Guerreiro Joana F, Pires Ana J, Nunes Mónica, Esteves Ana, Chambel Lélia, Pascoal Pedro, Pereira Marcelo, Fangueiro David, Tavares Luís, Dias Ricardo, Bexiga Ricardo, Oliveira Manuela
CIISA-Center for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal; Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal.
CIISA-Center for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal; Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal.
J Dairy Sci. 2025 Mar;108(3):2620-2631. doi: 10.3168/jds.2024-25616. Epub 2024 Dec 20.
The widespread use of recycled manure solids (RMS) as cow bedding material is not without risks, because cattle manure may act as a vehicle for pathogenic and antimicrobial-resistant bacteria dissemination. Thus, our aim was to evaluate RMS supplemented with a pine biochar produced in Portugal as a new cow bedding material, because the use of biochar has been shown to have the potential to mitigate the effect of relevant bacterial species when added to animal manure microbiota. Our experimental setup consisted on fresh RMS samples that were collected on a commercial dairy farm and placed in naturally-ventilated containers for a total of 4 groups: (1) nonsupplemented RMS, (2) RMS supplemented with 2.5% (wt/wt) of biochar, (3) RMS supplemented with 5% (wt/wt) of biochar, and (4) RMS supplemented with 10% (wt/wt) of biochar. Sampling was performed at 4 different incubation times (0, 5, 15, and 30 d) and in 2 distinct seasons: April through May (humid season) and June through July (dry season). The resulting 32 samples were subjected to DNA extraction and their microbiome profile determined through complete 16S rDNA gene sequencing using Nanopore next-generation sequencing. We observed that biochar supplementation clearly altered the microbiome of RMS, which was reflected in changes in populations' diversity and the relative abundance of relevant pathogenic bacteria. In particular, we found that long-term storage (30 d) was more beneficial than short-term storage, an effect that was more evident for samples supplemented with 2.5% or 5% biochar. In both seasons, those concentrations of biochar led to a decrease in the levels of several mastitis-causing agents (Enterobacteriaceae, streptococci, enterococci, and staphylococci). In addition, we also observed a reduction in the levels of Salmonella spp. and gram-positive bacilli in the biochar-supplemented samples. Unexpectedly, however, those same conditions yielded an increase in the abundance of Brucella spp., a group that includes important infectious agents, highlighting the need for a deeper evaluation of the effect of biochar supplementation of RMS to ensure the future safe and sustainable use of this environmentally-friendly resource in animal production.
将回收的粪便固体（RMS）广泛用作奶牛垫料并非没有风险，因为牛粪可能成为致病细菌和抗微生物细菌传播的媒介。因此，我们的目标是评估添加葡萄牙生产的松树生物炭的RMS作为一种新的奶牛垫料，因为研究表明，添加生物炭有可能减轻添加到动物粪便微生物群中相关细菌物种的影响。我们的实验设置包括在一个商业奶牛场收集新鲜的RMS样本，并将其放置在自然通风的容器中，共分为4组：（1）未添加生物炭的RMS；（2）添加2.5%（重量/重量）生物炭的RMS；（3）添加5%（重量/重量）生物炭的RMS；（4）添加10%（重量/重量）生物炭的RMS。在4个不同的孵育时间（0、5、15和30天）以及2个不同的季节（4月至5月，潮湿季节；6月至7月，干燥季节）进行采样。对得到的32个样本进行DNA提取，并使用纳米孔下一代测序通过完整的16S rDNA基因测序确定其微生物群落特征。我们观察到，添加生物炭明显改变了RMS的微生物群落，这反映在种群多样性的变化以及相关致病细菌的相对丰度上。特别是，我们发现长期储存（30天）比短期储存更有益，这种效果在添加2.5%或5%生物炭的样本中更为明显。在两个季节中，这些生物炭浓度都导致了几种引起乳腺炎的病原体（肠杆菌科、链球菌、肠球菌和葡萄球菌）水平的下降。此外，我们还观察到添加生物炭的样本中沙门氏菌属和革兰氏阳性杆菌的水平有所降低。然而，出乎意料的是，相同的条件导致了布鲁氏菌属丰度的增加，布鲁氏菌属包括重要的传染原，这突出表明需要对添加生物炭的RMS的效果进行更深入的评估，以确保这种环境友好型资源在动物生产中的未来安全和可持续利用。
