含水率和双乙酸钠对发酵全混合日粮青贮发酵品质和霉菌毒素的影响

Effects of moisture content and sodium diacetate on fermentation quality and mycotoxins of fermented total mixed ration

摘要:

为研究初始含水率和双乙酸钠添加水平对发酵全混合日粮(FTMR)青贮品质的影响。采用两因素完全随机试验设计，设 3 个含水率(50%、60%、65%)和 4 个双乙酸钠添加水平(0、0. 2%、0. 4%、 0. 8%)，发酵 35 d 对 FTMR 进行感官评定、常规成分、发酵参数以及霉菌毒素的测定。结果表明：含水率和双乙酸钠及其交互作用对 FTMR 有机酸生成有显著影响(P＜0. 05)；随含水率的升高，pH 值显著下降，乳酸和乙酸含量显著升高，粗蛋白、中性洗涤纤维、酸性洗涤纤维和霉菌毒素含量稍有下降，差异不显著(P＞0. 05)；添加双乙酸钠显著降低氨态氮/总氮和霉菌毒素含量(P＜0. 05)，添加 0. 2% 双乙酸钠的 pH 最低，粗蛋白和中性洗涤纤维含量较高。综上可知，适宜含水率、双乙酸钠及其互作能改善 FTMR 的发酵品质，减少干物质的损失，抑制霉菌毒素的大量繁殖。含水率为 60%，双乙酸钠添加量在 0. 2%~0. 4% 时，TMR 青贮发酵品质较佳。

Abstract:

The purpose of this study was to investigate the effects of initial moisture content and sodium diacetate on the quality of fermented total mixed ration(FTMR). Three moisture contents(50%，60%，65%)and four so- dium diacetate levels(0，0. 2%，0. 4%，0. 8%)were designed for a two-factor completely randomized trial. Sensory evaluation，conventional nutrient contents，fermentation parameters and mycotoxins of FTMR were analyzed 35 days after ermentation. The results showed that moisture content，sodium diacetate and their interactions had significant ef- fects on the formation of FTMR organic acid(P＜0. 05). With the increase of moisture content，pH value decreased significantly，and the content of lactic acid and acetic acid increased significantly. The crude protein，neutral deter- gent fiber，acid detergent fiber and mycotoxins decreased slightly，with no significant difference(P＞0. 05). The ad- dition of sodium diacetate significantly reduced the content of ammoniacal nitrogen/total nitrogen and mycotoxins(P ＜0. 05). The pH was the lowest with 0. 2% of sodium diacetate ，and the crude protein and neutral detergent fiber were higher. It can be concluded that appropriate moisture content and sodium diacetate can improve the fermentation quality of FTMR，reduce the loss of dry matter，and inhibit the proliferation of mycotoxins. Under the conditions of this study，60% moisture and 0. 2%~0. 4% sodium diacetate were the suitable combination to achieve the desired fermentation quality.