| 摘要: | 本試驗利用可表現瘤胃細菌Ruminococcus albus 7之細菌素的酵母菌(Saccharomyces cerevisiae)，研究其在作為抗生素替代物與雞隻飼糧添加劑之效果，分為肉雞與蛋雞試驗兩部分進行。
第一部份以體外發酵及肉雞餵飼試驗來評估抗生素及含細菌素酵母菌對於白肉雞生理況狀之影響。試驗飼糧為(1)空白組、(2)添加含細菌素酵母菌(0.25%)及(3)添加六肽黴素(2.5ppm)三組，體外發酵試驗分別於飼養3週齡和5週齡時，以空白組雞隻之盲腸內容物及糞便為接種原，測量24小時內產氣表現及發酵產物濃度。飼養試驗中，雞隻於3週齡和5週齡分析其血液生化值與糞便菌相，同時犧牲雞隻後收集盲腸內容物，分析其脂肪酸組成與氨濃度。體外發酵試驗中，添加六肽黴素與細菌素會提高發酵液中之丙酸濃度，而產氣表現方面各處理組無明顯差異，但盲腸與糞便接種之體外產氣表現具有高度相關性。飼養試驗結果顯示，添加含細菌素酵母菌於肉雞飼糧中，會增加飼養後期(5週齡)血液中尿酸的濃度，但會降低血中之膽固醇(降低約18%)(P<0.05)。菌相分析顯示，飼養前期(3週齡)添加細菌素可降低糞便菌相中沙門氏桿菌(Salmonella)之數目(P<0.05)，飼養後期(5週齡)添加細菌素可降低沙門氏桿菌(Salmonella)與大腸桿菌群(Coliform)之數目(P<0.05)，並且增加乳酸菌(P<0.05)之菌數。藉由血液生化與菌相分析，配合發酵產物變化結果，可發現抗生素及含細菌素酵母菌對肉雞腸道菌相與盲腸揮發性脂肪酸有部分類似之影響效果，而添加細菌素更可降低血液中膽固醇濃度。
第二部分以含細菌素之酵母菌添加於白色來航蛋雞飼糧中，藉由長期產蛋試驗，評估細菌素對於蛋雞生理況狀與生產表現之影響。試驗飼糧分為(1)空白組、(2)酵母菌控制組(0.25%)、(3)細菌素酵母菌(0.125%)、(4)細菌素酵母菌(0.25%)及(5)細菌素酵母菌(0.5%)五組。酵母菌與細菌素自蛋雞26週齡起開始添加，每四週採樣一次。血液生化樣品由翼靜脈採集，並以肛門拭子採集糞便樣品進行菌相分析，每日記錄蛋雞產蛋狀況，採血時同時收集新鮮雞蛋測量蛋品質性狀。試驗結果顯示，添加含細菌素酵母菌於蛋雞飼糧中，可降低血液中乳酸、膽固醇的濃度與AST(aspartate aminotransferase)的活性，低濃度添加組(<0.25%)可降低ALP(alkaline phosphatase)之活性。蛋品質表現方面，含細菌素酵母菌可以增加蛋黃重量與蛋殼強度，但不影響產蛋表現，低濃度添加組(0.125%)可降低蛋黃總膽固醇之濃度。蛋黃脂肪酸組成上，添加0.25%會有較低比例的C16:0和C18:0。糞便菌相分析顯示，添加細菌素可以提高乳酸菌(Lactobacillus)之數目，持續添加8~12週後可以降低糞便中沙門氏菌(Salmonella)與大腸桿菌(Escherichia coli)之數目。藉由血液生化與菌相分析，配合蛋雞生產表現與蛋品質變化結果，添加0.25%含細菌素酵母菌對於蛋雞生理狀況、糞便菌相與生產表現有最佳之效果。
The purpose of this study was to evaluate the effect of yeast with bacteriocin from Ruminococcus albus 7 on physiological state and production performance of broilers and hens.
The broilers experiment were divided into treatments including (1) control, (2) yeast with bacteriocin (0.25%)[B], and (3) nosiheptide (2.5 ppm)[N]. The in vitro fermentation experiment was tested at the 3 and 5 week old by inoculating fecal and cecal content collected from control group. The gas production and fermentation product concentration were measured after 24 hr incubation. In broiler feeding experiments, clinic chemistry parameters and fecal flora test were assay at the third and fifth week. Broilers were slaughtered at the same age to get ceca content samples for volatility fatty acid composition and ammonia concentration assay. Both [B] and [N] treatments resulted in higher propionicacid concentration in fermentation broth. The gas production models showed high correlation between fecal and cecal inoculating samples, but no significant differences among all treatments. The clinic chemistry parameters indicated that addition of yeast with bacteriocin increased the blood uric acid at the 5 weeks old, but it decreased cholesterol concentration (about 18%)(P<0.05). The fecal flora results indicated that addition of yeast with bacteriocin decreased Salmonella(P<0.05) counts at 3 weeks old, the Salmonell and Coliform counts also decreased at 5 weeks old(P<0.05). However, the Lactobacillus counts were increased when yeast with bacteriocin added in diet. According to the data from clinic chemistry, fecal flora and fermentation performance, it showed that antibiotic and bacteriocin had similar effect on cecal fermentation product. Nevertheless, bacteriocins addition could reduce blood cholesterol level of broilers.
In the laying hen experiment, animals were assigned into five groups including (1) control group, (2) yeast control (0.25%), (3) yeast with bacteriocin (0.125%), (4) yeast with bacteriocin (0.25%) and (5) yeast with bacteriocin (0.5%). All supplements were added to the experimental diets of the hens from 26 to 46 weeks old. Samples were collected every four weeks. Blood samples were collected from the wing vein for clinic chemistry assay and fecal samples were collected by swab for the flora test. The egg production performance was recorded daily and fresh eggs were collected for quality test. The clinic chemistry result indicated that the addition of yeast with bacteriocin decreased the AST (aspartate-aminotransferase) activity and cholesterol concentration in laying hen blood. The result of egg quality indicated that bacteriocin increased the mass of yolk and the strength of eggshell, but it had no effect on the performance of egg production. Low concentration (0.125%) of bacteriocin addition could decrease total yolk cholesterol, addition of 0.25% bacteriocinin diet could decrease the proportion of C16: 0andC18: 0 in egg yolk fatty acid composition. The fecal flora result indicated that the addition of bacteriocin increased the Lactobacillus counts. After supplement bacteriocin for 8 to 12 weeks, the Salmonella and Escherichia coli counts were also decreased. Combined the data from clinic chemistry, fecal flora, egg production and egg quality, the 0.25% yeast with bacteriocin addition may result in the best physiological parameter and egg production performance of laying hen. |
