Page 21 - AWA Vol.41-No.8

FISHERIES AND FISH FARMING

ids, and other nutrients.
Moist diets, developed in the 1980s
and composed of fishmeal and other
marine meals (mainly krill and squid),
oils, nutritional additives, and fresh in-
gredients, are commonly used. Many
hatcheries still produce these moist di-
ets in-house.
While the precise nutritional require-
ments of broodstock fish, shrimp, and
other crustaceans are not fully under- moist diet preparing sardins for broodstock
stood - particularly for newly cultured
species such as groupers (Epinephelus taining extracts of Withania somnifera, Mucuna pruriens,
sp.), Seriola sp., cobia, lobsters, and crabs - these require- Ferula asafoetida, and Piper longum have led to signifi-
ments are often partially or fully met through supplemen- cant increases in fecundity and gonadal weight, as well as
tation with fresh feeds and nutritional boosters. shorter inter-moult periods. Similar improvements were
Current commercial broodstock diets and supplements observed when these herbal extracts were delivered via
primarily target the nutritional needs of fish and shrimp. bioencapsulated Artemia.
However, additives that directly support the hormonal Many plant-derived compounds also exhibit non-specif-
cycle, and thereby enhance gonadal development and ic immune-stimulating effects in animals, with more than
fecundity, remain scarce. This is especially true for out-of- a dozen evaluated in fish and shrimp. Herbal compounds
season broodstock groups of both established and emerg- can inhibit the generation of oxygen anions and scavenge
ing aquaculture species. free radicals, thereby mitigating stress. For example,
Moreover, other important factors that influence brood- Picrorhiza kurroa extract has demonstrated anti-stress
stock performance - such as stress, immune function, and properties in P. monodon. Other herbs, such as Astraga-
digestive efficiency - are seldom directly addressed in lus membranaceus, Portulaca oleracea, Flavescent opho-
diet formulations. ra, and Andrographis paniculata, are known for their
stress-reducing and immune-enhancing effects.
Herbal medicine has long been used in human health for
managing reproductive and hormonal issues, yet its adap- Currently, several fish and shrimp hatcheries worldwide
tation in aquaculture remains limited. Medicinal plants are are incorporating commercially available herbal extract
known to have hormone-modulating properties, and cer- blends designed to modulate hormonal activity and im-
tain herbs are used in human medicine as natural boosters prove reproductive performance. These are particularly
of hormonal cycles in both men and women, including in used for out-of-season broodstock and species with re-
hormone replacement therapies. productive challenges, such as groupers (notably with
The effects of herbal extracts on the development and low sperm motility and volume).
performance of fish and shrimp broodstock have not For instance, the inclusion of a commercial herbal ex-
been thoroughly investigated (Kolkovski, 2011). Howev- tract mix in the diet of Seriola lalandi broodstock yielded
er, scientific evidence suggests that, beyond their known similar spawning performance during both the regular
antibacterial, antiviral, and antifungal properties, plant and off-season (Kolkovski, 2021; Kolkovski & La Camera,
extracts can significantly enhance vitellogenesis and 2015).
spermatogenesis. This results in improved egg quality, However, the use of herbal extracts in aquaculture in
sperm motility and viability, higher fecundity, greater Western countries (e.g., the EU and the USA) is subject
hatching success, and superior larval quality. to strict and comprehensive regulations. In many cases,
In black tiger shrimp (Penaeus monodon), diets con- herbal extracts are classified as medications, requiring
extensive and costly approval processes. Consequently,
the use of herbal extracts as feed additives for broodstock
- and indeed in aquaculture in general - remains very lim-
ited.
Conclusion
Although substantial information is available on the nutri-
tional requirements of marine fish and shrimp broodstock,
optimal feeding regimes have yet to be fully established,
especially for new and developing aquaculture species.
Greater emphasis should be placed on reducing reliance
on live, fresh, and frozen seafood in broodstock diets.
Herbal extracts and phytotherapeutic compounds offer
a promising avenue for improving broodstock condition
through both direct and indirect physiological effects. Fur-
ther research is needed to integrate these bioactive com-
moist diet preparation – chile Feeding barramundi broodstock with pounds into modern aquaculture nutrition strategies.
maturation diet
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Vol. 41 No. 8 19