Weaning diet trial surprises tilapia hatchery

When Dutch tilapia hatchery Til-Aqua International compared several starter diets for ten-day old male larvae it was surprised to see two proprietary feeds outperform its own optimised blend. The top performer was Gemma Wean from Skretting, which has now been adopted by Til-Aqua as its first feed, reports www.megafishnet.com with reference to Skretting.
Eric Bink, Director of Til-Aqua says, "We developed a blend of high quality larval feeds with the optimum protein and energy levels for our all-male tilapia larvae with our conviction that ‘good feeding now gives better performance later'. In mid 2010 we ran a three week trial comparing our blend with commercial alternatives. Two diets outperformed our blend with faster growth and no mortalities. Both were from Skretting but the results with Gemma Wean really amazed us. These larvae stood out from the others through their active swimming and intense colour. Additionally the faeces were fixed and solid, contributing to good water quality."

Til-Aqua, located in Velden in the Netherlands, specialises in the production and supply of Natural Male Tilapia (NMTTM) fry and tilapia broodstock based on YY-technology, backed by technical support and a hatchery design service. "Male tilapia grow faster than females," explains Bink. "At 300 days the males have almost twice the body weight of the females and get there with a significantly lower feed conversion ratio." Til-Aqua provides NMT fry and NMT-producing brood stock to tilapia producers using recirculation systems, cages or ponds worldwide.

Gemma Wean is cold extruded at Skretting's specialist plant in Vervins, France, retaining the nutritional value of the ingredients. Micro-cutting equipment ensures consistent pellets and minimises dust. The feed is produced to flow freely in automated feeders and spread readily on the surface of the water. Since the launch of the upgraded version in September 2009, Gemma Wean has become established as a weaning feed in marine hatcheries producing species such as sea bass, sea bream, meagre and turbot.