1、.豬增生性腸炎(PPE,Procine Proliferative Enterpathy)又叫迴腸炎(Ileitis).不，這不是一種新病。但我們對它卻到最近才有完整的了解。我們發現迴腸炎是造成養豬業重大損失的疾病。.美國禮來大藥廠.這些疾病不相關豬增生性腸炎PPE增生性出血性腸炎PHE迴腸炎Ileitis壞死性腸炎Necrotic Enteritis出血性迴腸炎bloody form ileitis增生性腸道病變Proliferative Enteropathy水管腸道病Garden hose Gut豬腸道Porcine intestinal adenomatosis(PIA).這些疾病都是
2、同一種病原所引發的不同型態及臨床症狀 迴腸炎亞臨床型迴腸炎非出血型迴腸炎急性出血型迴腸炎.這些疾病可能是由許多不同病原所引發榛狀菌Campylobacter sputorum類棒狀菌微生物Campylobacter-like organism.1995年發現且正式命名 迴腸炎的致病原為一種專門寄生在腸道上皮細胞內的:細胞內寄生拉森菌細胞內寄生拉森菌Lawsonia Intracellularis免疫螢光.病原不明 診斷方法不明(僅能經由死後剖檢)容易與沙門氏菌或豬赤痢混淆 對於該病的亞臨床型及慢性型了解有限 豬場的流行狀況及經濟損失不明 罹病率及疾病在豬場的重要性被低估.最常被稱為增生性腸炎或
3、迴腸炎 仔豬離乳後的腸道疾病 目前已知是造成豬隻下痢及生長不良的重要疾病.細胞內寄生拉森菌Lawsonia Intracellularis 對腸道細胞具親和力，因而感染腸細胞 G(-)專性厭氧菌 專性細胞內寄生之細菌.拉森菌寄生於迴腸及結腸上段的腸道上皮細胞中 受感染的細胞開始不正常增生，增生細胞多為未成熟上皮細胞 增生的細胞使腸壁厚度增加 腸道失去正常的消化及吸收功能 其它細菌的二次感染.上皮細胞不正常增生不成熟的上皮細胞增生因而使腸壁不正常增厚增厚的腸壁影響腸道正常功能細菌性二次感染機會增加受感染的上皮細胞脫落後經由糞便排出並感染其它豬隻寄生於細胞內的拉森菌.潛伏期約2-3週 急性出血性迴
4、腸炎 亞臨床型迴腸炎亞臨床型慢性.又稱增生性出血性腸炎(PHE)急性 好發於後備母豬及肥育豬(15-17 週齡)長途運輸後或新進場母豬 好發於規模大豬場 雜菌清除後造成拉森菌增生?豬隻感染後 糞便呈現黑色瀝青狀 豬隻呈現蒼白貧血 高死亡率(約6-20%)未死亡可逐漸康復.亞臨床型迴腸炎最常發生於哺育豬(15-30 Kg體重)肥育前期豬隻次之生長性能不良 整齊度差 攝飼料減少 增重降低 籵肉比增加.慢性迴腸炎最常發生於肥育後期豬隻(30-70 Kg體重)哺育豬次之10-50%豬隻下痢呈現半固體軟便 顏色不規則 通常不帶血絲 糞便中含有壞死性組織病程可維持數天至數週逐漸變成壞死性腸炎,預後不良 體
5、重減輕,皮毛粗剛,生長不良 死亡.經常發生於哺育豬及肥育前期豬隻(20-50 Kg).病豬生長不良，整齊度差 10-50%豬隻呈現軟便至下痢 生長性能不良 飼養管理的改變經常造成疾病爆發 換欄或運輸 換料(攝飼料減少)停藥或換藥 溫差過太 密飼 黴菌毒素 可能的二次感染病原 梭菌 榛狀菌 大腸桿菌.人員散播人員散播污染的糞便鼠類傳播外來後備母豬外來後備母豬母豬傳播給仔豬平行感染平行感染鳥類傳播.豬隻消化道的吸收消化等功能受損增重降低料肉比增加整齊度下降 豬場生產線受阻 淘汰豬隻增加 死亡率增加1-5%治療投藥成本增加 人工及管理費用增加.Impact of ileitis on the per
6、formance.5 experimental infections.Ref:McOrist et al.,1997 Veterinary Record,140:579-581第一組第二組第三組第四組第五組.豬赤痢 病原:Brachyspira hyodysenteriae 下痢糞便中夾帶粘膜及鮮血 死亡率較高 螺旋體結腸炎 病原:Brachyspira pilosicoli 下痢帶粘膜，但不帶血 腸道沙門氏桿菌 病原:傷寒沙門氏桿菌 水痢 發高熱 死亡率高 鞭蟲 腸扭轉 胃潰瘍 黴菌毒素 慢性傳染性胃腸炎.屠宰後以腸壁變厚作為判斷標準 無特異性 敏感性低(容易低估真正感染比率).死後豬隻採腸
7、道組織進行Warthin Starry鍍銀法或Hematoxylin Eosin染色法.以拉森菌存在與否決定 高特異性(100%)低敏感性(39%)活體動物亦可進行(糞便)極少量菌體即可測得，但感染豬隻必須在排毒期方可測得，所以測得結果僅能針對單一豬隻，無法判斷全場感染狀況 成本昂貴.利用免疫螢光抗體法檢測感染(曾感染)豬隻的IgG抗體 最新研發科技 高持異性91%高敏感性97%好處 可知全場疾病感染動向,進而可進行治療或控制 成本低廉 一般實驗室即可進行.陽性比率豬場%.屠宰時以PCR檢查.飼養管理全進全出強力清潔及消毒(使用非氛類消毒劑)檢測外來的後備母豬避免應激因子,包括 密飼,通風不良
8、,溫差太大*Bane y col.Proc.15 IPVS Congress,1998.含藥飼料添加物選擇有效的抗生素藥物敏感性高(MIC值低)可以進入腸道細胞並在細胞中蓄積進入細胞後仍能保持藥物活性.拉森菌附著在腸道上皮細胞表面,2小時鑽入細胞內後穿透進入上皮細胞阻斷拉森菌的核醣體作用xxx腸道上皮細胞拉森菌x潛伏期二週.預防高爆發期或預期應激出現時開始投藥每噸飼料投予100克泰農,連續投予21天之後21天每噸飼料投予40克泰農之後至上巿為止每噸飼料投予20克泰農 控制出現臨床症狀即開始在每噸飼料中投予100克泰農,連續投予21天之後21天每噸飼料投予40克泰農之後至上巿為止每噸飼料投予20
9、克泰農.帶原者?豬場的感染狀態?分娩時是否會排菌?保毒者?如何撲滅?免疫反應及疫苗?.Proliferation(thickening of the mucosa)Last 20 cm of the ileum-proximal colon.Mucosal foldings.Reticulated serosa.Secondary infections might form necrotic pseudomembranes.Up to 0.8 increase in FCR and 14 days more to slaughter.Winkelman,Proc.AASP,1987 From
10、1 to 6%increase in mortalityWard y Winkelman,Vet.Med.,1990 Clinical duration between 6 and 8 weeks and up to 15%cullsWinkelman,The compendium,1996McOrist,J.Comp.Pathol,1996.Ref:McOrist et al.,1997 Veterinary Record,140:579-581 Indirect effects of ileitisNegative impact on growth during a critical pe
11、riod for lean deposition(12-20 weeks)Changes the fat/lean ratio,devaluating the value of the carcass.(increase in back fat).%39 farmsAGE weeks.%Age weeks19 Companies,500-8000 Sows each one,120 samples by company/20 samples each group of age.Age weeks%Positivesamples20 blood samples each group of age
12、 for Ileitest20 fecal samples each group of age for PCR.S/P.727S/P1.915S/P1.024S/P1.708S/P1.294S/P1.123-Viremia of PRRS,destabilization-Increase(+)to Lawsonia but without clinical signs Pigs stabilize to PRRS-Increase pigs%(+)to LawsoniaIleitis cause:-clinical signs-Lesion%Age weeks.%Age weeksS/P1.3
13、67S/P0.870S/P1.3S/P1.645S/P1.639S/P1.433.S/P0.667S/P2.64S/P1.942S/P1.744S/P1.706%Age weeks.%Age weeks.To understand who Lawsonia is moving in the farm To get the correlation with clinical signs Is important to know which others diseases there are at the farm To know which others disease increase the
14、 dissemination of Lawsonia and the economical impact of Ileitis .Orally inoculated pigs using L.intracellularis Dose:1.0 X 108 to 8.0 X 108 organisms Diarrhea began 2 weeks post challenge persisted 1-2 weeks Not necessary all the pigs sick show diarrhea.Excretion during weeks 2 to 10 after the chall
15、enge in 20-50%of the pigs Some of the pig shed 7.0 X 108 organisms/gram of feces Study suggests one infected pig may shed enough to infect others Disease may persist in few who infect others The effect on the ADG is from 3 to 9 weeks after inoculateSmith&McOrist.Res Vet Sci.1997;62(1):6-10.Ref:McOri
16、st et al.,1997 Veterinary Record,140:579-581 Ileitis may cost from US$1.48 to US$22.19 per affected pig,depending on disease severity,duration,feed convertion mortality and numer of culled pigs Indirect effects of ileitisNegative impact on growth during a critical period for lean deposition(12-20 we
17、eks)Changes the fat/lean ratio,devaluating the value of the carcass.(increase in back fat).Diagnosis Disease (Ileitest/IFA,PCR,Histophatology)Disease form(subclinic,chronic,hemorrhagyc)Control risk factors Serologic profile Ileitest to understand the correlation with clinical signs Strategic medicat
18、ion program According to Ileitest and clinical signs Control other disease Salmonella,PRDC,PRRS,etc.Reduce stress associated to movement.Decrease mixing.Reduce vicious environment:Incorrect ventilation.Temperature fluctuation.Avoid overcrowding.Adequate feeder space and water flow.High quality diets
19、.Control of other diseases.According to Ileitest and clinical signs.Use of intracelular activity antibiotic.Tylan 110 ppm weeks 16 to 18S/P.437S/P.202S/P.718S/P1.708S/P1.294S/P1.123.%Tylan 110 ppm weeks 6-9.Acute haemorrhagic form:Replacement gilts:Tylan*110 ppm at least 3 weeks.Grower and Finisher:
20、70kg.to Market,use 110 ppm,Tylan*(control and prevention)Note:The dose in mg/kg bw with Tylan*for control of Ileitis is 3-5 mg/ke bw with 110 ppm,for this reason in the case of gilt and sows is necessary to review the feed intake to adjust the dose according to consumption.Subclinical presentation:1
21、2 to 25 kg.,use 110 ppm,Tylan*(prevention and control).25 to 60 kg.,use 44 ppm,Tylan*(maintenance).60 kg.to Market,use 22 ppm,Tylan*to reduce the lightweight pigs to slaughter.Chronic presentation:25 to 40 kg.,use tylosin 110 ppm for prevention and control of ileitis40 to 60 kg.,use tylosin 44 ppm t
22、o maintain health status of the gut.60 kg.to Market,use tylosin 22 ppm to reduce lightweight pigs to market.Ileitis is world wile disease It has a important economic impact The presentation in each farm is different IleiTest help us to understand the dynamic of Ileitis We need to understand the mixed diseases at the farm,for a better control Tylan*is a good tool for control and prevention.
