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https://ptsldigital.ukm.my/jspui/handle/123456789/499842| Title: | Feeding and reproductive biology of false clownfish Amphiprion ocellaris (Cuvier, 1830) |
| Authors: | Khoo Mei Ling (P41540) |
| Supervisor: | Mazlan Abd. Ghaffar, Prof. Dr. |
| Keywords: | Clownfish Microenvironment Growth pattern Reproductive biology Dissertations, Academic -- Malaysia |
| Issue Date: | 2-Oct-2016 |
| Description: | A bloom in the ornamental fish industry has caused a decreased in the numbers of wild individuals of A.ocellaris in an alarming rate, thus concerns have been raised to culture this species in captivity for commercial and conservation purposes. Therefore, this thesis aimed to investigate the growth pattern, feeding and the reproductive biology of clownfish A.ocellaris, to elucidate the digestion process in the stomach of A.ocellaris and to look into the microenvironment of the clownfish host, the sea anemone H.magnifica. Biological studies of the clownfish A.ocellaris, as well as the daily productivity experiment of its host sea anemone H. magnifica has been carried out in the waters of Pulau Tioman. Length-weight relationship of A.ocellaris shows an isometric growth (b=3). Food items mainly consisted of zooplanktons and plant bits, shows that the fish is omnivorous and confirmed by trophic level analysis (2.98 ± 0.29) and relative gut length analysis (b=1). The gonads showed 4 stages of maturity with fecundity count of 23-1518. Oocytes were found in the matured testes but no spermatogenic cells in matured ovaries showed that the fish is a protandrous hermaphrodite and sex not reversible. Digestion physiological studies were carried out in the laboratory where the gastric emptying time was determined. A total of 36 hours needed for food to completely evacuate the stomach. Size of satiation meal increases in almost direct proportion to weight of fish (b=1.278). Regression analysis was used to evaluate the adequacy of 2 models; Anderson's [St = So(1-So (α-1)ρ(1-α)t)1/(1-α) + ξ ] and Grove's model [St = (So α – αKt)1/α ], in describing the gastric emptying rate. Grove's model provided a better fit with higher r2 value, with the calculated parameters of maximum meal size at time 0 (S0) = 0.195g and gastric emptying rate (K) = 0.0165 g hr-1. There was no initial delay phase as predicted and the evacuation followed a curve. Pepsin activity in the stomach showed rapid responses to food intake, where activity was detected at one hour after feeding and reached its peak at 2 hour after feeding. Pepsin activity decreased since then until the 12th hour after feeding where it reached the lowest point. An increase of pepsin activity was detected after that, where a small boost was detected at 24 hours after feeding to digest the remaining food item in the stomach before the pepsin secretion decreased and maintained at pre-feeding level. Fast response of digestive enzyme in stomach implied that clownfish is equipped to utilize infrequent and irregular meals effectively. The productivity of the anemone was measured in situ using a submersible diving PAM. The daily productivity of host anemone showed an opposite trend to the light intensity. The effective quantum yield and maximum quantum yield were 0.75±0.08 and 0.74±0.11, respectively. The diurnal variation showed that the anemone was most vulnerable during mid-day. The results of this study has provided valuable information fish biologist and aquarist to aid in developing a more effective management plans for the aquaculture and conservations for this fish.,Certification of Master's/Doctoral Thesis" is not available |
| Pages: | 124 |
| Publisher: | UKM, Bangi |
| Appears in Collections: | Faculty of Science and Technology / Fakulti Sains dan Teknologi |
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|---|---|---|---|---|
| ukmvital_84631+SOURCE1+SOURCE1.0.PDF Restricted Access | 229.95 kB | Adobe PDF |  View/Open |
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