Supplementing corn or corn-barley diets with an E. coli derived phytase decreases total and soluble P output by weanling and growing pigs

Abstract

. 2007. Supplementing corn or corn-barley diets with an E. coli derived phytase decreases total and soluble P output by weanling and growing pigs. Can. J. Anim. Sci. 87: 353-364. The efficacy of an E. coli derived phytase on phosphorus (P) digestibility and excretion, on the form of the P excreted, and the optimal dietary calcium (Ca):P ratio was examined. In exp. 1, 63 barrows (40.4 ± 1.9 kg) were assigned to receive one of 21 treatments arranged as a 3 × 7 factorial. Treatments consisted of three Ca levels (0.50, 0.60 and 0.70%) and seven phytase treatments [0, 250, 500, 1000 and 2000 FTU kg -1 of an E. coli-derived phytase and 500 FTU kg 1 of an A. niger phytase added to a P deficient (0.37% P) diet or 0 FTU phytase kg -1 added to a P adequate (0.53% P) diet]. In exp. 2, 144 pigs (6.52 ± 0.75 kg), received a P adequate (0.60% P) diet or a P deficient (0.44% P) diet supplemented with 0, 250, 500, 1000 or 2000 FTU phytase kg -1 for a 28-d trial. A subset of 36 barrows was then fed the same diets in a balance trial. In exp. 3, 36 barrows (7.1 ± 0.75 kg) were assigned to one of six treatments arranged as a 2 × 3 factorial (0 or 500 FTU of phytase kg -1 ; 1.0, 1.6 or 2.2 Ca:P ratio). In exp. 1, P digestibility improved from 21 to 54% with increasing phytase (quadratic; P < 0.05). Supplementing the diet with 500 FTU phytase kg -1 decreased the output of total and soluble P by 25% in exp. 2 and to a similar extent in exp. 3 at the lowest Ca:P ratio (P < 0.05). The effect of phytase on total P digestibility was mitigated as the dietary Ca:P ratio increased in exp. 3. Supplementation of swine diets with an E. coli derived phytase decreases output of total and soluble forms of P, but this effect is reduced at high dietary Ca:P ratios. . Dans le cadre d'une deuxième expérience, les auteurs ont donné à 144 porcs (6,52 ± 0,75 kg) une ration contenant suffisamment de P (0,60 %) ou carencée en P (0,44 %) et enrichie avec 0, 250, 500, 1 000 ou 2 000 FTU de phytase par kg pendant 28 jours. Un sous-échantillon de 36 castrats a ensuite reçu la même ration dans le cadre d'un essai sur le bilan alimentaire. Enfin, dans une troisième expérience, 36 castrats (7,1 ± 0,75 kg) ont été répartis entre six traitements dans une disposition factorielle 2 × 3 (0 ou 500 FTU de phytase par kg; ratio Ca:P de 1,0, 1,6 ou 2,2). Dans la première expérience, la digestibilité du P est passée de 21 % à 54 % avec le relèvement de la dose de phytase (quadratique; P < 0,05). Ajouter 500 FTU de phytase par kg à la ration a diminué l'excrétion de P total et de P soluble de 25 % dans la deuxième expérience et presque autant dans la troisième, au plus faible ratio Ca:P (P < 0,05). Dans cette dernière expérience, la hausse du ratio Ca:P atténue l'incidence de la phytase sur la digestibilité du P total. Enrichir l'alimentation des porcs avec une phytase dérivée de E. coli diminue l'excrétion du P total et du P soluble, mais dans une moindre mesure lorsque le ratio Ca:P est élevé.

Effects of dietary supplementation of exogenous multi-enzyme mixture containing carbohydrases and phytase on growth performance, energy and nutrient digestibility, and selected mucosal gene expression in the small intestine of weanling pigs fed nutrient deficient diets

“…In addition, supplementation of diets with phytase results in increased plasma inorganic P (Adeola 1995;Gentile et al 2003;Beaulieu et al 2007). In this study, we confirmed that pigs fed diets with higher dietary P and Ca also had higher serum P and Ca concentrations.…”

Phosphorus utilization and characterization of excreta from swine fed diets containing a variety of cereal grains balanced for total phosphorus1

“…Typically, when swine diets are not in excess of the dietary P requirement, very little P is excreted in the urine because of reabsorption of P in the kidneys. It was reported previously that in swine, urine P was less than 0.5% of TP excreted (Baxter et al, 2003;Beaulieu et al, 2007); thus, the contribution from urine would be very small. Typically, manure (mixture of feces and urine) is stored for a period of time before land application.…”

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

“…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%). In pigs, Beaulieu et al (2007) found that E. coli phytase reduced total P and soluble P outputs, but high Ca:P ratios diminished this effect.…”