Информационная система ресурсов кормов и удобрений для аквакультуры

Nile tilapia - Feeding methods

In general, the feeding method used for tilapia farming depends on the culture system used, the size of the farm/ponds and the availability and cost of manual labour. In most tilapia farms where pelleted dry or moist feeds are used (either farm-made or commercial feeds), broadcasting by hand is the preferred method of feeding. Being active swimmers, tilapia will readily swim to the edge of the pond or cage where the feed is being broadcasted. Broadcasting is also the recommended method since this allows the farmer to monitor the feeding behaviour and general health of the fish, especially when extruded floating pellets are used. However, in very large ponds, a truck may be used to tow a feeder that blows pelleted feeds over a wider area of the pond to ensure even feed distribution (Figure 13).

Nevertheless, in some cases where the supplementary feeds are in powder form or other physical forms that does not allow broadcasting to be carried out effectively, feeding trays, bags or baskets can be placed in the water to contain these raw materials for the tilapia to consume. In cage culture, feeding rings are required if floating pellets are used, and feeding trays may be necessary with sinking pellets to avoid the feed being swept away.

Intensive culture systems are common in countries where the labor cost is high. Various semi-automatic systems are therefore used to reduce this cost, and increase the growth rate and to reduce the FCR:

Clockwork-driven belt feeders permit a constant distribution of feed in small quantities over a 12 hours period and are very effective for rearing of fry and fingerlings. Vibratory feeders permit to control feeding rates and times but require power supply.
Pendulum demand feeders are commonly used for ongrowing tilapia in cages, raceways and ponds. They are relatively inexpensive and do not require electrical power. This kind of device still requires feed allowance monitoring and computing, and may be used together with hand broadcasting. Any dry pellet can be used but extruded floating pellets are recommended because they reduce the risk of clogging the feeder through the disintegration of pellets from water splashing.
Electrical systems such as scatter feeders can spread pellets over the pond surface and allow for strict control of feeding rates.

In super-intensive systems, computer controlled automatic feeders are used (Figure 14). A distribution network is installed throughout the fish farm and the feed is send from the silos to the fish with an air-compressor. No handling is required and the feeding rates and frequencies are managed from a computer. This equipment is often used in closed recirculating fish farms where feeding may be accurately adjusted with the supply of oxygen to the system. The use of demand feeder (Figure 15) can complement manual hand feeding of the fish. Automatic feeders can also be set to dispense larval feeds continuously to allow tilapia fry access to feeds through out the day (Figure16). Feeding hours should also be constant in order to adjust the fish behavior.