Growth,Feed Conversion,and Nutrient Retention Efficiency of African Catfish,Clarias gariepinus, (Burchell) Fingerling Fed Diets with Varying Levels of Protein

Growth, feed conversion, and nutrient retention efficiencies of African catfish fingerling, Clarias gariepinus (5.22 ± .07 cm; 8.22 ± 0.03 g), fed diets with varying levels of protein were assessed by feeding seven casein/gelatin based isocaloric (17.62 kJ/g GE) experimental diets with graded levels of dietary protein (20%, 25%, 30%, 35%, 40%, 45%, and 50% of the diet) to triplicate groups of fish to apparent satiation for eight weeks. Effects of feeding these diets on live weight gain (LWG%), feed conversion ratio (FCR), protein efficiency ratio (PER), protein retention efficiency (PRE%), and energy retention efficiency (ERE%) were assessed. Maximum LWG% (867%), PER (2.01), highest PRE (32%), ERE (69%), best FCR (1.39), and maximum body protein were recorded in fish fed diet containing 35% protein. On the basis of the second-degree polynomial regression analysis of the above response variables, it is recommended that the inclusion of protein in the range of 34.4%–39.6% is optimum for maximizing growth potential, feed conversion, and nutrient retention in African catfish fingerling, Clarias gariepinus.     

The growth and gonadal maturation of the African catfish, Clarias gariepinus (Burchell) broodstock fed differently heated soybean-based diets

An investigation was carried out to assess the growth and gonadal maturation of Clarias gariepinus (Burchell) fed differently heated soybean diets in concrete tanks. Four hundred and eighty male and female C. gariepinus (182 ± 10 g for females and 208 ± 5 g for males) were randomly distributed in groups into hapa nets. Iso‐nitrogenous (310 g kg^?1 crude protein) and iso‐caloric diets (355 Kcal kg^?1) prepared from raw soybean (D0) and soybean autoclaved for 5, 10, 15, 20, 25 and 30 min labelled D0, D5, D10, D15, D20, D25 and D30, were fed to the fish for 84 days. The fish meal based diet tagged DFM served as control. The male and female broodfish fed the fish‐meal‐based diet and diet D25 had significantly higher (P < 0.05) growth performance, gonad maturation, gonadosomatic index, relative fecundity and percentage egg fertilization and hatchability than the fish fed the other diets. The females had significantly higher (P < 0.05) weight increases and healthier condition over their male counterparts fed the same diets. This study showed that diet D25 was found to be the best substitute for fish meal that provided adequate nutrients required for the formation of genital products that produced strong offspring in C. gariepinus broodstock culture.     

Use of cassava as an energy source in a pelleted feed for the tilapia, Oreochromis niloticus L.

Abstract. An assessment of the nutritive value of cassava as an energy source in a pelleted lilapia diet was carried out. Four isonitrogeneous diets containing 15%. 30%, 45% and 60% cassava were formulated and fed to groups of Ortochromis niloucus L for 10 weeks. Good growth and food utilization efficiencies were obtained with all diets: there was a trend of improved growth and food utilization with increased cassava incorporation in the diet although there were no significant differences (P < 0–05) in food conversion ratio, protein efficiency ratio or apparent net protein utilization between the experimental diets. No nutritionally related pathology was observed in fish fed high cassava levels. Increased incorporation of cassava led to an increase in the carcass fat content although it was within the acceptable limits for tilapia. Phytoplankton growth occurred in all experimental tanks due to the fertilization effects of uneaten feeds and faeces as the water within the experimental lankiyuem was not exchanged: the contribution of phytoplankton to the nutrition of the experimental fish was not quantified but was considered to be minimal since the phytoplankton biomass was approximately an order of magnitude less than in fertilized systems.     

Nicotinic acid supplementation of diets for the African catfish, Clarias gariepinus (Burchell)

Semi-purified diets containing 39% crude protein and 5% lipid were used to identify the qualitative requirement of African cattish, Clarias gariepinus (Burchell), for niacin and to characterize the pathologies associated with a deficiency of this vitamin. After 48 days of feeding, C. gariepinus supplied with the unsupplemented diet had developed severe deficiency symptoms and were subsequently withdrawn from the growth study. Niacin deficiency was characterized by feed refusal, listlessness, weight loss, poor feed utilization and high mortality. The skin overlaying the lateral line of the deficient fish became haemorrhagic and this clinical sign was accompanied by severe anaemia. After 126 days of feeding, fish fed diets containing 17.0 mg niacin kg^?1 had also developed a dermopathy. but without anaemia or high mortality. The feeding of diets containing less than 33.1 mg niacin kg^?1 resulted in suboptimal feed efficiency and poor protein utilisation. Allometric analysis of proximate composition indicated that carcass moisture, protein and ash were influenced by fish size, and not by dietary niacin content. However, significantly more lipid per unit of weight gain was deposited in the carcasses of fish fed the unsupplemented diet than in fish fed diets containing 17.0mgkg^?1. The indicators used in the present study could not be applied to accurately determine a value for niacin requirement. However, until a more accurate assessment is performed, it is recommended that diets for C. gariepinus contain not less than 33.1 mg nicotinic acid kg^?1 feed.     

Nutritional evaluation of toasted Mucuna utilis seed meal and its utilization in the diet of Clarias gariepinus (Burchell, 1822)

The value of toasted Mucuna utilis seed meals was investigated in this study by evaluating the nutritional profile and the utilization of the processed seeds in isonitrogenous (35% CP) and isocaloric diets (17 kJ g?1) for African catfish Clarias gariepinus (Burchell 1822). Toasting the M. utilis seed significantly reduced the levels of tannins, phytate, trypsin, and hemagglutinin in the seeds. However, protein, gross energy, arginine, histidine, and valine were increased (P ≤ 0.05). The processed seed was then used to formulate five experimental diets by progressively increasing its inclusion (by 50 g kg?1) from zero up to 200 g kg?1. A sixth diet was also formulated with raw M. utilis included at 200 g kg?1 to determine the efficacy of the processing method applied in this study. Fifty fingerlings of C. gariepinus (2.02 g ± 0.08) stocked in 18 hapas measuring 1 × 1 × 1 m³ were then fed the diets for 56 days. The growth of C. gariepinus fingerlings was significantly improved by the addition of the toasted M. utilis seed meal. However, fish fed the diet containing 200 g kg?1 of raw M. utilis had poor growth with higher mortality (35%). Estimation of the feeding cost using the diets revealed reduction in production cost of fish with the inclusion of toasted M. utilis seed meal. It was concluded that toasting significantly improved the nutritional quality of this unconventional feedstuff, allowing better utilization at up to 200 g kg?1 inclusion level in the diet of African catfish C. gariepinus.     

Nutrient Assimilation by First‐Feeding African Catfish,Clarias gariepinus,Assessed Using Stable Isotope Analysis

Knowledge of ingredients assimilation and biomass contribution to recipient fish is important in feed formulation. The stable isotopes of ¹³C and ¹⁵N were used to investigate the assimilation and biomass contribution of bambaranut, Voandzeia subterranea, meal (BNM), corn, Zea mays, meal (CM) and fish meal (FM), in FM substituted diets of first feeding African catfish, Clarias gariepinus, during a 30‐d experiment. The catfish larvae were stocked at 40 fish/15 L three replicate glass aquaria. Larvae were fed with experimental diets varying FM, BNM, and CM. Proportions of FM : BNM : CM in the experimental diets were: feed 1 (F1) 60:20:20; feed 2 (F2) 40:40:20; feed 3 (F3) 20:60:20; and feed 4 (F4) 20:20:60. Feeds and larval stable isotopes of δ¹³C and δ¹⁵N were analyzed. Larval specific growth rates (SGRs) were high, enhancing incorporation of dietary δ¹³C and δ¹⁵N. The SGR was highest for catfish fed F1 and F2 but significantly lower for those on F3 and F4. Results of δ¹³C and δ¹⁵N analyses showed that the biomass contribution from FM was similar to BNM, which were better than CM at equal inclusion levels. The nitrogen contribution per ingredient to larval somatic crude protein was increasing with increases in ingredient inclusion and assimilation. Stable isotope analysis is useful for analyzing assimilation and utilization of nutrients.     

Soybean meal replacement by roquette (Eruca sativa Miller) seed meal as protein feedstuff in diets for African Catfish, Clarias gariepinus (Burchell 1822), fingerlings

Apparent digestibility coefficient (ADC) values for mechanically extracted meal derived from roquette (Eruca sativa) seeds were obtained. The digestibility of dry matter (DM), protein and energy was measured using an inert marker in the diets and by faeces collection using the dissection method. Soybean meal and roquette meal had similar ADC values for protein and energy. Roquette seed meal was thereafter evaluated as a protein source in diets (400‐g crude protein, 120‐g crude lipid and 18.00 MJ gross energy kg^?1 DM) fed to African catfish, Clarias gariepinus, fingerlings (10.4±0.4 g) to apparent satiation twice daily for 70 days. The test diets contained roquette seed meal as replacement for soybean meal protein in a control diet, providing 20%, 40% or 60% of the total protein. Catfish mortality was low (<10%) and not diet related. Substituting soybean meal protein with roquette seed meal protein providing 20% of total protein did not affect weight gain, growth response, feed conversion ratio, protein utilization or carcass composition of catfish. Catfish growth was, however, retarded and feed was poorly utilized only when roquette seed meal provided above 20% of total protein, caused by reduced energy digestibility, deficiencies in some essential amino acids and presence of antinutritional factors. Livers of catfish fed high dietary levels of roquette seed meal showed severe histological abnormalities.     

Apparent Digestibility Coefficients and Amino Acid Availability of Cricket Meal,Gryllus bimaculatus,and Fishmeal in African Catfish,Clarias gariepinus,Diet

A study was conducted on African catfish, Clarias gariepinus, to examine the apparent digestibility coefficient (ADC) of protein, dry matter, lipid, and energy, and the apparent availability coefficient (AAC) of essential amino acid (EAA) for a cricket meal (CM) diet, Gryllus bimaculatus, and fishmeal (FM). Both diets consisted of 30% isonitrogenous levels with a 70:30 ratio of basal diet to test ingredient. Chromic oxide (0.5%) was added to the diet as an inert marker. The ADCs of crude protein (CP) in CM (81.21%), lipid (89.82%), gross energy (64.42%), and dry matter (73.97%) was significantly higher (P < 0.05) than the value of CP (78.22%), lipid (82.03%), gross energy (56.52%), and dry matter (62.26%) in FM. All EAAs were present in both diets. The AACs for both diets ranged from 0.906 to 0.961 and 0.812 to 0.938 for the CM and FM diets, respectively. The growth performance of fish fed with CM exhibited significantly higher (P < 0.05) weight gain, feed conversion ratio, and protein efficiency ratio compared with FM. Overall, the results suggest that CM could be included in the African catfish diet without affecting their nutrient and amino acid digestibility as well as growth performance.     

Potential of local agricultural by-products for the rearing of African catfish Clarias gariepinus in Rwanda: effects on growth, feed utilization and body composition

This study was performed to evaluate the effect of replacing fish meal with local by‐products on Clarias gariepinus growth performance, feed utilization and body composition. A control diet contained 50% of fish meal. In four other diets, fish meal was partially replaced by vegetable and animal protein blend composed of sunflower oil cake, soybean oil cake, groundnut oil cake, bean meal, chicken viscera and blood meal. The study was conducted in a recirculating water system at a mean temperature of 23.6°C. The five test diets were compared with a commercial diet developed for African catfish. All diets were balanced to be equal in gross energy (19 kJ g⁻¹) and crude protein (40%). The experimental groups were fed in triplicate for 8 weeks, increasing fish weight from about 6.2 g at start to 52.3 g in the end. Best specific growth rate (SGR=3.4), feed efficiency (FE=1.3) and protein efficiency ratio (PER=3) were obtained with the control diet (diet 50% fish meal), although there were no significant differences between the group of fish fed the control diet and those fed diets based on groundnut oil cake or bean meal, whereas SGR (2.17), FE (0.85) and PER (1.95) were significantly (P<0.01) lower in fish fed diet containing sunflower oil cake. No significant differences (P<0.05) were found in fish fed commercial diet and diets containing bean meal or groundnut oil cake. Groundnut oil cake or bean meal can thus replace at least 50% of fish meal in the diet of Clarias fingerlings without amino acid supplementation. Because of its economic importance and its potential in animal nutrition sunflower oil cake is still an interesting feed ingredient, but its efficiency should be improved by various processing techniques. African catfish can utilize efficiently a diet with low percentage of animal protein without growth reduction.     

Effects of dietary Lactobicillus plantarum on the growth,carcass quality,and immune response of African catfish (Clarias gariepinus) challenged with Salmonella typhi

An experiment was conducted to investigate the effects of Lactobacillus plantarum on the production of African catfish (Clarias gariepinus). Five experimental diets containing 0, 10³, 10⁵, 10⁷, and 10⁹ CFU of Lactobacillus plantarum g^?1 diet (T₁–T₅ treatments respectively) were fed to African catfish (Clarias gariepinus) (9.20 ± 0.1 g initial body mass), for 70 days. Results indicated significantly lower growth performance in the fish fed diet without probiotics and in those fed diet with the least probiotic level. Treatments with probiotics significantly improved the blood profile and carcass protein but significantly reduced the carcass fat (P < 0.05); these treatments also marginally improved the carcass minerals in comparison with the treatment without probiotic (P < 0.05). Challenging the fish fed the experimental diets with Salmonella typhi showed higher immunity of fish fed the probiotic diets than those fed the nonprobiotic diet. Duncan’s multiple range test showed that the best fish performance was observed with 10³ CFU g^?1 L. plantarum for very parameter measured. However, regression analyses showed the optimum level of the bacteria to be 10^4.13–10⁵ CFU g^?1     

Temperature and dietary factors affecting the nitrogen efflux rates of the African catfish, Clarias gariepinus (Burchell)

Total ammonia and total nitrogen efflux rates of the African catfish, Clarias gariepinus (Burchell), were measured under different temperature conditions (20, 25 and 30^°C) and feeding regimes (50% protein, 40% protein and non-fed for 10 days). Both ammonia and nitrogen efflux rates were directly related to temperature. At all experimental temperatures, the 50%-protein-fed groups excreted higher levels of ammonia nitrogen than both the 40% protein and non-fed groups. No correlation of relative ammonia efflux (% ammonia/nitrogen) with either temperature or diet was observed under these experimental conditions. Such alterations caused by temperature and diet may have significant implications for an aquaculture system as low levels of dissolved ammonia are synonymous with optimum water quality.     

Effect of totally or partially replacing fish meal by alternative protein sources on growth of African catfish Clarias gariepinus (Burchell, 1822) reared in concrete tanks

A 12‐week feeding trial was carried out in concrete tanks to examine complete and partial replacement (75%) of fish meal (FM) with poultry by‐product meal (PBM), meat and bone meal (MBM) and soybean meal (SBM) in practical feeds for African catfish Clarias gariepinus. Triplicate groups of fish (initial body weight ranged from 90.33 to 93.93 g fish⁻¹) were fed seven isonitrogenous and isocaloric diets of 20% digestible protein and 300 kcal 100 g⁻¹ of digestible energy. The control contained 25% herring meal, whereas in the other six diets, PBM, MBM and SBM replaced 75% or 100% of the FM. Final body weight (FBW) and specific growth rate (SGR) of the fish fed diets containing PBM (75% and 100%), SBM (75% and 100%) and MBM (75%) were all higher, but not significantly different than those for fish fed the control diet. Replacing 100% of the FM by MBM significantly lowered FBW and SGR. Concerning whole body composition, there were no significant differences in ash and gross energy content of whole‐body among fish; fish fed diets containing PBM‐100% recorded significantly lower protein content compared with the control diet, while fish fed diet SBM‐100% recorded significantly lower moisture content compared with the control diet. Also fish fed diets SBM‐100% and PBM‐75% recorded higher lipid and gross energy contents compared with the control diet. The study revealed that satisfactory growth and feed utilization responses could be achieved through the replacement of FM by PBM, SBM and MBM in the diet of African catfish.     

Fish meal replacement by Cirina butyrospermi caterpillar's meal in practical diets for Clarias gariepinus fingerlings

Fifty‐six days feeding trial was conducted to evaluate the effect of Cirina butyrospermi caterpillar meal (CBM) as protein source in replacement of fish meal (FM) for Clarias gariepinus fingerlings. Six hundred African catfish (initial mean weight = 2.42 ± 0.01 g) were fed with four approximate isonitrogenous (48.97% crude protein), isolipidic (15.85% crude lipid) and isocaloric (21.10 kJg^?1) formulated diets, in which CBM progressively replaced FM at 0 (D1), 50 (D2), 75 (D3), 100% (D4) levels. At the end of the trial period, the best growth performance and nutritional utilization were observed in the group of fish fed with D2 and was not significantly different from those fed with D1 (the control diet). The survival rates, which ranged from 85.33% to 90.33%, were not significantly different among fish from the four diet treatments. The proximate whole‐body composition of C. gariepinus fingerlings fed the different diets showed similar moisture and protein contents. However, in contrary to ash which decreased, whole‐body lipid increased significantly when fish fed with diet containing CBM inclusion superior or equal to 75% (D3 and D4). The higher gross profit was obtained with D2 (16.73$), while the lowest was observed with D4 (10.16$). This study demonstrates that 50% of fish meal can successfully be replaced with CBM in C. gariepinus fingerlings diet without a negative impact on growth or feed utilization. This will yield a cheaper feeding for profitable production of African catfish fingerlings.     

A dynamic simulation model for growth of the African catfish,Clarias gariepinus (Burchell 1822): III. The effect of body composition on growth and feed intake

A feeding experiment was conducted in aquaria to study the effect of body composition on growth and feed intake of Clarias gariepinus. Fishes weighing about 20 g were fed diets with different protein to fat ratios. Diet A contained 60% protein, 7% fat and 19% carbohydrate. The composition of diet B was 20% protein, 7% fat and 54% carbohydrate. After 4 weeks the mean fish weight per tank amounted 33.2±1.5 and 27.5±1.4 g for fish fed diets A and B, respectively, while the fat content of the fish was 3.6±0.3 and 6.1±0.4%.During two consecutive periods of 21 days both the lean and the fat fish were fed diet A or B at five feeding levels. The feeding levels ranged from maintenance to above satiation. Fresh weight gain, protein gain and fat gain were higher with increasing feed ration, until a maximum was reached where extra feed did not result in more gain. This maximum gain was higher for diet A. Feeding with this high-protein diet resulted in better feed conversions compared with diet B. Within one diet, lean fish had a higher maximum growth rate compared to fat fish due to a higher feed consumption. Below the maximum gain, fat fish showed a slightly better conversion efficiency when fed with diet A.A explanatory model, for simulating growth of C. gariepinus, was extended in accordance with these experimental findings. It is assumed that the maximum consumption is regulated by both lipostatic and glucostatic mechanisms. The relevant parameter values were fitted with results obtained in the second experimental period. The adjusted model was tested by comparing simulation with experimental results found in the third period. The model gives good results for feeding levels providing sub-maximum gain. At the highest feeding levels of diet A, fed to initially fat fish, the model overestimated gain. The model was used to predict fresh weight gain of C. gariepinus fed diets with different compositions.     

A dynamic simulation model for growth of the African catfish,Clarias gariepinus (Burchell 1822): IV. The effect of feed formulation on growth and feed utilization

A dynamic simulation model is used to calculate growth of Clarias gariepinus (Burchell) fed with differently formulated diets. To verify the calculations, the results of the simulation are compared with experimental data. The experiments were carried out to determine the growth performance of C. gariepinus, fed with diets containing different protein sources. A fish meal diet was fed at four feeding levels in a respiration experiment. The alternative sources (blood meal, casein, groundnut, cottonseed, rapeseed and soybean) were tested at various inclusion rates with fish meal in aquarium experiments at one feeding level. Both experiments lasted two periods of 4 weeks each.The output of the simulation model, being fresh weight gain, protein gain, fat gain, oxygen consumption and ammonia production, agreed well with results from the respiration experiment, except for fat gain at the highest feeding levels and ammonia production in the second experimental period. It was shown that C. gariepinus is able to convert feed nutrients very efficiently into fish biomass. A protein conversion efficiency of nearly 60% was found.In the aquarium experiments the fresh weight gain decreased when an increasing part of the fish meal was replaced by alternative protein sources. The output of the simulation model (fresh weight gain) in comparison with the experimental results showed that it is possible to calculate the weight conversions of differently formulated diets, when there is a reliable estimation of the amino acid composition of the protein sources used.     

Complete replacement of fish meal by other animal protein sources on growth performance of <Emphasis Type="Italic">Clarias gariepinus</Emphasis> fingerlings

To completely replace the fish meal by a mixture of earthworm and maggot meals, experimental diets were tested during 42 days on Clarias gariepinus fingerlings. Five isoproteic and isoenergetic diets (40 % crude protein and 17.9 ± 0.3 kJ g^?1) including the control diet (D1) based on fish meal, were formulated. All these diets satisfied the essential amino acids requirements of C. gariepinus fingerlings. These diets were tested on triplicate groups of 50 fishes (initial body weight: 3 ± 0.1 g) bred in tank (0.5 m³). The approximate ratios 2:5; 1:4; 1:12 and 0:1 between the earthworm meal and the maggot meal were used, respectively, to formulate four diets D2, D3, D4 and D5 without fish meal. After the feeding period, significant differences (P < 0.05) were observed on growth, feed utilization between control diet (D1) and test diets (D2–D5). Fish fed earthworm- and maggot-based diets were grown better than those fed the control diet. Survival and feed utilization were not significantly affected by the ratio between earthworm meal and maggot meal in the test diets. Lipid content was higher in carcass and fillet of fishes fed earthworm- and maggot meals-based diets than that of those fed fish meal-based diet. This study indicates that when the ratio 2:5 between the earthworm meal and the maggot meal is used to entirely replace fish meal and the ratio lysine/arginine of the diet is inferior to 1, the growth performances and feed utilization of Clarias gariepinus fingerlings are improved.     

Evaluation of Chuni, a commercially available low-cost cattle fodder, in the diet for rohu, Labeo rohita (Hamilton), fingerlings

An 80-day feeding experiment was conducted to evaluate the suitability of incorporation of Chuni, a commercially available low-cost cattle fodder, comprising cereal grains and leguminous seeds, into the practical diets for rohu, Labeo rohita (Hamilton), an Indian major carp, fingerlings (average weight= 6.23 0.15g). Four experimental diets, incorporating Chuni at levels of 10%, 20%, 30% and 40% into a fish-meal-based control diet (35% protein) were formulated. In terms of fish growth, feed conversion, protein efficiency ratio, apparent nutrient digestibility, and protein and lipid deposition in fish muscle, 10%Chuni incorporated diet showed the best performance of fish and was comparable to those with the control diet. However, the growth of fish was lower with higher levels of Chuni incorporation (20% or more), which resulted in poor nutrient digestibility. The present results indicate that Chuni could be used as a component in the supplementary diet for L. rohita fingerlings, partially substituting the fish-meal-based diet up to the extent of 10%, and it this is the first report on the use of Chuni as a dietary ingredient in diets for carp.     

Approaches to optimizing dietary protein to energy ratio for African catfish Clarias gariepinus (Burchell, 1822)

An 8‐week feeding trial was conducted in a recycling water system at 28 ± 1 °C to investigate protein to energy ratio (P/E ratio) in African catfish Clarias gariepinus (10.9 ± 0.04 g). Six fishmeal‐based diets of two protein levels (330 and 430 g kg^?1), each with three lipid levels (40, 80 and 120 g kg^?1) resulted in P/E ratios ranging from 15.5 to 21.3 mg protein kJ^?1 gross energy (GE) were fed to 20 fish (per 30‐L tank) in triplicate. Fish were fed 50 g kg^?1 of their body weight per day adjusted fortnightly. Significantly higher (P < 0.05) growth rates and feed conversion efficiency were evident in fish fed with higher protein diet. The highest growth rate was found by fish fed 430 g kg^?1 protein, 21.2 kJ^?1 GE with a P/E ratio of 20.5 mg protein kJ^?1 GE. Significantly indifferent (P > 0.05) values of protein utilization were found in‐between the both (higher and lower) protein diets. Higher lipid deposition (P < 0.05) in whole body and liver was observed with increasing dietary lipid level at each protein diet and as higher (P < 0.05) for the lower protein diets. Liver glycogen tended to decrease with increasing gross energy at each protein diet and higher protein diet showed comparatively lower values (P > 0.05). Digestive enzyme activities (protease and lipase) and histological examination of intestine and liver of fish fed varying P/E diets found no significant differences in response to experimental diets. The study reveals that African catfish C. gariepinus performed best the diet containing 430 g kg^?1, 21.2 kJ g^?1 and 20.5 mg protein kJ g^?1 GE protein, gross energy and P/E ratio, respectively.     

Performance of Hybrid Clariid Catfish Fingerlings (Clarias gariepinus ♂ × Heterobranchus bidorsalis ♀) Fed Poultry Layer Waste Diets in Aquaria

Abstract

The performance of poultry layer waste (PLW) meal as a dietry protein inclusion for hybrid clariid catfish (Clarias gariepinus♂ ×Heterobranchus bidorsalis♀) fingerlings (hetero-clarias), cultivated in glass tanks, was evaluated. Four isonitrogenous diets (35% crude protein) were fed to unsexed hetero-clarias fingerlings for 90 days. The inclusion levels of the PLW meal were at 0%, 10%, 20% and 30%. Growth performance and nutrient utilization of the fish were based on percentage daily weight gains, specific growth rate, feed conversion ratio and protein efficiency ratio. There were no significant differences (P> 0.05) in growth performance and nutrient utilization of the fishes fed on diets containing up to 30% PLW inclusion. All fish fed diets containing PLW did better (P> 0.05) than those fed the control diet. The most cost-effective diet in terms of cost-weight gain was diet containing 10% PLW. These results indicate that up to 30% of PLW meal could be included in the diet of hybrid diet catfish.