ISOLATION, IDENTIFICATION, ENZYMATIC POTENTIAL AND ANTIMICROBIAL SUSCEPTIBILITY OF BACTERIA ASSOCIATED WITH FISH FEED

ABSTRACT

 This study was done to determine isolates from five brand of fish feeds (Top,Eco,Alleraqua,Blue crown and Nsun). The samples were collected from Ndoro market, and Umuahia main market, with sterile containers. A total of 50 samples were collected from the two different markets in Umuahia, and was analysed in the laboratory by standard microbiological methods. A total of 38 bacteria (Staphylococcus aureus, E.coli, Bacillus substilis, Salmonella spp, Proteus mirabilis, Shigella spp and Klebsilla spp) were isolated from the fish feed samples. Results showed that Eco fish feed had the highest bacterial load of 7.2 x 105cfu/g, E.coli had the highest prevalence of 35% in fish feed, Results showed that the fish feed sold at Ndoro, Umuahia in Abia State has the highest occurrence of bacteria in them. The enzymatic activities of the feed in the results proved that the protease and lipase activities are essential for the utilization of protein and lipid in Shigella spp and E.coli ranging from 0.962 ± to 1.224 ± and 2.058 ± to 2.307 ± respectively. These corresponds to the high growth of the fishes. Amylase activity proved the need for the hydrolysis of carbohydrates respond to the level of dietary carbohydrate to starch - rich feed. Also in the study of the antibiotic test showing the presence of resistance strains in fish feed, it was observed that S.typhi isolates were resistant to tetracycline and erythromycin. The antibiotics (ciprofloxacin, norfloxacine, gentamycin, amoxil, streptomycin, erythromycin, ampiclox etc.) used in this study are commonly used clinically in Umuahia to treat infected humans. Feeds contaminated with pathogenic microbes such as Salmonella, should be decontaminated before use or destroyed out rightly. 

TABLE OF CONTENTS

Title ﾿ i

Dedication ﾿ ii

Acknowledgement ﾿ iii

Table of contents ﾿ iv

List of tables ﾿ vi

List of figures ﾿ vii

Abstract ﾿ viii

CHAPTER ONE

INTRODUCTION

1.1 ﾿ Background of the Study ﾿ 1

1.2 ﾿ Statement of the Problem ﾿ 2 

1.3 ﾿ Objectives of the Study ﾿ 2

CHAPTER TWO

LITERATURE REVIEW

2.1 ﾿ Definition of Fish Feed ﾿ 3

2.1.1 ﾿ Types of Fish Feed ﾿ 3

2.2 ﾿ Nutrition Value Fish Feed ﾿ 6

2.2.1 ﾿ Proteins and Amino Acids 6

2.2.2 ﾿ Lipids ﾿ 7

2.2.3 ﾿ Carbohydrates ﾿ 7

2.2.4 ﾿ Vitamins and Minerals ﾿ 7

2.2.5 ﾿ Pigment ﾿ 7

2.2.6 ﾿ Binding Agents ﾿ 8

2.2.7 ﾿ Preservatives ﾿ 8

2.2.8 ﾿ Attractants ﾿ 8

2.2.9 ﾿ Other Feed stuffs ﾿ 8

2.3 ﾿ Feed Preparation ﾿ 9

2.4 ﾿ Bacteria associated with Fish Feed ﾿ 10

2.5 ﾿ Bacteria associated with farmed fish ﾿ 11

2.6 ﾿ Factors Contributing to Fish Contamination ﾿ 13

2.7 ﾿ Antimicrobial Resistance ﾿ 14

CHAPTER THREE

MATERIALS AND METHODS  

3.1 ﾿ Sample Collection ﾿ 16

3.2        Media Preparation                                                                                                     16

3.2.1 ﾿ Enumeration and Isolation of Bacteria from Fish Feed Sample                                16                       3.2.2    Identification of Isolates                                                                                             16                                                      

3.3 ﾿ Gram Staining ﾿ 17

3.4 ﾿ Motility Test by Hanging Drop Method ﾿ 17

3.5 ﾿ Biochemical Tests ﾿ 18

3.5.1 ﾿ Catalase Test ﾿ 18

3.5.2 ﾿ Coagulase Test (Slide test) ﾿ 18

3.5.3 ﾿ Oxidase Test ﾿ 18

3.5.4 ﾿ Citrate Utilization Test ﾿ 19

3.5.5 ﾿ Indole Test ﾿ 19

3.5.6 ﾿ Voges-Proskauer Test ﾿ 20

3.5.7 ﾿ Methyl Red Test ﾿ 20

3.6 ﾿ Purification of Isolate ﾿ 21

3.7 ﾿ Qualitative Screening of Enzyme Producing Isolates ﾿ 21

3.7.1 ﾿ Purification of Enzyme Isolates ﾿ 21

3.7.2 ﾿ Production of Amylase Enzyme ﾿ 21

3.7.3 ﾿ Production of Lipase Enzyme ﾿ 21

3.7.4 ﾿ Screening of Isolates for the Pectinase Activity ﾿ 22

3.8 ﾿ Antimicrobial Susceptibility Tests ﾿ 22

CHAPTER FOUR

RESULTS AND DISCUSSION 

4.1 ﾿ Results ﾿ 24

4.2 ﾿ Discussion ﾿ 33 ﾿

CHAPTER FIVE

CONCLUSION 

5.1 ﾿ Conclusion ﾿ 37

REFERENCE 

LIST OF TABLES

Table                                                                  Title                                                                   Page    

4.1   Identification and Characterize of Bacterial Isolate from Fish Feed Samples        ﾿        25

4.2   Mean Microbial Count from Fish Feed Sample ﾿        26                  

4.3   Distribution of Bacterial Isolates from Fish Feed Samples ﾿        29

4.4  Percentage occurrence of Bacterial isolates from fish feed samples ﾿                    30

4.5   Enzymatic activities and zone of inhibitions ﾿                                31

4.6  Antibiotic susceptibility tests of bacterial isolates from fish feed samples                            32