General considerations
Index
- Production of Nile tilapia
- Tilapia feeding: nutritional requirements
- Main ingredients and factors to consider
- Facilities of Delta Labs Lab
1. Production of Nile tilapia
The term tilapia includes fish of the cichlid family native to Africa and the Middle East. Its production in aqua facilities is widespread in some areas of the planet; in fact, it is the third most cultivated fish after salmon and carp. Its preference for warm temperatures means that the main producers are located in warm or tropical zones, specifically in some areas of China, in Southeast Asia, Central America and some African countries.
They reach commercial size, between 600 and 900 grams, in about 6-9 months and the most cultivated species are the Nile tilapia (Oreochromis niloticus), the blue tilapia (O. aureus) and Mozambique tilapia (O. mossambicus), plus some hybrids.
This species has multiple features that make it ideal for aquaculture farms, such as its rapid growth, a relatively high resistance to diseases, tolerance to different salinities (euryhaline fish) and tolerance to high densities. Regarding feeding, tilapia adapts easily to commercial diets as long as they are formulated according to the needs of the species.
2. Tilapia feeding: nutritional requirements
Tilapias are mainly herbivores, but are considered omnivores because they require high-protein diets, particularly in the juvenile stages, and can growth easily when fed with different commercial diets.
Extruded feed is usually administered in the form of pellets, preferably floating in order to be able to monitor the consumption and the amount of feed left in the pond or in the facilities where tilapias are raised.
> Protein:energy ratio and amount of feed
Generally speaking, the protein:energy ratio is usually higher in the early ages and decreases as the fish grows. Thus, in tilapia fry, the ideal ratio is 123 mg of protein/kcal; while, in juveniles, the ideal ratio is 108 [1]. In fact, high energy levels also have a negative impact on the quality of the product, as they will lead to fat accumulation in the carcass [2].
Another parameter that also decreases as tilapias develop is the ratio feed:fish average weight.
| Development stage | Protein (%) | Digestible energy (kcal/kg) | Protein:energy ratio (mg prot./kcal) |
| Fry (2.5 g) | 56 | 4600 | 123 |
| Juveniles (7.5 g) | 34 | 3200 | 108 |
> Protein and other nutrient requirements
Protein is nutrient of greater importance and with a great impact on the growth rate. The protein content of the diet in early stages of development accounts ofr up to 50% of the feed composition and decreases as tilapia grows. These percentage is achieved with highly protein ingredients, either of animal origin, like fish or meat meals, or of vegetable origin, like soybean meal.
| Protein requirements according to developmental status and weight | |
| Larvae | 45-50% |
| Fry and fingerlings(0.02-10 g) | 35-40% or higher |
| Juveniles (10 – 25 g) | 30-35% |
| >25 g | 28-30% |
| >50 g | 20-25% |
| >150 g | 32-35% |
| >250 g | 27-29% |
| >300 g | 35% |
Other nutrients to consider are fat, which should account for 4 to 6%, and phosphorus,which should be between 0.54% and 1.14%. When using vegetal ingredients, the diet is usually supplemented with phosphorus and phytase, since the phytic acid present in these ingredients binds to phosphorus and other metal ions, elements that are no longer available to the animal.
Tilapias can use around 40% of all the carbohydrates in the die. Despite this fact, since carbohydrate inclusion decreases feed cost, they usually make up between 30% and 70% of the feed.
| Amino acid requirements (NRC,2011) expressed as % of protein | |
| Lysine | 5.0-5.7 |
| Methionine | 2.2-3.1 |
| Methionine+Cysteine | 2.3-4.0 |
| Threonine | 2.0-3.9 |
| Tryptophan | 0.5-1.0 |
| Phenylalanine+Tyrosine | 5.0-6.5 |
| Arginine | 4.2-6.0 |
| Histidine | 1.5-2.1 |
| Isoleucine | 2.2-3.1 |
| Leucine | 3.3-4.1 |
| Valine | 2.8-3.6 |
3. Main ingredients and factors to consider
The basis of tilapia diets are protein ingredients,which can come from animals or plants. Within the first group, fish meal and MBM are among the most used. They contain a very high percentage of high-quality and highly available protein, but they tend to have higher prices and are not sustainable resources [3].
On the other hand, the most commonly used protein ingredients of plant origin are soybean, cotton or rapeseed meal. Keep in mind that these ingredients, despite being more affordable and sustainable, usually contain anti-nutritional factors (FANs) [4], such as antitrypsin that impairs protein utilization
If very high amounts of plant-based ingredients are included, the diet should be supplemented with enzymes capable of inactivating FANs that help to digest the protein in the formula.
4. Delta Labs Lab Services
From Delta Labs Lab we offer the service of analysis and formulation of diets for animals, which allows to optimize the composition of the feed contemplating the inclusion of the best functional additives. To use this service, you can contact us through our website www.globalvetslab.com or by email to the address info@globalvetslab.com.
Sources consulted
- [1] R. R. S. Robert A. Winfree, “Effects of Dietary Protein and Energy on Growth, Feed Conversion Efficiency and Body Composition of Tilapia aurea,” J. Nutr. , vol. 111, no. 6, pp. 1001–10012, 1981.
- [2] F. Hanley, “Effects of feeding supplementary diets containing varying levels of lipid on growth, food conversion, and body composition of Nile tilapia, Oreochromis niloticus (L.),” Aquaculture,vol. 93, no. 4, pp. 323–334, 1991.
- [3] GVL, “Alternative sources of protein in breeding of carnivorous fish. Use of enzymes.,” Delta Labs Lab,2021. [Online]. Available: https://www.globalvetslab.com/fuentes-alternativas-de-proteina-en-cria-de-peces-carnivoros-uso-de-enzimas/.
- [4] G.B. Mbahinzireki, K. Dabrowski, K.-J. Lee, D. El-Saidy, and E. R. Wisner, “Growth, feed utilization and body composition of tilapia (Oreochromis sp.) fed with cottonseed meal-based diets in a recirculating system,” Aquac. Nutr. , vol. 7, pp. 189–200, 2001.