Comparison of 3 phytases on energy utilization of a nutritionally marginal wheat-soybean meal broiler diet

Abstract

The net energy (NE) value may be a better measure than apparent metabolizable energy (ME) of the effect of supplemental phytase on energy utilization in broilers. The present study was conducted to assess the impact of 3 microbial phytases supplemented at an unconventionally high level (1,000 FTU/kg feed) on performance and NE of broilers using the indirect calorimetric method (IC). Four treatments included: 1) Control, formulated to be deficient in ME (12.35 MJ/kg in the starter diet; 12.56 MJ/kg in the grower diet), calcium (0.72% in the starter diet; 0.60% in the grower diet), and available phosphorus (0.25% in the starter diet; 0.20% in the grower diet); 2) control + intrinsically thermostable phytase A; 3) control + intrinsically thermostable phytase B; and 4) control + coated phytase C. A completely randomized design was employed. A total of 384 male broiler chicks were used, and each treatment had 6 replicates with 16 birds per replicate. The birds were reared until d 21 in floor pens with hardwood shavings. Thirty-two birds (8 birds per treatment) were randomly selected to determine heat production and NE (from 25-28 d) following a 3-d acclimatization in the respiratory chambers. Performance results at d 21 showed that supplementation with either of the 3 phytases improved body weight (P < 0.001) and feed intake (P < 0.05), and increased the relative weights of tibia ash (P < 0.05) and toe ash (P < 0.01). Phytases A and B increased the NE value of the diet (P < 0.05). It may be concluded that the negative effects imposed by calcium and available phosphorus down-specification can be compensated by phytase supplementation in general, and intrinsically thermostable phytases improve the ME and NE value. However, phytase did not reduce heat production, heat increment, or increase NE:ME in birds.

Performance, litter quality and gaseous odour emissions of broilers fed phytase supplemented diets

“…The lower weight of small intestine on d 24 with the addition of 1,000 or 1,500 FTU/kg phytase in diet observed in this study is similar to the finding by Wu et al. (2015) .…”

Dietary Supplementation with Phytase and Protease Improves Growth Performance, Serum Metabolism Status, and Intestinal Digestive Enzyme Activities in Meat Ducks

“…In addition, dietary supplementation with exogenous enzyme preparation could also reduce the variability between the calculated and analyzed nutrient compositions [13]. Furthermore, dietary supplementation with exogenous phytase in low-energy diets or protease in low-protein diets has been proven to exert beneficial influences on the growth performance of poultry, including increases in feed intake and body weight [13][14][15]. China is the main production area of ducks, most of which are meat ducks, and there is a great waste of feeds for meat ducks because of insufficient endogenous enzyme secretions and subsequent poor digestibility of feeds.…”

Valuation of the Nutritional Matrix by Phytase and Soy Gum in the Diet Formulation for Broiler Chickens

“…The unavailability of almost 2/3 of the phosphorus contained in ingredients of plant origin is because it is bonded to inositol, forming phytic acid or inositol hexaphosphate, which can form nutritionally important organic mineral complexes and represents one of the main anti-nutritional factors that affect nutrient availability for monogastric animals (COWIESON; WILCOCK; BEDFORD, 2011). An alternative to increase the availability of phosphorus and other complexed nutrients in the phytic acid molecule and the release of energy is the inclusion of exogenous enzymes in the feed, such as microbial phytases (MANOBHAVAN et al, 2015;WU et al, 2015).…”