Thyroid hormone surges during milkfish metamorphosis
View/
Date
1994Page views
3,671ASFA keyword
AGROVOC keyword
Taxonomic term
Metadata
Show full item recordShare
Abstract
Both thyroxine (T4) and triiodothyronine (T3) were detected in fertilized eggs and larvae of milkfish. The concentration of T4 was lower than that of T3 only in fertilized eggs and newly-hatched larvae. The total body concentrations of both thyroid hormones decreased after hatching. The T4 concentration fluctuated at relatively low levels during the first week after hatching, increased gradually during the next 2 weeks and was highest in 4-week-old larvae. On the other hand, T3 was undetectable in samples taken between days 3 and 11, showed a gradual increase beginning on day 13 and was highest in 27 day old larvae. The concentrations of both T4 and T3 declined again in 31-day-old juveniles. The peak corresponds with the development of silver coloration in hatchery-reared milkfish and the inshore milkfish and the inshore migration of larvae in the wild, suggesting a role for thyroid hormones during early development of this species.
Suggested Citation
de Jesus, E. G. (1994). Thyroid hormone surges during milkfish metamorphosis. The Israeli Journal of Aquaculture-Bamidgeh , 46(2), 59-63. http://hdl.handle.net/10862/1449
Type
ArticleISSN
0792-156XCollections
- Journal Articles [1266]
Related items
Showing items related by title, author, creator and subject.
-
Series: Aquaculture extension manual; No. 25
The modular method: Milkfish pond culture
(Aquaculture Department, Southeast Asian Fisheries Development Center, 1999)The modular method of milkfish culture (Chanos chanos) described in the manual is an improvement over the traditional extensive method. The manual is intended for the use of fish farmers and aquaculturists, extensionists, and students of aquaculture not only in the Philippines, but also in other milkfish-producing countries in Southeast Asia and the world. It covers the following: Interesting facts about milkfish -- biological characteristics, artificial breeding of milkfish; Design and operation of modular pond system -- pond preparation, stocking in the nursery or transition ponds, stocking in the rearing ponds, care of stock, pond utilization and production schedule, harvest and post-harvest; and, Economics and costing. -
Evaluation of organic and inorganic fertilizers in brackishwater milkfish ponds
(Elsevier, 1989)The study was conducted in twelve 144-m2 ponds to evaluate the effect of different organic and inorganic fertilizers on the growth, survival, gross production, and profitability of marketable milkfish. The following treatments were used: Treatment I, SEAFDEC traditional fertilization practice (16-20-0 at 50 kg/ha and 45-0-0 at 15 kg/ha); Treatment II, half-dosage of Treatment I; Treatment III, chicken manure at 0.5 ton/ha; and Treatment IV, MASA (processed from agricultural and industrial wastes) fertilizer at 0.5 ton/ha. All treatments were applied once in every 2 weeks. No significant difference (P > 0.05) existed in the harvest and production of milkfish among the treatments. However, economic indicators such as return-on-investment (ROI), payback period, and marginal analysis ranked the performance of the fertilizer treatments in the order of I, II, III and IV. Fish kills occurred in three ponds applied with chicken manure and MASA fertilizer. This could have been due to a heavy build-up of organic matter in the pond bottom which led to the collapse of the benthic algal community, depletion of dissolved oxygen and the presence of hydrogen sulfide. It is therefore suggested that a lower dosage of organic fertilizer should be applied in ponds especially during the rainy season. -
Milkfish breeding and hatchery technology at SEAFDEC/AQD
(Aquaculture Department, Southeast Asian Fisheries Development Center, 1999)Describes the techniques already adopted by the private sector: broodstock management, broodstock diet, commercial fry production, live transport, and larval diet. A list of AQD research publications on milkfish is included.
