日糧指示劑對育肥豬糞中微生物、揮發性脂肪酸VFA、營養物質消化率和生長性能的影響

畜牧編輯

　　2015. J. Anim. Sci. 93: 2183-2190

　　日糧指示劑對育肥豬糞中微生物、揮發性脂肪酸VFA、營養物質消化率和生長性能的影響

　　B. J. Kerr, T. E. Weber and C. J. Ziemer

　　在測定動物食糜通過速率和營養物質消化率的試驗中通常使用指示劑，如三氧化二鉻、氧化鐵、二氧化鈦。然而，這些指示劑對糞中微生物區系以及VFA產量的影響還未知。本文通過兩個動物試驗，共計72頭單欄飼喂的育肥豬，研究了日糧指示劑對糞中微生物區系、糞氨和VFA濃度、營養物質消化率和生長性能的影響。試驗日糧分為四組，無指示劑組、0.5% Cr2O3、0.5%Fe2O3、0.5%TiO2組。在試驗一中，飼喂33天后，收集新鮮糞便測定微生物區系、糞氨和VFA濃度、營養物質消化率和動物生長性能。試驗處理對糞中總菌落數和細菌總數無顯著影響。但是與對照組相比，飼喂氧化鐵日糧豬只糞中古生菌有降低的趨勢（P=0.07）。飼喂指示劑（Cr2O3、Fe2O3和TiO2）日糧可以提高糞中細菌豐度（P=0.03、0.01和0.10），但是卻對糞中微生物菌落的均勻性和多樣性指數沒有影響。變性梯度凝膠電泳分析表明指示劑不會對電泳條帶產生影響。不同指示劑對糞中干物質、氨氣濃度和VFA濃度產生影響。與對照組相比，飼喂三氧化二鉻日糧的豬只對鈣、銅、鐵和磷的消化率更高（P≤0.02），但是鈦消化率降低（P=0.08）。飼喂氧化鐵日糧的豬只對鈣的消化率更高（P=0.08），但是對鈦的消化率更低（P=0.01）。飼喂氧化鈦日糧的豬只對鐵和鋅的消化率更高（P≤0.09），但是鈦消化率降低（P=0.01）。在試驗二中，日糧指示劑對豬只生長性能無影響。總之，試驗結果表明，日糧中添加三氧化二鉻、氧化鐵和氧化鈦對微生物區系、糞氨、VFA濃度、營養物質消化率的影響非常小，表明其適用于消化試驗。

　　Dietary marker effects on fecal microbial ecology, fecal VFA, nutrient digestibility coefficients, and growth performance in finishing pigs

　　B. J. Kerr, T. E. Weber and C. J. Ziemer

　　Use of indigestible markers such as Cr2O3, Fe2O3, and TiO2 are commonly used in animal studies to evaluate digesta rate of passage and nutrient digestibility. Yet, the potential impact of indigestible markers on fecal microbial ecology and subsequent VFA generation is not known. Two experiments utilizing a total of 72 individually fed finishing pigs were conducted to describe the impact of dietary markers on fecal microbial ecology, fecal ammonia and VFA concentrations, nutrient digestibility, and pig performance. All pigs were fed a common diet with no marker or with 0.5% Cr2O3, Fe2O3, or TiO2. In Exp. 1, after 33 d of feeding, fresh fecal samples were collected for evaluation of microbial ecology, fecal ammonia and VFA concentrations, and nutrient digestibility, along with measures of animal performance. No differences were noted in total microbes or bacterial counts in pig feces obtained from pigs fed the different dietary markers while Archaea counts were decreased (P = 0.07) in feces obtained from pigs fed the diet containing Fe2O3 compared to pigs fed the control diet. Feeding Cr2O3, Fe2O3, or TiO2 increased fecal bacterial richness (P = 0.03, 0.01, and 0.10; respectively) when compared to pigs fed diets containing no marker, but no dietary marker effects were noted on fecal microbial evenness or the Shannon-Wiener index. Analysis of denaturing gradient gel electrophoresis gels did not reveal band pattern alterations due to inclusion of dietary markers in pig diets. There was no effect of dietary marker on fecal DM, ammonia, or VFA concentrations. Pigs fed diets containing Cr2O3 had greater Ca, Cu, Fe, and P (P ≤ 0.02), but lower Ti (P = 0.08) digestibility compared to pigs fed the control diet. Pigs fed diets containing Fe2O3 had greater Ca (P = 0.08) but lower Ti (P = 0.01) digestibility compared to pigs fed the control diet. Pigs fed diets containing TiO2 had greater Fe and Zn (P ≤ 0.09), but lower Ti (P = 0.01) digestibility compared to pigs fed the control diet. In Exp. 2, no effect of dietary marker on pig performance was noted. Overall, the data indicate that the inclusion of Cr2O3, Fe2O3, or TiO2 as digestibility markers have little to no impact on microbial ecology, fecal ammonia or VFA concentrations, nutrient digestibility, or pig growth performance indicating they are suitable for use in digestion studies。

本文由上海亙泰企業提供，特此感謝！

山中的漫游者

腸道健康，腸道功能，要全面考慮，指示劑有沒有影響？是個實驗方法的首要考慮因素