Are you looking for ways to increase the productivity and health of your Nile tilapia fish farm? Optimizing fish health and growth in aquaculture systems is essential for sustainable practices, but most importantly, to ensure the profitability of tilapia farming.
Researchers from the Universidad Autónoma Chapingo (Mexico) and the National Institute of Forestry, Agricultural, and Livestock Research evaluated the effects of dietary supplementation with essential oils (EO) on growth performance, serum antioxidant status, intestinal morphology, and overall body composition of Nile tilapia (Oreochromis niloticus) through a meta-analytic approach.
What are essential oils and how can they benefit tilapia?
Essential oils (EO) are derived from aromatic plants and are complex mixtures that promise a natural alternative to antibiotics. They contain various compounds such as terpenes and phenols, known for their antimicrobial, antioxidant, and immune-stimulating properties. The main benefits of using essential oils include:
- Antimicrobial properties to combat diseases
- Antioxidant effects to protect cells from damage
- Immune system stimulation to improve health
- Antiviral and anti-inflammatory properties for overall well-being
Studies suggest that including EO in Nile tilapia diets could offer several advantages:
- Better growth performance: Research indicates that moderate doses of EO (500-2000 mg/kg of feed) can lead to better growth rates in tilapia.
- Improved intestinal health: EOs can enhance intestinal morphology, potentially promoting better nutrient absorption.
- Stronger antioxidant defenses: Studies suggest that EOs can elevate antioxidant activity in the blood serum of tilapia, helping them combat stress and diseases.
- Leaner fish with higher protein content: EOs might decrease fat content and increase protein content in tilapia, resulting in a healthier and potentially more valuable product.
While existing research is promising, results can be contradictory. Some report improvements in growth performance, intestinal health, and antioxidant status, while others show no significant impact. These discrepancies highlight the need for a more robust data analysis approach.
Key findings
The researchers conducted a comprehensive analysis (meta-analysis) examining 45 scientific studies on the effects of EO on tilapia. The results are promising for fish farmers:
- Better growth performance: Fish fed diets containing EO significantly improved weight gain, final body weight, and overall growth rate. They also consumed more feed and showed a better feed conversion ratio, meaning less feed is wasted per unit of weight gained. This translates to higher fish yields and potentially reduced production costs.
- Enhanced antioxidant status: EOs appear to bolster the fish’s natural antioxidant defenses. Blood analyses revealed reduced levels of malondialdehyde, a marker of oxidative stress, and increased activity of antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase. These findings suggest that EOs can help tilapia cope with environmental stressors, promoting overall health and potentially reducing disease susceptibility.
- Healthier intestinal morphology: The study delved deeper into the intestinal health of the fish. EOs significantly increased the height, width, and number of finger-like projections (villi) in the intestine. These villi are crucial for nutrient absorption. Additionally, EOs increased the presence of goblet cells, which secrete mucus to protect the intestinal lining. This improved intestinal structure likely contributes to better nutrient absorption and potentially stronger gut health.
- Favorable body composition: EOs appear to influence the body composition of the fish positively. Fish fed diets supplemented with EO had elevated protein levels and reduced fat content. This results in a healthier fish product, potentially attractive to consumers looking for leaner protein sources.
Conclusion
Overall, this research suggests that dietary supplementation with essential oils holds great promise for the aquaculture industry. EOs can potentially improve the growth performance, antioxidant status, intestinal health, and body composition of tilapia.
The researchers conclude that “Within growth performance, the best results in final weight, body weight gain, and specific growth rate are obtained with essential oils containing limonene, carvacrol, or menthol as the main bioactive metabolite.”
However, the researchers caution that more research is needed to explore the optimal types and doses of EO for different species of tilapia and farming conditions.
Contact
José Felipe Orzuna-Orzuna
Departamento de Zootecnia, Universidad Autónoma Chapingo
Chapingo C.P. 56230, State of Mexico, Mexico
Email: jforzuna@gmail.com
Reference (open access)
Orzuna-Orzuna, J. F., & Granados-Rivera, L. D. (2024). Growth performance, antioxidant status, intestinal morphology, and body composition of Nile tilapia (Oreochromis niloticus) supplemented with essential oils: A meta-analysis. Research in Veterinary Science, 176, 105353. https://doi.org/10.1016/j.rvsc.2024.105353
