| Author | Shivappa, Raghunath B. |
| Call Number | AIT Thesis no. AS-97-11 |
| Subject(s) | Shrimp culture
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. AS-97-11 |
| Abstract | The excessive and often indiscriminate use of antibiotics in aquaculture industry has
become ineffective and self defeating with growing evidence of the development of resistant
pathogens. Probiotics, immunoenhancers and vaccines are evolving as new management
strategies to control bacterial diseases. A study was carried out to determine the efficacy of
probiotics and the disinfectant, benzalkonimum chloride in controlling luminescent bacteria
(Vibrio harveyl).The study aimed at exploring the possibilities to either replace or mimimize
the use of antibiotics by using probiotics and disinfectants in shrimp hatcheries.
MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal
Concentration) tests were carried out for four disinfectants namely benzalkonim chloride
(BKC) copper sulfate, formalin and povidone iodine in order to select the most effective
disinfectant. BKC was found to be the most effective chemical with lowest MBC value and
lowest cost to achieve MIC and MBC. Povidone iodine was found to be the least effective
chemical from both technical and economic perspectives.
The efficacy of BKC and probiotics was then tested on Penaeus monodon with six
treatments under normal and two stressed conditions. Shrimps were challenged with V. harveyi
at a concentration of 5xl07 cfu/mL, probiotic suspension and BKC were added at a
concentration of 10 ppm and 1 ppm respectively to control the pathogen in all the experiments.
Survival was monitored over a period of 72 hours. It was found that survival was significantly
higher (P<0.05) under normal conditions in the probiotic treatments suggesting a possibility of
its effective use in the industry . Under stressed conditions, it was found that survival was not
significantly different in probiotics and BKC treatments using ANOVA but sign test indicated
that use of probiotic was effective in controlling V. harveyi under temperature stress and not
under salinity stress.
It was found that BKC treatments did not have a significant effect under all
conditions. Fluctuations in environment was found to have a significant effect on the virulence
of V. harveyi. Salinity stress proved more lethal than temperature stress. |
| Year | 1997 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. AS-97-11 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Aquatic Systems (AS) |
| Chairperson(s) | Hambrey, John; |
| Examination Committee(s) | Lin, C. Kwei ;Supranee Chinabut ; |
| Scholarship Donor(s) | Norwegian Agency for Development Cooperation
(NORAD); |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1997 |