[1] BICALHO R C,MACHADO V C,CAIXETA L S.Lameness in dairy cattle:a debilitating disease or a disease of debilitated cattle?A cross-sectional study of lameness prevalence and thickness of the digital cushion[J].Journal of Dairy Science,2009,92(7):3175-3184.

[2] CHRISTODOULOPOULOS G.Foot lameness in dairy goats[J].Research in Veterinary Science,2009,86(2):281-284.

[3] HEYMERING H W.A historical perspective of laminitis[J].Veterinary Clinics of North America:Equine Practice,2010,26(1):1-11.

[4] JOHNSON P J,TYAGI S C,KATWA L C,et al.Activation of extracellular matrix metalloproteinases in equine laminitis[J].Veterinary Record,1998,142(15):392-396.

[5] KYAW-TANNER M,POLLITT C.Equine laminitis:increased transcription of matrix metalloproteinase-2 (
MMP-2) occurs during the developmental phase[J].Equine Veterinary Journal,2004,36(3):221-225.
[6] LOFTUS J P,BELKNAP J K,BLACK S J.Matrix metalloproteinase-9 in laminae of black walnut extract treated horses correlates with neutrophil abundance[J].Veterinary Immunology and Immunopathology,2006,113(3/4):267-276.
[7] MUNGALL B A,POLLITT C C.Zymographic analysis of equine laminitis[J].Histochemistry and Cell Biology,1999,112(6):467-472.

[8] MALEMUD C J.Matrix metalloproteinases (MMPs) in health and disease:an overview[J].Frontiers in Bioscience:A Journal and Virtual Library,2006,11:1696-1701.
[9] 中华人民共和国农业部.NY/T 816-2004肉羊饲养标准[S].北京:中国农业出版社,2004.
[10] 熊本海,庞之洪,赵峰,等.中国饲料成分及营养价值表(2014年第25版)制订说明[J].中国饲料,2014(21):29-39.
[11] POLLITT C C.Basement membrane pathology:a feature of acute equine laminitis[J].Equine Veterinary Journal,1996,28(1):38-46.

[12] JOHNSON P J,KREEGER J M,KEELER M,et al.Serum markers of lamellar basement membrane degradation and lamellar histopathological changes in horses affected with laminitis[J].Equine Veterinary Journal,2000,32(6):462-468.
[13] QIN W L.Determ naton of rumen volatile fatty acids by means of gas chromatography[J].南京农业大学学报,1982,4:110-116.
[14] 张龙翔,张庭芳,李令媛.生化实验方法和技术[M].北京:人民教育出版社,1981.
[15] KHAFIPOUR E,KRAUSE D O,PLAIZIER J C.A grain-based subacute ruminal acidosis challenge causes translocation of lipopolysaccharide and triggers inflammation[J].Journal of Dairy Science,2009,92(3):1060-1070.

[16] CHOMCZYNSKI P,SACCHI N.Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction[J].Analytical Biochemistry,1987,162(1):156-159.
[17] LIU J H, XU T T,LIU Y J,et al.A high-grain diet causes massive disruption of ruminal epithelial tight junctions in goats[J].American Journal of Physiology:Regulatory,Integrative and Comparative Physiology,2013,305(3):R232-R241.
[18] OWENS F N,SECRIST D S,HILL W J,et al.Acidosis in cattle:a review[J].Journal of Animal Science,1998,76(1):275-286.
[19] KRAUSE K M,OETZEL G R.Understanding and preventing subacute ruminal acidosis in dairy herds:a review[J].Animal Feed Science and Technology,2006,126(3/4):215-236.
[20] 刘丹,吴跃明,陈建海.反刍动物瘤胃酸中毒及其防治研究进展[J].中国饲料,2004(4):8-10.
[21] 张瑞阳,王东升,朱伟云,等.奶牛静脉血内毒素浓度及其与产奶量的相关性[J].动物营养学报,2012,24(5):822-827.
[22] PIPERI C,PAPAVASSILIOU A G.Molecular mechanisms regulating matrix metalloproteinases[J].Current Topics in Medicinal Chemistry,2012,12(10):1095-1112.

[23] SIWIK D A,CHANG D L F,COLUCCI W S.Interleukin-1β and tumor necrosis factor-α decrease collagen synthesis and increase matrix metalloproteinase activity in cardiac fibroblasts in vitro[J].Circulation Research,2000,86(12):1259-1265.

[24] NEE L E,MCMORROW T,CAMPBELL E,et al.TNF-α and IL-1β-mediated regulation of MMP-9 and TIMP-1 in renal proximal tubular cells[J].Kidney International,2004,66(4):1376-1386.

[25] TOTH M,CHVYRKOVA I,BERNARDO M M,et al.Pro-MMP-9 activation by the MT1-MMP/MMP-2 axis and MMP-3:role of TIMP-2 and plasma membranes[J].Biochemical and Biophysical Research Communications,2003,308(2):386-395.