Blanco-Fuertes Miguel, Sibila Marina, Franzo Giovanni, Obregon-Gutierrez Pau, Illas Francesc, Correa-Fiz Florencia, Aragón Virginia
Centre de Recerca en Sanitat Animal (CReSA), Unitat Mixta d'Investigació IRTA-UAB en Sanitat Animal, Campus de la Universitat Autònoma de Barcelona (UAB), 08193, Bellaterra, Barcelona, Spain.
IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193, Bellaterra, Barcelona, Spain.
Anim Microbiome. 2023 Oct 20;5(1):53. doi: 10.1186/s42523-023-00275-3.
The nasal microbiota of the piglet is a reservoir for opportunistic pathogens that can cause polyserositis, such as Glaesserella parasuis, Mycoplasma hyorhinis or Streptococcus suis. Antibiotic treatment is a strategy to control these diseases, but it has a detrimental effect on the microbiota. We followed the piglets of 60 sows from birth to 8 weeks of age, to study the effect of ceftiofur on the nasal microbiota and the colonization by pathogens when the treatment was administered to sows or their litters. We also aimed to revert the effect of the antibiotic on the nasal microbiota by the inoculation at birth of nasal colonizers selected from healthy piglets. Nasal swabs were collected at birth, and at 7, 15, 21 and 49 days of age, and were used for pathogen detection by PCR and bacterial culture, 16S rRNA amplicon sequencing and whole shotgun metagenomics. Weights, clinical signs and production parameters were also recorded during the study.
The composition of the nasal microbiota of piglets changed over time, with a clear increment of Clostridiales at the end of nursery. The administration of ceftiofur induced an unexpected temporary increase in alpha diversity at day 7 mainly due to colonization by environmental taxa. Ceftiofur had a longer impact on the nasal microbiota of piglets when administered to their sows before farrowing than directly to them. This effect was partially reverted by the inoculation of nasal colonizers to newborn piglets and was accompanied by a reduction in the number of animals showing clinical signs (mainly lameness). Both interventions altered the colonization pattern of different strains of the above pathogens. In addition, the prevalence of resistance genes increased over time in all the groups but was significantly higher at weaning when the antibiotic was administered to the sows. Also, ceftiofur treatment induced the selection of more beta-lactams resistance genes when it was administered directly to the piglets.
This study shed light on the effect of the ceftiofur treatment on the piglet nasal microbiota over time and demonstrated for the first time the possibility of modifying the piglets' nasal microbiota by inoculating natural colonizers of the upper respiratory tract.
仔猪鼻腔微生物群是机会性病原菌的储存库，这些病原菌可导致多发性浆膜炎，如副猪嗜血杆菌、猪鼻支原体或猪链球菌。抗生素治疗是控制这些疾病的一种策略，但它对微生物群有不利影响。我们跟踪了60头母猪的仔猪从出生到8周龄的情况，以研究头孢噻呋对鼻腔微生物群的影响以及在对母猪或其仔猪进行治疗时病原菌的定植情况。我们还旨在通过接种从健康仔猪中选出的鼻腔定植菌来逆转抗生素对鼻腔微生物群的影响。在出生时以及7、15、21和49日龄采集鼻拭子，用于通过PCR和细菌培养、16S rRNA扩增子测序和全基因组鸟枪法宏基因组学进行病原菌检测。在研究期间还记录了体重、临床症状和生产参数。
仔猪鼻腔微生物群的组成随时间变化，在保育期末梭菌目明显增加。头孢噻呋的使用在第7天意外地导致α多样性暂时增加，主要是由于环境分类群的定植。与直接给仔猪使用相比，在分娩前给母猪使用头孢噻呋对仔猪鼻腔微生物群的影响持续时间更长。通过给新生仔猪接种鼻腔定植菌，这种影响部分得到逆转，同时出现临床症状（主要是跛行）的动物数量减少。两种干预措施都改变了上述病原菌不同菌株的定植模式。此外，所有组中耐药基因的流行率随时间增加，但在给母猪使用抗生素时断奶时显著更高。而且，当直接给仔猪使用头孢噻呋治疗时，诱导选择了更多的β-内酰胺耐药基因。
本研究揭示了头孢噻呋治疗随时间对仔猪鼻腔微生物群的影响，并首次证明了通过接种上呼吸道天然定植菌来改变仔猪鼻腔微生物群的可能性。
