Differential growth performance and intestinal immune gene expression in diverse genetic lines of growing chickens fed a high concentration of supplemental phytase

Abstract

The objective of the current experiment was to determine the effects of high-concentration phytase (5000 FTU/kg) feeding to diverse lines of chickens fed phosphorus (P) adequate maize–soybean meal diets (4.5 g/kg non-phytate P) on the performance and intestinal immune function. Performance was measured for outbred broiler (Ross 308) and inbred Fayoumi lines over 0–21 days, and duodenum and ileum were harvested for the determination of mucin-2, interleukin (IL)-1β and IgA mRNA by quantitative reverse transcription polymerase chain reaction. Over the 0–7-day period, there was a significant line × diet interaction, as high phytase supplementation increased broiler average daily gain (ADG), but had no effect on Fayoumi ADG. Treatment of diets with phytase increased expression of the mucin-2 gene in the duodenum mucosa. There were significant interactions between line and age, and line, diet and age on duodenal expression of the IL-1β gene as phytase supplementation of the broiler line reduced IL-1β in comparison to control fed broilers without change in the Fayoumi line. Overall, the addition of a high concentration of phytase to broilers fed adequate concentrations of non-phytate P resulted in improved growth performance early with a reduction in this effect over time. Mucosal mucin-2 expression was increased with high-concentration phytase feeding across both lines, but IL-1β mRNA expression was reduced in the duodenum of broilers fed high concentrations of phytase, suggesting that the increased performance noted might be related to decreased inflammation.

The effects of a Bacillus licheniformis and phytase mixture added to broiler diets on growth performance, nutrient digestibility, and cecal microecosystem

“…Likewise, the valuable role of phytase, as one of the most frequently used feed additives globally, is widely described in the available literature (Cowieson et al, 2017;Konieczka et al, 2020;Ptak et al, 2015). It should be highlighted that phytase administration not only releases phosphorus and myo-inositol from feed materials of plant origin that are rich in phytate but also affects the functionality of the GIT, including nutrient utilization (Sommerfeld et al, 2018), physiological (Gonzalez-Uarquin et al, 2020), immunological (Jiang et al, 2018), and microbiological (González-Ortiz et al, 2020) responses. It should be highlighted that feed additives are not used alone, but from a practical point of view, several supplements are used during the same nutritional period, such as coccidiostats, exogenous enzymes (carbohydrases and/or phytase), probiotics, prebiotics, and phytobiotics.…”