北臺灣白肉雞場污染沙門氏桿菌之風險因子分析暨全臺家禽場飼料之沙門氏桿菌污染調查

The identification of risk factors for Salmonella contamination in broiler farms in northern Taiwan and the survey for Salmonella contamination of poultry feeds in Taiwan

黃凰綺(Huang-Chi Huang)

指導教授 ： 蔡向榮

國立臺灣大學/獸醫專業學院/獸醫學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.01106

摘要

沙門氏桿菌是重要的人畜共通傳染病原，長久以來家禽被認為是媒介人類感染的主要來源之ㄧ，而白肉雞是消費量最大的肉雞品種，故其飼育過程之管控相當值得關注。為暸解北臺灣白肉雞場污染沙門氏桿菌之風險因子以作為禽場飼養管理之參考，進行以問卷調查及沙門氏桿菌檢測為基礎的病例對照研究，自2008年4月至2009年5月間共調查41個白肉雞場，包括14場開放式與27場水簾式雞場，於各場擇一雞舍調查。經前預備試驗後首度建立適用於北臺灣地區白肉雞場風險因子調查之研究方法，以連續3個時間點採樣並各採集雞隻臟器與飼料進行檢測。結果顯示場陽性率為56.1 % ，且雞場型態對於污染之影響未達顯著差異(p >0.05)，經分析得知有10個風險因子雖未達統計學顯著水準，但其勝算比值顯示可能與減少禽場污染有關，包括： (1)水簾式雞舍之型式為一層而非多層；(2)雞場入口具有需以鑰匙開啟之門鎖；(3)當雞隻飲水非自來水但先經處理過再使用；(4)定期清掃雞場內之犬貓糞便；(5)工作人員每天換洗工作服與工作鞋；(6)雞場具有圍牆與外界隔離；(7)進入雞舍前有一獨立之室內空間可供更換工作服與清潔雙手；(8)雛雞運送至雞舍時之容器非重複使用之塑膠籠；(9)雛雞來源為單一種雞場；(10)墊料使用前先移除發霉或結塊部份。另外，臺灣北部之氣候因子可能值得特別注意，本研究結果顯示禽場污染於涼季顯著提高(p <0.05)。 此外，有鑑於遭污染之家禽飼料可於禽場快速地傳播病原，故進行於家禽場進行之飼料採樣調查，並比較不同採樣點與6種培養基搭配組合之分離效果；檢測結果顯示沙門氏桿菌總分離率為7.6 % (59/778)、場陽性率21.4 % (33/154)；檢測件共涵括16種商業品牌，陽性檢體集中分離自5品牌。統計分析結果顯示： (1)不同飼料品牌之分離率呈顯著差異；(2)採樣點中最易取得之飼料槽檢體分離結果顯示，白肉雞飼料之分離率顯著高於其他禽種；(3)不分採樣點統計，種雞飼料之污染顯著高於其他飼料；(4)整體而言，禽場飼料分離沙門氏桿菌之培養基分離效果以RVS搭配XLD最佳，RVS搭配CAS居次 (p <0.05)。

關鍵字

沙門氏桿菌 ； 白肉雞 ； 風險因子 ； 勝算比 ； 飼料

並列摘要

Salmonella is an important pathogen in terms of zoonoses, poultry has been thought to be one of the major medium for human salmonellosis. Broiler chickens are one of the most commonly consumed chicken breed in Taiwan, therefore monitor it’s rearing and feeding conditions are very important. In order to alleviate the risk at commercial broiler chicken farms, a questionnaire based retrospective case-control study was conducted to identify risk factors with Salmonella contamination during the broiler rearing period. Forty-one broiler farms in northern Taiwan were studied from April 2008 to May 2009, included 14 open-sided and 27 wet pad cooling system housing type of chicken farms. All of the flock size was larger than 10,000 and only one house was studied in each farm. Through preliminary study, methods for the investigation of the broiler farms risk factor were established. Samples were taken at three consecutive time-points, visceral organs of chickens and feeds were also collected for further analysis. The results showed a flock positive rate of 56.1 % and the housing type of farms did not have a significant effect on Salmonella contamination (p >0.05). Through data analysis, odds ratios of ten risk factors indicated that thry may associate with the decrease in poultry farm contaminations although not statistically significant. These risk factors includes: (1) pad cooling system house which are single layered instead of multiple; (2) the entrance of the farm is locked; (3) none-tap drinking water for animals are pre-treated; (4) dog/cat feces are regularly cleaned in the farm; (5) workers outfits are changed and cleaned on a daily basis; (6) the farm is separated from the outside by a wall; (7) a single indoor room available for changing clothes and cleaning hands before entering the chicken house; (8) The cages used for transporting day-old chick are not reusable plastic cages; (9) a single source for day-old chick; (10) molds or coagulated litters are removed before use. Moreover, the weather factor of northern Taiwan is also worth mentioning, since contamination of Salmonella in broiler farms is significantly higher in colder seasons (p <0.05) .
Since contaminated poultry feeds may aid in the process of Salmonella spreading in poultry farms, an investigation of poultry feeds were also performed. Different sampling sites and isolation treatment methods were compared. The result shows a total Salmonella isolation rate to be 7.6 % (59/778), flock positive rate was 21.4 % (33/154). Feed samples included 16 different brands, Salmonella were isolated from five of the brands. The data analysis showed (1) isolation rate of different brands are significantly different; (2) isolation rate of feed troughts from broiler house showed a significantly higher isolation rate than from other types of poultry; (3) not taking sampling site into account, breeder chicken feeds have a higher contamination rate than other types of feeds; (4) Overall, the best culturing medium for Salmonella isolation from chicken feeds is to use RVS plus XLD. (p <0.05)。

並列關鍵字

Salmonella spp. ； salmonellae ； broiler ； risk factor ； odds ratio ； feed ； feedstuff

參考文獻

3. 行政院農業委員會。農業產銷工作手冊。臺北，臺灣；1994年:90。

8. 陳秀芬。以脈衝式電泳分析犬沙門氏桿菌之流行病學研究。碩士論文，屏東科技大學獸醫學系所，屏東，臺灣。2007。

76. Peng, C. F. (1992). Incidence and antimicrobial resistance of Salmonellae serotypes in southern Taiwan from 1978 through 1987. Gaoxiong Yi Xue Ke Xue Za Zhi 8, 247-254.

4. 李宗賢。臺灣沙門氏桿菌症的流行病學:由環境、食用豬畜產品到人。碩士論文，中興大學獸醫公共衛生學研究所，臺中，臺灣。2006。

5. 廖志偉。臺灣中部地區流浪犬及家犬沙門氏桿菌感染之研究。碩士論文，中興大學獸醫公共衛生學研究所，臺中，臺灣。2007。