迷走神經消化不良Vagal indigestion
• 慢性狀態，發作慢Chronic condition, slow onset
• 攝取物質無法適當地從瘤胃移動到皺胃，或從皺胃進到幽門Ingesta are not properly transported from the rumen to abomasum or from abomasum to pylorus
• 大量的攝取物質、液體+/-氣體主要蓄積在瘤胃中(也在其他前胃和皺胃中) Large amounts of ingesta, fluid +/- gas accumulate mainly in rumen (also in other forestomachs and abomasum)
• 造成腹部脹大Result is abdominal distension
─ 病因學/致病機轉Vagal indigestion – aetiology/ pathogenesis
ü 未完全瞭解Not fully understood
ü 迷走神經在食道兩側活動，造成前胃和皺胃分佈的神經靜止Vagus nerve runs along both sides of oesophagus and terminates by innervating forestomachs and abomasum
ü 此處神經的功能受損，會引起臨床症狀Impairment in function of this nerve may result in clinical signs
ü 蜂巢胃的移動性發生機能性損傷，以及食道溝的功能障礙(蜂巢胃黏附)是最主要的原因Mechanical impairment of reticular motility and oesophageal groove dysfunction (reticular adhesions) most important cause
ü TPR是主要造成消化不良的原因TRP is responsible for most cases of vagal indigestion
ü 其他原因包括Other causes include：
‧蜂巢胃壁的放線桿菌病Actinobacillosis of reticular wall
‧心臟的纖維乳突狀瘤Fibropapilloma of the cardia
‧腹膜炎(皺胃潰瘍穿孔) Peritonitis (perforating abomasal ulcer)
‧感染或贅瘤Infections or neoplasia
‧橫隔膜破裂、腹膜炎 Ruptured diaphragm, pleurisy
‧肝膿瘍Liver abscess
‧牛隻死後剖檢可能找不出病因No cause may be seen on post mortem
─ 臨床症狀Vagal indigestion – clinical signs
p 瘤胃腫大Enlarged rumen
‧有/無氣泡沫的氣體蓋使背囊擴張而腫大Distended dorsal sac with gas cap ± frothy ingesta
‧腹囊脹大，從後方擠壓使瘤胃呈L形 ─「papple」形Ventral sac then enlarges creating an L shaped rumen from behind –”papple” shape
‧後期病例─直腸檢查顯示右腹囊脹大Advanced cases – rectal exam reveals enlarged right ventral sac
‧間歇性腹部膨脹，在數週 至 數月的時間內會轉成慢性Abdominal distension intermittent but becomes chronic over weeks – months
‧懷孕末期的子宮脹大，能遮蔽住瘤胃脹大的右腹囊Uterine enlargement in late pregnancy may mask distension of right ventral sac of rumen
腫脹的背囊(左側) Enlarged dorsal sac (left side) (Photo: Murdoch University)
腫脹的腹囊(右側)Enlarged ventral sac (right side) (Photo: Murdoch University)
─ 臨床症狀Vagal indigestion – clinical signs
ü 瘤胃收縮頻率弱 (3~6次/分鐘) Frequent weak rumen contractions (3 – 6/ min)
ü 食慾減退(視腹部腫大程度及排便量而定) ↓ Appetite (varies with amount of abdominal distension and faeces produced)
ü 少量的黏糊便或水便Small amount of pasty or runny faeces
ü 失重Weight loss
ü 產乳量降低↓ milk production
ü 可能出現心跳變慢 (40 bpm) Bradycardia (40bpm) may be present
─ 診斷 Vagal indigestion – diagnosis
ü 無特定的實驗室檢測No specific laboratory tests
ü 嗜中性白血球+/-左移表示炎症反應 Neutrophilia +/- left shift indicates inflammation
ü 血漿蛋白及纖維素原增加↑ plasma protein and fibrinogen
ü 球蛋白增加 = 蜂巢胃膿瘍或肝膿瘍？↑ globulin = reticular or hepatic abscess?
ü 淋巴肉瘤─ 持續性的淋巴球過多症Lymphosarcoma – persistent lymphocytosis
ü 幽門狹窄症─吸收物從皺胃逆流到蜂巢芻胃中，使瘤胃液中氯化物增加Pyloric stenosis - reflux of ingesta from abomasum into reticulorumen increases chloride content of rumen fluid
─ 預後及治療Vagal indigestion – prognosis and treatment
ü 預後差Poor to hopeless prognosis
ü 商業牛 ─ 送去屠宰Commercial cattle – salvage slaughter
ü 有價值的牛隻Valuable animals ─
‧再成水化物Rehydrate
‧考慮進行剖腹探查術以確認主因(左側，瘤胃切開術) Consider exploratory laparotomy to establish primary cause (left side, rumenotomy)
‧長期存活的牛隻以手術治療仍差(只在懷孕末期採用) Long term survival still poor with surgery (salvage procedure for late pregnancy cases)