By Development Communication Section
Over a hundred fish farmers and other stakeholders availed
of free lectures and consultations on 11 July 2018 at SEAFDEC/AQD’S Multi-Purpose
Hall in Tigbauan, Iloilo as part of the annual Farmers’ Forum and Aquaculture
providing the public with aquaculture updates, SEAFDEC/AQD specialists shared
developments on aquaculture feeds made from locally available ingredients,
giant freshwater prawn farming, shrimp farming, and tilapia breeding and
In the aquaculture clinic that followed the lectures, stakeholders
also had the opportunity to consult various SEAFDEC/AQD specialists regarding
their specific concerns including problems in farming and opportunities for
The activities were organized as part of the events
commemorating SEAFDEC/AQD’s 45th founding anniversary.
Cost-effective aquaculture feeds made from locally available
To promote the use of cost-effective aquaculture feeds, SEAFDEC/AQD
feed nutrition scientist Dr. Roger Edward Mamauag shared different alternative protein
sources for fish feeds. Protein is usually sourced from fish meal but feeding captured
fish to farmed fish is considered an unsustainable practice.
Dr. Mamauag revealed that processed meal from knife fish can
replace the common fishmeal ingredient up to a 43% inclusion level in juvenile
tilapia diets. Knife fish is considered as a pest in Laguna de Bay, the largest
lake in the Philippines.
Protein-enhanced copra meal was also found to be able to
replace fishmeal by up to 40% as ingredient in shrimp diets. In milkfish diets,
the fermented copra meal can be added up to 25% inclusion level, partially
replacing soybean meal. Copra meal is a byproduct in the production of coconut
The use of some plant-protein sources, including
agricultural wastes, in tilapia diets was reported to also contribute to improved
One such agricultural waste is mango peel silage which contains
39.72-42.38% crude protein and is heavily concentrated with carotenoids which
are important for fish reproduction.
Soybean curd was also tested to successfully replace up to 45%
of fish meal in aquafeeds. Citrus peel and citrus pulp on the other hand, can
be added for up to 50% and 10%, respectively.
Aside from reducing the use of fish oil and fish meal, Dr.
Mamauag stressed the importance of ensuring the efficient conversion of
nutrient inputs and the use of technologies that are environmentally sensible and
Giant freshwater prawn farming
Giant freshwater prawn, Macrobrachium
rosenbergii, is gaining popularity as an aquaculture species as reflected
in the increase in worldwide production from about 30,000 tons in 1990 to about
200,000 tons in 2010.
In her presentation, SEAFDEC/AQD scientist Dr. Maria Lourdes
Aralar narrated the culture protocols in the culture of the prawn from broodstock
management, hatchery design, requirements for larval rearing, water management,
feeding schedule, nursery system, and the different grow-out systems.
One of the tips mentioned by Dr. Aralar in grow-out culture
is to size-grade the postlarvae before stocking. Size grading results in more
uniform growth and reduces percentage of small-sized prawns at harvest.
In feeding, Dr. Aralar suggested to use feeding trays to
monitor feed consumption and to reduce feeding rate by 50% if oxygen fall below
3.5 ppm in early morning and temperature falls to 20-24 degrees Celsius during
Dr. Aralar also presented sample growth parameters in
lake-based culture using batch system with a stocking density of 10-15 pieces
per square meter. With a culture duration of five months, daily growth rate is
0.17-0.22 gram per day leading to an average weight at harvest of 25-35 grams
and a feed conversion ratio of 1.8-2.2.
With SEAFDEC/AQD’s current thrust on reviving the tiger
shrimp industry or “Oplan Balik Sugpo,” shrimp pond culture expert Mr. Victor
Emmanuel Estilo presented different strategies to avoid disease occurrences.
Mr. Estilo listed the basic facilities required to ensure
biosecurity in shrimp farms such as hand wash/foot bath stations, tire baths
stations, bird scare devices, water filters and crab fences.
Other proactive strategies to avoid diseases include the use
of high health, specific-pathogen-free postlarvae, probiotics, minimum to zero
water exchange systems, and the conduct of regular disease surveillance and
Also recommended were the use of reservoirs or underground
water sources, HDPE-lined ponds, automatic feeders, sludge removal facilities
and smaller pond compartments.
Farmers should focus on “animal comfort,” said Mr. Estilo, and
time culture periods with seasons of higher average temperatures and less rain,
to keep shrimp robust and minimize the occurrence of diseases.
Tilapia breeding and farming
Dr. Maria Rowena Eguia, a scientist at SEAFDEC/AQD, revealed
that four out of the top ten tilapia-producing countries in the world are from
Southeast Asia, namely Indonesia, Philippines, Viet Nam and Thailand where it
is a popular aquaculture species since it breeds easily, grows fast and adapts
to a wide range of environmental conditions.
Dr. Eguia added that tilapia involves a simple hatchery and
nursery technology, enjoys wide consumer acceptance, and is used as a
bio-control agent for luminous bacteria in shrimp ponds in the Philippines.
After sharing the basics of tilapia culture, Dr. Eguia also mentioned
the use of netting materials called “Aquashade” which can reduce pond heat by
40% and double the spawning rate and seed production of a tilapia farm during
extremely warm summer months.
Dr. Eguia also outlined the research work being done by
SEAFDEC/AQD for tilapia such as the genetic improvement of performance traits,
DNA marker assessment of improved strains, and marker-aided broodstock