, Diagnosis an-&& of Shrimp Diseases - Central Institute of ...

More documents

Recommendations

Info

step would be to determine the route of administering the strain either by bath or by 111ixillgwith the feed. Finally economic evaluation has to be done to see whether it is worth theinvestment.ImnzunostimulffntsThe Invertebrates encounter all the usual sorts of challenges to self-integrity. Theirhabitats are laden with infectious agents: viruses, bacteria, fungi, protists, and other animals.Shrimps have innate defense systems, including the phagocytic cells, production of toxicoxygen and nitrogen metabolites, and melanization pathways, use of RNA interference(RNAi), pattern-recognition receptors (PRRs), anti-microbial peptides (AMPS), whicheffectively help in combating infection. However, with the advancement in aquacultilretechnology, application of extraneous substances to boost immune system of shrimps hascome into practice. These are usually chemical substances, which aid animals (shrimp) indefending themselves against disease outbreaks and are called immunostimulants. P-1, 3 1 1,6- glucans have been reported to be most promising substances with i~n~nunosti~nulatoryproperlies. A number of other substances, such as laminarin, chitosan, saponins, barleyglucans, lactoferrin, zymosan, dextran, peptidoglycans (PG), lipopolysaccharides (LPS),inulin, levamisole, herbal extracts, etc. are also reported to he useful in enhancing shrimpimmune system.Plz age Tlz empyWith the developn~ents in aquaculture and associated disease outbreaks, use of antibioticsand therapeutants has also substantially increased over the years. Bacteria resistant to most orall available antibiotics are increasingly causing serious problems, raising widespread fearsof returning to a pre-antibiotic era of untreatable infections and epidemics. As an alternativeto the use of antimicrobial agents against the pathogenic bacteria, the possibilities of using aspecific kind of virus that attack only pathogenic microorganisms (phage therapy) appears tobe promising. Almost a century ago, Hankin had reported that the waters of the Ganges andJamuna rivers in India had marked antibacterial action, which could pass through a very fineporcelain filter. He also had reported that boiling destroyed this activity. He partic~~larlystudied the effects 011Vibrio cholerae and suggested that the s~tbstance responsible keptcholera epidemics from spreading by ingestion of the water of these rivers. This filterablesitbstance was nothing but the viruses (called as bacteriopl~ages) that specifically affectedYibrio cholerae and brought about their lysis and killing. This and several initial studies gave
irth to a new concept to treatment of disease: "Phage therapy". Phage therapy was triedextensively and many successes were reported for a variety of diseases, including dysentery,typhoid and paratyphoid fevers, cholera, and pyogenic (pus-producing) and urinary-tractinfections. Phages were poured directly into lesions, given orally or applied as aerosols orenemas. Similar approach could be incorporated in the therapy of bacterial diseases in theaquaculture systems. We need to create phage banks by isolating and characterisingbacteriophages specific to bacterial pathogens that are encountered in the aquaculti~resystems and evaluate their efficacy. Phages of some fish pathogenic bacteria, such asAeronzonas salmonicida, A. hydrophila, Edwardsiella tarda and Yersinia ruckeri, have beenreported. However, application of phage therapy in aquaculture requires a great deal ofresearch.Specific pathogen free (SPQIhigh health stockThe concept of specific pathogen free / high health stock has been developed in orderto tackle the growing disease problenls in penaeid aquaculture. U.S. Marine shrimp farmingprogram has adopted this cincept. The specific pathogen free stock is the one which isdeveloped as free from certain pathogens, such as viruses and protozoan parasites. Forpractical purposes, captive populatioiis of selected L. vannamei maintained in the oceanicInstitute nucleus- breeding center is referred to as SPF. However, the putative advantages ofstock could be useful in conjunction with proper husbandry practices to tackle the diseaseproblems. Most of the shrimp aquaculturists consider the SPF stock as panacea for diseasecontrol. There is no specific evidence to show the advantage of SPF stock in the control ofmajor disease such as viral disease. According to Lightner, there is no criltured penaeidwhich shows any type of disease resistance to the most dreaded viral disease, the white spotvirus syndrome (WSSV). However, the SPF L. vannamei is projected as a disease resistantstock to tide over the problem of WSSV. This approach of introduction of nonnative specieshas to be viewed with caution, especially in countries such as India, where native speciessuch as Fenneropenaeus indicz~s, the Indian white shrimp is already existing and consideredas candidate species along with P. monodon.
Page 5 and 6:
OVERVIEW OF STRATEGIES FOR PREVENTI
Page 7 and 8:
in harmonizing aquatic animal healt
Page 9 and 10:
SI-IRXMP DISEASES: GENEIL4L ASPECTS
Page 11 and 12:
quantitative level of pathogen is i
Page 13 and 14:
presence of prominent eosinophiiic
Page 15 and 16:
Disease affected the shrimps of all
Page 19 and 20:
BACTERIAL AND FUNGAL DISEASES OF SH
Page 21 and 22:
Cause: The epibiotic bacteria stich
Page 23 and 24:
PARASiTIC AND NON-INFECTIOUS IIISEA
Page 25 and 26:
XOS-INFECTIOUS DISEASESNon-infectio
Page 27 and 28:
INVESTIGATING SHRIMP DISEASES: OBSE
Page 29 and 30:
lnay be a predisposing factor for b
Page 31 and 32:
BACTERIOLOGICAL METHODSS.V. Alavand
Page 34 and 35: In place of ZMA, nutrient agar prep
Page 36 and 37: Interpretation: Positive reaction i
Page 38 and 39: Incubate at 37°C for 1-2 h.Examine
Page 40 and 41: Alkaligens: etc. are resistant. The
Page 42 and 43: Culture Media, Reagents and StainsC
Page 45 and 46: Differential characteristics of Vib
Page 47 and 48: Davidson's Alcohol Formatin Acetic
Page 49 and 50: Paraffin cold impregnationXylene an
Page 51 and 52: ProcedureDe-paraffinise the slid'c
Page 53 and 54: Biochemistry of Nucleic Acids with
Page 55 and 56: DNA e.rl1i6it.v base equivuleizcc!E
Page 57 and 58: hydrolyzed by dilute alkali. The su
Page 59 and 60: Polymerase Chain Reaction (PCR) is
Page 61 and 62: a number of viral, bacterial and pa
Page 63 and 64: from 15-30 bases. Negative controls
Page 65 and 66: PCR Primers for Indian WSVTwo sets
Page 67 and 68: ANTIOXIDANTS IN MANAGEMENT OF OXIDA
Page 69 and 70: Many potent chemical carcinogens ar
Page 71 and 72: cells. It has been shown that possi
Page 73 and 74: AFB, induced ~nutagenesis in Salmon
Page 75 and 76: FIGURE 2. An overview of oxygen rad
Page 77 and 78: were responsible for production los
Page 79 and 80: for Asiatic region. The participati
Page 81 and 82: charge of the DNA fragment. The neg
Page 83: European countries have in place th
show all

, Diagnosis an-&& of Shrimp Diseases - Central Institute of ...

Create successful ePaper yourself

Delete template?

Save as template?