Fig. 1From: Dietary vitamin D3 supplementation protects laying hens against lipopolysaccharide-induced immunological stressSerum calcium levels in vitamin D3-deficient and vitamin D3-sufficient laying hens. Data are presented as mean ± SEM (n = 6 /group). Bars with different letters (a, b) show a significant difference between VD3 deficiency and sufficiency (P < 0.05)Back to article page