Influence of high dose of phytase and an emulsifier on performance, apparent metabolisable energy and nitrogen retention in broilers fed on diets containing soy oil or tallow

Abstract

The effects of high dose of microbial phytase and an emulsifier on the performance, apparent metabolisable energy (AME) and nitrogen (N) retention in broilers fed on diets containing different fat sources were examined in a 5-week trial. Two fat sources (soy oil and tallow), two inclusion levels of E. coli phytase (500 or 1000 phytase units (FTU)/kg diet) and two inclusion levels of lysolecithin emulsifier (0 or 3.5 g/kg of diet) were evaluated in a 2 × 2 × 2 factorial arrangement of treatments. Throughout the 5-week trial, soy oil supplementation improved weight gain and feed per gain compared with tallow, but had no effect on feed intake. The high dose of phytase increased the weight gain and feed intake and lowered the feed per gain during d 1-21, but had no effect on performance parameters over the whole trial period. An effect of emulsifier was observed for feed intake during d 1-21 and over the whole trial period. Addition of emulsifier increased feed intake compared with diets without emulsifier. During weeks 1, 2, 3 and 5, birds fed on soy oil-based diets had higher nitrogen-corrected AME (AMEN) compared with those fed on tallow-based diets. During weeks 2, 3 and 5, the effect of phytase was significant for AMEN, with the high dose increasing the AMEN. During week 2, AMEN was increased with emulsifier addition. During weeks 1, 2, 3 and 5, birds fed on soy oil-based diets had higher fat retention compared with those fed on tallow-based diets. The high dose of phytase improved the retention of fat during week 5 and the addition of emulsifier resulted in higher fat retention during week 1. During weeks 2, 3 and 5, an interaction between fat source × phytase × emulsifier was observed for N retention. In soy oil-based diets, emulsifier plus 1000 FTU/kg phytase increased N retention compared with other groups, while in tallow-based diets, emulsifier addition increased N retention in diets with 500 FTU/kg, but not in 1000 FTU/kg diet. Overall, the present data suggest that the dietary fat source influenced performance, AMEN and fat retention in broiler chickens. There is opportunity to improve bird performance during d 1-21, AMEN and fat retention with higher doses of microbial phytase. Addition of the emulsifier increased the AMEN during week 2 and tract retention of fat during week 1, but this effect was not translated into improvements in performance.

The addition of lysolecithin to broiler diets improves growth performance across fat levels and sources: a meta-analysis of 33 trials

“…However, the magnitude of effect on FCR following on top supplementation with lysophospholipids varied between studies, ranging from 8 points in reduction to a 4 point increase vs. an unsupplemented control. This variation was in line with the response seen in other published studies (Chen et al 2019;Jansen et al 2015;Zaefarian et al 2015), and is likely due to the inherent variability in growth response to nutritional additives. Even when assessing much larger datasets than currently presented, models quantifying factors responsible for bird response to phytase enzyme addition could only account for 64-72% of total variation (Rosen 2006).…”

“…Given the contradictions in the literature and in this analysis, it is clear that the relationship between lysolecithin supplementation and dietary fat source and U:S ratio has not been conclusively described and merits further research. A number of authors have found significant differences in AMEn between animal fats and soybean oil (Jansen et al 2015;Zaefarian et al 2015;Zhang et al 2011), and have associated this with differences in the degree of saturation between the fat types (Wiseman and Salvador 1991). However, when looking at the effect of fat saturation on performance, Firman et al (2008), among others, reported few statistical differences between fat sources.…”

“…When compared with lecithin, lysophospholipids are more hydrophilic, have better oil-in-water emulsifying properties (Joshi et al 2006;Liu and Ma 2011) and therefore, are more able to improve the digestion of fats and oils. Previous research with lysolecithin in broiler diets has demonstrated improved weight gain and feed conversion ratio (FCR) (Zaefarian et al 2015;Zampiga et al 2016; Allahyari-Bake and Jahanian 2016), while others have reported increases in apparent metabolisable energy (AME) (Melegy et al 2010;Jansen et al 2015).…”

Use of emulsifier and lipase in feeds for broiler chickens

“…In addition, it increases the formation of protein channels and the permeability of the cell membrane (ZAMPIGA et al, 2016). However, Zaefarian et al (2015) reported that the increase in lipid digestibility with the use of an emulsifier in broiler feed during the initial phase might not be sufficient to increase the use of the apparent metabolisable energy and, in addition, the lack of an effect on digestibility is related to the short duration of the study, which might not reflect the performance of the birds. A similar result was observed in the present experiment, where the use of emulsifier was more effective in the final phase.…”

Effect of dietary supplementation of lysophospholipids on productive performance, nutrient digestibility and carcass quality traits of broiler chickens

“…The emulsifier does not affect the feed intake as birds consumed a similar daily amount of feed (116.7 vs. 116.0 vs. 115.5 g/bird/d, respectively for CON, CONST and VARI groups), while Zaefarian et al (2015) found a significant increase in feed consumption in broilers fed diets containing 3.5 kg/ton of lysophospholipids. No effect of emulsifiers on feed intake was previously reported by Guerreiro Neto et al (2011), Aguilar et al (2013) and Zhang et al (2011) who used respectively a casein, a nonionic and lysophosphatidylcholine emulsifier.…”