Duarte Andrea Camacho, Durmic Zoey, Vercoe Philip E, Chaves Alexandre V
The University of Sydney, Faculty of Science, School of Life and Environmental Sciences, Sydney, NSW Australia.
The University of Western Australia, School of Agriculture and Environment', Crawley, WA, Australia.
Anaerobe. 2017 Dec;48:59-65. doi: 10.1016/j.anaerobe.2017.06.013. Epub 2017 Jun 28.
The effect of increasing the concentration of commercial pequi (Caryocar brasiliense) oil on fermentation characteristics and abundance of methanogens and fibrolityc bacteria was evaluated using the rumen simulation technique (Rusitec). In vitro incubation was performed over 15 days using a basal diet consisting of ryegrass, maize silage and concentrate in equal proportions. Treatments consisted of control diet (no pequi oil inclusion, 0 g/kg DM), pequi dose 1 (45 g/kg DM), and pequi dose 2 (91 g/kg DM). After a 7 day adaptation period, samples for fermentation parameters (total gas, methane, and VFA production) were taken on a daily basis. Quantitative real time PCR (q-PCR) was used to evaluate the abundance of the main rumen cellulolytic bacteria, as well as abundance of methanogens. Supplementation with pequi oil did not reduce overall methane production (P = 0.97), however a tendency (P = 0.06) to decrease proportion of methane in overall microbial gas was observed. Increasing addition of pequi oil was associated with a linear decrease (P < 0.01) in dry matter disappearance of maize silage. The abundance of total methanogens was unchanged by the addition of pequi oil, but numbers of those belonging to Methanomassiliicoccaceae decreased in liquid-associated microbes (LAM) samples (P < 0.01) and solid-associated microbes (SAM) samples (P = 0.09) respectively, while Methanobrevibacter spp. increased (P < 0.01) only in SAM samples. Fibrobacter succinogenes decreased (P < 0.01) in both LAM and SAM samples when substrates were supplemented with pequi oil. In conclusion, pequi oil was ineffective in mitigating methane emissions and had some adverse effects on digestibility and selected fibrolytic bacteria.
使用瘤胃模拟技术（Rusitec）评估了增加商业巴西坚果（Caryocar brasiliense）油浓度对发酵特性以及产甲烷菌和纤维分解菌数量的影响。体外培养在15天内进行，基础日粮由黑麦草、玉米青贮和精料按等比例组成。处理组包括对照日粮（不添加巴西坚果油，0 g/kg干物质）、巴西坚果剂量1（45 g/kg干物质）和巴西坚果剂量2（91 g/kg干物质）。经过7天的适应期后，每天采集发酵参数（总气体、甲烷和挥发性脂肪酸产量）样本。采用定量实时PCR（q-PCR）评估主要瘤胃纤维分解菌的数量以及产甲烷菌的数量。添加巴西坚果油并未降低总体甲烷产量（P = 0.97），然而观察到总体微生物气体中甲烷比例有下降趋势（P = 0.06）。巴西坚果油添加量的增加与玉米青贮干物质消失率的线性下降相关（P < 0.01）。添加巴西坚果油后，总产甲烷菌数量未变，但属于甲烷微球菌科的产甲烷菌数量在液体相关微生物（LAM）样本（P < 0.01）和固体相关微生物（SAM）样本（P = 0.09）中分别减少，而仅在SAM样本中，短柄产甲烷杆菌数量增加（P < 0.01）。当底物添加巴西坚果油时，LAM和SAM样本中的琥珀酸纤维杆菌数量均减少（P < 0.01）。总之，巴西坚果油在减轻甲烷排放方面无效，并且对消化率和某些纤维分解菌有一些不利影响。
