The BROODSTOCK Table

Control of the reproductive cycle

Although several species can be reared on the basis of eggs and larvae collected from the wild (e.g., milkfish or eels), large-scale production of fry needs a broodstock of captive spawners for reliable production of eggs. The ability to control the reproductive cycle of species under cultivation is thus most important. Such knowledge ensures that hatcheries are able to maximize their production of eggs and fry and thus can tailor their production to the needs of the farms which grow fish up to table size.

The BROODSTOCK table gives basic information on biotic and abiotic conditions for proper broodstock management.

Fields

The first Broodstock field gives a classification of major triggers to induce breeding, while the second Broodstock field indicates the preferred method of gamete release.

The field Spawning behavior complements the broodstock fields and gives a more detailed description of the spawning behavior, e.g., necessary environmental factors such as the presence of spawning substrate or water flow and technical descriptions on how to obtain gametes.

The Countries/Regions field indicates the major countries where the species is known to be farmed on a commercial scale.

Stocking rate and Sex ratio present recommended values for the incubation of the broodstock for best results in obtaining gametes. If ranges are given in the literature, a mean value is calculated. The fields Male and Female may indicate typical broodstock numbers.

The field Mortality gives an indication of typical post spawning mortality.

The field Main water source indicates the usually used water source; an alternative source is mentioned in the field Supplemental water source.

The fields Temperature, Spawning Temperature, Salinity, pH, Oxygen and Hardness present the range of optimal abiotic values for the holding of the broodstock during maturation. Because temperature often has a major impact on spawning behavior, an optimal spawning temperature may be mentioned.

The free text field Comments may be used for further relevant notes about conditions of broodstock holding, nutritional status and spawning.