Figure 2
From: Exogenous estradiol improves shell strength in laying hens at the end of the laying period
Localization of carbonic anhydrase (CA) activity in shell gland shown as black staining. Laying hens Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) treated with estradiol 3-benzoate or a placebo pellet at the end of the laying period. (a) Shell gland mucosal fold of 72-week-old LSL hen treated with estradiol pellet. Weak membrane-bound staining of tubular gland cells (G) (arrow) Bar = 20 μm. (b) Amount of CA staining in tubular gland cells of LSL and LB hens (n = 10). Results are expressed as mean ± SE. *(P < 0.05). (c) Shell gland mucosal fold of 72-week-old LSL hen treated with estradiol. No detectable staining in surface epithelium (S), capillaries with intense membrane-bound staining of endothelial cells (arrow) and capillaries with no staining (arrowhead). Bar = 20 μm. (d) Number of CA positive capillaries/mm2 in shell gland of LSL and LB hens (n = 10). Results are expressed as mean ± SE. *(P < 0.05).