Effect of molting programs and Humulus lupulus plant on tibia characteristics and expression of TRPV6 gene in different molting periods of laying hens

The aim of this study was to determine the effects of molting programs and Humulus (Humulus lupulus) plant on tibia characteristics and expression of TRPV6 gene in Pre, during and post-molting layers. Experiment 1, Hy-line W-36 (75-76 weeks, n= 272) laying hens 20 hens slaughtered before molting at end of 76 week for checking status. Experiment 2, A total of 252 Hy-line W-36 were managed in 7 treatments, 6 replicates and 6 birds in each. Treatments including: (A) feed withdrawal (FW), (B) basal diet + 2% Portulaca oleracea plant powder, (C) basal diet + 30% sunflower seed hulls + 2% Portulaca oleracea powder, (D) basal diet + 2% white button mushroom waste, (E) basal diet + 30% sunflower seed hulls + 2% white button mushroom waste, (F) basal diet + 30% sunflower seed hulls and (G) basal diet (Control treatment). Experiment 3, A total hens of treatments in experiment 2 after slaughter of 20 hens maintained for experiment 3, then each treatment diet was modulated in to two treatments (with and without Humulus). In this step, this 224 Hy-Line W-36 laying hens were designed by 14 treatments, 4 replicates and 4 hens in each in a 7×2 factorial arrangement with completely randomized design (CRD). The highest tibia weight and bone cortical thickness were observed in the treatment contain Portulaca Oleracea powder (p < 0.05). A higher tibia weight, bone cortical thickness, ash and density were indicated by Humulus plant in post-molting periods (p < 0.05). The bone cortical thickness and ash were increased by basal diet + 30% sunflower seed hulls + 2% Portulaca Oleracea powder and basal diet + 30% sunflower seed hulls treatments at post molting periods (p < 0.05). During the post-molting period, there was no significant effect on maximum strain and elastic modulus by Humulus and molting methods (p > 0.05). Also, no significant differences were found in expression of TRPV6 mRNA in the jejunum, kidney and egg shell gland (ESG) during molting and post-molting periods (p > 0.05). In conclude, improve tibia characteristics during molting and post-molting periods by Portulaca oleracea powder and white button mushroom waste Moreover, Humulus plant improved tibia status without affecting TRPV6 mRNA expression.