having an area of 20 decimal each with an average depth of 1.0 m. Three stocking densities such as 1000 dec-1 (T1=Treatment-1), 1200 dec-1 (T2= Treatment-2) and 1400 dec-1 (T3=Treatment-3) were tested with three replications. Fry were fed with commercial nursery feed (30% crude protein). The rate of feeding was 25% to 8% of the estimated body weight of fry. The physico-chemical and biological parameters of pond water were within the suitable range for fish culture. Growth in terms of final weight, final length, weight gain, length gain and specific growth rate was significantly higher in T1 than those obtained from T2 and T3. The survival of fish fingerlings was higher in T1(85.67%) than T3 (76%) and T2 (83%) respectively. Maximum of fingerlings was produced in T2 than those in T1 and T3. Among the treatments evaluated, 1000 dec-1 was the best stocking density considering the growth performance of the fingerlings of monosex Tilapia, O. niloticus in nursery ponds.

Impacts of substituting fish meal with full-fat or defatted black soldier fly (Hermetia illucens) larvae on growth, quality, and health of Nile tilapia (Oreochromis niloticus) fingerlings

This study investigated the use of black soldier fly (Hermetia illucens) larvae (BSFL), provided in either full-fat (FBSF) or defatted (DBSF) forms, as an alternative protein source in the diet of Nile tilapia (Oreochromis niloticus) fingerlings. Specifically, the influence was assessed of BSFL on growth performance, hematological parameters, body composition, and histology. Nine diets (including the control) were formulated to be isonitrogenous (35 % crude protein) and isolipidic (6 % crude lipid), relying on fish meal as the primary protein source and gradually replacing it with BSFL meal at levels of 25 %, 50 %, 75 %, or 100 % on an equivalent protein basis, corresponding to dietary inclusion levels of 5.25 %, 10.25 %, 15.5 %, and 20.0 %, respectively. Fish with an initial mean weight ± standard deviation of 1.3 ± 0.26 g were fed for 12 weeks until the fish final weight was in the range 24.08–34.95 g. Based on the results, there were no significant (p>0.05) differences in the growth performance or feed conversion ratios among the treatments. Additionally, there were no significant differences in the hematological responses or the proximate body composition. Furthermore, 100 % substitution of fish meal with FSFL and DBSF meal caused blood congestion in the hepatopancreas region and several intraepithelial leukocytes in the intestine. There were no detrimental impacts at levels of 25 %, 50 %, and 75 % on growth performance, hematological responses, body composition, or the intestines or liver histological characteristics of the O. niloticus fingerlings. This information should provide useful guidance for the management of Nile tilapia, an economically important species.

Acute toxicity of Oreochromis niloticus fingerlings exposed to effluent from Delta State University, Abraka Nigeria boys hostel

Studies on aquatic pollution are crucial for maintaining environmental health. This study assessed the toxicity of effluents from the male hostel site II at Delta State University (DELSU) on Oreochromis niloticus fingerlings. Behavioral responses and mortality rates were observed as toxicity indicators. The physicochemical characteristics of the raw effluent were evaluated and compared with standard methods. In a 96-hour static bioassay, 20 fingerlings were exposed to varying effluent concentrations: 0%, 20%, 40%, 60%, 80%, and 100%, with the experiment triplicated. Analysis showed pH (5.6), temperature (26.1°C), TDS (304 mg/L), dissolved oxygen (5.7 mg/L), chlorine (5.55 mg/L), ammonia (0.21 mg/L), and hardness (0.79 mg/L). Water analysis over 12-96 hours ranged for pH (5.45-5.62), temperature (22.50-26.30°C), TDS (61.50-237.50 mg/L), DO (4.45-6.00 mg/L), chlorine (0.84-3.98 mg/L), ammonia (0.14-0.37 mg/L), and hardness (6.52-31.93 mg/L), with no statistically significant differences (p>0.05). Behavioral responses included air gulping, irregular swimming, and lack of reflex. Mortality depended on effluent concentration, with no deaths at 0%-80% but 80% mortality at 100%. Lethal times for 50% and 95% mortality at 100% concentration were 48.6 and 102.8 hours, respectively. Diluting or treating wastewater before release is necessary to prevent fish mortality in the wild.

Biosecurity protocols and fish health management in Kenyan fish hatcheries: a key to sustainable production of quality fish seed

Aquaculture, or aquafarming, is increasingly becoming a vital farming activity globally to meet exponentially high demand for fish and reduce pressure on global capture fisheries. In Kenya, aquaculture growth has led to concerns over the supply of quality fish seed, with farmers often reporting involving fingerling adulteration and mislabelling where frog tadpoles are packed and supplied as Clarias gariepinus fingerlings and mixed-sex Oreochromis niloticus fingerlings are falsely sold to fish farmers as sex-reversed monosex Nile tilapia. This study aims to identify strategies to enhance the quality of fish seed production in the country. Primary data were collected via questionnaires and interviews using the Kobo toolbox. Respondents were selected through purposive and random sampling. The SPSS software was used for the analysis. Findings showed moderate reliance on specific reporting offices for fish disease cases and significant variation in disease types and bio security measures. Fish disease treatment and management practices were more engaged by hatchery operators than disease reporting. No significant differences were found between disease treatment and management, type of fish diseases encountered at the hatchery, and the nature of fingerlings produced (p > 0.05). However, there was a significant difference between the source of broodstock, biosecurity measures, type of fish diseases encountered, and the Disease Case Reporting Office (p < 0.05). No significant difference was found between biosecurity measures and the period when the hatchery was established (p > 0.05). Lack of financial support, inexperienced workforce, and a lack of knowledge in fish disease identification and treatment were the major problems affecting the sustainability of hatchery operations in the country. Aquaculture policymakers should establish financial support for hatcheries, implement disease management training, promote research collaborations for disease surveillance, and incentivize biosecurity measures among hatchery managers and farmers to improve aquaculture sustainability in Kenya. Further research should explore treatment methods and long-term sustainability to mitigate disease risks.

Effectiveness of feeding different biochars on growth, digestibility, body composition, hematology and mineral status of the Nile tilapia, Oreochromis niloticus

Oreochromis niloticus fingerlings (5.15 ± 0.02 g; n = 315) were fed with different types of biochar (BC)-supplemented sunflower meal-based (SFM) diet to investigate the effects of various BC inclusions on their nutritional digestibility, body composition, hematology and mineral status for 60 days. Seven different diets were formulated based on the SFM based diet: one was a control (TD-I, CON) and the other six diets were supplemented with 2% BC derived from different sources. These BCs were derived from the following: cotton stick (CSBC, TD-II), wheat straw (WSBC, TD-III), corn cob (CCBC, TD-IV), house waste (HWBC, TD-V), grass waste (GWBC, TD-VI), and green waste (GwBC, TD-VII) biochar. There were three replicates for each test diet. Each tank had fifteen tilapia fingerlings, and they were fed with 5% of their live wet weight and twice daily. The outcomes showed that the supplementation of CCBC significantly elevated the growth, nutrient absorption, and body composition of the O. niloticus fingerlings (p < 0.05); with concomitant lowering of the quantity of nutrients released into the water bodies whereas HWBC gave negative impacts. The maximal mineral absorption efficiency (Ca, Na, K, Cu, Fe, P, and Zn) was achieved by the supplementation of 2% CCBC. All hematological parameters showed positive improvements (p < 0.05) with CCBC. Interestingly, CCBC significantly improved the growth, digestibility, body composition, hematology, and mineral status of O. niloticus.

The effect of dietary administration of Saussurea lappa root on performance, blood biochemical indices, redox status, innate immune response, intestinal microbial population and resistance against A. hydrophila infections of Tilapia Fingerlings.

This experiment was performed to identify the influence of dietary Saussurea lappa root (SLR) on the performance and general health status of Nile Tilapia fingerlings (O. niloticus). Four formulated diets with different SLR levels of 0.0, 2.5, 5 and 10 g/kg, respectively, were afforded to fingerling fish (15.42 ± 0.05 g) for 8 weeks. The feed efficiency ratio (FER), feed intake (FI) and feed conversion ratio varied with dietary SLR level in a linear model and a high feed efficiency rate was recorded at the 10 g/kg group, while FI and FCR exhibited an opposite trend (P < 0.001). Dietary SLR level influenced serum protein constituents, liver and renal function enzymes, triglycerides, cholesterol and glucose (P < 0.001). Serum Catalase (CAT), total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) remarkedly increased with dietary SLR level and attained a level at 10 g/kg. Furthermore, serum lysozyme, complement C3 (C3), IgA and IgD were stimulated by 10 g/kg SLR. Intestinal digestive enzymes (lipase and amylase) increased with SLR level up to 10 g/kg. As the dietary SLR level raised, the cumulative survival percentage aginst A. hydrophila challenge increased and then reached a maximum at 10 g/kg SLR group. Moreover, gene expression of pro-inflammation cytokines (TNF-2a, IL-1β, and IL-10) in liver and kidney transcriptomes demonstrated effective immunostimulant capabilities of greater SLR inclusion levels in fish diet. Meanwhile, intestinal microbial investigation, revealed that high levels of SLR in tilapia fish feed significantly suppressed total bacterial count, and pathogenic bacterial count (such as, E. coli, Coliform, Aeromonas spp, Pseudomonas spp.), and stimulated lactic acid bacteria development. Finally, it is recommended to include a high level of SLR (5 or 10 g/kg) in the diet of O. niloticus fingerlings to enhance feed efficiency, antioxidant characteristics, and immunological response against bacterial infections.

Selenium‐chitosan engineered nanocomposite as efficient formulated fish diet evaluated for sustainable aquaculture practice of Oreochromis niloticus (Nile tilapia) fishes

AbstractOreochromis niloticus a Nile tilapia fish is widely used for fish culture practice in many countries for its easy acclimatization and high yield at a short pace of time. Selenium‐chitosan (SeCh) nanoparticles are efficiently used in agriculture, medicine, and aquaculture practices in several studies. The significant approach of Selenium‐Chitosan incorporated fish feed will be evaluated in the present study to achieve the better aquaculture practice in future. In the present study, SeCh nanoparticle was chemically synthesized and incorporated with formulated fish feed. Selenium formulated fish feed contains 31.49 g of carbohydrates and 41.52 g of proteins. SeCh‐fed O. niloticus fingerlings exhibited significantly increased specific growth rates in terms of weight gain, and feed conversion ratio. Chemical characterization of SeChNPs through FTIR spectroscopy indicates the presence of an adjuvant combination of selenium and chitosan presence through functional groups of COO stretch, CH, CC, and CN stretch representing at 3226, 2878, and 1734 cm−1, respectively. Scanning electron microscopy (SEM) and EDX analysis revealed the structural properties of SeChNPs as a fibrous pattern that contains Carbon, Oxygen, and Selenium elements as predominant peak values. SeChNPs incorporated fish feed has higher protein content which is a standard hallmark for a fish feed and an essential prerequisite for fish growth. The formulated SeCh fish feed in the present study is an innovative approach which can be taken further for higher level testing and processing for developing as a better fish feed in terms of feasible and efficient fish growth enhancer.

The effects of dietary Spirulina platensis or curcumin nanoparticles on performance, body chemical composition, blood biochemical, digestive enzyme, antioxidant and immune activities of Oreochromis niloticus fingerlings

ContextRecently, prioritize has been given to using natural phytogenic or nano compounds as growth promoters and immunostimulants in fish diets as an alternative to antibiotics.AimsThe main propose of this trial was to determine the impact of supplementing diets with spirulina or curcumin nanoparticles on the performance and health indicators of Nile tilapia fingerlings.MethodsIn a 56-day feeding trial, 180 tilapia fingerlings were assigned into three main groups, as follows: 1st, control group, 2nd, Spirulina platensis (SP; 5 g kg-1 diet) and 3rd, curcumin nanoparticles (CUR-NPs; 30 mg kg-1 diet).Key resultsIncorporating tilapia diets with SP or CUR-NPs significantly improved performance, body chemical analysis, blood biochemical and hematological indices, digestive enzyme activities, and antioxidant and immunostimulant features compared to the control.ConclusionFortified tilapia diets with CUR-NPs or SP efficiently boost the productivity and health of Nile tilapia fingerlings.ImplicationsThe research introduces new practical solutions for applying safe feed additives as alternatives to antibiotics in tilapia farming.

Effects of Supplementation of Insoluble Dietary Fiber Obtained from Cinnamon Spent Bark Waste on the Performance of Nile Tilapia (&lt;em&gt;Oreochromis niloticus&lt;/em&gt;) Fingerlings

Dietary fiber supplementation has proven benefits on fish health and growth. Cinnamon spent bark waste is the cinnamon bark residue after oil distillation. It is a rich source of insoluble dietary fiber with very low contents of soluble dietary fiber. This study aimed to investigate the potential of using water-extracted insoluble fiber from cinnamon spent bark waste as a functional ingredient in the diets of Oreochromis niloticus fingerlings. Four experimental diets were prepared by replacing a commercial feed with extracted dietary fiber at 0 (control), 0.5%, 1%, and 1.5% levels. Fingerlings of O. niloticus were assigned to the four experimental diets and the feeding trial was conducted for 12 weeks. The results revealed that the weight gain, specific growth rate, feed conversion ratio, Fulton’s condition factor, and survival rate of fish were not significantly different among the experimental groups. Fiber supplementation at 1.5% significantly increased (p&lt;0.05) the total aerobic bacteria population in feces, whereas the coliform counts in feces at 0.5% and 1% fiber supplementation were significantly lower (p&lt;0.05) than the control. There was a significant increase (p&lt;0.05) in red blood cells count at 0.5% fiber supplementation. Moreover, insoluble dietary fiber supplementation significantly (p&lt;0.05) increased the white blood cell counts in blood. Results suggested that insoluble fiber supplementation affected gut microbial populations and blood parameters of O. niloticus fingerlings. However, further investigations on gut microbiology and hematology are needed to ensure the use of insoluble dietary fiber from cinnamon spent bark waste as a functional ingredient in the diets of O. niloticus fingerlings.

Effects of processed duckweed (Lemna paucicostata) meals as protein sources in Oreochromis niloticus (Linnaeus, 1758) diets

Effects of processed duckweed meals as a replacement for toasted soybean meal in the diets of Oreochromis niloticus fingerlings were evaluated. Sun-dried and blanched duckweed meals were used to replaced toasted soybean meal in at 25, 50, 75, and 100% each. Feed Solution Software (version 2022) was used to formulate nine iso-nitrogenous diets at 32% crude protein. 27 Hapa nets of 1 m2 each were used for the feeding trials for six months. Ten fingerlings of Oreochromis niloticus were stocked per Hapa and fed 5% body weight three times per day. The best mean weight gain (460.59 g), viscerosomatic index (9.90) and feed conversion ratio (1.82) were recorded in the fish fed 75% blanched duckweed meal while the fish fed 100% sun-dried duckweed meal and 100% blanched duckweed meal recorded the poor mean weight gain, viscerosomatic index and feed conversion ratio of 401.69 g and 394.03 g, 6.49 and 6.36, 2.06 and 2.10, respectively. The cost-benefit evaluation revealed that 75% blanched duckweed meal gave the highest net profit (₦3,682) and lowest incident cost (₦6.49). This study revealed that soybean meal can be replaced with 75% blanched duckweed meal in the diet of Oreochromis niloticus without any inauspicious effects on the growth and nutrient utilization, and will reduce the cost of production and maximize profit.

Sustainability of Growth Performance, Water Quality, and Productivity of Nile Tilapia-Spinach Affected by Feeding and Fasting Regimes in Nutrient Film Technique-Based Aquaponics

Aquaponic systems offer an innovative approach to sustainable agriculture, where the interplay between fish and plant cultivation can be optimized. The choice of feeding and fasting schedules plays a crucial role in system efficiency and overall productivity. This study aims to investigate the impacts of various feeding and fasting schedules on water quality, and the growth performance of Nile tilapia, Oreochromis niloticus fingerlings, and spinach productivity in an aquaponic system based on the nutrient film technique (NFT). O. niloticus fingerlings with an initial weight of 13.47 ± 0.14 g were randomly stocked at a density of 6 kg/m3, and spinach plants (Spinacia oleracea) were included. The study employed a completely randomized block design with five replications. Various water quality parameters were monitored, and the effects of different feeding/fasting schedules on fish and spinach were assessed. The data revealed significant differences (p &lt; 0.05) in water quality parameters, all of which remained within acceptable ranges for aquaponic systems. The one-day feeding/one-day fasting treatment resulted in reduced final body weight, weight gain percentage, and specific growth rate, compared to other treatment groups (p &lt; 0.05). Higher levels of glucose and plasma cortisol were observed in this treatment. Economic efficiency was highest in the daily feeding treatment (40.05%), with no statistical difference (p &gt; 0.05) observed in the group subjected to three-day feeding/one-day fasting (39.03%). Spinach yield varied significantly between treatments (p &lt; 0.05), with the daily feeding treatment recording the highest yield (2.78 kg/m2) and the one-day feeding/one-day fasting cycle having the lowest yield (1.57 kg/m2). The findings suggest that the three-day feeding/one-day fasting regime in an NFT-based aquaponic system results in efficient nutrient utilization, higher productivity, and profitability for Nile tilapia. Additionally, this approach supports marketable biomass production for spinach. Different feeding and fasting schedules have distinct effects on water quality, fish growth, and spinach productivity in aquaponic systems. The three-day feeding/one-day fasting schedule emerges as an effective strategy for optimizing resource utilization and increasing overall productivity.

The Potential of Whole Soya Bean Meal in Raising Nile Tilapia (Oreochromis Niloticus, L.) Fingerlings

An eight-week experimental study was undertaken to determine the effect of whole soya bean meal (SBM) with reference to common fish feed ingredients, consisting of Omena (Rastineobola argentea) meal (RAM), Freshwater shrimp (Caridina niloticus) meal (CNM) and commercial fish meal (CFM, control diet) on water quality, growth performance and survival of O. niloticus fingerlings.

Evaluation of fermented soybean meal by Bacillus subtilis as an alternative to fishmeal on the growth, and physiological status of Nile tilapia Oreochromis niloticus fingerlings

A feeding trial was conducted to investigate the effect of fermented soybean meal with Bacillus subtilis bacteria on growth performance, feed utilization, carcass composition, and hematological, and histological section of the liver and intestine of Nile tilapia Oreochromis niloticus fingerlings. Commercial soybean meal (SBM) containing 44% Crude Protein (CP) was fermented using the solid-state fermentation method which depended on autoclaving of SBM, then bacterial treatment injection by Bacillus subtilis, and finally incubation at 40C for 72 h then autoclaved to stop the growth of bacteria. Five isonitrogenous (25% crude protein) and isocaloric (4.4 kcal\\g gross energy) experimental fish meal-free diets were formulated to compare with a common control diet containing fishmeal and unfermented soybean meal. Diets without fish meal contain fermented soybean meal (FSM) as a sole protein, FSM with corn gluten (CG), FSM with free amino acid methionine (Meth), FSM with corn gluten and methionine, and unfermented soybean meal. Eighteen glass aquaria, 80-L net volume, were used to stock 10 fingerlings (10.0 ± 0.1 g/fish) in each aquarium in the replicates group. The feed amount was given three times daily, six days a week throughout the 98 days experimental period. Fish were weighed biweekly and feed amounts were adjusted based on the new fish weight. Bacterial fermentation enhanced the protein content of commercial soybean meals by 6%. The crude protein of fermented soybean meal increased from 43.44% to 50.67%. Used of FSM as a sole dietary protein source resulted in a decrease in growth rate and feed utilization. However, the incorporation of FSM with corn gluten, and/or methionine amino acid led to an improvement in the performance of fish. Finally, the best final body weight, weight gain, specific growth rate, protein efficiency ratio, and protein productive value were recorded by a fish-fed mixed plant protein diet (FSM + CG + Meth). Also, Hematocrit and red blood cells were not significantly affected including the FSM.

Air-breathing Behaviour in Heterotis niloticus Fingerlings: Response to Changes in Oxygen, Temperature and Exercise Regimes.

Air-breathing in fish is believed to have arisen as an adaptation to aquatic hypoxia. Although air-breathing has been widely studied in numerous fish species, little is known about the obligate air-breathing African bonytongue, Heterotis niloticus. In this way, we evaluated if abiotic factors and physical activity affect air-breathing patterns in fingerlings. The air-breathing frequency (fAB ) and behavioural responses of H. niloticus fingerlings were assessed in response to environmental oxygen, temperature, and exhaustion and activity in a series of experiments. The air-breathing behaviour of H. niloticus fingerlings under optimum water conditions was characterised by swift excursions lasting less than 1 s to the air-water interface to gulp air. The intervals between air-breaths were highly variable, ranging from 3 to 259s. Body size only slightly affected fAB , while hypoxia, hyperthermia, and exercise stress significantly increased fAB . Progressive hypoxia from 17.69 to 2.17 kPa caused a ~2.5 fold increase in fAB . Increasing temperatures to 27 and 32°C, from a baseline temperature of 22°C, significantly increased fAB from 0.4 ± 0.2 to 1.3 ± 0.5 and 1.6 ± 0.4 breaths min-1 , respectively. Lastly, following exhaustive exercise, fAB increased up to 3-fold. These observations suggest that H. niloticus fingerlings are very reliant on aerial oxygen, and their air-breathing behaviour is sensitive to environmental changes and activity levels.

Effects of water additive probiotic, Pediococcus acidilactici on growth performance, feed utilization, hematology, gene expression and disease resistance against Aspergillus flavus of Nile tilapia (Oreochromis niloticus)

Probiotics are live beneficial Micro-organism introduced into the gastrointestinal tract through food or water, probiotics confer several benefits and play important roles in improving growth performances, disease resistance, immunity, health status, gut microbiome, and water quality. The present study examined the effects of water additive probiotic, Pediococcus acidilactici, on growth performance, feed utilization, hematology, gene expression, and disease resistance in tilapia Oreochromis niloticus fingerlings challenged with fungus (Aspergillus flavus). Triplicate groups of Nile tilapia fingerlings (20.0 ± 0.4 g) were fed a commercial diet in four water treatments control (0 g/m3), 0.1PA (0.1 g//m3), 0.2PA (0.2 g/m3) and 0.3PA (0.3 g/m3) of P. acidilactici respectively. The water quality parameters particularly total ammonia nitrogen (TAN) and ammonia (NH3) decreased significantly (P ≤ 0.05) in all three water treatments 0.3PA treatment was the lowest) when compared to the control treatment. The highest significant values (P ≤ 0.05) of growth performance, feed utilization and hematology recorded of either 0.2PA or 0.3PA group, in addition, the expression of innate immune genes were significantly upregulated (P ≤ 0.05) of tilapia fingerling at 0.3PA group compared to the control. The results also showed that juveniles reared in three water treatments with additive probiotics had a significantly lower (P ≤ 0.05) mortality when challenged with Aspergillus flavus. Hence, the water additive probiotic used in this study is a promising solution as an alternative product to improve the water quality, growth, and health of O. niloticus.

Profitability of Using Five Different Commercial Tilapia Starter Feeds on the Ghanaian Market in Nile Tilapia, Oreochromis niloticus Fingerlings Production

Choice and use of fish feed should not only depend on good fish growth but also, on higher returns on investment. Growth performance and cost-effectiveness of five tilapia starter feeds (Aller Aqua, ARDECFeed, Koudijs, Naam Papa and Raanan) to produce Nile tilapia, Oreochromis niloticus fingerlings were investigated. The feeds, with crude protein (CP) contents ranging from 42.0 to 60.0%, were randomly coded A, B, C, D and E. The study was conducted in fifteen fine mesh net hapas, each of dimensions 5.0x2.0x1.2 m, installed in three 0.2-hectare earthen ponds with each containing a replicate of each feed type. Nile tilapia fry, ranging from 0.05 to 0.08 g with an initial mean weight of 0.06±0.01 g were stocked at 500 fry hapa-1 and they were fed at 20.0% of their biomass; three times daily. The feeding rate was reduced to 10% when the fry attained mean weights ranging from 1.0 to 5.0 g and finally to 5.0% when they were greater than 5.0 g. The feeding trial lasted for nine weeks (63 days). Fry final mean weight ranged from 17.34±9.12 to 23.62±14.39 g, with B being significantly higher (Tukey`s HSDT, P&lt;0.05) whilst there were no significant differences (ANOVA, P&gt;0.05) among A, C, D and E. The profit indices ranged from 4.13±0.55 to 14.63±0.38, with D being the highest and B, the least. Hence, tilapia hatchery operators should opt for feeds that give higher profit indices, lower production and incidence costs for fingerlings production.

Impact of Different Concentration of Thorn Apple (Datura stramonium) Extract on Growth, Histopathology and Blood Profiles Response to Sub- Lethal Exposure of Nile Tilapia (Oreochromis niloticus) Juveniles

This study investigated the toxic effects of Datura stramonium leaves extract on growth, histopathology and blood profiles of Oreochromis niloticus juveniles. Datura stramonium leaves extract of various concentrations were prepared at 0.00 (control), 0.002, 0.02 and 0.2 ml/L for 28 days and 10 days withdrawal in triplicate. Twenty (20) Oreochromis niloticus fingerlings (6.05±0.01g) were randomly distributed into each experimental bowl containing 45 L of treatment concentrations. Biological evaluation, blood profiles parameters, and histology of the exposed fish were determined. The result shows an increase within the weight gain and the weight gain was higher in the exposed groups expect TAL 4 than the control. There was no significant difference (P&gt;0.05) among the treatments. The haematological response to D. stramonium exposures shows that the values of packed cell volume and haemoglobin were higher in the exposed groups compared to the control while the white blood cell, neutrophils, and lymphocytes decrease as the concentration of the plant increases and were lower than the control. The result revealed a higher value of total protein and albumin in the exposed groups compared to the control. There were decreased in the values of ALT and AST when compared to the control and the values of total protein, albumin, ALT and AST after 10 days of withdrawal show a similar trend in values obtained before the experiment. The result of histopathology shows no observable lesions were observed in control group while there were moderate alterations in gills, liver and the intestine of the exposed groups. This investigation revealed that continuous use of the D. stramonium leaves extract in the aquatic environment will affects the growth, blood profiles and histopathology of the exposed fish.

Physiological and immunological responses of Nile tilapia fed dietary supplementation of sweet basil ethanolic and aqueous extracts

The use of phytotherapy in aquaculture is rapidly increasing for more environmentally sustainable measures. The present work aimed to investigate the effects of different dietary levels of sweet basil, Ocimum basilicum, leaves ethanol (BEE) or aqueous (BAE) extracts (0, 200, 300, and 500 mg/kg) on Oreochromis niloticus growth, digestive enzyme activities, hemato-biochemical profile, antioxidant status, immune responses, and resistance against Streptococcus agalactiae. Oreochromis niloticus fingerlings (40.00 ± 1.00 g/fish, n = 210) were randomly divided into seven triplicated groups (control, BEE200, BEE300, BEE500, BAE200, BAE300, and BAE500) and fed the experimental diets for 8 weeks. The results revealed that dietary inclusion of BEE and BAE significantly improved final weight, weight gain, survival, and digestive enzyme activities. The growth response revealed a dose-dependent in favor of fish fed BEE. The hemato-biochemical biomarkers showed a significant improvement in RBCs, WBCs, hemoglobin, and lymphocyte, and a significant decrease in aminotransferases, creatinine, and cholesterol levels with dietary basil extracts. The cellular and humoral immune responses (phagocytic activity, phagocytic index, lysozyme activity, immunoglobulin) were significantly improved with increasing BEE and BAE in a dose-dependent manner. The expression of IL-1β and TNF-α genes were increased, while TGF-β was decreased in a dose-dependent manner and BEE500 have the highest expression. The antioxidant balance was improved with increasing basil extracts supplementation, and the BEE500 group showed the best antioxidant status. Dietary BEE and BAE increased Nile tilapia resistance to S. agalactiae. In conclusion, the dietary supplementation of both ethanolic and aqueous extracts could improve the growth performance and physiological, and immune-antioxidant status of Nile tilapia.

Behavioural Response of Oreochromis niloticus Fingerlings Exposed to Sub-Lethal Concentrations of Imidacloprid

Imidacloprid, a neonicotinoid pesticide that was once thought to be a solution to environmental pollution caused by previous pesticides like organophosphates and organochlorines has raised global concern recently. The present study aimed at assessing the effect of Imidacloprid on the behaviour of a commercially important fish species, Oreochromis niloticus. The study involved a 48 h sub-lethal toxicity test which was carried out with 0, 5, 10, 20, and 40 ppm of Imidacloprid. Fingerlings of O. niloticus weighing between 18 and 32g were exposed to these concentrations in a static bioassay with continuous aeration. Regular observation of the clinical signs revealed that fish exposed to higher concentrations of Imidacloprid displayed behavioural abnormalities such as erratic behaviour, respiratory stress, and irregular nervousness. The findings of this study revealed that Imidacloprid is toxic and causes behavioural distress on O. niloticus fingerlings. Therefore, there is urgent need for further studies to determine safe limit of Imidacloprid and other pesticides in the environment. Unregulated disposal of toxic pesticides should be avoided, to ensure human safety and environmental sustainability.

New Insights into the Effectiveness of Fungi-Degraded Date Pits Supplemented Diet on the Physiological and Biological Indices of Oreochromis niloticus Fingerlings

New Insights into the Effectiveness of Fungi-Degraded Date Pits Supplemented Diet on the Physiological and Biological Indices of Oreochromis niloticus Fingerlings