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The objective of this study was to evaluate the prevalence and characteristics of avian-origin mcr -1-harbouring Escherichia coli in Shandong Province, China. During 2017—2018, a total of 668 non-duplicate E. coli isolates were separately collected from 8eight large intensive poultry farms in Shandong Province. Antimicrobial susceptibility testing for 10 antimicrobial agents commonly used in farms was performed on all E. coli isolates by the agar dilution method; the mobile colistin resistance gene (mcr -1) gene was screened by PCR, and mcr -1 positive isolates were PCR-screened for antimicrobial resistance genes and typed by multi-locus sequence typing (MLST). Among the 668 E. coli , 102 (15.3%) harbored the mcr -1 gene; high antimicrobial resistance rates were observed for ampicillin (100/102, 98.0%), followed by amoxicillin (99/102, 97.1%) and florfenicol (97/102, 95.1%), and a low level of resistance was found for amoxicillin/clavulanic acid (24/102, 23.5%). Five ESBL genes were detected, and all isolates carried bla TEM (102/102, 100%), followed by bla CTX–M (90/102, 88.2%). Four PMQR genes were detected; aac(6)-Ib-cr (40/102, 39.2%) was the most commonly isolated PMQR gene, followed by qnrA (10/102, 9.8%). Thirty-eight different kinds of STs were identified, and the dominant ST was ST93 (19/102, 18.6%), followed by ST48 (9/102, 8.8%). In summary, E. coli from poultry in Shandong could be a reservoir for the mcr -1 gene, which could pose serious risks to human public health. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus (S. aureus) is one of the most common pathogens that cause mastitis in dairy cows. The emergence of methicillin-resistant S. aureus (MRSA) constitutes a serious public health concern due to its ability to colonize and infect humans and animals. In this study, the prevalence and antimicrobial resistance of S. aureus and MRSA were investigated from bulk tank milk (BTM) in Shandong dairy farms. A total of 418 pooled BTM samples from 418 different dairy farms were collected. The prevalence of S. aureus was 28.9% (121/418), while the MRSA prevalence was 0.7% (3/418). The strains exhibited high percentages of resistance to penicillin (74.4%) and erythromycin (58.7%), and 91.7% of the isolates were found to be resistant to at least one antimicrobial agent. Moreover, 55.4% (67/121) of isolates were multidrug-resistant (MDR). The most predominant virulence genes were sed (13.2%, 16/121) and sec (8.3%, 10/121), which encode Staphylococcal enterotoxins (sed and sec). Multilocus sequence typing (MLST) was employed to identify 18 different sequence types (STs). The predominant STs were ST50 (13.2%, 16/121) and ST398 (12.4%, 15/121), while ST97, ST2779, and ST3191 were observed in MRSA isolates. Staphylococcal protein A gene (spa) typing identified spa types t034 (12.4%, 15/121) and t189 (9.9%, 12/121) most frequently among S. aureus isolates, while t002, t267, and t437 were observed in MRSA isolates. The results of this study indicated that S. aureus isolates had a relatively high prevalence rate in BTM, and these isolates harbored multiple virulence and exhibited multiple antimicrobial resistance. Meanwhile, our results confirm the lurking threat of MRSA in raw milk and suggest the need for surveillance programs starting at the farm level. • The S. aureus from BTM showed high genetic diversity (spa, MLST). • Three MRSA isolates were identified from BTM. • MDR phenotype detected in 55.4% of the isolates from BTM. • Limited data about the prevalence and characterization of S. aureus , including MRSA, in BTM in China are available. [ABSTRACT FROM AUTHOR]

In this study, carbon emissions from agricultural energy consumption (CEAEC) are fully analyzed using data from the Yangtze River Economic Belt (YEB) between 2000 and 2017. First, generalized LMDI is adopted to decompose the drivers of CEAEC into five components. Then, the decoupling indicator and the decoupling effort indicator are constructed to quantify the decoupling degrees and examine the government's emission reduction efforts, respectively. The results show that (1) CEAEC in the YEB has shown a phased increase, reaching a peak at 1732.2510 4 t in 2012. Except for some decreases found in Shanghai, Chongqing, and Guizhou, it is shown that all provinces' CEAEC have risen to varying degrees. In contrast, the intensity of CEAEC in the YEB has been declining since 2005. (2) The economic output effect acts as the major contributor to the growth of CEAEC, followed by the population effect. In contrast, both the energy intensity effect and the energy structure effect are the primary reasons for reductions in CEAEC. The spatial difference in CEAEC in the YEB increased significantly from 2000 to 2017. (3) There was an alternating change from decoupling to coupling and then to negative decoupling from 2000 to 2017. Based on the conclusions mentioned above, it is proposed that the formulation of low-carbon agricultural development strategies should consider the structural adjustment of agricultural energy consumption and the advancements of agricultural technology., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)