Interaction of Calcium and Phytate in Broiler Diets. 2. Effects on Total and Soluble Phosphorus Excretion

Abstract

Dietary Ca has been reported to influence the amount of phytate excreted from broilers and affect the solubility of P in excreta. To address the effects of dietary Ca and phytate on P excretion, 12 dietary treatments were fed to broilers from 16 to 21 d of age. Treatments consisted of 3 levels of phytate P (0.10, 0.24, and 0.28%) and 4 levels of Ca (0.47, 0.70, 0.93, and 1.16%) in a randomized complete block design. Feed phytate concentrations were varied by formulating diets with 3 different soybean meals (SBM): a low-phytate SBM, a commercial SBM, and a high phytate Prolina SBM having phytate P concentrations of 0.15 to 0.51%. Fresh excreta was collected from cages during 2 separate 24-h periods; collection I commenced after the start of dietary treatments (16 to 17 d) and collection II followed a 3-d adaptation period (19 to 20 d). Ileal samples were also collected at 21 d. Excreta samples were analyzed for total P, water

Animal manure phosphorus characterization by sequential chemical fractionation, release kinetics and 31P-NMR analysis

“…Our results are in agreement with those of He et al (2007) and Leytem et al (2008b), who characterized P compounds in poultry and dairy manures by solution 31 P-NMR in NaOH + EDTA extracts. They found that in dairy manure, inorganic P was the major P fraction (64-73 %), followed by 6 % phytic acid, 14 to 22 % other monoesters, and 7 % phosphodiesters, whereas in the poultry manure, results showed that orthophosphate accounted for 51 to 63 %, phytic acid 24 to 33 %, other phosphomonoesters 6 to 12 %, and phospholipids and DNA 2 % each.…”

Effect of feeding diets containing a probiotic or antibiotic on broiler performance, intestinal mucosa-associated avian pathogenic E. coli and litter water-soluble phosphorus

“…This finding suggested that solubility of P in manures could be altered by microbial degradation of organic P fractions. The WSP content and the ratio of WSP:total P was also shown to be affected by the P composition of broiler litter (Leytem and Maguire, 2006). Leytem et al, (2008) subsequently showed that WSP in litter was strongly influenced by the phytate P content in litter, with steep linear reductions in WSP (as phytate P content) relative to total P in the litter increased.…”

“…The WSP content and the ratio of WSP:total P was also shown to be affected by the P composition of broiler litter (Leytem and Maguire, 2006). Leytem et al, (2008) subsequently showed that WSP in litter was strongly influenced by the phytate P content in litter, with steep linear reductions in WSP (as phytate P content) relative to total P in the litter increased. Therefore, dietary and other factors that alter the amount of phytate P excreted in the manure alter the solubility of the P therein.…”

“…The form of P in the manure has important environmental consequences, as a reduction in the proportion of manure P as phytate has been shown to be strongly correlated with increased manure water soluble P (Leytem et al, 2008) and potentially result in greater P losses from surface applied manures that have not had sufficient time to react with soil and be converted into more stable forms (Penn et al, 2004;Sturgul and Bundy, 2004). The aim of the present experiment was to compare the effects of supplementing broiler diets with a probiotic containing three Bacillus subtilis strains, or an antibiotic (zinc bacitracin; BMD), on the performance, intestinal mucosa-associated APEC levels, intestinal morphology and litter water-soluble phosphorus (WSP).…”

Consequences of calcium interactions with phytate and phytase for poultry and pigs

“…However, Leytem et al (2006) found that concentrations of water soluble (extractable) P and phytate-P, as proportions of total P in poultry excreta, are linearly related (r 2 = 0.94) in poultry excreta and both dietary Ca levels and Ca:available P ratios are critical to the water soluble P content of broiler litter (Leytem et al, 2007a). Subsequently, Leytem et al (2007b) reported that reducing phytate levels in broiler diets from 2.8 to 1.0 g kg − 1 with low-phytate soybean meal reduced total P (62.7%), water soluble P (66.4%) and phytate-P (74.6%) in excreta by broadly similar magnitudes. Also, increasing dietary Ca from 4.7 to 11.6 g kg − 1 increased the amount of phytate-P (43.0%) excreted but decreased the output of water soluble P (57.0%).…”