The effects of diets on reproductive performance of eyestalk ablated and intact mud crab Scylla serrata
MetadataShow full item record
Cited times in Scopus
The reproductive performance of female mud crabs was evaluated as affected by various diets. Dietary treatments were as follows: D1 — natural diet (mussel meat, squid, trash fish); D2 — combination of natural and formulated diets; D3 — formulated diet. Pond-sourced broodstock, with initial body weight of 300–400 g, were tagged in their carapace then stocked in three units of 10 m3 broodstock tanks at eight females per tank. Half of the females were ablated and the other half were intact. Spawnings were monitored and berried females were transferred to individual 500-l tanks for incubation of eggs. Four experimental runs were conducted. Broodstock response in terms of number of spawnings, spawnings with hatching, fecundity, egg fertilization rate, total zoea produced and broodstock survival was enhanced in females fed the mixed diet (D2) compared to those fed the natural diet (D1) or the formulated diet (D3). Larval quality measured as larval stage index followed the same trend. Results further showed that intact females fed diets D1 and D2 gave higher numerical values in reproductive performance and zoea growth index than ablated females while ablated females fed diet D3 performed better than their intact counterparts. This may be attributed to presence of essential nutrients and vitamins A, C, E in the formulated diet. Latent period from gonadal maturation to first spawning was shortened by eyestalk ablation. Use of a combined diet would ensure the production of good quality eggs and large numbers of zoea with the best chance of completing the larval stages and thus, would serve as an appropriate starting point in establishing a viable mud crab aquaculture.
CitationMillamena, O. M., & Quinitio, E. (2000). The effects of diets on reproductive performance of eyestalk ablated and intact mud crab Scylla serrata.
This project was a collaborative research between the Australian Center for International Agricultural Research ( ACIAR) and the Aquaculture Department of the Southeast Asian Fisheries Development Center (SEAFDEC) under ACIAR Project No. 9217. The authors acknowledge with gratitude the efforts of Mr. David Mann of Bribie Is. Aquaculture Research Center in Brisbane, Australia for showing us the broodstock management techniques; the assistance of Josette Bangcaya, Danilo Javellana and Cezar Tabigo-on in the conduct of the experiments; Mr. Roman Sanares, in the statistical analysis of data; the Centralized Analytical Laboratory staff, in proximate and water analyses; and the Feed Mill laboratory staff, in broodstock diet preparation; both of the SEAFDEC Aquaculture Department.
Showing items related by title, author, creator and subject.
Evaluation of dietary freeze-dried Chaetoceros calcitrans supplementation to control Vibrio harveyi infection on Penaeus monodon juvenile Effects of supplementation of diets with freeze-dried Chaetoceros calcitrans to control Vibrio harveyi infection are evaluated through immune responses, and disease resistance of juvenile Penaeus monodon. Total lipid and fatty acid profile of Chaetoceros calcitrans is also analyzed. A challenge infection with 107 cfu/mL concentration of Vibrio harveyi is intramuscularly injected to juvenile Penaeus monodon after 45 days of feeding of diets supplemented with 15 g/kg and 30 g/kg dried Chaetoceros calcitrans. The use of dried Chaetoceros calcitrans is compared with that of ß-1,3 glucan Curdlan, a commercial immune enhancer. Incorporation of 30 g/kg Chaetoceros calcitrans in the diet enhances the immune system of shrimp as effected by high prophenoloxidase activity and plasma protein concentration and is better compared to the commercially available Curdlan. Chaetoceros calcitrans also contains polyunsaturated fatty acids (PUFAs) such as linolenic acid and eicosapentanoic acid (EPA) which are responsible for its antibacterial action against Vibrio harveyi. All these biological activities of Chaetoceros calcitrans add up to increase resistance of the juvenile Penaeus monodon to vibriosis as shown by its high survival rate from the challenge infection with Vibrio harveyi. Therefore, it is worthwhile to use Chaetoceros calcitrans as supplementary feed. Its effect in increasing the immune competence coupled with its antibacterial action, make the shrimp resistant to luminous vibriosis that continues to affect the industry, thereby augmenting aquaculture production.
Apparent digestibility coefficient of nutrients from shrimp, mussel, diatom and seaweed by juvenile Holothuria scabra Jaeger The ability of Holothuria scabra to digest nutrients, such as organic matter (OM), protein and carbohydrate from animal and plant feed ingredients was investigated. Four test feeds prepared by mixing sand with single ingredients from animal sources (shrimp and mussel) and plant sources (diatom and seaweed) were fed to H. scabra to estimate apparent digestibility coefficient (ADC). The total assimilated nutrient (TAN) increased with ADC, whereas ingestion rate (IR) varied slightly among the feeds suggesting that ADC might be a good indicator of nutrient availability to H. scabra. The ADCOM of shrimp and mussel was significantly higher than that diatom and seaweed: 86.2%, 77.1%, 55.1% and 32.3% respectively. ADCprotein was similar for shrimp (88.7%), mussel (84.8%) and diatom (75.2%), but significantly lower in seaweed (34.4%). ADCcarbohydrate was similar in mussel (58.5%) and diatom (58.3%) as well as in seaweed (31.6) and shrimp (28.0%). ADCprotein was relatively higher than ADCcarbohydrate suggesting that H. scabra generally digests more protein than carbohydrate. Furthermore, results indicated that nutrients from animal-based feeds are more efficiently digested by H. scabra; thus, animal ingredients rich in easily digestible protein could potentially provide an efficiently balanced diet for H. scabra fed with diatom containing high easily digestible carbohydrate.
Effect of feeding regimes on growth and survival of bighead carp (Aristichthys nobilis Richardson) fry CB Santiago & OS Reyes - In SS De Silva (Ed.), Fish Nutrition Research in Asia. Proceedings of the Third Asian Fish Nutrition Network Meeting, 1989 - Asian Fisheries SocietyTwo five-week feeding trials were undertaken to evaluate growth and survival of bighead carp (Aristichthys nobilis ) fry of 1.9-2.4 mg mean weight reared on various feeding regimes. In Treatment 1, the carp fry were fed with Brachionus alone. In Treatment 2, 3, 4 and 5, the fry were fed with Brachionus for 2, 4, 6 and 10 days, respectively, and then with an artificial diet for the remaining period. The carp fry were fed with the combination of Brachionus and artificial diet in Treatment 6 and with artificial diet alone in Treatment 7. Results showed that the combination of Brachionus and artificial diet was the best feeding regime in enhancing the growth of the bighead carp fry. Mean weights of the fry fed with Brachionus for 2, 4, 6 and 10 days prior to the shifting to artificial diet were similar to that of the fry fed with Brachionus alone or artificial diet alone. There was no distinct trend in survival as a function of feeding regime. However, Brachionus alone gave the highest survival rate in both trials.