Effect of dietary calcium level and source on mineral utilisation by piglets fed diets containing exogenous phytase

Abstract

Calcium and phosphorus are essential minerals, closely linked in digestive processes and metabolism. With widespread use of low P diets containing exogenous phytase, the optimal dietary Ca level was verified. The 40-day study evaluated the effects of Ca level (4, 7 and 10 g/kg diet) and Ca source (Ca from CaCO and from Lithothamnium calcareum) on mineral utilisation in 72 piglets (7.9 ± 1.0 kg BW) fed an exogenous phytase containing diet with 2.9 g digestible P/kg. Measured parameters were growth performance, stomach mineral solubility, bone breaking strength and urinary, serum and bone mineral concentration. The apparent total tract digestibility of minerals was also assessed in the two diets with 7 g Ca/kg, using 12 additional pigs. Regardless of Ca source, increasing dietary Ca impaired feed conversion ratio, increased urinary pH, increased serum and urinary Ca, decreased serum and urinary P, decreased serum Mg and increased urinary Mg, increased serum AP activity, decreased bone Mg increased bone Zn. Bone breaking strength was improved with 7 compared to 4 g Ca/kg. Compared to CaCO , Ca from Lithothamnium calcareum increased serum Mg and with, 10 g Ca/kg, it limited body weight gain. The dose response of Ca in a diet with 2.9 g digestible P/kg and including exogenous phytase indicated that: (i) a low dietary Ca was beneficial for piglet growth, but was limiting the metabolic use of P; (ii) a high dietary Ca level impaired P utilisation; (iii) the optimal P utilisation and bone breaking strength was obtained with a dietary Ca-to-digestible P ratio of 2.1 to 2.4:1; (iv). Increasing dietary Ca reduced Mg utilisation, but not Zn status, when fed at adequate level. Finally, Ca from Lithothamnium calcareum had similar effects on Ca and P metabolism as CaCO , but impaired growth when fed at the highest inclusion level.

Dietary Calcium to Digestible Phosphorus Ratio for Optimal Growth Performance and Bone Mineralization in Growing and Finishing Pigs

“…This would also be the case for supplemented Ca. Thus, as previously observed in post-weaning piglets [19], dietary Zn recommendations do not need to be adapted according to dietary Ca levels susceptible to be realistic in pig diets.…”

“…Dry ashed feed and Mc were solubilized with nitric acid and their mineral concentration was analyzed according to the European Standard EN 155510:2008 using an inductively coupled plasma optical emission spectrometer (ICP-OES, Optima 7300 DV, Perkin-Elmer, Schwerzenbach, Switzerland). Phytic acid content and phytase activity in diets were determined as previously described by Schlegel and Gutzwiller [19]. The serum and urine samples were assayed using commercially available kits according to manufacturer's instruction on a BT1500 autoanalyzer (Biotecnica Instruments S.p.A., Roma, Italy) to determine, creatinine (Biotecnica Instruments S.p.A., Roma, Italy), inorganic Ca and inorganic phosphate (Greiner Diagnostic GmbH, Langenthal, Switzerland) concentrations.…”

“…The present data indicate that the diets with Ca:dP ratios of respectively 2.5 and 2.8:1 were adequate for growth and sufficient for an optimal use of P, whereas 2.8:1 permitted to improve bone mineralization (especially ash concentration, volumetric density). An excess in dietary Ca can lead to increased urinary Ca and depressed serum P levels [5,19], thus resulting in impaired dietary P efficiency. This negative effect was not observed with 2.8:1, suggesting that higher Ca:dP ratios are required to limit the dietary use of P.…”

Evaluation of serum parameters to predict the dietary intake of calcium and available phosphorus in growing pigs

“…The importance of the dietary Ca and P supply and the impact on their systemic availability and skeletal mineralization in pigs are well known ( van Riet et al, 2013 ; Schlegel and Gutzwiller, 2017 ). From the available literature data, it was not clear how reliably serum parameters that are related to the Ca and P homeostasis can be used to predict the dietary supply with Ca and aP.…”

Lithothamnion calcareum Nanoparticles Increase Growth of Melon Plants

“…Lithothamnion calcareum has been used in different ways as animal nutrition (Carlos et al, 2011;Ucrós et al, 2012;Hagg et al, 2013;Lopes et al, 2013;Schlegel and Gutzwiller, 2017), herbal medicines (Goetz, 2008), biopolymers (Thangavelu and Subramani, 2016) and cosmetics (Dias, 2000). In agriculture, L. calcareum products have been applied as fertilizers and soil acidity…”