*Corresponding author: Chitra G ISSN: 0976-3031
Research Article
EFFICACY OF COMMERCIAL PROBIOTICS (EUBIOZ) ON GROWTH, BIOCHEMICAL
COMPOSITION AND NUTRITIONAL INDICES OF INDIAN MAJOR CARP,
CATLA CATLA
Premalatha Z
1and *Chitra G
21
Department of Zoology, Nirmala College for Women (Autonomous), Coimbatore – 641018
2Department of Zoology, Nirmala College for Women, Coimbatore – 641018
DOI: http://dx.doi.org/10.24327/ijrsr.2019.1011.4843
ARTICLE INFO ABSTRACT
The present study evaluated a commercial probiotic, Eubioz (mixture of several strains of bacteria and yeast) to determine its efficacy and the dose necessary to improve growth, biochemical composition and nutritional indices in Indian major carp, Catlacatla. Fishes of both sexes weighing 4 ± 0.5 gm were fed with a basal diet supplemented with 0 g kg−1 (Control), 1 g kg−1, 2 g kg−1 and 3 g kg−1 of the commercial probiotic Eubioz for 60 days. At the end of the feeding trial weight gain, length gain, specific growth rate and feed conversion ration were enhanced in all probiotic supplemented groups and maximum (P < 0.05) improvement in the 3 g kg−1 diet fed fishes. Feed conversion ratio (FCR), protein efficiency ratio (PER), protein productive value (PPV) and feed efficiency (FE) were significantly (P < 0.05) highest in the 3 g kg−1 diet fed fishes. Enhanced (P < 0.05) biochemical composition in the muscle tissues of all treated groups were observed. These results indicated that combined administration of bacteria and yeast can be considered as beneficial feed additive and growth promoter in C. catla.
INTRODUCTION
Semi-intensive and intensive fish farming is gaining importance in India. Artificial feed plays an important role in semi-intensive fish culture, where it is required to maintain a high density of fish than the natural fertility of the water can support. The role of supplementary feed in intensive fish farming cannot be ignored as the whole nutritional requirements of fish depend upon the feed (Ayyappan and Jena, 2008). For fish supplementary diet, the continuous dependence on conventional feed stuffs such as fish meal and fish oil has lead to an increase in the prices of these components. Although fishmeal represents an ideal nutritional source of dietary protein and lipid for fish, there is an urgent need to reduce the current total of the feed industry upon this expensive and finite commodity of uncertain supply and cost. Financial limitations are depressing the development of aquaculture because of the impact of the increasing prices of fish meal and other traditional protein feed stuffs. Hence research is needed to intensify and utilize less expensive and more sustainable ingredients in fish feeds, while maintaining nutritional quality equal to or better than those based mainly on fish meal.
In India, with the emergence of large scale commercial carp culture, diseases of varied aetiology are being increasingly recognized as major hurdle to successful and sustainable farming. Disease outbreaks are constraint to aquaculture production thereby affects both economic development of the country and socio-economic status of the local people. Disease control in aquaculture industry has been achieved by following different methods using traditional ways, synthetic chemicals and antibiotics. However, the use of such expensive chemotherapeutants for controlling diseases has been widely criticized for their negative impacts like accumulation of residues in tissues, environmental pollution, development of drug resistance in pathogens, immunosuppression and reduced consumer preference for aqua products. Traditional methods are also ineffective against controlling new diseases in large aquaculture systems. Therefore, alternative methods need to be developed to maintain a healthy environment in the aquaculture systems thereby to maintain the health of the cultured organisms (Sahu et al., 2008).
Use of probiotics is gaining importance in controlling potential pathogens and for the improvement of fish health and aquatic environment. Probiotics are quite common in health promoting "functional foods" now a day for humans, as well as
International Journal of
Recent Scientific
Research
International Journal of Recent Scientific Research
Vol. 10, Issue, 11(F), pp. 36126-36130, November, 2019
Copyright © Premalatha Z and Chitra G, 2019, this is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited.
DOI: 10.24327/IJRSR
CODEN: IJRSFP (USA)
Article History:
Received 4th August, 2019 Received in revised form 25th September, 2019
Accepted 23rd October, 2019
Published online 28th November, 2019
Key Words:
therapeutic, prophylactic and growth supplements in animal production and human health (Senok et al., 2005). Probiotic is a live microbial adjunct, which has a beneficial effect on the host by modifying the host associated or ambient microbial community, by ensuring improved use of the feed or enhancing its nutritional value, by enhancing the host response towards disease or by improving quality of its ambient environment. The beneficial effects of probiotics include higher growth and feed efficiency, immuno-stimulatory functions, prevention of intestinal disorders and pre-digestion of anti nutritional factors present in the ingredients (Watson, 2008).
EL-Haroun et al., (2007) conducted a feeding trial to evaluate the effect of dietary probiotic Biogen supplementation on growth performance and feed utilization efficiencies of Nile tilapia, Oreochromis niloticus (L.). Yu et al., (2007) conducted a feeding trial to study the effects of dietary Bacillus on the growth, digestive enzyme activity and serum biochemical parameters of the shrimp, Litopeneaus vannamei. Balcazar et al., (2008) evaluated the ability of three lactic acid bacteria isolated from fish Lactococcus lactis, Lactobacillus plantarum and L. fermentum to inhibit adhesion of several fish pathogens, Aeromonas hydrophila, A. salmonicida, Yersinia ruckeri and Vibrio anguillarum to host intestinal mucus under in vitro conditions. The effect of probiotic bacterium, Enterobacter faecium on growth performance and immune responses of tilapia, O.niloticus was analysed by Wang et al., (2008). Aly et al., (2008) reported the characterization of some bacteria (Bacillus pumilus, B.firmus and Citrobacter freundii) isolated from O.niloticus and their potential use as probiotics. The need, principles and mechanisms of action and screening processes of probiotics in aquaculture was reported by Watson et al., (2008). Son et al., (2009) studied the effect of dietary administration of probiotic L.planatarum enhanced the growth, innate immune responses and disease resistance in the grouper, Epinephelus coioides. The present study has been designed to study the influence of commercial probiotic, Eubioz (mixture of several strains of bacteria and yeast) on growth, biochemical composition and nutritional indices of Indian Major Carp, Catlacatla.
MATERIALS AND METHODS
Collection and maintenance of Catla catla
The Indian major carp, Catla catla (Family: Cyprinidae), is a fresh water edible fish has been selected for the present investigation. Normal and alive fingerlings were collected from Aliyar dam, near Pollachi at Coimbatore, Tamil Nadu, India. The collected fishes were transported to the laboratory in a polythene bag containing oxygenated water. The fish were kept in large aquarium tanks and acclimatized in the laboratory condition for one month in non-chlorinated water. Fishes of both sexes weighing 4 ± 0.5 gm were used. During acclimatization fishes were fed once a day with control feed prepared in the laboratory and water was changed on alternative days.
Preparation of experimental feeds
The commercially available probiotic strain, Eubioz was selected and tested for their efficacy in the experimental fishes. These commercial probiotics contain live cultures of Lactobacillus acidophilus, L.rhamnosus, Bibidobacterium
longum, B. bifidum, Streptococcus thermophilus and Saccharomyces boulardii. Probiotic tablets were collected from the local pharmaceutical store, ground well using mortar and pestle and made into a fine powder. The feed ingredients used in fish feed were rice bran, groundnut oil cake, powdered probiotics and tapioca flour (as a binder). All the ingredients except probiotics were mixed thoroughly in a mix blender. The required amount of water was added to mixed ingredients to form soft dough. Then the dough was kept in an airtight polyethylene packet for one hour for proper conditioning followed by steam cooking for 20 minutes. Powdered probiotics were added to the feed after cooling, mixed well and passed through an extruder with 0.8 mm diameter holes. Pellets thus obtained were dried in the hot sun and stored in airtight polyethylene container to prevent fungal contamination.
Experimental procedure
The feeding trial was conducted in circular plastic trough for a period of 60 days. Each experiment was tried in triplicates. Each diet was randomly assigned to replicate groups of fish and fed by hand once a day. During the experimental period, fishes in control and different treatments were initially fed at a rate of 5% of body weight per day (dry-matter basis), which approached apparent satiation. The feeding rate was gradually reduced among all dietary treatments over the course of the experiment to ensure a rate close to apparent satiation without over feeding. The unutilized feed and faecal matter were collected before each morning feeding and stored for further analysis. Half of the water in the tanks was replaced daily throughout the experimental period after siphoning out the leftover feed and faecal matter.
Growth parameters
Weight and length of the control and experimental fishes were taken just before starting the experiment, followed by 15 days interval till the end of the experiment. The growth parameters in terms of weight gain, length gain and specific growth rate (weight) were evaluated as follows.
Final weight (gm) - Initial weight (gm) Percentage weight gain = ---x 100 Initial weight (gm)
Final length (cm) - Initial length (cm) Percentage length gain =--- x 100 Initial length (cm)
In Final weight (gm) - In Initial weight (gm) Specific growth rate = --- x 100 (weight) (% day -1) Days of experiment
Biochemical analyses
Estimation of feed utilization efficiencies
Feed utilization efficiencies in terms of feed conversion ratio (FCR), protein efficiency ratio (PER), protein productive value (PPV) and feed efficiency (FE) were estimated after 60 days of the experimental period in C.catla fed with control and different experimental feeds.
Feed conversion ratio (%)
Feed given* Feed conversion ratio = ---x100 Weight gain** *As fed basis i.e., dry weight
* * Wet or fresh weight gain
Protein efficiency ratio (%)
Weight gain (gm)
Protein efficiency ratio = --- x 100 Protein intake (gm)
Protein productive value (%)
Pb – Pa
Protein productive value = ---X 100 Pi
Where,
Pb = Total body protein at the end of the feeding trial Pa = Total body protein at the beginning of the feeding trial Pi = Amount of protein consumed over the feeding trial
Feed efficiency (%)
Weight gain (gm) Feed efficiency = -- --- X 100 Feed intake (gm)
Statistical analysis
The results of the entire study were analysed statistically using one way ANOVA and the level of significance was defined at P<0.05.
RESULTS
Growth performance
Probiotics incorporation improved the protein, carbohydrate and fat contents in all the experimental feeds than the control feed (table 1). Among the different probiotics supplemented feeds highest protein (35.58%), carbohydrate (13.46%) and fat contents (14.93%) were recorded in 3 g kg−1 probiotic incorporation. The lowest protein, carbohydrate and fat contents were estimated in the control feed (34.12, 12.81 and 14.01% respectively).
Weight gain, length gain and specific growth rate (weight) of the control and experimental fishes during different days (15, 30, 45 and 60) of the experimental period are presented in table 2 to 4. Maximum weight gain (28.50, 56.17, 76.98 and 95.24%), length gain (18.02, 47.41, 86.01 and 107.98%) and specific growth rate (0.89, 1.33, 1.56 and 1.84%) were recorded in C.catla fed with 3 g kg−1 diet and minimum weight gain (12.06, 21.51, 36.18 and 43.16%) was recorded in the control fishes (Significant at P<0.05).
Biochemical composition
Water content, protein, carbohydrate, fat, ash and calorific content in the muscle tissues of C. catla fed with control feed and different probiotics supplemented feeds were estimated before and after the experimental period (table 5). Protein, carbohydrate and fat contents recorded in the muscle tissues of experimental fishes before experiment were found to be 17.62, 4.53 and 2.45% respectively. After 60 days feeding of the experimental diets, fishes grown in different treatments showed significantly (P<0.05) highest protein, carbohydrate and fat content values. Of all the different treatments 3 g kg−1 fishes obtained maximum values of protein (19.93%), carbohydrate (6.24%) and fat contents (3.45%), whereas minimum values of 18.58, 4.85 and 2.73% were analyzed in the control fishes.
Before starting of supplementary feeding calorific content estimated in C. catla was 139.14 Kcal/gm. After the experimental period calorific content was increased in all the experimental fishes and maximum value (170.78 Kcal/gm) was noticed in 3 g kg−1 fishes and the minimum calorific content (150.61 Kcal/gm) was noticed in the control fishes. 71.73 and 1.92% of water and ash contents were observed in the muscle tissues of experimental fishes before experimental period. On 60th day of the experiment 3 g kg−1 fishes showed highest water and ash contents (77.63 and 3.14%) and lowest values of 72.75 and 2.33% were noticed in the control fishes than the other treatments.
Feed utilization efficiencies
Feed conversion ratio in C. catla fed with different probiotic supplementation at the end of the experimental period showed a variation between 1.48 to 2.156%. Among the different treatments and control, maximum feed conversion ratio (2.21%) was recorded in C.catla grown in the control and minimum (1.48%) was recorded in fishes fed with 3 g kg−1 Eubioz supplemented diet. Protein efficiency ratio of C. catla ranged between 2.014 to 2.68%, highest protein efficiency ratio (2.68%) was recorded in 3 g kg−1 fishes and lowest (1.71%) was noticed in fishes grown in control feed.
Probiotics incorporated diet fed fishes showed significantly (P<0.05) higher protein productive value ranged between 3.72 to 6.22% than the control fishes (3.11%). Of all the different treatments maximum protein productive value (6.21%) was recorded in C. catla grown in 3 g kg−1 feed and lowest (3.11%) was obtained in the control fishes. Feed efficiency of C. catla was varied from 24.11 to 62.82% and maximum feed efficiency (62.82%) was observed in 3 g kg−1 fishes and minimum (24.11%) was recorded in fishes grown in control. When compared to control significant (P<0.05) feed utilization efficiency values were found in the fishes fed with different probiotics incorporated feeds (table 6).
DISCUSSION
experimental diets prepared from different probiotics were well accepted and ingested by the experimental fishes. Hence, the palatability of the test diets was not affected by the use of probiotics as supplement. Microbial feed supplementation Eubioz, which contains L. acidophilus, S. thermophilus and S. boulardii improved the growth performances and decreased the feed conversion ratio in C.catla. The results were consistent with the results of previous researches. A compound additive containing lactic acid bacteria, L.acidophilus, S. faecium and S. cerevisiae were proved to increase the protein and fat absorption, decrease feed conversion ratio and reduce disease in fishes (Lara-Flores et al., 2003). Taoka et al., (2006) also observed that mixed strains of probiotics (B.subtilis, L.acidophilus, C.butyricum and S.cerevisiae) stimulated the food digestibility and non-specific immune response by improving its enzyme activity such as lysozyme and protease.
The present results showed that feed utilization efficiencies were increased in probiotics supplemented diet fed fishes than the control fishes, because probiotics increased the digestive ability by producing extra cellular enzymes such as proteases, lipases and necessary growth factors. The present findings were coincided with the results of Song et al., (2006) and Yang (1998), who reported enhanced feed utilization efficiencies in Miichthys miiuy fed with dietary Clostridrium butyricum, which influenced digestive enzyme activity. Dietary administration of S.faecium M74 135 improved the intestinal microflora and digestive enzyme activity (protease and lipase), resulted in highest feed utilization efficiencies and muscle proximate composition in Cyprinus carpio (Bogut et al., 1998).
A mixture of bacterial strains (Lactobacillus, Streptococcus and Saccharomyces sp.) positively influenced the growth and biochemical composition in C. catla by improving the nutritive value of the food, digestion and assimilation ability. Similar results were documented by Balcazar (2003) in Litopenaeus vannamei fed with supplemented diet contains mixed cultures of Bacillus and Vibrio sp., which improved the nutritive value of the food by supplying vitamins and fatty acids. In addition, Ziaei-Nejad (2006) showed that dietary administration of Bacillus sp. induced the food absorption and growth performances by enhancing protease levels. The increased nutritional indices found in the experimental fishes probably indicated that supplemented diets induced the feed intake, protein and fat absorption. Yu et al., (2008) also reported increased biochemical composition in L.vannamei fed with dietary Bacillus which can produce glucosidase enzymes and thereby it increased the digestion, feed utilization efficiencies and absorption. Probiotics may stimulated the activity of hydrolytic enzymes including proteases and amylases, which positively influenced the weight gain, specific growth rate and feed efficiencies in C. catla fed with commercial probiotics, Eubioz, which contains bacterial and yeast cultures.
Live yeast culture, S. cerevisiae improved the nutritional value of the experimental feeds and also enhanced the muscle proximate composition of the experimental fishes. Yeast cultures can involve in the production of vitamins such as vitamin B12 and biotin. Yeast supplementation may also stimulate amylase secretion and brush border enzymes, thereby it influenced the digestion and feed intake in the experimental fishes. Oliver-Novoa et al., (2002) showed that dietary supplementation of torula yeast, Candida utilis to Nile tilapia,
O.niloticus improved the nutritional indices and feed utilization efficiencies due to the production of vitamins and amino acids and enhanced the digestive metabolism by the secretion of a -amylase enzyme.
Probiotic strains (L. acidophilus and L.sporogens) found to have inhibitory effect on gram-negative bacteria present in the gut microflora of M. rosenbergii post larvae and improved the growth rate (weight gain and specific growth rate) and feed utilization efficiencies (Venkat et al., 2004). The present results indicate that the use and application of probiotics is very promising, cost effective feed supplement to carp feed manufacture.
Table 1 Protein, carbohydrate and fat contents (%) in the control and probiotic supplemented feeds.
Feed Concentrations
(g kg−1) Protein Carbohydrate Fat
Control --- 34.12 12.81 14.01
Eubioz
1 35.46 13.25 14.63
2 35.54 13.36 14.87
3 35.58 13.46 14.93
SED 0.0133 0.0050 0.0054
CD (0.05) 0.0274 0.0102 0.0110
Values are the mean of three replicates
Table 2 Weight gain (%) in Catla catla during different days of the experiment in the control and probiotic supplemented
feeds.
Feed Concentrations
(g kg−1)
No. of days during experiment
15 30 45 60
Control --- 12.06 21.51 36.18 43.16
Eubioz
1 22.06 49.24 66.14 86.51
2 26.14 53.04 74.74 92.92
3 28.50 56.17 76.98 95.24
SED 0.0081 0.0166 0.0245 0.0302
CD (0.05) 0.0167 0.0341 0.0504 0.0621
Values are the mean of three replicates
Table 4 Specific growth rate in percentage (weight) in Catla catla during different days of the experiment in the control and
probiotic supplemented feeds.
Feed Concentrations
(g kg−1)
No. of days during experiment
15 30 45 60
Control --- 0.26 0.69 1.15 1.18
Eubioz 1 0.75 1.23 1.40 1.78
2 0.86 1.28 1.54 1.83
3 0.89 1.33 1.56 1.84
SED 0.0003 0.0004 0.0006 0.0006
CD (0.05) 0.0006 0.0009 0.0011 0.0013
Values are the mean of three replicates
Table 3 Length gain (%) in Catla catla during different days of the experiment in the control and probiotic
supplemented feeds.
Feed Concentrations
(g kg−1)
No. of days during experiment
15 30 45 60
Control --- 8.11 14.19 17.27 27.76
Eubioz
1 14.11 30.52 44.12 59.22
2 17.15 44.42 82.81 98.21
3 18.02 47.41 86.01 107.98
SED 0.0053 0.0131 0.0238 0.0301
CD (0.05) 0.0110 0.0270 0.0488 0.0618
Table 5 Biochemical composition in muscle tissues of Catla catla before and after experimental period
Feed Concentrations
(g kg−1)
Moisture (%)
Protein (%)
Carbohydrate (%)
Fat (%)
Ash (%)
Calorific Value (Kcal/gm)
Eubioz
1
73.75 75.9 77.63
19.13 19.57 19.93
4.13 3.04 2.80 157.76
2 75.90 19.57 5.98 3.36 3.20 166.80
3 77.63 19.93 6.24 3.45 3.14 170.78
SED 0.0009 0.0003 0.0006 0.0003 0.0009 0.0016
CD (0.05) 0.0018 0.0006 0.0014 0.0006 0.0019 0.0039
Values are the mean of three replicates
Table 6 Feed utilization efficiencies (%) of Catla catla in the control and probiotic supplemented feeds.
Feed
Concentrations (g kg−1)
(%)
FCR (%)
PER (%)
PPV (%)
FE (%)
Control --- 2.21 1.71 3.11 24.11
Eubioz
1 1.93 2.25 4.47 49.81
2 1.59 2.52 5.02 58.11
3 1.48 2.68 6.21 62.82
SED 0.0007 0.0009 0.0018 0.0191
CD (0.05) 0.0014 0.0018 0.0036 0.0392
Values are the mean of three replicates
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