Abstract

Identification of antibiotic residues in meat and eggs of laying hens in Togo and the ban in 2006 on using antibiotics growth promoter (AGP) in animal production by the World Health Organization induce the use of medicinal plants with antimicrobial effects, such as AGP alternatives in poultry production. For the same purpose, this study was conducted to contribute to studies using phytobiotics as alternatives to AGP in poultry production. Indeed, antibiotics have been substituted by Eucalyptus globulus leaf powder (ELP) during the starter phase. Polyphenolic compounds from ELP were determined, and the effects of different rates of ELP supplementation on growth performance, mortality, and hematological and biochemical parameters were evaluated. A total of 460 one-day-old laying chicks (Isa brown) were randomly allocated to 5 groups, each consisting of 4 replications, with 23 chicks in each replication. Treatments consisted of the basal diet (BD) without ELP and antibiotics, a negative control (group EGO-), BD with antibiotics and no ELP, a positive control (group EGO+), BD + 0.25 of ELP without antibiotic (group EG1), BD with 0.50 of ELP without antibiotic (group EG2), and BD with 1 ELP without antibiotic (group EG3). The rates of 0.25, 0.5, and 1 mean 0.25 kg, 0.5 kg, and 1 kg of ELP for 100 kg of BD, respectively. The study revealed that ELP contains flavonoids (4.85 μg QE/mg), tannins (30.34 μg CE/mg), and total phenols (165.2 μg AGE/mg). Supplementation did not affect feed intake (FI), body weight gain (BWG), feed conversion ratio, and mortality of Isa brown laying hens during the starter phase (8 weeks) in all treatment groups. However, the chicks that received ELP had the best FI and BWG, which was not significantly different from the control groups. The biochemical parameters such as total proteins, albumin, triglyceride, total cholesterol, and glycemia were not affected by ELP supplementation. Among the hematology parameters, the leukocyte decreased in the groups fed with ELP, while mortality was unaffected. The results of the present study indicated that ELP inclusion rate of 0.25 could serve as the best antibiotic replacement for Isa brown laying hens during the starter phase. © The Author(s) 2023