Modulation of growth performance, gut morphometry, and cecal microbiota in broilers by clove ( Syzygium aromaticum) and tulsi ( Ocimum sanctum) supplementation

Abstract

In an epoch of the growing risk of antibiotic resistance, there is a dire need to establish an effective novel feeding practice for broiler nutrition as an alternative to antibiotics. Hence, the aim of the current study was to evaluate the impact of clove powder and tulsi extract on the growth performance, gut morphologic and morphometric indices, and cecal microbial status of broiler, as an alternative to antibiotic growth promoters ( AGPs). Sixty day-old chicks of Cobb-500 strain were randomly divided into 4 groups, each having 15 birds. Chicks of the control group (T0) were fed commercial broiler feed with no additional supplementation. The treatment groups were offered commercial broiler feed and received clove powder and tulsi extract with drinking water at the rate of 0.5% + 2% (T1), 1% + 3% (T2), and 1.5% + 4% (T3), respectively. Results showed a nonlinear relationship with the dosage of clove and tulsi. All the growth parameters substantially ( P < 0.05) improved in T2 while T1 and T3 showed no significant improvement compared to T0. The final body weight was significantly ( P < 0.05) higher in T2. Giblet and offal weights showed no noticeable differences except in the intestine and heart where intestine weight markedly ( P < 0.05) decreased in T3 and heart weight significantly ( P < 0.05) increased in T1 and T2. Clove and tulsi supplementation substantially improved the villus height and villus surface area of the small intestine in T2 while the large intestine remained mostly unaffected by the treatment. Cecal microbial status significantly improved in all the treatment groups having increased ( P < 0.05) Lactobacillus spp. count and decreased ( P < 0.05) E. coli count compared to T0. Based on the aforementioned findings, it can be concluded that the combination of clove and tulsi can improve the growth performance and gut health of broilers which is largely dose-dependent and might be supplied as a potential alternative to AGPs.