Open Access
Research (Published online: 23-01-2024)
23. Effects of essential oils on egg production and feed efficiency as influenced by laying hen breed: A meta-analysis
Arif Darmawan, Ergin Öztürk, Emrah Güngör, Şevket Özlü, and Anuraga Jayanegara
Veterinary World, 17(1): 197-206

Arif Darmawan: Department of Animal Nutrition and Feed Technology, Faculty of Animal Science, IPB University, Bogor, Indonesia; Department of Animal Science, Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey; Animal Feed and Nutrition Modelling Research Group, Animal Science Faculty, IPB University, Bogor, Indonesia.
Ergin Öztürk: Department of Animal Science, Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey.
Emrah Güngör: Department of Animal Science, Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey.
Şevket Özlü: Department of Animal Science, Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey.
Anuraga Jayanegara: Department of Animal Nutrition and Feed Technology, Faculty of Animal Science, IPB University, Bogor, Indonesia; Animal Feed and Nutrition Modelling Research Group, Animal Science Faculty, IPB University, Bogor, Indonesia.

doi: 10.14202/vetworld.2024.197-206

Article history: Received: 30-09-2023, Accepted: 26-12-2023, Published online: 23-01-2024

Corresponding author: Arif Darmawan

E-mail: arifdarmawan@apps.ipb.ac.id

Citation: Darmawan A, Öztürk E, Güngör E, Özlü Ş, and Jayanegara A (2024) Effects of essential oils on egg production and feed efficiency as influenced by laying hen breed: A meta-analysis, Veterinary World, 17(1): 197-206.
Abstract

Background and Aim: Successful rearing of laying hens to achieve optimal egg production is an endeavor that often faces various constraints and challenges, such as infectious diseases, environmental stressors, and fluctuations in feed quality. The incorporation of essential oils (EOs) into the diet of laying hens has attracted considerable attention in recent years. Therefore, our study aimed to evaluate the efficacy of EO inclusion in laying hen diets by considering the effects of production phase and breed on performance, egg quality, serum biochemistry, gut health, and antioxidant activity.

Materials and Methods: The articles were obtained from the Web of Science, Scopus, Science Direct, and PubMed using the search terms “essential oils,” “laying hens,” and “phytobiotics.” Data from 27 articles and 71 experiments were grouped according to laying hen production phase and breed in the database. The EO levels ranged from 0 to 1000 mg/kg, with thymol and carvacrol being the major EOs. A mixed model was used to analyze the data. Random effects were applied to the treatment, and fixed effects were applied to EO level, production phase, and breed.

Results: Egg production, feed intake, feed efficiency, eggshell quality, villus height, crypt depth, superoxide dismutase, and glutathione peroxidase levels increased linearly (p = 0.05) and egg weight and mass increased quadratically (p < 0.05) with increasing EO concentrations. An interaction was observed between the EO level egg production and feed conversion ratio (p = 0.05). Serum glucose, cholesterol, and malondialdehyde levels decreased with increasing EO concentrations (p < 0.05).

Conclusion: The inclusion of EOs effectively increased egg production, feed efficiency, egg weight, egg mass, eggshell quality, oxidative enzymes, and intestinal health. In addition, the proportion of dietary EOs in lightweight laying hens was higher than that in semi-heavy-weight laying hens in improving egg production and feeding efficiency.

Keywords: antioxidant enzyme, egg production, egg quality, gut health, serum biochemistry.