Academic literature on the topic 'Tilapia – Feed additives'

This study was performed to determine the effects of the extracts of two alternative antimicrobial agents that do not harm the ecosystem (rosemary, Rosmarinus officinalis and aloe vera, Aloe barbadensis) when added to the feed of tilapia (Oreochromis niloticus) on the growth performance, proximate composition, and biometric characteristics. Rosemary extract was added to the experimental diet in ratios of 0.1%, 0.25%, and 0.5% while aloe vera extract was added to the experimental diet in ratios of 0.5%, 1%, and 2.5%. After 90 days of the feeding trial, no change was seen in the weight increase, specific growth rate, feed conversion ratio, condition factor, hepatosomatic index, or viscerosomatic index of the tilapia. The fact that proximate analyses did not differ between groups showed that the plant extracts did not adversely affect the health status of tilapia in the ratios used in this study. As a result, the addition of 0.1%, 0.25%, and 0.5% rosemary extract and the addition of 0.5%, 1%, and 2.5% aloe vera extract to tilapia feeds did not cause changes in the growth performance, biometric indexes, or chemical composition findings of the fish meat.

Objective: This study was undertaken to evaluate the potential role of Mannan oligosaccharides (MOS) on growth performance, liver and intestine tissue morphology, and gut microbiota of Nile tilapia (Oreochromis niloticus). Design: Controlled study. Animals: Three groups of Nile tilapia. Procedures: Three diets were formulated to contain 0 % of MOS 500 (MOS) as control (control), 0.05% of MOS plus adding MOS into water as well at level of 12.5 mg/l (MOS (feed +water), and the third group MOS was added only to water (MOS water) at the same level, and fed to Nile tilapia for 6 weeks. Results: Simultaneous water and feed additives with (MOS feed+water) at (0.05% of feed + 12.5 mg/l water) caused a significant increase in growth parameters (initial and final weight, weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR) and condition factor (k), when compared to both MOS added only in tank water (MOS water) and control groups. In addition, MOS in both treatment types increased survival rates significantly compared to the control. Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) analysis showed that a single species or species that contained chemically equivalent DNA dominated the intestinal tract of all Nile tilapia regardless of dietary treatment. While MOS had no adverse effect of intestinal histology, an increase in the villi length was recorded. Conclusion and clinical relevance: Collectively, our results indicate that MOS added to feed and water could be used to enhance the growth performances, increase the survivability and exert beneficial effects on the gut microbiota of Nile tilapia.

This study aimed to evaluate the impact of plant-based food additives on growth performance, body composition and survival of Nile tilapia. Four isonitrogenous (25% CP) and isolipidic (13% CL) experimental diets were prepared and designated as R1, R2, R3, and R4. R1 contains (3% Cymbopogon citratus), R2 contains (3% Ocimum basilicum), R3 contains (3% Mentha spicata) and R4 (control or 0% additive). 180 Nile tilapia fry with an initial average weight of 0.2g were distributed in 12 plastic tanks (50 L/tank) at the stocking density of 15 fish per tank in an isolated system. Fish were fed with experimental diets 3 times per day (8:00 am, 1:00 pm and 5 :00 pm) for 3 months. After 90 days of experiment, the results revealed that the final average weight ranged from 2.62g to 8.00g, the absolute average weight gain (AAWG) from 2.42 to 7.8g, the feed conversion ratio (FCR) from 1.31 to 2.67 and specific growth rate (SGR) from 3.06 to 4.36%/d. The survival rate (SR) varied between 64 and 100%. Of the parameters studied such as the absolute average weight gain (AAWG), the specific growth rate (SGR), the feed conversion ratio (FCR), and the survival rate, the best were obtained by the group of fish fed with the R2 diet containing 3% Ocimum basilicum. The results of the analysis of the flesh showed that the addition of 3% O. basilicum does not modify the contents of dry matter, crude protein, and ash but slightly increased the fat content. Based on the results, the inclusion of natural plant-based food additive (3% Ocimum basilicum) in the diet of Nile tilapia improved the parameters of growth, feed efficiency, and survival.

Abstract Tilapia (Oreochromis sp) is the one commodity that very popular in the public. Besides low cost, good taste, protein content is also high. Feed is an element that is very supportive in an aquaculture operations. The main raw material in the artificial feed is fish meal and soy flour because it has a high protein content but is relatively expensive so it needs an alternative feed material. The purpose of this study is improve knowledge and skilled about feeding alternative production of vegetable waste and its effect on the growth of black tilapia. Study was conducted in Freshwater Aquaculture Management Unit which located in Kepanjen District, Malang Regency, Province of East Java started from January 20th until February 14th 2014. Work method which used was descriptive method by collecting primary data and secondary data. The data was collected by active participation, observation, interviewing, and study paper. The process of making feed alternative vegetable waste composed by several stage is preparation tools and materials, counting materials, production additives, blending, mixing, fermentation, and storage. The results of the evaluation of growth black tilapia feeding vegetable wastes little slow because of the low protein content

Modern technologies of industrial fish farming allow getting high-quality products. However, stressful conditions of an artificial ecosystem (high planting density, violation of optimal hydrochemical conditions) can negatively affect food activity, growth rate, lead to the development of alimentary diseases and depletion of the antioxidant potential In conditions when fish is deprived of natural food, and the metabolism is completely under human control, the use of balanced feeds enriched with macro — and microelements, as well as biologically active substances, maximizes metabolic processes and helps to increase the growth rate and obtain physiologically complete juveniles. The use of antioxidant feed additives allows not only to carry out timely therapy, but also to provide a preventive effect to prevent the negative consequences of an artificial ecosystem. Currently, there are a number of antioxidant feed additives, among which are of particular interest to natural bioantioxidant of flavonoid nature, such as catechins, dihydrochalcones, flavonols, leukocyanins, dihydroquercetin. The article discusses the experience of using a new generation antioxidant — dihydroquercetin and an immunostimulator — arabinogalactan in feeding a tilapia hybrid (Oreochromis mossambicus × Oreochromis niloticus). It was found that the addition of dihydroquercetin (25,0– 50,0 mg/kg) and arabinogalactan (50,0 mg/kg) to the production feed allowed to increase productivity by 26,0%, as well as to show a positive effect on the physiological state of fish. The results obtained complement the existing ideas about the fields of application of antioxidants, and also prove the prospects of using plant-based products as antioxidant feed additives.

We performed an 8-week feeding trial to evaluate dietary soluble extract hydrolysates from fishery by-products, such as shrimp soluble extract (SSE) with or without inosine monophosphate (IMP), tilapia soluble extract (TSE) and squid soluble extract (SQSE), in juvenile Nile tilapia. A diet without feed additives was used as the control diet (CON); and five other experimental diets were formulated with 2% soluble extracts consisting of 100% SSE, 98% SSE + 2% IMP (SSEP2), 96% SSE + 4% IMP (SSEP4), 100% SQSE and 100% TSE. The diets were fed to 4.9 ± 0.07 g (mean ± SD) juvenile Nile tilapia in triplicate groups. The weight gain and specific growth rates of fish fed the SSE, SSEP2 and SSEP4 diets were significantly higher than those of fish fed the CON and SQSE diets. The superoxide dismutase activity levels of fish fed the SSE and SSEP4 diets were significantly higher than those of fish fed the CON, SSEP2, SQSE and TSE diets. Myeloperoxidase activity levels of fish fed the SSE and SSEP4 diets were significantly higher than those of fish fed the CON, SSEP2 and SQSE diets. Lysozyme activity levels of fish fed the SSEP4 and SQSE diets were significantly higher than those of fish fed the SSE and SSEP2 diets. Feed efficiency, protein efficiency ratio, survival rate, whole body proximate composition and hematological parameters were not significantly different among the groups. After ten days of challenge = against Aeromonas hydrophila, the cumulative survival rate of fish fed the SSE diet was significantly higher than those of fish fed the CON, SQSE and TSE diets. In conclusion, dietary shrimp soluble extract could improve the growth performance, non-specific immune responses and disease resistance in juvenile Nile tilapia, and inosine monophosphate did not add further benefits to this ingredient.

AbstractThe present study evaluated the effects of dietary microbial phytase on the growth and gut health of hybrid tilapia (Oreochromis niloticus♀×Oreochromis aureus♂), focusing on the effect on intestinal histology, adhesive microbiota and expression of immune-related cytokine genes. Tilapia were fed either control diet or diet supplemented with microbial phytase (1000 U/kg). Each diet was randomly assigned to four groups of fish reared in cages (3×3×2 m). After 12 weeks of feeding, weight gain and feed conversion ratio of tilapia were not significantly improved by dietary microbial phytase supplementation. However, significantly higher level of P content in the scales, tighter and more regular intestinal mucosa folds were observed in the microbial phytase group and the microvilli density was significantly increased. The adhesive gut bacterial communities were strikingly altered by microbial phytase supplementation (0·41<similarity coefficient<0·54). Stimulated intestinal inflammation and stress status were observed in the fish fed diet supplemented with microbial phytase, as indicated by the up-regulated intestinal expressions of the cytokine genes (tnf-αandtgf-β) andhsp70. In addition, the gut microvilli height was significantly decreased in the phytase group. These results indicate that dietary microbial phytase may exert mixed effects on hybrid tilapia, and can guide our future selection of phytases as aquafeed additives – that is, eliminating those that can stimulate intestinal inflammation.

Thesis (PhD)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: This study investigated the “Effect of Phytogenic Feed Additives on Gonadal Development in Mozambique tilapia (Oreochromis mossambicus). Aquaculture remains the fastest growing animal food-producing sector and it is set to overtake capture fisheries as a source of food fish, and also to outpace population growth. This rapid growth can be attributed to the increasing demand for aquaculture products, and an urgent need for a sustainable food resource and the safe production of food. Globally, fish provides over 3.5 billion people with up to 15 percent of their average per capita intake of animal protein. The introduction of aquaculture to sub-Saharan African (SSA) took place during the 1940s and 1950s, and the main objectives were to improve nutrition in rural areas, allow for the diversification of activities to reduce the risk of crop failures, to generate additional income, and to create employment opportunities. Aquaculture was seen as a viable option for rural development in SSA, and substantial resources were invested to support its development. Poor results were however, recorded in terms of production and sustainability. Tilapia is the most widely cultured of all fish species farmed, and the second most important group of freshwater and brackish water fish after carps. Tilapia has all the necessary traits that makes it an excellent species to culture, but costefficient production is hampered by the animals attaining sexual maturity at a an early age, which then result in precocious breeding in aquaculture systems. The production of single-sex populations (i.e. all male) is a potential means to address the problem of precocious breeding, but the technologies used to establish single-sex populations are not readily available to resource-poor communities that farm with tilapia for food purposes. Phytochemicals, also known as phytoestrogens, are plant-derived compounds that structurally or functionally mimic mammalian estrogens that affect the sexual differentiation of fish. Phytochemicals occur in plants like Pawpaw (Carica papaya) and Moringa (Moringa oleifera). The study thus had a threefold objective. Firstly, the study investigated the potential of Pawpaw seed meal (P) and Moringa seed meal (M), as part of a commercial tilapia diet, to be used as endocrine disrupting compounds (EDC’s) to control the reproduction of sexually mature Mozambique tilapia (20-45g). Secondly, assess the potential of P and M to inhibit the attainment of sexual maturity in immature tilapia (2-8g). Finally, P and M to determine its influence on sexual differentiation of tilapia fry (9-12 days posthatch) to produce all-male populations. The study indicated that both P and M seeds contain bio-active chemicals that are capable of disrupting the gonad function, differentiation and sexual maturation of Mozambique tilapia. Sperm production was affected, evident in the degeneration of the testicular tissue samples. Egg production, ovulation and spawning were all affected, as evident in the difference in colour of the degrading eggs, as well as the absence of spawning. Ovo-testes were observed in cases where diets containing 10.0g P and 10.0g M /kg basal diet were fed. Eggs were observed in the ovaries of sexually immature fish, but spawning did not occur. The study also presents the first report on the isolation of Oleanolic acid in Moringa seeds. The evident of antifertility properties of both Pawpaw and Moringa seeds can be exploited to control or prevent reproduction of Mozambique tilapia in SSA aquaculture systems. This could be of particular importance to aquaculture development in rural areas of Sub-Saharan African countries, given the abundant year round availability of these compounds. Further studies are required to optimise the preparation of the experimental compounds; as well as determining the optimal inclusion level of the phytogenic compounds, as well as how their efficacy to manipulate the reproductive potential and ability of Mozambique tilapia are influenced by environmental factors such as water temperature.
AFRIKAANSE OPSOMMING: Akwakultuur is die vinnigste groeiende dierlike voedsel-sektor. Daar word verwag dat dit visserye sal oortref as ʼn bron van voedsel en dat groei in dié bedryf selfs die bevolkingsgroei sal verbysteek. Die vinnige groei in die sektor kan toegeskryf word aan die toenemende vraag na akwakultuur produkte en 'n dringende behoefte vir 'n volhoubare voedsel hulpbron, wat ook die veilige produksie van voedsel sal verseker. Wêreldwyd voed vis meer as 3.5 miljard mense en dra tot 15% van die gemiddelde hoeveelheid dierlike proteïen per kapita ingeneem, by. Die bekendstelling van akwakultuur in sub-Sahara Afrika (SSA) het gedurende die 1940's en 1950's plaasgevind, met die belangrikste doelwitte om voeding in landelike gebiede te verbeter, geleenthede vir diversifisering te skep wat die risiko van misoeste verminder, om bykomende inkomste te genereer en werksgeleenthede te skep. Akwakultuur is gesien as 'n lewensvatbare opsie vir die ontwikkeling van die landelike gebiede in SSA en aansienlike hulpbronne is belê om die ontwikkeling daarvan te ondersteun. Swak resultate is egter in terme van produksie en volhoubaarheid behaal. Tilapia is die mees algemene spesies wat gekweek word en is die tweede mees belangrike groep van varswater en brak water vis soesies, na Karp. Tilapia beskik oor al die nodige eienskappe wat dit ʼn uitstekende spesie vir voedselproduksie maak, maar koste-doeltreffende produksie daarvan word gekortwiek deur die feit dat die spesie seksuele volwassenheid op 'n vroeë ouderdom bereik, wat dan lei tot vroeg-rype teling en die gevolglike oorbevolking en swak groei van tilapia in ʼn akwakultuur sisteem. Die produksie van enkel-geslag bevolkings (d.i. slegs manlike vis) is ʼn potensiële oplossing vir dié probleme, maar die tegnologie wat gebruik word om enkel-geslag bevolkings te produseer is nie geredelik toeganklik vir hulpbron-arme gemeenskappe wat met Tilapia vir kosdoeleindes boer nie. Fitochemikalieë, anders ook bekend as fito-estrogene, is verbindings wat in plante voorkom en wat struktureel of funksioneel die werking van die natuurlike soogdier estrogene/androgene naboots, met die fitochemikalieë wat die seksuele differensiasie van vis beïnvloed. Fitochemikalieë kom in plante soos papaja (Carica papaya) en Moringa (Moringa oleifera) voor. Die studie het dus gepoog om die potensiaal van papaja saad meel (P) en Moringa saad meel (M), as deel van 'n kommersiële tilapia dieet, om as endokriene ontwrigters (EDC's) gebruik te word om die reproduksie van seksueel volwasse Mosambiek tilapia (20-45g) te beheer, om te voorkom dat onvolwasse tilapia (2-8g) geslagsrypheid te vroeg bereik en ook om die geslagsdifferensiasie van tilapia vingerlinge (9-12 dae na uitkom) te manipuleer om enkel-geslag (manlike) produksiegroepe te produseer. Die studie het aangedui dat beide papaja en Moringa sade bio-aktiewe chemikalieë wat die werking van die gonadotrofien hormone, geslagsdifferensiasie die stadium waarop Mosambiek tilapia geslagsrypheid bereik, kan beïnvloed. Spermproduksie is negatief beïnvloed, soos waargeneem in die degenerasie van die testisweefsel. Eierproduksie, ovulasie en die vrystelling van eiers is almal negatief beïnvloed, soos duidelik waargeneem in die kleurverskil (van normale eiers) van eiers wat ʼn mate van reabsorbsie aandui en die feit dat geen eiers vrygestel is nie. Ovo-testes is waargeneem in gevalle waar diëte met 10.0g papaja en / of Moringa / kg basale dieet gevoer is. Eiers is waargeneem in die eierstokke van seksueel onvolwasse vis, maar vrystelling het nie plaasgevind nie. Die studie is die eerste verslag oor die isolasie van Oleanoliese suur in Moringa sade. Die duidelike reproduksie-beperkende (anti-vrugbaarheid) eienskappe van beide papaja en Moringa sade kan benut kan word om reproduksie in Mosambiek tilapia te voorkom of te manipuleer in SSA akwakultuur stelsels. Dit is veral van besondere belang vir akwakultuur ontwikkeling in die landelike gebiede van SSA lande, gegewe dat beide sade regdeur die jaar geredelik beskikbaar is. Verdere studies word benodig om protokolle vir die voorbereiding van die eksperimentele verbindings te optimaliseer, sowel as die bepaling van die optimale insluitingsvlakke van die fitogeniese verbindings, asook hoe die doeltreffendheid van hierdie verbindings deur omgewingsfaktore soos water temperatuur beïnvloed word.
The University for Development Studies (UDS), Ghana, particularly Prof S.K. Nokoe, and Ghana Education Trust Fund (GETFund), for the initial financial support that enabled me to enrol for the programme. The Division of Aquaculture, together with the Postgraduate and International Office (Postgraduate Funding Section), Stellenbosch University (SU) for financial support during my studies.

Three investigations were conducted to assess the effects of selected bio-active feed additives on tilapia (Oreochromis niloticus) growth performance, feed utilisation, haemato-immunological status, intestinal morphology and microbiology. The first experiment was conducted to evaluate the effects of feeding tilapia semi-practical diets supplemented with exogenous enzymes (phytase, protease or carbohydrase). After six weeks of the dietary supplementation, tilapia fed diets supplemented with exogenous enzymes (phytase and carbohydrase) showed enhanced growth performance and higher microvilli density when compared to the control group. Additionally, the intestinal bacterial community profile of tilapia fed the carbohydrase supplemented diet was significantly altered in contrast to those fed the control diet. In the second experiment, tilapia were fed with practical diets supplemented with exogenous enzymes (phytase, protease or xylanase) for eight weeks. Tilapia fed the xylanase supplemented diet demonstrated significantly higher final body weight (FBW), improved feed conversion ratio (FCR) and better protein efficiency ratio (PER) when compared to the control group. Apparent digestibility coefficients of protein, ash, energy, phosphorus, calcium and sodium were highest in tilapia fed a diet supplemented with phytase. The third experiment was carried out to assess the combined effects of dietary exogenous enzymes (phytase, protease and xylanase) and probiotics (Bacillus subtilis, B. licheniformis and B. pumilus) on tilapia growth performance and health. After seven weeks of feeding, tilapia fed the diet supplemented with both exogenous enzymes and probiotics showed significantly higher FBW, specific growth rate, improved FCR and better PER. The serum lysozyme activity was observed to be significantly higher in tilapia fed the probiotic supplemented diet when compared to the control group. The dietary supplementation with combined exogenous enzymes and probiotics increased intestinal perimeter ratio, microvilli count (density), diameter and subsequently resulted in higher enterocyte absorptive area in tilapia. This study demonstrates that feeding tilapia with dietary exogenous enzymes can enhance growth performance and modulate microbial community profile. In addition, supplementation with both exogenous enzymes and probiotics is capable of improving tilapia growth performance, immune parameters and intestinal morphology.

Experiments were conducted to evaluate the ability of prebiotic and probiotic supplementation of commercial fish feed to improve the physiological, immunological, and growth responses of stressed Nile tilapia. To investigate these objectives, tilapia were divided in two major groups: control fish (fed regular commercial feed) and stressed fish (induced by dietary cortisol supplemented to regular commercial feed). Stressed fish were further divided into three sub-groups: stressed fish fed regular feed, stressed fish fed probiotic-supplemented feed, and stressed fish fed a mixture of prebiotic and probiotic supplemented feed. Fish were maintained and tested over an eight-week long experimental period. A variety of physiological, immunological, and growth parameters were measured over the course of the experimental period. These parameters include: serum cortisol, blood glucose, plasma protein, packed cell volume, hepato-somatic index (HSI), spleen-somatic index (SSI), lysozyme activity, feed conversion ratio (FCR), specific growth rate (SGR), protein efficiency ratio (PER), length gain, weight gain, length gain, and condition factor (K). The results of this study does not support the use of these specific prebiotic and probiotic as functional feed additives in Nile tilapia at the levels tested in this study. Further research is needed to determine which probiotic species are best suited for use in Nile tilapia and which prebiotic, when used in combination, will allow these probiotics to have maximum effect.