A good start is the key to success in fry production
A good start is key to achieving healthy fry throughout the production process and therefore for success in fish farming. Good water environment, high hygiene standards and optimal care are all important criteria. Also feed plays an essential role in fry production.
The feed must cover all the quickly growing fry’s needs, and must:
- contain the appropriate nutrients
- be easily digestible
- stimulate appetite for quick growth and minimum waste of feed
Physically the feed must be:
- dust free
- quickly and easily digestible
- easy to use with a minimum of waste
- available in sizes which allow fry of any size to eat
Aller Aqua, one of the world’s most experienced producers of high quality extruded fish feed for aquaculture, offers a series of products adjusted to the aforementioned requirements; Aller Aqua Hatchery PackTM.
Raw materials of the highest quality
The hatchery Pack products have been continuously developed and are characterized by a high degree of stability, where the quality of the raw materials is more important than the cost. The formulations have evolved based on demands of high and stable quality of the feed, and the fluctuating prices on raw materials do not influence this. Aller Aqua’s fry feed is based on a high content of marine raw materials, including krill meal.
Krill is a crustacean, living in the Antarctic Ocean. It is said to constitute the largest living biomass on earth and is estimated to 400 million tonnes. Due to fresh krills limited durability and the large distances in the Antarctic Ocean, krill meal is prepared on factory boats, where the freshly caught krill is taken directly from catch to processing. Meal from krill is therefore very fresh and known for its attractive taste which stimulates the appetite of farmed fish.
Krill meal contains a minimum of 56% protein and 20-30% fat, as well as approximately 130 ppm of natural astaxanthin, which besides being a colorant is also a very effective antioxidant. Approximately 15% of the fat in krill meal is the two important omega 3 fatty acids; EPA and DHA, but it is just as important that more than 40% of the fat is made up by phospholipids.
Live tissue consists of cells, enclosed by cell walls. Fry grows fast compared to their size, and thus create a lot of cells. Phospholipids are considered the building stones of cell walls and thus it is important for the development of healthy, flexible and functional cells that the fry are well supplied with phospholipids.
Sustainability is an integrated part of Aller Aqua -
Production of Hatchery Pack
The products are warm-extruded. In this process, the products are subjected to pressure cooking, which combined with mechanical processing, activate the feed’s content of starch. During the drying and cooling stages of production the starch solidifies and form a lattice structure, which is what gives the finished product it’s robust yet open structure, where both pills and granulates can be sifted to dust-free products.
The extrusion process results in increased digestibility of certain nutrients, but equally important in this connection, is that the process further leads to feed being stable in water, and thus does not dissolve until eaten. Any wasted feed will sink to the bottom of the basin and be lead away with water flow or otherwise removed.
Quality assurance is integrated into all steps of the fish feed manufacture at Aller Aqua -
Hatchery Pack – both mini pellets and granulates
Ten years ago mini pellets for fry entered the market and Aller Aqua launched ALLER FUTURA MP. The series of mini pellets included the smallest pellet on the market – just 0,2 mm. This small pellet is succeeded by four pellets covering the interval from 0,4 mm until 1,3 mm. The mini pellets were a big step in the direction of dust-free feed and quickly gained widespread recognition.
However, feeding with mini pellets can be a challenge as the more compact structure has the effect that it is difficult to use the pellets without waste, in terms of feed that sinks to the bottom of the basins quicker than the fish can eat it. Many fish farmers have thus decided to continue using granulates and the interest for granulates is currently on the rise.
Granulates are the original form of industrially processed starter feed. The production of granulates begins by producing a larger pellet. The pellets are then cut, and subsequently sifted and divided into the desired sizes.
The advantages of granulates are many, but most importantly they:
- float easily on the water surface and spread over a large area regardless of feeding technology
- sink slowly and allow the fish a natural eating pattern in all depths of the water
- have a size distribution which satisfies the natural spread in fish sizes of ungraded fry
- have an open structure, allowing the digestive fluids of the fish fast and effective access to the nutrients in the feed, which is of great importance in the fry’s short digestive system
Floating and low sinking speed
Granulates have a large surface area and a low density. It is therefore easy to get the granulates to float before they slowly sink. An effective feeding, which ensures the fry the possibility of eating all of the feed, is attainable with all the most common feeding technologies. It is unnecessary to fit feeding systems as close to the surface as possible, heightening the risk of splashing water. It is, therefore, easier to keep the feeding system dry, clean and hygienic.
All fry are able to eat
Newly hatched fry is not a homogenous group. Some fry hatch earlier than others and are thus more developed when the farmers begin to feed with fry feed. When the fry starts eating, not all of them have an equal appetite and the fry grow at different paces. Granulates consider these variations. When the original pellet is cut, a natural variation in size occurs. The subsequent sifting process divides the granulates into groups relating to the corresponding granulate sizes. The graph visualizes how the granulate sizes overlap.
The overlap can also be illustrated differently. The picture below gives an impression of the overlap in sizes. The result is that all fry, regardless of size, is able to eat and grow.
Dust is no longer a problem
Previously granulates have been known to contain an extent of fine particles/dust, which could cause a higher level of nutrients in the water, and often caused problems with infections in the gills of the fry. The picture above shows the variation in granulate size, but also the fact that there is no dust in the products.
The use of warm extrusion for the processing of granulates, combined with modern technology for sifting of the products, results in modern granulates being dust-free.
Efficient uptake of nutrients
Fry grow fast and thus need to absorb relatively large amounts of nutrients. This is why fry is often fed throughout the day or even around the clock, in an attempt at getting the fish to eat several times.
Fish, and in particular fry, have a very short digestive system and the intensive feeding regime only allows limited time for the system of the fish to absorb the nutrients from the feed. It is therefore important that the feed is both easily digestible and at the same time has a shape which allows the fry to quickly utilize it.
Opposite the more compact mini pellets the structure of the granulates is open and nutrients easily accessible. This gives the gastro-intestinal digestive fluids optimum possibility of entering the feed particle and process it via the very large surface.
Granulate surface versus pellet
Hatchery Pack – a solution for every situation
Aller Aqua has many years of experience with efficient feed for modern fish farming and we are happy to make our experience available to you. Our representatives can provide further information – also regarding solutions for non-standard conditions.
We comply with all national and European regulations for conventional fish feed manufacturing, and furthermore, we are a certified producer of organic feed -