ABSTRACT
The present work was carried out to study the effect of partial replacement of yellow corn by dried citrus pulp (as unconventional feed stuff) with and without addition of Bio-Buds (as a probiotic) in the diets of Nile tilapia fingerlings and its effect on growth performance, nutrient digestibility, and immune status. A total of 360 Nile tilapia fingerlings with an average body weight of 17±3gm were used. The fish were randomly divided into 6 equal triplicate groups (each replicate contained 20 fish) and distributed in cages placed in artificial concrete ponds with a good source of water supply. A basal control diet was formulated to fulfil the nutrients requirement of fish according to NRC and contained 30.80% CP and 2940 kcal/kg DE. In the experimental diets yellow corn was partially replaced by dried citrus pulp at rate of 5 and 10% with and without addition of Bio-Buds at rate of 0.2%.The fish were fed isonitrogenous, isocaloric diets 3 times daily at rate of 3% of body weight for 12weeks. Results revealed that the dietary treatments had a highly significant effect (P<0.05) on growth performance parameters. The fish fed diet contained 5% dried citrus pulp with Bio-buds had a significant higher final body weight, body gain, and body gain % as compared to fish fed other dietary treatments. Moreover, fish fed diet contained 5% dried citrus pulp with Bio-buds had consumed a significant higher amount of feed as compared to those fed the control diet with and without bio-buds. Fish fed diet contained 5% dried citrus pulp with Bio-buds had utilized their feed more efficiently (lower values of FCR) than those fed the control diet without bio-buds or diet contained 5and 10% dried citrus pulp without bio-buds. Significant higher values of protein utilization parameters were recorded for fish fed diet contained 5% dried citrus pulp with Bio-buds as compared to that for fish fed the control diet without bio-bud or diets contained 5 and 10% dried citrus pulp without bio-buds. Numerical higher values of dry matter, crude protein, fat and crude fiber digestion coefficient were recorded for fish fed the control diet with bio-buds and diets contained 5 and 10% dried citrus pulp with bio-buds. Some immunological parameters were significantly improved due to supplementation of the diets with bio-buds. It could be concluded that dried citrus pulp could replace up to 10% of yellow corn in Nile tilapia fingerling diets with addition of bio-buds without any adverse effects on growth parameters, nutrient digestibility or immune status.
INTRODUCTION
Nutrition plays an important role in intensive fish production depending upon the type of feed availability and its cost. Feeding cost exceeds 50% of operation costs (1). In Egypt, a considerable attention has been paid to use non-conventional feed stuffs either from protein or energy sources, instead of fish meal and yellow corn which constitute the largest part balanced diets. On the other hand, yellow corn became very expensive since it represents the main energy source in livestock feeding and there are high competition on it between farm animals,i.e., poultry and fish. For these reasons nutritionists try to replace part of the yellow corn as the main source of energy by another non-conventional energy sources such as peels of citrus fruits and sugar beet pulp providing the optimum energy level in diets for fish is important.It has been recorded that rather than discarding the orange peels, it can be sun-dried and then milled in grinding machine to fine particle to obtain the orange peel meal which can be included in fish diets (2). Up to 15% dietary maize in broiler diet can be replaced with sun dried sweet orange rind without reducing the growth performance of broilers, therefore the inclusion of sun dried sweet orange rind as a replacement of high cost maize in the broiler diet, reduce the high cost of the diet (3). Sweet orange (Citrus sinensis) peel meal obtained from ground sun dried peels can replace dietary maize in broiler chicken diet at 20% level without any adverse effect on performance (4).Addition of2 gm /kg diet super bio-buds (Saccharomyces cerevisiae) can improve body gain, feed utilization, survival rate and enhance resistance to challenge infectionin Nile tilapia fish(5).Nile tilapia fish received Probiotics (Saccharomyces cerevisiae) supplemented diets revealed significant improvement in growth parameters (body Weight gain, feed conversion ratio, and protein efficiency ratio) (6).
The present study was aimed to evaluate the effect of replacement of yellow corn by dried citrus pulp as unconventional feed stuff with and without addition of Bio-Buds as a probiotic in the diets of Nile tilapia fingerlings and its effect on growth performance, nutrient digestibility, and immune status.
MATERIALS AND METHODS
Experimental fish used:- A total of 360 Nile tilapia Fish (Oreochromis niloticus) were procured from private fish farm, Abbassa village, Abu-Hammad district, Sharkia Governorate, Egypt. The fish were nearly of the same size, apparently health and had an average weight of 17±3 gm. The fish were divided into equal 6 triplicate groups (each replicate contained 20 fish) and kept in the cages in the artificial concrete pond for two weeks to be acclimatized before the start of the experiment. The fish were located in artificial concrete ponds, each replicate of the groups were stocked in a cage made from plastic meshed material, with 80cm x 80cm x 80cm dimensions. The cages were located above the bottom of the pond. The pond had 3 net partitions which divided it into 4 equal parts. They were supplied with dechlorinated water and air supplied by a large air compressor. Water temperature, dissolved oxygen, PH, ammonium (NH4), nitrite(NO2) and nitrate (NO3) were measured three times during the experiment and found to be 28-320C±20C, 5.2mg/L, 7.5, 0.4 mg/L, 0.15 mg/L, 10 mg /L Respectively.
The feed additives used:-Super Bio-Buds (Natural growth promoter):- used as a probiotic, each 1gm contains live cell yeast
(Saccharomyces Cerevisiae), 800 million CFU/gm. Produced and exported by Brook Side Agra. USA, imported by Top Vet international Egypt.
Diets and feeding:-Six isonitrogenous, isocaloric diet were formulated
(7) containing 5% and 10% dried citrus pulp with and without addition of Bio-Buds (2gm/kg) diet for 12 weeks. Proximate chemical composition of feedstuffs used in formulation of the experimental diets is shown in Table 1 and the formulations and composition of the experimental diets are shown in Table 2. All fish groups were fed on the diets at the rate of 3% from body weight during the experiment.
Growth performance parameters
The fish of each group were weighed at the beginning of the experiment to obtain initial body weight, then weighed every 3 weeks intervals (8,9).Weight gain was calculated as the final average body weight - the initial average body weight. Weight gain percentwas calculated by the following formula (final average body weight - initial average body weight) / (initial average body weight) x 100 (10). Specific growth rate %was calculated (11). Feed conversion ratio (FCR) was calculated as (dry feed intake by gm) / (live weight gain by gm)(9). Protein efficiency ratio (PER) was calculated as (live weight gain by gm) / (protein intake by gm) (12). Protein retention was calculated as (final av. B.W.) X (D.M. content of final fish) x (protein content of final fish) - (initial av. B.W.) X (D.M. content of initial fish) x (protein content of initial fish) /100 (11). Protein productive value (PPV) was calculated as (protein retention) / (protein intake by gm) x 100(11). Condition factor (K) was calculated as (body weight by gm) / (total length cm)3 x 100 (13).
Immune status
Total leukocytic count (TLC) and differential leukocytic countwere determined (14,15). Phagocytic % was determined as Number of Neutrophils containing Candidia albicans / Total number of counted Neutrophils. Phagocytic index was determined as total number of C. albicans in 100 Neutrophils / 100
Apparent digestibility of the diets
For determination of the apparent digestibility of the diets, chromic oxide was used as a digestibility indicator(16). The finally ground ingredients of each diet were weighed according its formulation and chromic oxide powder was added at a rate of 5 gm per kilogram of diet (0.5 %). Each diet was thoroughly mixed and pelleted to 1.5 mm diameter.Large individuals of each fish group at the end of experiments were reared in glass aquaria (30 x 40 x 150 cm) which contained aerated water at a water temperature 26 - 29 °c (9 fishes / aquarium) and given diets containing chromic oxide two times daily for one week as adaptation period, then for two weeks as a collection period.Chromic oxide content in faeces and in experimental diets was determined (17)in the base of organic substance in the experimental materials were ashed using oxidation reagent(18). Dry matterdigestibility was calculated (% indicator in faeces) - (% indicator infeed) / (% indicator in faeces) x 100 (7). Nutrients digestibility was calculated as = 100 - {100 ( % indicator in feed ) / ( % indicator in faeces ) X ( % nutrient in faeces ) / (% nutrient in feed ) (7).
Statistical analysis
The obtained data in this study were statistically analyzed for variance ANOVA, LSD (Least significant difference) (19).Differences among treatment means were compared using Duncan's multiple range test (20). Data were presented as mean ± SE and significance was declared at (P < 0.05).
RESULTS AND DISCUSSION
Growth performance parameters
The effect of dietary treatments on growth performance of Nile tilapia fingerlings is present in Table 3. Fish group fed the control diet with Bio-buds and the diet contained 5% dried citrus pulp with Bio-buds had recorded a significant (P <0.05) higher final average body weight (32.19 and 32.99 g, respectively) as compared to fish fed the other dietary treatments. Moreover, fish group fed on diet contained 10% dried citrus pulp with and without Bio-buds had recorded a significant (P<0.05) final average body weight (31.07 and 30.94 g, respectively) as compared to those fed the control diet without Bio-buds (29.95 g).
Concerning the body gain and body gain percent followed a similar trend; the fish group fed on diet contained 5% dried citrus pulp with Bio-buds or the control diet with bio-buds had a significant higher values as compared to those fed the control diet without bio-buds or the diet contained 5 % dried citrus pulp without bio-buds. Nile Tilapia fish received probiotic (Saccharomyces cerevisiae) supplemented diets revealed a significant increase in growth performance parameters (6). Sweet orange peel meal obtained from ground sun dried peels can replace high cost corn in the broiler chicken at 20% without any adverse effect on growth performance and this leads to decrease the cost of diet (21).
The feed intake was significantly (P<0.05) affected due to dietary treatments where fish groups fed on diets contained 5% dried citrus pulp with and without Bio-buds and diet contained 10% dried citrus pulp without Bio-buds had consumed a significant higher amount of feed as compared to fish fed the control diet with bio-buds or the diet contained 10% dried citrus pulp with bio-buds. Feed conversion ratio (FCR)
data revealed that fish fed the control diet with bio-buds or the diet contained 5%dried citrus pulp with bio-buds had utilized their feed more efficiently than fish fed the control diet without bio-buds or diet contained 5% and 10% dried citrus pulp without bio-buds. Addition of super bio-buds to Nile tilapia fish diets have improved feed utilization
(5,6). On contrary incorporation of low (5%) or moderate (10%) percentages of citrus pulp in broiler chickens diets increased the levels of dietary soluble NSP and led to impaired growth rates and FCR
(22).
Protein utilization
The protein efficiency ration (PER), protein retention and productive value (PPV) at the end of the study are showed in Table 3. There were significant differences between different fish groups, where the fish group fed on diet contained 5% dried citrus pulp with Bio-buds and fish fed the control diet with Bio-buds had a significant higher values as compared to fish group fed on diet contained 10% dried citrus pulp with Bio-buds, fish group fed on diet contained 5% dried citrus pulp without Bio-buds, fish group fed on diet contained 10% dried citrus pulp without Bio-buds and control group without Bio-buds.
From these data, it is clear that Bio-buds improved the protein utilization in Nile Tilapia fish and dried citrus pulp can be replaced up to 10% with Bio-buds without any adverse effect on Nile Tilapia fish.
The utilization of sweet orange peels improved the protein utilization in broilers chicken (23-25). Also, it has been found that Seaban juvenile diets supplemented with Saccharomyces cerevisiae improved protein utilization (26).Also, protein utilization was improved when super bio-buds were added to Nile tilapia fish diets(5,6). Supplement of yeast based diets with deficient amino acids had beneficial effects on fish growth performance and protein utilization (27).
Condition factor (K)
The results of condition factor (k) at the end of the experiment are present in Table 3. There were significant differences between fish groups. The highest values were recorded in fish group fed on diet contained 5% dried citrus pulp with Bio-buds (1.96) and control group with Bio-buds (1.91) in comparison with other groups. These results were supported by previously study which reported that the high condition factor is an indicator to the good nutritional (healthy) state of fish (14).
Immunological parameters
Table 4 shows the effect of experimental diets on some immunological parameters in different fish groups. There were significant differences (P <0.05) between fish groups. The fish groups fed on diet contained 5% dried citrus pulp with Bio-buds, 10% dried citrus pulp with Bio-buds and control group with Bio-buds had a significant higher values of Total leukocytic count (TLC), differential leukocytic count and phagocytic activity (phagocytic% and phagocytic index) as compared with other dietary treatments. Some yeast like Candida sp. and Saccharomyces cerevisiae have immunostimulatory properties by virtue of their complex carbohydrate components of nucleic acid content (28). Addition of 2 gm/kg diet super Bio-buds (Saccharomyces cerevisiae) can enhance resistance (improved immune status) to challenge infection in Nile Tilapia fish (5). Nile Tilapia fish received probiotics (Saccharomyces cerevisiae) supplemented diets revealed significant (P <0.05) improvement in growth parameters and immunological parameters (6).
Digestibility of the diets
The effect of partial replacement of yellow corn by dried citrus pulp with and without addition of Bio-buds in the diets of Nile Tilapia fish and its effect on digestibility of dry matter, crude protein, fat and crude fiber are present in Table 5. These results showed that the highest digestibility coefficient values of DM, CP, Fat and CF were recorded in fish groups fed on diet contained 5% dried citrus pulp with Bio-buds followed by control group with Bio-buds, while the lowest digestibility coefficient of DM, CP, fat and CF were observed in control group without Bio-buds, followed by fish group fed on diet contained 5% dried citrus pulp without Bio-buds then fish group fed on diet contained 10% dried citrus pulp without Bio-buds and fish group fed on diet contained 10% dried citrus pulp with Bio-buds. In Nile Tilapia fish it has been investigated that dried Yeast (
Saccharomyces cerevisiae) improved nutrient utilization and digestibility of nutrients
(5,6,29)
REFERENCES
1.Scharoder G L (1977):Agriculture waste in fish farming. A commercial Application of the culture of single cell organisms for protein production. Water Res.,1:419.
2.Ipinjolu J K (2000): Performance of juvenile orange koi carp (Cyprinucarpio leanneanus) fed diets supplemented with sweet orange peel meal: Body composition, nutrition, utilization and skin pigmentation. Sokoto Journal of Veterinary Science 2000: 228-229.
3.Oluremi O I A , Ojighen V O and Ejembi E H (2006): The Nutritive potentials of Sweet Orange (Citrus sinensis) rind in broiler production. International Journal of Poultry Science 5: (7):613-617.
4.Agu, P N , (2006): Nutritional Evaluation of Sweet orange (Citrus sinensis) peel as a feed resource for Broiler chickens unpublished M.Sc. Thesis Department of Animal Production, University of Agriculture, Makurdi, Nigeria.
5.Ahmed M M E , Mohamed F M and Salah M A (2008):effect of biobuds as a commercial probiotic product in cultured tilapia, 8th International Symposium on Tilapia in Aquaculture 2008, The WorldFish Center, Regional Research & training Center for africa & west Asia, Abbassa, Egypt.
6.Marzouk M S , moustafa M M and Nermeen, M Mohamed, (2008): the influence of some probiotics on the growth performance and intestinal microbial flora of o. niloticus, 8th International Symposium on Tilapia in Aquaculture 2008, 1059-1071.
7.NRC (National Research Council). (1993):Nutrient Requirements of fish. National Academy Press, Washington, DC, 112pp.
8.Windell, J.T., Foltz, J.W. and Sarokon, J.A. (1978): Methods of faecal collection and nutrient leaching in digestibility studies. Prog. Fish cult. 40: 51-55.
9.Siddiqui A Q , Howlader M S and Adam A A (1988): Effects of dietary protein levels on growth, feed conversion and protein utilization in fry and young Nile Tilapia (Oreochromus niloticus). Aquaculture 70: 63-73.
10.Jauncey K and Ross B (1982): A guide to Tilapia feeds and feeding. University of Stirling, institute of Aqua culture, Stirling, Scotland.
11.Castle J D and Tiews K (1980): Standardization of methodology in fish nutrition research. Report of EIFAC, IUNS and ICES working group on EIFAC (technical paper Nr. 36, EIFACT 36.
12.Stuart J S and Hung S S O (1989): Growth of Juvenile white sturgeon (Aciponser transmention) fed different proteins. Aquaculture, 76, 303-316.
13.Gjedrem, T and Gunnes, K ( 1978 ): Comparison of growth rate in Atlantic salmon, Pink salmon, Artic char, Sea trout and Rainbow trout under Norwegian farming condition, Aqua., 13: 135- 141.
14.Stoskoph M (1993): Fish Medicine. W.B. Saunders Company, PP,116,128,129.
15.Schalm O W (1986): Veterinary Hematology. 4th Ed., Lea and Febiger, Philadelphia.
16.Cho C Y and Singer S J (1978): significance of digestibility measurement information of feeds for rainbow trout EIFAC 78 SMMP E60. Cited after EL-Eraky (1985), M.D. Thesis modellversuche Zur Futter wertabschatzung verschiedeener protein-quellen in Der Futterung von Forellen (S. Gairdnneri Rich).
17.Petry H and Rapp W (1971): Zur problematik der chromoxidbest immung in verdauungs versuchen. Zeitschrift fur tierphysiologie, tierernahrung und futter mittelkde. 27, (4): 181-189.
18.Bolin D W , King R P and Klostermann E W (1952): A simplified method for the determination of chromic oxide when used as an index substance. J.Sci. 116, 634.
19.Snedecor, G W and Cochran, W G (1982):Statistical methods. 8th Ed., Ames. Lowa state university.
20.Duncan D B (1995): Multiple range and multiple F-tests. Biometrics 11, 1-42.
21.Oluremi O I A, Wuanor G j and Orayaga K T (2009):Effect of Fermentation on Some Chemical Constituents in Sweet Orange (Citrus Sinensis) Peal Meal and Nutrient Digestibility in Broiler Chickens.Proceedings of 14th Annual Conference of Animal Science Association of Nigeria (ASAN)September 14th - 17th 2009, LAUTECH Ogbomoso, Nigeria.
22.Moura˜o J L , Pinheiro V M , M Prates J A , Bessa R J B , Ferreira L M A , Fontes C M G A and Ponte P I P , (2008): Effect of Dietary Dehydrated Pasture and Citrus Pulp on the Performance and Meat Quality of Broiler Chickens.Poultry Science 87:733-743.
23.LanzaM , Fasone V , Galofaro V , Barbagallo D , Bella M and Pennisi P (2004):Citrus pulp as an ingredient in ostrich diet: effects on meat quality. Meat Science 68. 269-275.
24.Jawale M R , Zanzad A A , Kukde R J and Kambale R S , (2005): Economics of Rearing Broilers on Orange Pomace Based Diets Supplemented with Enzymes. J. Bombay Vet. Coll 13 (1 & 2): 20-22.
25.Oluremi O I A , Mou P M and Adenkola A Y , (2008): Effect of fermentation of sweet orange (Citrus sinensis) fruit peel on its maize replacement value in broiler diet. Livestock Research for Rural Development 20 (2).
26.Oliva-Teles and Goncalves,P (2001): partial replacement of fish meal by brewers yest( Saccharomyces cervisae) in the diets for seabass juveniles. Aquaculture 202,269-278.
27.Murray A P and Marchant R (1986): Nitogen utilization in rainbow trout fingerlings (Salmo gaindneri Richardson). Fed Mixed microbial biomass. Aquaculture 54,263-275.
28.Andreson D P , Siwicki A K and Rumsey G L (1995): injection or immersion delivery of selected immunostimulant to Trout demonstrate enhancement of nonspecific defense mechanisms and protective immunity. In: sheriff, M., Arthur, J.R., Subasinghe,R.P.(Eds), Diseases in Asian Aquaculture:II Fish Health Section. Asian Fisheries Society, Manila,PP.413-426.
29.Khalil F F M (1999):Effect of varying dietary protein sources and levels on growth performance and feed utilization of tilapia Nilotica fish (Oreochromis Niloticus). Egypt.J.Nut. Feeds. 2: 99-109.
30.Santiago C B , Banes-Aldaba M And Laron M A (1982): Dietary crude protein requirement of Tilapia nilotica fry Kalikasan, philipp. J. Biol. 11(2-3): 255-265.