Miller D N, Varel V H
U.S. Meat Animal Research Center, ARS, USDA, Clay Center, NE 68933-0166, USA.
J Anim Sci. 2003 Sep;81(9):2131-8. doi: 10.2527/2003.8192131x.
Odors from swine production facilities are associated with the storage and decomposition of manure. Diet is linked to manure composition and will likely affect odor, but the microbial mechanisms responsible for manure decomposition and odor production are poorly understood. To identify the sources of odor during manure fermentation, substrates (starch, casein, and cellulose) were added to slurries of fresh swine manure, and the anaerobic accumulation of fermentation products and the consumption of substrates were measured relative to no addition of substrates. Volatile fatty acids and alcohols were the dominant fermentation products in all treatments. The total VFA concentration from starch treatment was greater (P < 0.001) than for all other treatments. Branched-chain VFA and aromatic compounds accumulated in all treatments, but accumulation in the casein treatments was greater (P < 0.001) than in all other treatments. Thus, addition of carbohydrate to swine manure slurries did not circumvent protein fermentation, as was previously observed in cattle manure slurries. Based on substrate loss, starch and protein fermentation were equivalent in all treatments, with losses of each exceeding 4% of the DM. Substrate additions had a limited effect on the overall accumulation of odor compounds in manure and on odor compound composition. Compared with the results of the earlier fermentation study of fresh cattle manure, swine manure fermentation produced less lactate and more products of protein fermentation (branched-chain VFA and aromatic ring compounds). We hypothesize that differences in manure organic matter composition between cattle and swine, a result of diet and digestion, select for bacterial communities that are adapted to the available substrate composition.
养猪场的气味与粪便的储存和分解有关。日粮与粪便组成有关，可能会影响气味，但负责粪便分解和气味产生的微生物机制却知之甚少。为了确定粪便发酵过程中的气味来源，将底物（淀粉、酪蛋白和纤维素）添加到新鲜猪粪浆中，并相对于不添加底物的情况，测量发酵产物的厌氧积累和底物的消耗。挥发性脂肪酸和醇类是所有处理中的主要发酵产物。淀粉处理的总挥发性脂肪酸浓度高于所有其他处理（P < 0.001）。支链挥发性脂肪酸和芳香族化合物在所有处理中均有积累，但酪蛋白处理中的积累量高于所有其他处理（P < 0.001）。因此，向猪粪浆中添加碳水化合物并不能像之前在牛粪浆中观察到的那样避免蛋白质发酵。基于底物损失，所有处理中淀粉和蛋白质发酵相当，每种底物的损失均超过干物质的4%。底物添加对粪便中气味化合物的总体积累和气味化合物组成的影响有限。与早期新鲜牛粪发酵研究的结果相比，猪粪发酵产生的乳酸较少，蛋白质发酵产物（支链挥发性脂肪酸和芳香环化合物）较多。我们推测，由于日粮和消化的结果，牛和猪粪便有机质组成的差异选择了适应可用底物组成的细菌群落。
