Survival of Salmonella in septage-fed ponds and potential of tilapia as carrier of pathogenic organisms | |
| Author | Pongchan Ruamthveesub |
| Call Number | AIT Thesis no. AE-86-32 |
| Subject(s) | Tilapia Salmonellosis |
| Note | A thesis submitted in partial fulfillment of the requirements for t he degree of Master of Science. School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | Microbiological studies of a septage loaded fish pond system were conducted. The die -off patterns of indicator bacteria, indicator virus and Salmonella were studied by examining the number of organisms present in water before and after loading into fish ponds. The reduction in number was found to occur immediately and the number of organisms decrease d to original levels 48 hrs after loading. The infection of S. typhimurium to Nile tilapia at various pathogenic levels CLDso, 10 LD50, 100 LD50 or 3x10 4 , 3x10 5 and 3x10 6 cells/ml) was studied by introducing the .organisms into the water in aquaria containing fish. Fish were examined for active S. typhimurium on days 7, 14, 21, 28 and 56 of exposure. The results indicated that fi s h digestive tract was the most susceptible organ to infection and a lesser degree in spleen, liver, meat, bile and blood. The infection of~ typhimurium was found in meat at the level of 3x10 5 cells/ml of aquarium water after 14 days of exposure . The antibody titre of Nile tilapia was determined by using the passive hemagglutination test. It was found t h at this fish developed a specific antibody against S. typhimurium but the titre was relatively low and did not indicate active infection by bacteria. The positive titre indicates recent experience of fish to this bacterium. From a public health point of view fish raised in septage did not have the potential for transmission of the organisms present in septage to consumers since the number present in the water was lower than that the densities required to infect the fish. |
| Year | 1986 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Edwards, Peter |
| Examination Committee(s) | W. Chaicumpa ;Wee, Kok Leong |
| Scholarship Donor(s) | Government of Australia |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1986 |