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20204
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Subject: Aquaculture × End date: 2020 × Start date: 2020 × Type: Thesis ×
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    ThesisItemOpen Access
    CHARACTERIZATION AND ANTIMICROBIAL RESISTANCE OF AEROMONAS SPECIES ISOLATED FROM CULTURED FRESHWATER FISHES
    (SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2020-12) SRUTHI, PERLA; Neeraja, T (MAJOR); Haribabu, P; Balasubramanian, A
    Pathogenic Aeromonas species are causing significantly high mortalities and economic losses among the cultured freshwater fish in India and Andhra Pradesh. The aim of the present study was to identify the Aeromonas species isolated from cultured freshwater fishes majorly exhibiting bacterial haemorrhagic septicaemia, abdominal dropsy, tail rot and fin rot in two districts viz., West Godavari and SPSR Nellore districts of Andhra Pradesh, India. The diseased fish species collected from farms were Catla catla (catla), Labeo rohita (rohu), Piaractus brachypomus (pacu) and Pangasius hypophthalmus (pangas). Further, the resistance of the isolated Aeromonas spp. to the currently available antimicrobial therapeutics was determined. In the present study, 15 species of Aeromonas were isolated viz., Aeromonas allosacharrophila (n=3), A. aquariorum (n=2), A. caviae (n=1), A. enchelia (n=1), A. jandaei (n=3), A. media (n=2), A. molluscorum (n=3), A. piscicola (n=1), A. popoffii (n=3), A. sobria (n=3), A. schubertii (n=6), A. tecta (n=9), A. trota (n=3), A. veronii biovar sobria (n=5) and A. veronii biovar veronii (n=13). The Aeromonas species isolated on RS medium and GSPA medium were identified and characterized by conventional biochemical tests. The study on prevalence of Aeromonas spp. was carried out for a period of 7 months from September 2019 to March 2020 in the above two districts revealed that the highest prevalence was recorded in A. veronii bv. veronii. Significantly higher prevalence (P 0.05) with the latter species. Further, prevalence of Aeromonas spp. were significantly different (p <0.05) with respect to fish species and geographic location. In vitro antibiotic resistance study revealed that all the isolates of 15 Aeromonas spp. were highly resistant to ampicillin, amoxyclav and oxytetracycline. Further, all the Aeromonas spp. were found multiple antibiotic resistance (MAR). The MAR index of more than 0.2 was observed in all the isolates of Aeromonas spp. except A. piscicola. It indicates that these Aeromonas spp. might have originated from high risk sources of contamination. Haemolytic activity assay revealed that A. veronii bv. sobria (60%), A. aquariorum (50%), A. jandaei (33.3%), A. sobria (33.3%) and A. tecta (22.22%) were found to be β-haemolytic. However, majority of the Aeromonas spp. isolates were found α- haemolytic.
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    ThesisItemOpen Access
    SURVEILLANCE ON BACTERIAL DISEASES OF CULTURED INDIAN MAJOR CARPS IN ANDHRA PRADESH, INDIA
    (SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2020-06) SRIVIDYA, R; Neeraja, T(MAJOR); Haribabu, P; Dhanapal, K
    Bacterial fish diseases were considered to be the main cause of high mortalities and economic losses among the cultured freshwater fish in Andhra Pradesh. The aim of the present study was to identify the bacterial strains isolated from farm raised Indian major carps majorly exhibiting bacterial haemorrhagic septicaemia, abdominal dropsy, tail rot and fin rot in two districts viz., SPSR Nellore and West Godavari districts of Andhra Pradesh, India. Further, the susceptibility of the isolated bacterial strains to the currently available antimicrobial therapeutics was determined. In the present study, the pathogenic bacteria isolated were species of Aeromonas, Pseudomonas and Enterobacteriacea family. 7 species of Aeromonas viz., Aeromonas hydrophila, A. tecta, A. caviea, A. sobria, A. veronii A. schubertii and A. encheleia; 4 species of Pseudomonas viz., Pseudomonas sp., Pseudomonas stutzeri, P. diminuta and P. fluoroscenes; 5 species of Enterobacteriacea family viz., Citrobacter freundi, Serratia rubidaea, S. fonticola, Klebsiella pneumoniae ssp pneumniae and Enterobacteriacea group were identified and characterized by conventional biochemical tests. The prevalence study carried out for a period of one year from July 2018 to June 2019 in the above two districts revealed the dominance of aeromoniasis caused by Aeromonas spp. Significantly higher prevalence (P 0.05) with that of aeromoniasis. Further, prevalence of bacterial diseases did not vary significantly (P > 0.05) with respect to fish species, geographic location and seasonality. In vitro antibiotic sensitivity study revealed that gentamicin, ciprofloxacin, amikacin and trimethoprim were found to be more effective against Aeromonas sp., Pseudomonas sp. and Enterobacteriaceae family. Multiple antibiotic resistance (MAR) study showed that all the species of Pseudomonas and Enterobacteriaceae family were MAR. Among Aeromonas sp., A. tecta and A. caviea were 100% MAR, however 80% of A. sobria, A. veronii and A. schubertii showed MAR and 50% of A. hydrophila strains only showed MAR. The MAR index of more than 0.2 was observed in all the bacterial strains of Aeromonas, Pseudomonas and Enterobacteriaceae family indicated that these bacterial strains might have originated from high risk sources of contamination. Haemolytic activity assay revealed that A. veronii (80%), A. schubertii, (60%), A. sobria (40%) and A. tecta (33.3%) were found to be β-haemolytic.
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    ThesisItemOpen Access
    EFFECT OF DIETARY MINERAL SUPPLEMENTATION AT DIFFERENT SALINITIES ON GROWTH AND SURVIVAL OF LITOPENAEUS VANNAMEI (BOONE 1931)
    (SRI VENKATESWARA VETERINARY UNIVERSITY, TIRUPATI - 517 502, ANDHRA PRADESH (INDIA), 2020-10) PAMANNA, DASARI; RAVINDRA KUMAR REDDY, D (MAJOR); CHANDRASEKHARA RAO, A; SUDHAKAR, O; MADHAVI, K
    The present study on “Effect of dietary mineral supplementation at different salinities on growth and survival of Litopenaeus vannamei (Boone, 1931).” was conducted in the Wet Laboratory of the Department of Aquaculture, College of Fishery Science, Sri Venkateswara Veterinary University, Muthukur for a period of 125 days (including acclimatization period of 34 days) and experiment 2 for a period of 28 days. In experiment 1, the Litopenaeus vannamei were fed with 4 different diets containing the various levels of Ca, Mg, K and Na in Diet 1(0.1% Ca, 0.01% Mg, 0.5% K and 0.5% Na), Diet 2 (0.2% Ca, 0.02% Mg, 1% K and 1% Na), Diet 3 (0.3% Ca, 0.03% Mg, 1.5% K and 1.5% Na) and Diet 4 (0.4% Ca, 0.04% Mg, 2% K and 2% Na) and control diet is without addition of extra minerals. The control and experimental diets with 35% protein using the ingredients such as fish meal, soya meal, deoiled ricebran and groundnut oil cake as major ingredients. Feeding was given at the rate 8% to 3% of shrimp body weight. The experiment was conducted in plastic tubs and maintained triplicates at 0, 5, 10 and 15 ppt salinity water. After completion of experiment, the highest average body weight gain of 18.27±0.01 g, the highest specific growth rate (SGR) 2.52±0.01, highest protein efficiency ratio (PER) 2.18±0.02 and lowest feed conversion ratio (FCR) 1.31±0.010 were recorded in the treatment Diet 2 (Ca 0.2%, Mg 0.02%, K 1% and Na 1%) and the lowest average body weight gain of 16.55±0.01 g was recorded in control (C) at 15 ppt salinity. The overall highest survival of 90% was found in Diet 2 (Ca 0.2%, Mg 0.02%, K 1% and Na 1%) and Diet 3 (Ca 0.3%, Mg 0.03%, K 1.5% and Na 1.5%) was recorded. There was a significant difference in weight gain, SGR, FCR and PER in L. vannamei fed with various levels of minerals incorporated diets compared to control diet fed group. In all the treatments Diet 2 (Ca 0.2%, Mg 0.02%, K 1% and Na 1%) showed better performance in terms of growth. The survival rate was better in the Diet 2 (Ca 0.2%, Mg 0.02%, K 1% and Na 1%) and Diet 3 (Ca 0.3%, Mg 0.03%, K 1.5% and Na 1.5%)for Litopenaeus vannamei. In experiment 2, Studies on essential mineral among Calcium, Magnesium, Potassium and Sodium individually supplemented through diet at 15 ppt salinity. The Litopenaeus vannamei fed with diets containing Ca 0.2% (DCa), Mg 0.02% (DMg), K 1% (DK) and Na 1% (DNa) individually and control diet without addition of extra minerals. The control and experimental diets with 35% protein using the ingredients such as fish meal, soya meal, deoiled ricebran and groundnut oil cake as major ingredients. Feeding was given at the rate 2% of shrimp body weight. The plastic tubs were maintained in triplicate. Important water quality parameters were recorded daily (Temperature, pH, Dissolved Oxygen, Total Hardness, Total Alkalinity, Total ammonia and Nitrite), Growth and Survival were recorded at weekly intervals. After completion of experiment, the highest average body weight gain of 5.30±0.04 g, the highest specific growth rate (SGR) 3.06±0.01 and lowest feed conversion ratio (FCR) 1.28±0.01 was recorded in the treatment supplemented with 1% K in diet (DK). The overall highest survival of 100% was recorded in diet 0.02% Mg (DMg). Therefore, these findings clearly indicate that inclusion of minerals in shrimp feed will have positive benefits in increasing growth and survival in Litopenaeus vannamei.
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    ThesisItemOpen Access
    EFFECT OF SELECTED HERBS ASHWAGANDHA (WITHANIA SOMNIFERA) AND SHATAVARI (ASPARAGUS RACEMOSUS) AS DIETARY SUPPLEMENTS ON GROWTH AND METABOLIC RESPONSES OF LITOPENAEUS VANNAMEI (BOONE, 1931)
    (SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2020-10) SRINIVASA RAO, APPANA; RAVINDRA KUMAR REDDY, D (MAJOR); CHANDRASEKHARA RAO, A; DHANAPAL, K; SUGUNA, T
    The present study on “Effect of selected herbs Ashwagandha (Withania somnifera) and Shatavari (Asparagus racemosus) as dietary supplements on growth and metabolic responses of Litopenaeus vannamei (Boone, 1931).” was conducted in the Wet Laboratory of the Department of Aquaculture, College of Fishery Science, Sri Venkateswara Veterinary University, Muthukur for a period of 127 days (including acclimatization period of 36 days). The experimental shrimps, Litopenaeus vannamei were fed on the diets containing Ashwagandha and Shatavari at 0.05%, 0.10% and 0.15% individually and in combination. The control diet is without Ashwagandha or Shatavari. The control and experimental diets were prepared to have almost similar crude protein level of 35% using the ingredients such as fish meal, shrimp meal, soya meal, deoiled rice bran, ground nut oil cake as major ingredients. The control and experimental tanks were maintained to have 15 ppt salinity water. Total experiment contained 9 treatments and one control maintained in triplicate. Important water quality parameters (Dissolved oxygen, Temperature, pH, Total ammonia and Nitrite), Growth and Survival were recorded at weekly intervals. The immunological parameters such as pro phenoloxidase, lysozyme and total serum/plasma protein were anlaysed at 60 days and 91 days of the experimental period. The digestive enzymes protease, amylase and lipase activity was analyzed at the end of the experimental period. The highest average body weight gain of 18.82 gm ±1.574 was recorded in the treatment AS1 that contained combination of Ashwagandha 0.05% + Shatavari 0.05% in diet and the lowest average body weight gain of 13.64 gm ±0.895 in control (C). The overall highest survival of 100% in AS1 and A1 and lowest survival of 73.33% in control (C) was recorded. There is significant difference in weight gain, Specific Growth Rate, Feed Conversion Ratio and Protein Effeciency Ratio for L. vannamei fed with various levels of Ashwagandha and Shatavari incorporated diets compared to control diet fed group. The immunological parameters 2 such as pro-phenoloxidase, Lysozyme & total serum/plasma protein and the digestive enzymes protease, amylase and lipase showed significant increase in all the treatment groups containing Ashwagandha and Shataavari in diet compared to the group fed with control diet. The Treatment AS1 that contained both Ashwagandha and Shataviari extracts each @ 0.05% was found significantly superior among all the treatments. Both Ashwagandha and Shatavari extracts showed better performance in terms of growth, digestive enzymes and immunological responses individually as well as in combination at rate of 0.05% inclusion level in the diet for Litopenaeus vannamei. Therefore these findings clearly indicates that inclusion of Ashwagandha and Shatavari extracts in shrimp feed will have positive benefits in increasing growth as well as immunity and approximately 27% extra profit to the marginal and small scale farmer in Litopenaeus vannamei.