OBJECTIVETo evaluate and compare the histopathology effects and mechanisms of the methods of "invigorating spleen to remove phlem & promoting blood circulation to remove meridian obstruction" and "invigorate the kidney & promoting blood circulation to remove meridian obstruction" preventing hormone induced femoral head necrosis in hens.

METHODSSixty-four healthy hens were randomly divided into 4 groups: blank control group, model group, Jianpi group (with therapeutics of invigorating spleen to remove phlem), Bushen group (with the effect of warming kidney for duresis). All hens were injected intramuscularly with Medrat once a week for 16 weeks but normal saline in blank control group. Bilateral femoral heads were dissected on 8 weeks or 16 weeks. Paraffin tissue sections were prepared to detect histopathologic change with hematoxylin and eosin, or mason staining.

RESULTSHistological analysis showed that Huogu recipe I and Huogu recipe II can promote osteogenesis and repair osteonecrosis, increase blood circulation of bone marrow, and inhibit pimelosis of bone marrow. Compared with blank control group, the areas of adipose cells increased significantly (t = -12.9, P < 0.01), the area of immature collagen increased significantly (t = -2.0, P < 0.05) and the ratio of empty lacuna in medullary cavity (t = -3.7, P < 0.05). Compared with model group, both the area of adipose cells and the ratio of empty lacuna decreased in Jianpi group and Bushen group (F = 26.8, 13.5, P < 0.01), so it was with the Bushen group immature collagen (F = 4.6, P < 0.01).

CONCLUSIONBoth the methods of "invigorating spleen to remove phlem & promoting blood circulation to remove meridian obstruction" and "invigorate the kidney & promoting blood circulation to remove meridian obstruction" can prevent hormone induced femoral head necrosis. The time taking effect in the method of "invigorating spleen to remove phlem" was shorter.