The Effect of Vitex Agnuse Castus Fruits Powder on Oviduct Markers Gene Expression of Laying Hens

Phytoestrogens are herbal estrogens with estrogen-like functions and structures. The estrogen hormone has an important role in the process of the synthesis of egg white proteins in the avian oviduct. Vitex agnus-castus (VAC) is a native plant of the middle Asian, southern European, and Mediterranean countries. This plant has numerous uses in traditional medicine and is traditionally used to treat many diseases in women. Previous studies have shown that VAC contains high levels of phytoestrogens. VAC consists of compounds such as vitexin, apigenin, and pendoltin, which are the most active phytoestrogen in VAC fruits. No study has been published so far on the effect of VAC on oviduct markers gene expression (ovalbumin (OVAL) and ovomucoid (OVM)). Hence, this study was performed to evaluate the effect of VAC fruits on gene expression for two oviduct markers OVAL and OVM of laying hens.

A total of 90 leghorns (Hy-Line, W-36) laying hens on the second cycle of production (at 72 to 80 weeks old) were used in a completely randomized design with three treatments, five replicates and six hens per replivate. The treatments were various levels of VAC fruit powder including zero, 1, and 2% levels of VAC fruit powder per kg of diet. After extraction of total RNA, RNA quality was evaluated using Nanodrop and agarose gel electrophoresis and cDNA was synthesized using a Sinaclone kit. Eventually, gene expression was measured by the real-time qPCR method. In this method, 𝜷-actin gene was used as a reference gene to normalize the gene expression data. To confirm the specificity of each primer, its melting curves were examined.

Electrophoresis of the PCR products showed the 60, 133, and 150-bp fragments for OVAL, OVM, and Beta-actin, respectively. Melting peaks analysis on the PCR products for all primers confirmed minimal primer-dimers and primer specificity. The results of the real-time qPCR method indicated that supplementation of VAC fruits powder at levels 1 and 2 to the diet of laying hens has no effect on the expression of OVAL and OVM genes of laying hens in the second production cycle.

Therefore, Adding VAC fruit powder to the diet of laying hens is not expected to increase egg production in laying hens. Therefore, VAC supplementation is not recommended to the diet of laying hens.