The effect of selected herb extracts on Aeromonas Hydrophila isolated from hybrid catfish (Clarias macrocephalus x C. gariepinus) | |
| Author | Tu Thanh Dung |
| Call Number | AIT Thesis no.AE-96-17 |
| Subject(s) | Catfishes Fishes--Feeding and feeds |
| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Science |
| Publisher | Asian Institute of Technology |
| Abstract | A series of sensitivity test were carried out to test the effect of eight selected herb extracts on 6 strains of Aeromonas hydrophila isolated from hybrid catfish (Clarias macrocephalus x C. gariepinus). The results showed that only two herbs were sensitive Phyllanthus debitis (PD) and Eugenia caryophyllus (EC). They were found to have minimum inhibitory concentration (MIC) at 10,000 µg/ml in PD powder herb extract and 1,000 µIll in EC oil extract. An acute bioassay was conducted to determine the toxicity of PD and EC to hybrid catfish (5.6 g). The 12, 24, 48, 72, 96 hours LC50 value for EC oil on hybrid catfish were 25.05; 20.56; 18.48; 16.78; 15.11 µ1/1 respectively. In the contrast, PD was considered no toxicity on hybrid catfish during 96 hours at 20,000 µ111. Based on the results of MIC and LC50, an experiment was set up in the aquariums to evaluate PD and EC extracts for prevention motile Aeromonas septicemia on hybrid catfish by oral and bathing application methods. For EC extract, the palatability of medicated feed was lower than 10 ml/kg feed. Therefore, EC concentration in feeding was 1 ml/kg feed (approximately MIC value). For bathing was at safe concentration (4.48 µ111) for prolong bathing due to MIC value was higher than safe concentration In PD, safe concentration was higher than MIC value. Therefore, PD extract was used at 10 g/kg feed (approximately MIC value) in feeding at 1,000 µg/ml (reducing 10 times of MIC value) in prolong bathing. In this experiment, fish were fed herbal medicinal feed during 10 days before injecting bacterial suspension. Mortality rate were no significant difference at (P< 0.05) in both EC oil bathing and feeding. In the contrast, there was significant difference at (P> 0.05) of PD in both 2 methods. However, in PD extract, using feeding was more effective than bathing administration. EC is not suitable for bathing prolong to treat bacterial disease on hybrid catfish. |
| Year | 1996 |
| 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 Food Engineering (AE) |
| Chairperson(s) | Hambrey, John;Supranee Chinabut; |
| Examination Committee(s) | Little, David C.; |
| Scholarship Donor(s) | DANIDA; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1996 |