Chronic laminitis as the predisposing factor for other digital diseases in dairy cows

慢性蹄叶炎是奶牛其他指部疾病的诱发因素

• 批准号: 03454111
• 负责人: SASAKI Nobuo
• 金额: $ 4.22万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03454111/
• 关键词: Dairy cow; Digital disease; Subclinical laminitis; Chronic laminitis; Arteriography; High concentrate feeding; Endotoxin; Histology; 蹄底潰瘍; 分娩; 準臨床レベルの蹄葉炎; 蹄球びらん; 過長蹄

A recent increase in incidence of various types of hoof disease in dairy cows has caused a significant ecomic damage on the dairy farms in Japan. From previous reports, chronic or subclinical laminitis has been indicated as an important predisposing factor for this problem and endotoxin produced in the rumen may be thought as one of the etiologic factors for laminitis.In this research project, we initially obtained the digits of dairy cows, which were thought to be raised in the typical Japanese dairy farms, from slaughterhouses and the presence of chronic or subclinical laminitis was investigated. As a result, 52.9% of the digits were demonstrated revealed histologically as subclinical laminitis and 29% as chronic laminitis. Arteriography of these digits also revealed the extended or narrowed artery to the sensitive laminae, which may indicate that the chronic circulatory disturbance is the important factor of the various hoof diseases. In the next step, the endotoxin (ET) levels in the ruminal fluid and peripheral blood during the pre- and postparturient period were determined. According to the increase in feeding concentrates after parturition, ruminal ET considerably rised and the blood ET showed episodic increase during the first two weeks after parturition. However, each ET levels did not necessarily coincided. In goats given starch as a concentrate via the rumen fistula, the similar changes in ruminal and blood ET levels were observed and better coincidence could be observed between the two levels. These results might indicate the hypothesis that the increased ET according to the increase in high concentrate feeding is absorbed via the digestive tract and plays an important roll in the etiology of chronic or subclinical laminitis which may result in poor horn quality and other hoof diseases such as sole ulcer.

近年来，日本奶牛蹄病的发病率不断上升，给奶牛场造成了严重的经济损失。从以往的报道来看，慢性或亚临床蹄叶炎是引起这一问题的重要诱因，而瘤胃内产生的内毒素可能是引起蹄叶炎的病因之一。从屠宰场和慢性或亚临床蹄叶炎的存在进行了调查。结果显示，52.9%的手指表现为亚临床蹄叶炎，29%为慢性蹄叶炎。动脉造影也显示了这些趾的敏感层动脉的扩张或狭窄，这可能表明慢性循环障碍是各种蹄疾病的重要因素。在接下来的步骤中，在分娩前后的瘤胃液和外周血中的内毒素（ET）水平进行了测定。随着产后精料的增加，瘤胃内ET显著升高，产后前两周内血液ET呈阶段性升高。然而，每个ET水平并不一定一致。经瘤胃瘘管饲以精淀粉的山羊，其瘤胃内和血液中ET水平的变化趋势相似，且两者的一致性较好。这些结果可能表明这样的假设，即根据高浓缩饲料的增加，ET增加通过消化道吸收，并在慢性或亚临床蹄叶炎的病因学中起重要作用，这可能导致角质量差和其他蹄疾病，如蹄溃疡。

项目成果

Sasaki,N.,Nakayama,H.,Nishimura,R.et al: "Histopathologic changes in the sensitive laminae after an infusion of endotoxin in goats" J.Vet.Med.Sci.(in prepartion).

Sasaki, N.、Nakayama, H.、Nishimura, R.等人：“山羊输注内毒素后敏感层的组织病理学变化”J.Vet.Med.Sci.（准备中）。

Sasaki,N.,Nishimura,R.,Kadosawa,T.et al: "Arteriography of the digit of the dairy cows with chronic/subclinical laminitis" J.Vet.Med.Sci.(in prepartion).

Sasaki，N.，Nishimura，R.，Kadosawa，T.et al：“患有慢性/亚临床蹄叶炎的奶牛手指动脉造影”J.Vet.Med.Sci.（准备中）。

Sasaki, N., Nishimura, R., Kadosawa, T.et al: "Arteriography of the digit of the dairy cows with chronic / subclinical laminitis" J.Vet.Med.Sci.(in preparation).

Sasaki, N.、Nishimura, R.、Kadosawa, T.等人：“患有慢性/亚临床蹄叶炎的奶牛手指动脉造影”J.Vet.Med.Sci.（准备中）。

Sasaki, N., Nakayama, H., Nishimura, R.et al: "Histopathologic changes in the sensitive laminae after an infusion of endotoxin in goats" J.Vet.Med.Sci.(in preparation).

Sasaki, N.、Nakayama, H.、Nishimura, R.等人：“山羊输注内毒素后敏感层的组织病理学变化”J.Vet.Med.Sci.（准备中）。

Mochizuki,M.,Sasaki,N.,Nakayama,H.et al: "Histopathologic findings of the digits of dairy cows in Japan" J.Vet.Med.Sci.(under submitted).

Mochizuki,M.、Sasaki,N.、Nakayama,H.et al：“日本奶牛指部的组织病理学发现”J.Vet.Med.Sci.（已提交）。