Study Progress on Animal Feces Treatment by Microorganism

With the fast development of livestock breeding,serious environmental pollution issues caused by the large accumulation of animal feces have arisen increasingly. It is of great importance to re-use these organic matter resources in order to ease the environmental and resource problems. And we reviews the significance of microorganism for livestock development and particularly the close relationship between microorganism and biodegradation of animal breeding residues. These bacteria play important roles in odor control,degradation and conversion of organic matters,and even the reduction of animal waste discharging amount by adjusting the feed nutrition proportion or improving the digestibility of nutrients. Consequently,it shows good application prospect of microbe practice in the improvement of contaminated environment resulting from livestock farming residues and the utilization of livestock manure resource.

Transmission of ceftazidime-avibactam-resistant Escherichia coli among pets,veterinarians and animal hospital environment

Ceftazidime-avibactam (CZA) is a recently approved combination synthetic β-lactamase inhibitor used in human clinical medicine. Cases of CZA resistance in humans have already been reported, but limited research has investigated CZA resistance in pets. This study explored the prevalence and transmission of CZA-resistant Escherichia coli (CZAREC) among pets, their owners, veterinarians, and the environment in animal hospitals. A total of 5,419 clinical samples were collected from dogs and cats, along with samples from the environment (n = 5,843), veterinarians (n = 557), and pet owners (n = 368) in animal hospitals. From these samples, 760 Escherichia coli (E. coli) isolates were obtained, out of which 60 were identified as CZAREC. These included 34 isolates from the environment (9.14 %, n = 372), three from veterinarians (8.11 %, n = 37), and 23 from animals (6.82 %, n = 337). No CZAREC isolates were found in pet owners. The predominant sequence types of CZARECs were ST156 (n = 20), ST410 (n = 19) and ST101 (n = 7). Bayesian analysis revealed six clusters comprising 47 isolates from the hospital environment, pets, and veterinaries, displaying genetic relatedness of less than 100 core genome single nucleotide polymorphisms (cgSNPs) between any two isolates in each cluster. Some CZAREC isolates with high genetic similarity persisted in the same animal hospital for four to six months. Moreover, discriminant analysis of principal components indicated that most isolates from different hosts shared a genetic source in the human/dog/cat merged cluster. Overall, evidence of CZARECs transmission was found among pets, the environment, and veterinarians in animal hospitals. The findings emphasize the importance of monitoring CZARECs in the veterinary clinical setting to ensure the health of both pets and humans.

A review on microbial aerosols in livestock and poultry environments:pollution characteristics,damage mechanisms,and mitigation measures

Livestock and poultry breeding environments suffer from serious microbial aerosol pollution,posing a significant challenge to maintaining healthy animal rearing.This study reviewed the sources,pollution status,hazards,pathogenic mechanisms,and mitigation measures of microbial aerosols in livestock and poultry breeding settings,based on research conducted over the past two decades.Notably,the study analyzed the distribution characteristics of aerosol components in various animal houses,with a focus on identifying the main factors affecting these characteristics and the molecular mechanisms by which they damage the animal immune system.Quantitative analysis revealed varying concentrations of bacterial and fungal aerosols in different animal houses,with poultry houses often exhibiting higher concentrations.The dominant bacterial and fungal species varied across different animal houses,emphasizing the complex composition of microbial aerosols.Furthermore,antibiotic-resistant bacteria and genes,particularly those resistant to tetracycline,are prevalent in these environments,challenging disease prevention and control efforts.Thus,the infection source must be controlled through isolation measures and proper waste management.Proper disinfectant use,responsible antibiotic stewardship,biosecurity measures,and alternative disease prevention strategies should be implemented.Future research should focus on developing monitoring technologies for pathogenic microorganisms,implementing purification technologies,and investigating the immune-damaging mechanisms of microbial aerosols.By addressing these areas,we can further understand microbial aerosols in livestock and poultry environments and develop effective strategies to mitigate their harmful effects.This review contributes to the sustainable development of animal farming to ensure the health and welfare of animals.