論文宣讀

      壞死性腸炎(necrotic enteritis, NE)是家禽常見的疾病之一，主要是由產氣莢膜梭菌 (Clostridium perfringens, CP) 引起，CP在腸道內過度增殖，觸發毒素大量產生，引起黏膜損傷，消化和吸收性能下降，造成家禽業者莫大的經濟損失。達臨床症狀時通常使用高劑量抗生素治療，而一般則以低劑量抗生素作為生長促進劑防治，但為避免抗藥性的問題，許多國家已禁止或限制使用抗生素作為生長促進劑，因此需另尋治療NE的方法。奈米矽片 (nanosilicate platelet, NSP) 是將蒙脫石(Montmorillonite)的層狀結構經過處理後，分開生成奈米級矽酸鹽薄片，因其含大量負電荷、表面積大且離子電荷強，容易吸引金屬離子與極性有機分子，並貼附於生物細胞表面，因此比蒙脫石更具有抗菌活性；另外，先前研究顯示，當NSP作為抗菌金屬之載體時，可降低金屬在動物體內累積的毒性，並保有抗菌之效果。牛至 (Origanum vulgare) 是一種香草植物，其主要成分為百里酚 (carvacrol) 及香芹酚 (thymol)，兩者協同作用使牛至精油(oregano essential oil, OEO) 具有抗菌、抗真菌、抗病毒、抗寄生蟲等特性。因此本研究目的是測試飼糧中添加NSP及OEO複方對感染CP白肉雞之影響。試驗將Ross 308白肉雞分為對照組 (CON)、C. perfringens感染對照組 (CP)、0.1% NSP+CP (NP)、0.1% OEO+CP (OE)、0.1% NSP + OEO (1 : 5)+CP (NOL)、或0.1% NSP + OEO (1 : 10)+CP (NOH)，共六組，在第18、20天灌食2 x10⁸ cfu/ml之C. perfringens，餵飼試驗5週。期間每週秤量體重以及採食量，計算其飼料轉換率；於3~4週翼靜脈採血，分析血漿中IL－1β含量；於第4週時，進行腸道組織採樣，分析腸道中抗菌蛋白的表現量及緊密連結蛋白含量，並記錄腸道病變評分及觀察腸道切片組織形態；另外，在腸道屏障部分以灌食FITC (Fluorescein isothiocyanate) 檢測腸道通透性。結果顯示，CP組與對照組相比，在實驗前期 (D1-21) 與全期 (D1-35) 對生長性狀有負面影響；另外，在前期NOH組之採食量較NOL組差，而在全期NOH組之FCR顯著優於CP及其他處理組。腸道病變評分結果顯示，CP組之評分顯著高於對照組，而其他處理組與CP 組相比則無顯著差異。在腸道形態的部分，CP組在空腸之絨毛長度較對照組短，而NOH及OE組在空腸之隱窩深度較CP組深，在絨毛長度與隱窩深度比值方面，則是NSP組顯著高於CP及NOL組。腸道通透性分析結果顯示，處理組與CP組相比，皆改善了腸道通透性，尤其NOL組效果更加明顯。腸道抗菌蛋白分析結果顯示，感染CP會降低抗菌蛋白之表達量，在空腸NOL可改善AvBD 1及AvBD 8之表達量，NP則改善CATHL 3表達量；而在迴腸，OE改善AvBD 1及AvBD 8之表達量，NP改善CATHL 3表達量，而NOL則增加Mucin 2之表達量。綜上所述，飼糧中添加NSP、OEO和兩者之混合物時，可改善CP對雞隻腸道之負面影響。

關鍵字：白肉雞、產氣莢膜梭菌、奈米矽片、牛至精油、抗發炎

• Abbes, S., J. B. Salah-Abbes, M. M. Hetta, M. Ibrahim, M. A. Abdel-Wahhab, H. Bacha, and R. Oueslati. 2008. Efficacy of Tunisian montmorillonite for in vitro aflatoxin binding and in vivo amelioration of physiological alterations. Appl. Clay Sci. 42: 151－157.
• Amany, A. E., M. G. Z. Amina, and H. M. G. El-Dein. 2021. Hepatoprotective role of clay and nanoclay for alleviating aflatoxin toxicity in male rats. Pak. J. Biol. Sci. 24: 1091－1102.
• Cooper, K. K., J. G. Songer, and F. A. Uzal. 2013. Diagnosing clostridial enteric disease in poultry. J. Vet. Diagn. Invest. 25: 314－327.
  Cui, H., C. Zhang, C. Li, and L. Lin. 2019. Antibacterial mechanism of oregano essential oil. Ind. Crops Prod. 139: 111498.
• Du, E., L. Gan, Z. Li, W. Wang, D. Lui, and Y. Guo. 2015. In vitro antibacterial activity of thymol and carvacrol and their effects on broiler chickens challenged with Clostridium perfringens. J. Anim. Sci. Biotechnol. 6: 58.
• Flores-Díaz, M., E. Barquero-Calvo, M. Ramírez, and A. Alape-Girón. 2016. Role of clostridium perfringens toxins in necrotic enteritis in poultry. Microbial Toxins 7: 119－134.
• Jin, X., G. Huang, Z. Luo, Y. Hu, and D. Liu. 2021. Oregano (Origanum vulgare L.) essential oil feed supplement protected broilers chickens against clostridium perfringens induced necrotic enteritis. Agriculture 12 : 18.
• Li, P. R., J. C. Wei, Y. F. Chiu, H. L. Su, F. C. Peng, and J. J. Lin. 2010. Evaluation on cytotoxicity and genotoxicity of the exfoliated silicate nanoclay. ACS Appl. Mater. Int. 2: 1608－1613.
• Liang, J. J., J. C. Wei, Y. L. Lee, S. H. Hsu, J. J. Lin, and Y. L. Lin. 2014. Surfactant－modified nanoclay exhibits an antiviral activity with high potency and broad spectrum. J. Virol. 88: 4218.
• Lin, J. J., W. C. Lin, S. D. Li, C. Y. Lin, and S. H. Hsu. 2013. Evaluation of the antibacterial activity and biocompatibility for silver nanoparticles immobilized on nano silicate platelets. ACS Appl. Mater. Interfaces 5: 433－443.
• Nadziakiewicza, M., S. Kehoe, and P. Micek. 2019. Physico-chemical properties of clay minerals and their use as a health promoting feed additive. Animals 9: 714.
• Shi, Y. H., Z. R. Xu, J. L. Feng, and C. Z. Wang. 2005. Efficacy of modified montmorillonite nanocomposite to reduce the toxicity of aflatoxin in broiler chicks. Anim. Feed Sci. Technol. 129:138－148.
• Shi, Y., Z. Xu, Y. Sun, C. Wang, and J. Feng. 2009. Effects of two different types of montmorillonite on growth performance and serum profiles of broiler chicks during aflatoxicosis. Turk. J. Vet. Anim. Sci. 33:15－20.
• Shojadoost, B., A. R. Vince, and J. F. Prescott. 2012. The successful experimental induction of necrotic enteritis in chickens by Clostridium perfringens: a critical review. BMC Vet. Res. 43: 74.
• Wei, J. C., Y. T. Yen, H. L. Su, and J. J. Lin. 2011. Inhibition of bacterial growth by the exfoliated clays and observation of physical capturing mechanism. J. Phys. Chem. C 115: 18770–18775.
• Yuan, C. W., J. T. Huang, C. C. Chen, P. C. Tang, J. W. Huang, J. J. Lin, S. Y. Huang, and S. E. Chen. 2017. Evaluation of efficacy and toxicity of exfoliated silicate nanoclays as a feed additive for fumonisin detoxification. J. Agric. Food Chem. 65: 6564－6571.