The impact of dietary calcium content on phosphorus absorption and retention in growing pigs is enhanced by dietary microbial phytase supplementation. Issue 6 (28th March 2023)

• Record Type: Journal Article
• Authors: Hu, Yixin; Hendriks, Wouter; van Baal, Jurgen; Resink, Jan-Willem; Rodehutscord, Markus; Van Krimpen, Marinus M.; Bikker, Paul
• Is Part Of: British journal of nutrition. Volume 129:Issue 6(2023)
• Page Start: 955
• Page End: 966
• Publication Date: 2023-03-28
• Subjects: Calcium -- Phosphorus -- Phytase -- Gastrointestinal tract segments -- Pigs; Nutrition -- Periodicals; 572.4
• DOI: 10.1017/S0007114522001039
• Languages: English
• ISSNs: 0007-1145

Abstract

Abstract: Sixty growing male pigs were used to test the hypothesis that high dietary Ca content reduces P absorption to a greater extent in microbial phytase-supplemented diets via reducing inositol phosphate (IP) degradation and enhancing P precipitation. Pigs were equally allotted over diets with three Ca contents 2·0, 5·8 and 9·6 g/kg with or without microbial phytase (0 v . 500 FTU/kg) in a 2 × 3 factorial arrangement. Faeces and urine were collected at the end of the 21-d experimental period. Subsequently, pigs were euthanised and digesta quantitatively collected from different gastrointestinal tract (GIT) segments. Increasing dietary Ca content reduced apparent P digestibility in all GIT segments posterior to the stomach ( P < 0·001), with greater effect in phytase-supplemented diets in the distal small intestine ( P interaction = 0·007) and total tract ( P interaction = 0·023). Nonetheless, increasing dietary Ca to 5·8 g/kg enhanced P retention, but only in phytase-supplemented diets. Ileal IP6 degradation increased with phytase ( P < 0·001) but decreased with increasing dietary Ca content ( P = 0·014). Proportion of IP esters in total IP (∑IP) indicated that IP6/∑IP was increased while IP4/∑IP and IP3/∑IP were reduced with increasing dietary Ca content and also with a greater impact in phytase-supplemented diets ( P interaction = 0·025, 0·018 and 0·009, respectively). In all GIT segments, P solubility was increased with phytase ( P < 0·001) and tended to be reduced with dietary Ca content ( P < 0·096). Measurements in GIT segments showed that increasing dietary Ca content reduced apparent P digestibility via reducing IP degradation and enhancing P precipitation, with a greater impact in phytase-supplemented diets due to reduced IP degradation.