Manganese Utilization in the Chick: Effects of Excess Phosphorus on Chicks Fed Manganese-Deficient Diets

Abstract

Young chicks were used in a 16-d feeding study to evaluate the effects of excess dietary P on Mn utilization. The basal casein-dextrose diet (1.4 mg Mn/kg) was supplemented with 0, 3.5, 7.0, or 10.5 mg Mn/kg from MnSO4.H2O and was fed in the absence or presence of .8% excess dietary P (equal P contributions from KH2PO4 and NaH2PO4). Diets containing .8% excess P were also supplemented with .8% excess Ca (CaCO3) to keep the Ca:P ratio above 1:25 so as to prevent anorexia associated with excess dietary P per se. Both growth rate and total tibia Mn responded linearly (P < .01) to Mn supplementation in chicks fed the normal level of P, but those fed excess P responded erratically. Excess P did not affect growth or tibia Mn in chicks fed the basal diet, but birds fed diets with supplemental inorganic Mn grew slower (P < .01) and had lower (P < .01) quantities of Mn in tibia when excess P was supplemented. Manganese content in the tibia of chicks fed excess P was 55% of that in chicks fed an adequate level of P.

The Role of Zinc, Manganse and Copper in Rumen Metabolism and Immune Function: A Review Article

“…However, while virginiamycin and other antibiotics are currently used as feed additives for ruminants [42], their role in Mn absorption in cattle remains unknown. According to [43], the intestinal absorption of Mn is negatively affected by dietary levels of Ca and P. Similar results were found by [44], who found a 45% reduction in Mn in the tibia of chicks fed excess Ca and P. However, further evidence provided by [45] indicated that while P has a negative effect on Mn absorption, no deleterious effects on Mn metabolism are obtained with excess of dietary Ca, but effects of Ca and P are difficult to distinguish since diets are usually enriched with both minerals to maintain a Ca:P physiological ratio [9].…”

Bioavailability of amino acid-chelated and glass-embedded manganese to rainbow trout, Oncorhynchus mykiss (Walbaum), fingerlings

“…1989) and chicks (Black et al. 1984a,b; Henry, Ammerman & Miles 1986, 1989; Scheideler 1991; Baker & Oduho 1994), Mn content of the tissues increased with the increment of dietary Mn. The findings of the present study demonstrated that whole‐body and bone Mn depositions in fish fed Mn‐Am were higher than the other sources, except for the bone Mn content of the group supplemented with MnSO 4 at 14 mg kg −1 .…”