Evaluation of Extruded Feed in Laying Hens: A Meta-analysis on Performance and Egg Quality

The present study was designed to assess the impact of extruded feed on laying hens using a meta-analysis approach.The database was established based on 18 articles divided into processed and supplemented extruded feed ingredients.The information was analyzed using OpenMEE software, considering the specific studies as random and extruded feed as fixed effects.The results presented no statistically significant variance in the effects of extruded feed on hen-day production, but there was a significant variance in feed conversion ratio (FCR) and feed intake (P<0.05).Regarding egg quality, there were no alterations in albumin weight, Haugh units, or yolk weight between the processed and unprocessed feed ingredients.Egg weight and albumin height (P<0.05)increased significantly with processed extruded feed ingredients.In terms of comparison of supplementation with extruded feed, the performance of laying hens was not significantly higher with supplementation than without supplementation of extruded feed.The egg quality and egg weights of laying hens fed with the supplemented diets were significantly lower than those of hens fed with the diets without supplementation (P<0.05).There was no statistically significant variance in the effects of supplementation with extruded feed on albumen weight, Haugh unit, and yolk weight.In conclusion, the effects of processing extruded feed and supplemented extruded feed ingredients differ in performance and egg quality.