Growth perfomance of Tilapia sparmanni fed on formulated chicken feeds

Growth performance of 120 fi sh fi ngerlings of Tilapia sparmanni stocked in three rectangular tanks was evaluated after feeding on three different formulated chicken feeds for eight weeks. Fish wet weights and lengths were measured after every two weeks, they indicated considerable increase. Positive correlation between mean wet weight increase and percentage increase in lipid and carbohydrate contents (r=0.9861; d.f=1; 0.1 < P < 0.2 and r=0.3312; d.f=1; P > 0.5) was noted respectively. A strong positive correlation r=0.9997; d.f=1; 0.002 < P < 0.05 with increase in mean wet weight was also observed for fi sh fed diet with relatively the highest % protein contents. Each diet type recorded different food conversion ratio, where F < 9.1339; d. f=6; 0.01 < P < 0.025. Therefore, diet type one was recommended because growth performance of T. sparmanni was the highest when compared to performance of the other two feeds. Research Article Growth perfomance of Tilapia sparmanni fed on formulated chicken feeds Nsinda Philemon1* and Tamatamah Rashid2 1Tanzania Fisheries Research Institute, PO Box 46, Shirati, Tanzania 2Department of Marine and Aquatic Sciences, University of Dar esalaam, Dar esalaam, Tanzania Received: 24 October, 2019 Accepted: 19 November, 2019 Published: 20 November, 2019 *Corresponding author: Nsinda Philemon, Tanzania Fisheries Research Institute, PO Box 46, Shirati, Tanzania, E-mail:


Introduction
Over half a billion people (workers and dependents) are wholly or partly supported by fi sheries, aquaculture and related industries [1]. Of which 95% are in developing countries where aquaculture is on the rise [2]. Demand for fi sh for food and recreation in these countries have also increased tremendously in the last few decades. Resulting into attempts to improve yield of useful aquatic organism through input of labour and energy Reay, 1979. Improved yield in aquaculture will be however, achieved by deliberate manipulation of fi sh growth rate, reduction of fi sh mortality and increased reproduction of fi sh. For example, in 1990, aquaculture contributed more than 10% of the world fi shery production [3]. Beside this direct contribution to dietary intake, fi sh contributed to household food security indirectly through increasing household income, which can be utilized to purchase other food commodities including lower cost staple foods [4][5][6]. Like any other form of animal production, yield of fi sh per unit area depends largely on the quality and quantity of food available to the animal. In this case, additional of external food source is regarded as direct and effi cient way of increasing food availability.
Most popular farmed species in Tanzania are Tilapiines and African catfi sh [7]. Tilapia especially T. sparmanni are well distributed in the southern and central regions of the country. Majority fi sh farmers use fertilizers from animal manure. The manures in use are; cow dung, sheep, poultry and rabbit manure, which increase the risk of introduction of pathogens into the system [8,9]. There is however, many chicken feed factories, which produce feeds that can as well can be used to feed fi sh in aquaculture sector.
For stance the rapid rise and growth of aquaculture in the major producing countries has been, in part, due to the availability of on-farm provision of feed inputs [10]. These feeds are prepared in both dry and non-dry forms. Dry fi sh feeds are normally made from dry ingredients, but they are not completely free from moisture. They just reach an equilibrium moisture contents (usually about 7.13%) depending on environment [11]. Dry diets are more suited for use with automatic feeders and generally more suitable in water causing less pollution. A further benefi t is that, processing techniques used in the manufacture of dry diets reduces the chance of transmitting diseases through contaminated feeds [12]. These observations explain why dry feeds are widely used for the cultivation of tilapia and other fresh water fi shes. It should be noted that the advantages of a dry food would be lost if there was a serious reduction in growth or food conversion effi ciency.
Fish feeds may be supplied as "supplementary" or complete'. Supplementary feeds are the additional feeds to the natural food available in the aquatic system. It is an important feed in tilapia culture for improving production. Most supplementary feeds are successful in large-scale culture of tilapia, but few are carried out in a systematic manner. Complete feeds are necessary in intensive systems of aquaculture where natural food is either absent or the proportion of natural food availability is small in relation to the total food requirements. Fertilization is another means of increasing food quantity to aquaculture system. They are applied in form of organic fertilizers (usually manufactured from factories) and inorganic fertilizers, the most suitable in terms of nutritional effi ciently.
The main purpose of these fertilizers is to provide fi sh with DOI: https://dx.doi.org/10.17352/2455-8400.000048 primary source of food. Fish growth is often determined by nutritional, and environmental factors. This paper examines the suitability of three different types of formulated chicken feeds were examined in terms of promoting growth of farm reared Tilapia sparmanni. It is well known in Tanzania that chicken feeds are readily available when compared to imported fi sh feeds. These chicken feeds are analysed relative to their contribution percentage of carbohydrates, proteins and lipids of the diet for promoting fi sh growth; best with low food conversion effi ciency; and fi nally, a suitable diet for farmed T.
sparmanni will be suggest.

Study area
The study on tilapia feeds was conducted at science laboratories of the University of Dar es salaam. Tilapia was chosen because is among the most popular farmed species in Tanzania followed by African catfi sh [7]. Tilapia sparmanni was chosen among the tilapiines due to its widely distribution Fish fi ngerlings were acclimatized for two days in rearing tank before feeding them with the three types of chicken formulated feeds presented in table 1.
Stocking density was 7 fi sh/m 2 and were fed 10% of their total body weights. This feeding ratio was adopted from Mohammed, et al., [13], as indicated in table 2. In addition, basic guideline of feeding tilapia where a mature fi sh consumes 1% of their body weight a day, while fi ngerlings consuming as much as 7% was applied.
The stocked fi sh initial mean weights were 6.3±2.3 g for the 1 st tank, 6.0±3.1 g for 2 nd tank, and 6.4±1.2 g for the 3 rd tank. Initial fi sh weights and lengths were measured using an electronic weighing balance (Oertling, OB152), and a ruler respectively. Fish were scooped and measured consistently every two weeks throughout the study. Water was virtually static and levels were constantly maintained in the tanks by replacing water loss through sampling and evaporation with equal volume of the un-carbonated tap water. Tanks were cleaned once per week to reduce contamination which might cause infections from food remains and oxygen depletion leading to possible disease outbreak. Temperature and pH were recorded using thermometer and a Digital min-pH-METERrespectively.

Data analysis
Data was analysed in stages. Food analysis was conducted to determine the % of carbohydrates, lipids, and proteins in the three formulated chicken feeds. Then randomised block ANOVA was used to test the effect of diet types on growth of fi sh. While

Discussion
In aquaculture, feeds account for 60 per cent of the production costs [14]. The most expensive ingredient in the diet of fi sh is the animal protein component. But in natural environment fi sh consumes an array of food, which change seasonally with size or age of fi sh. This guarantees adequate representation of the complex series of proteins, lipids, vitamins and other nutrients essential for normal growth, as well as relatively standard supply of caloric energy per gram of intake [10,15,16]. Limitations on growth or of increase in population, production in nature seem, to result largely from restrictions in the total food supply [17].
Food supply is probably the most potent factor affecting growth of fi sh. Proper feeding can make fi sh attain the maximum growth possible for the existing physico-chemical conditions. The effect of some factors such as temperature affects growth rates by initially effecting feeding and food requirements for fi sh. The art of preparing good feeds for fi sh is by formulating it based on the best attempts to duplicate the composition of natural foods. For example, growing of insects, harvesting small fi sh or other aquatic animals, or by processing culled domestic animals [18][19][20][21]. This is done to obtain high quality feed having lipids and other essential ingredients necessary for fi sh growth.
In fact, the best available food important in life of fi sh as a whole as observed in this experiment is diet type one. Fish fed on this diet responded much more instantaneous than others fed on other diets. The reasons for the variations as observed in this experiment may be due to differences in feed ingredients (i.e. lipids, carbohydrates, and proteins) and good balance between energy and growth. The good balance between energy and other materials for optimum anabolic activity, which in addition to growth includes tissues repair, reproduction and the formation of essential body products for example haemoglobin hormones and enzymes.
Dominique [22][23][24], reported that fats fed to fi sh at appropriate levels serves as the source of energy while sparing dietary proteins for other protein purposes in the body. This concept relates with the results obtained in this experiment where lipids were positively correlated with the mean fi nal increase in body weight of T. sparmanni caused by high intake of fats and ingestion of carbohydrate. In many fi sh species this would seem likely -oxidative of fatty acids that constitute a major energy source and essential fatty acids for structure and integrity of the phospholipid membrane [1,25]. However, fats should be supplied with care because the superimposing of supplemental fat in high protein diets results not only in large increase in body fat but, also restrict protein intake and, in some experiments, death of the fi sh [26]. Jauncey and Ross [27], recommends lipid levels of 10%, 8% and 6% in compounded tilapia diets for feeding 0.5 g, 0.5-3.5 g and above 3.5 g animals, respectively. Notes: FRC= Dry weight of food fed (g)/ wet weight gain in (g) Figure 1: Growth performance of T. sparmanni fed on different diet types. Although carbohydrates are the cheapest source of food energy, they are not all equally well utilized by all animals [28]. In this experiment diet type with increase in carbohydrate percentage did not result in subsequent increase in body weight. It means carbohydrate role was more on energy supply than increasing weight of the fi sh. The report by Phillips [29], indicated that levels of carbohydrate in diet under his experiment was limited to 12% digestible carbohydrate because any additional amount caused a disposition of excess liver glycogen, caused acute mortality. After his experiment Phillips [29], concluded that like in human being, fi sh were normally diabetic after feeding a sugar meal the blood glucose increased by 110%. This shows that fi sh were physiologically unable to utilize high levels of dietary carbohydrates due to its diffuse character of the pancreas in fi sh and its few insulin producing islets of Langerhans [30]. This fi nding may explain why signifi cant increase in body weight was not observed in fi sh fed with high carbohydrate contents in the diet. In this experiment approximately equal to the value of about 25% digestible carbohydrate suggested for tilapia by Jaunecy and Ross [27], was obtained as shown in Table 4.
Protein may serve as a source of energy for fi sh, but approximately 16% is nitrogen that cannot be used for life cycle [31]. Apparently both plant and animal proteins satisfy, at least in part, the protein requirement of most fi sh. Similar within a given species the food conversion effi ciency will differ from one food item to another.
In this case, the success of experimental diet has frequently been assessed in terms of the food conversion ratio [34][35][36][37][38][39]. Food conversion ratio (FCR) as shown in Table 3

Conclusion
The experiment has shown that type of feed given to a fi sh has an impact on his growth. Diet type one that had high amount of protein content promoted rapid growth of fi sh than diet type two that had high lipid and three with relatively high carbohydrate contents. On the other hand, food conversion ratio (FRC), an index that gives an approximate estimation of the best food and a key factor in comparing suitability of different feed types tended to be low in diet type one. These fi ndings show that diet type, one used in this experiment is highly recommended for feeding T. sparmanni compared to the other two feed types. results were reported by Jauncey and Ross [27], in which they found that 50%, 35% and 30% protein in the compounded diet was necessary for feeding 0.5 g, 0.5-35 g and above 35 g fi sh respectively. As shown in Table 3 diet type one had more protein content than the others. This result may explain why strong correlation was observed between increase in body weight and an increase in protein content in the diet. Diet type one has the highest performance in body growth rate while diet type three was the least in growth performance.
In most cases the effi ciency of food is normally measured by the amount necessary to produce a unit weight of fi sh i.e. food conversion ratio/food conversion effi ciency. The Feed Conversion Ratio, a major indicator of feed effi ciency in fi sh farming is fi gured by total weight of food given to fi sh to the total weight gained by the fi sh over a given period of time [32,33]. The higher the value of the food conversion ratio the less effi cient the feed is and vice versa. The food conversion ratio depends also upon the ability of individual fi sh to use food given to it. This ability differs according to species of fi sh, and