Fig. 1

Visna maedi (VM) lesions in udder sections. a: healthy mammary gland. No inflammatory infiltrate is observed. HE. 20X b: moderate lesions (++). Presence of inflammatory cells in mammary interstitium and within epithelial cells.40X c: severe lesions (+++) with high quantity of lymphocytes and macrophages producing acini destruction. 40X d: anti-gp135 immunohistochemistry in udder with minimal lesions. Black arrow indicates a positive macrophage-like cell within the intertitium with a few inflammatory cells in the surroundings. 40X. e anti-p28 of CAEV/VMV immunohistochemistry in udder samples with severe lesion (+++). 40X. f: positive cell in the acinar lumen. No positivity is observed in epithelial cells