Piva A, Panciroli A, Meola E, Formigoni A
Dipartimento di Morfofisiologia Veterinaria e Produzioni Animali, Faculty of Veterinary Medicine, University of Bologna, Italy.
J Nutr. 1996 Jan;126(1):280-9. doi: 10.1093/jn/126.1.280.
The study was conducted to determine if the response of swine cecal microflora to lactitol (beta-D-galactopyranosyl-(1-->4)-D-sorbitol; 3 mmol/L) varies when fermenting low (LF) or high fiber (HF) predigested diets. The inoculum was collected from four sows fitted with cecal cannulas, pooled, buffered and dispensed in 27 vessels under anaerobic conditions. The LF or HF predigested diets were used as substrate in two separate experiments. In each trial nine vessels were used as controls (C) without feed addition, nine received predigested feed (LF or HF) and the remaining nine vessels received the same amount of feed with the supplementation of lactitol (LF+L or HF+L). Lactitol (L) significantly lowered pH and the acetic to propionic acid ratio in the first 8 h of fermentation in both experiments (P < 0.05). At 4 and 8 h, the addition of lactitol reduced ammonia by 100 and 84% in LF+L and by 56 and 38% in HF+L (P < 0.05). In addition, LF+L and HF+L diets gave higher short-chain fatty acid energy yields by 70 and 40% than LF and HF, respectively (P < 0.05). Two bacterial growth models (logistic and Gompertz) were tested to fit gas production data. The Gompertz equation provided a better fit than the logistic model to gas production data for both LF and HF experiments. Lactitol reduced culture lag time in both experiments by approximately 50%, but it increased gas production rate and maximum gas production by approximately 60% only when the microflora was fermenting the LF predigested diet (P < 0.05). No difference in the duration of the exponential phase due to lactitol was observed in either experiment. Our results indicate that lactitol may be an interesting additive to animal feeding. It controlled harmful fermentation processes and stimulated short-chain fatty acid production to a greater extent in low than in high fiber diets, suggesting an improved fermentation of low fiber feed carbohydrates and eventually an increased availability of short-chain fatty acids for the host.
本研究旨在确定猪盲肠微生物群对乳糖醇（β-D-吡喃半乳糖基-(1→4)-D-山梨醇；3 mmol/L）的反应在发酵低纤维（LF）或高纤维（HF）预消化日粮时是否存在差异。接种物取自四只装有盲肠插管的母猪，混合后在厌氧条件下缓冲并分配到27个容器中。在两个独立的实验中，分别使用LF或HF预消化日粮作为底物。在每个试验中，九个容器用作不添加饲料的对照（C），九个容器接受预消化饲料（LF或HF），其余九个容器接受添加了乳糖醇的等量饲料（LF+L或HF+L）。在两个实验中，乳糖醇（L）在发酵的前8小时均显著降低了pH值和乙酸与丙酸的比例（P<0.05）。在4小时和8小时时，添加乳糖醇使LF+L组的氨减少了100%和84%，使HF+L组的氨减少了56%和38%（P<0.05）。此外，LF+L和HF+L日粮的短链脂肪酸能量产量分别比LF和HF高70%和40%（P<0.05）。测试了两种细菌生长模型（逻辑模型和Gompertz模型）以拟合产气数据。对于LF和HF实验，Gompertz方程比逻辑模型更能拟合产气数据。在两个实验中，乳糖醇均使培养延迟时间缩短了约50%，但仅当微生物群发酵LF预消化日粮时才使产气速率和最大产气量提高了约60%（P<0.05）。在任一实验中均未观察到乳糖醇对指数期持续时间的影响。我们的结果表明，乳糖醇可能是动物饲料中一种有趣的添加剂。它能控制有害发酵过程，并在低纤维日粮中比在高纤维日粮中更大程度地刺激短链脂肪酸的产生，这表明低纤维饲料碳水化合物的发酵得到改善，最终宿主可利用的短链脂肪酸增加。
