光照对畜禽粪便中抗生素降解和微生物的影响

为研究光照对粪便发酵降解抗生素的影响,采用固态发酵试验,对比避光和光照培养后不同猪鸡粪中主要残留抗生素浓度和细菌群落组成差异.结果表明,光照促进发酵后粪便的抗生素残留总量下降,在猪粪样品中尤为显著,最高下降23.8%.猪粪中四环素类、氟喹诺酮类和磺胺类抗生素在光培养下的降解总体高于避光培养,且光照降低猪粪中磺胺耐药细菌数量,增加细菌群落多样性和有机质降解相关细菌丰度.光照对鸡粪发酵中抗生素降解的影响在不同样品和光照时间之间差异显著,可抑制部分样品中磺胺类抗生素降解,并伴随磺胺耐药细菌数量的增加以及细菌群落丰度和多样性的下降.有针对性地在养殖粪便尤其是猪粪的堆肥场所提供适度光照将有助于抗生素的削减.

Effect of light illumination on antibiotic degradation and microbial community in manure

This work investigated the effect of light illumination on antibiotic degradation during manure fermentation. The concentrations of antibiotic residues and bacterial communities in pig and chicken manure samples after solid-state incubation under dark and light conditions were analyzed. Results indicated that light illumination improved the removal of antibiotic residues in manure samples, particularly in pig manure, showing a maximum decline of 23.8% in the total antibiotic concentration. All the pig manure samples after a light incubation showed lower residual concentrations of tetracyclines, fluoroquinolones, and sulfonamides than those incubated in the dark. The proliferation of sulfonamides-resistant bacteria in pig manure samples could also be inhibited by light illumination, accompanied by increases in the diversity of the bacterial community and the abundances of some bacterial genera relating to organic matter degradation. In chicken manure, the effect of light illumination on the degradation of antibiotics varied greatly among chicken manure samples and light duration treatments. It was found that light illumination inhibited the degradation of sulfonamides in some chicken manure samples, accompanied by an increase in the sulfonamide resistance bacterial population and a decline in the diversity and abundance of manure bacterial community. This work suggested that supplying appropriate light illumination during the storage or processing processes of animal manure, especially pig manure, could be an option to improve the elimination of antibiotics and antibiotic resistance.