Necrotic Enteritis
Necrotic Enteritis
壞死性腸炎（NE）是現代肉雞羊群中最常見和經濟上毀滅性的細菌疾病。NE爆發的早期跡象通常是濕窩和腹瀉以及死亡率的增加，這可能並不重要。然而，由於腸道損害以及隨後的消化和吸收，鳥類的生長速度和飼料效率的降低在第35天就變得明顯。由於這些因素，亞臨床感染在經濟上更具破壞性。此外，可能會發生由於與亞臨床NE相關的肝髒病變引起的加工時的譴責增加。臨床體征的嚴重程度隨鳥類的年齡而異。
Necrotic enteritis lesion scores (1-4)
NE is a complex, multifactorial disease with many unknown factors that influence its occurrence and the severity of outbreaks. In particular, sporadic outbreaks of NE can occur frequently in farms where antibiotics are not used as growth promoters, coccidial infections are not controlled, the husbandry practice is not strict, and diets based on viscous grains with animal protein sources.
快速增殖的誘發因素C.灌注NE的發作包括其他飲食和飼養因素，例如由於飲食配方的變化而導致的腸道粘膜損害或正常腸道微生物群的變化，例如包括高水平的粘性穀物的含量穀物和/或動物副產品，例如魚和肉粉。
What causes Necrotic Enteritis?
It is an infectious disease caused by產氣莢膜梭菌, which is a gram-positive, anaerobic bacterium that can be found in soil, litter, dust and at low levels in the intestine of healthy birds.產氣莢膜梭菌僅當NE從非毒素產生類型轉變為毒素產生類型時才引起NE。有五種類型C.灌注（A，B，C，D和E）產生許多毒素（Alpha，Beta，Epsilon，Iota和CPE）。澳门188bet网址據信α-毒素，一種酶（磷脂酶C），是NE發生的關鍵。但是，最近的一項研究表明，不產生α-毒素的分離株仍然會引起疾病，此外，最近在疾病中發現了一種稱為NETB的新毒素C.灌注分離物。
Prevention and treatment of Necrotic Enteritis
Poultry CRC Deputy CEO, Vivien Kite; Monash University PhD student, Anthony Keyburn; and Poultry CRC Chairman, Jeff Fairbrother at the Cooperative Research Centres Association (CRCA) Conference in Perth (May 2007)
Outbreaks of NE can be effectively prevented by including antibiotics such asbacitracin和阿維拉黴素在飼料中。此外，有效控製球粒感染可以大大降低NE爆發的風險。此外，如果在飼料中不使用抗生素，則嚴格的農場衛生管理實踐，對建築物的良好氣候控製以及仔細選擇用於飲食製定的飼料成分都對維持生產效率都很重要。在北歐國家，從飼料中除去抗生素，已經使用了離子性抗生素來管理NE。
Following the ground-breaking discovery that alpha-toxin is不是the main causative factor for NE, by a Monash University PhD student funded by the Poultry CRC, Anthony Keyburn, CSIRO Livestock Industries researchers have patented NetB, the toxin they believe is the causative agent. The research team has identified the novel toxin and is now working on how it might be used to create the first truly effective vaccines against NE.
Further information
- Choct, M. (2005). Australian Poultry CRC Fact Sheet: Necrotic Enteritis.
- Keyburn AL, Sheedy SA, Ford ME, Williamson MM, Awad MM, Rood JI, Moore RJ. Alpha-toxin of Clostridium perfringens is not an essential virulence factor in necrotic enteritis in chickens.Infect Immun.2006 Nov;74(11):6496-500. Epub 2006 Aug 21.
- Keyburn AL，Boyce JD，Vaz P，Bannam TL，Ford ME，Parker D，Di Rubbo A，Rood JI，Moore RJ。NETB，一種與由梭狀芽胞杆菌引起的禽壞死性腸炎有關的新型毒素。PLOS病原體。2008 Feb 8;4(2):e26.
- Branton，S。L.，Reece，F。N.＆Hagler Jr，W。M.（1987）。“小麥飲食對與壞死性腸炎有關的肉雞死亡率的影響。”188宝金博 ios下载家禽科學66，1326–1330。
- Hofacre, C. L., Froyman, R., Gautrias, B., George, B., Goodwin, M. A. & Brown, J. (1998). “Use of Aviguard and other intestinal bioproducts in experimental Clostridium perfringens-associated necrotizing enteritis in broiler chickens.”Avian Diseases42, 579–584.
- Kaldhusdal，M。＆Løvland，A。（2000）。“經濟影響產氣莢膜梭菌is greater than anticipated.”世界家禽188宝金博 ios下载16, 50–51.
- Kaldhusdal，M。＆Skjerve，E。（1996）。“飲食中穀物含量與挪威肉雞雞的壞死性腸炎發生率之間的關聯。”Preventive Veterinary Medicine 28, 1–16.
- 教區，W。E。（1961）。“家禽中的壞死腸炎（Gallus gallus fimderus）。I.疾病的組織病理學和菌株的分離梭子座韋爾奇.”Journal of Comparative Pathology71，377–393。
- Riddell, C. & Kong, X. M. (1992). “The influence of diet on necrotic enteritis in broiler chickens.”Avian Diseases36, 499–503.
- Truscott, R. B. & Al-Sheikhly, F. (1977). “Reproduction and treatment of necrotic enteritis in broilers.”美國獸醫研究雜誌38, 857–861.
- van der Sluis, W. (2000a). “Necrotic enteritis (1): Clostridial enteritis a syndrome emerging worldwide.”世界家禽188宝金博 ios下载16, 56–57.
- Van der Sluis，W。（2000b）。“壞死性腸炎（3）：梭菌腸炎通常是一個被低估的問題。”世界家禽188宝金博 ios下载16, 42–43.
