Apparent digestibility and retention of nutrients bound to phytate complexes as influenced by microbial phytase and feeding regimen in pigs

Abstract

Five barrows of approximately 45 kg BW, fitted with post-valvular T-cecum cannulas at the ileo-cecal junction, were assigned randomly to five treatments (5 x 5 Latin square design) to assess the effect of microbial phytase and feeding regimen (frequency and level) on the apparent digestibilities (total tract [ATTD] and ileal [AID]) and retention of nutrients. A corn-tapioca-soybean meal diet of low intrinsic phytase activity, containing no added inorganic P, was fed either without or with microbial phytase from Aspergillus niger var. Van Tieghem (800 phytase units/kg of diet) at different feeding frequencies (once, twice, or seven times per day) and feeding levels (2.3 vs 2.8 times the maintenance requirement for ME, i.e., 418 kJ ME/BW.75). Microbial phytase enhanced significantly the ATTD of DM, OM, CP, Ca, total P, and amino acids (except for cystine and proline). Also, the AID of total P, phytic acid, methionine, and arginine was increased (P < .05 or .01). As a consequence of adding this enzyme, the retention (grams/day) of N, Ca, and P was greater (P < .01) and their daily excretion was diminished by 5.5, 2.2, and 1.9 g/d, respectively. The feeding level exerted a minor effect on the ATTD and AID (except for methionine and cystine), although the retention (grams/day) of N, Ca, and P was greater (P < .01) at the higher level of feeding. The feeding frequency influenced significantly the ATTD of Ca, tryptophan, and isoleucine and the AID of phytic acid, cystine, arginine, isoleucine, and phenylalanine. Also, N retention (grams/day) was reduced in pigs fed once daily (P < .01).

Phosphorus equivalency value of microbial phytase in weanling pigs fed a maize-soyabean meal based diet

“…Growth performance, rib mineralization and P digestibility were all improved when phytase was added to the diet. This is in agreement with studies in the literature which have demonstrated increased daily gains and feed intakes (Beers and Jongbloed, 1992;Jongbloed et al, 1992;Qian, 1996, Yi et al, 1996), increased bone breaking strength or shear force Yi et al, 1996) and increases in P digestibility or retention (Hoppe et al, 1992;Lei et al, 1993a,b;Mroz et al, 1994;Kornegay and Qian, 1996;Yi et al, 1996) when pigs are fed diets supplemented with phytase.…”

Relação cálcio:fósforo disponível e níveis de fitase para poedeiras semipesadas no primeiro e segundo ciclos de postura

“…De acordo com Wu et al (2006), somente 20 a 50% do total do fósforo dos alimentos de origem vegetal se encontra disponível para aves, pois o restante se encontra na forma de fitato. O fitato, além reduzir a disponibilidade do fósforo, forma complexos insolúveis com as proteínas dietéticas (Ferket, 1993) e com cátions, como cálcio, cobre, zinco, magnésio, manganês e ferro presentes nos alimentos consumidos (Klasing, 1998), que adquirem resistência à digestão enzimática (Mroz et al, 1994), reduzindo a disponibilidade desses nutrientes.…”

Effects of Aspergillus fumigatus phytase on phosphorus digestibility, phosphorus excretion, bone strength and performance in pigs

“…Dietary microbial phytase supplementation can thus improve phytic-P digestive utilization and consequently reduce P pollution by animal excreta [17,18,23,37,38]. Furthermore, improved nutrient digestibility in animals fed supplemental phytase has been reported in pigs and in poultry [3,4,22,24,25,46,47].…”

“…AFP did not have significant effects on the DM and N faecal digestibilities. The effects of AFP on amino acid availability remain to be investigated by measurement of either ileal digestibility [24] or the gastrointestinal absorption of amino acids, in order to overcome the effects of the hindgut microflora on the amino acids availability.…”