Emergence of antibiotic resistance due to the excessive use of antibiotics in medicines and feed additives:A global scenario with emphasis on the Indian perspective

Antibiotics were discovered for medicinal applications,notably in the last century and since then,they have been prevalently employed for prophylactic purposes in various sectors in the last few decades.Due to the non-judicial usage of antibiotics in sectors like agriculture,aquaculture,and animal husbandry,and as therapeutic substances,antibiotics have started to become a nuisance for the environment and human beings.Furthermore,the accumulation of antibiotics in the biosphere has led to the development of antibiotic resistance in microorganisms making it difficult to treat a growing number of infections.Hereafter to understand the holistic picture of the impacts associated with antibiotics on the environ-ment,the evolution of individual antibiotic pathways for therapeutic and non-therapeutic purposes needs to be studied along with their effect on the environment.Most of the recent reviews on antibiotics either concentrate on a particular source,pathway or environmental impact;however,the present state-of-the-art review attempts to summarize and update the possible sources of antibiotics,usage,their impact on humans,and environmental health on a global scale with a special emphasis on India.Also,there is a critical discussion about the various methods employed for the removal of antibiotics from an array of sources,on both water and soil matrix.The review finally emphasize that the implication of stringent regulation and selection of appropriate technology are required to alleviate antibiotics menace from the environment.

Development and evaluation of a herbal formulation with antipathogenic activities and probiotics stimulatory effects

Searching alternative feed antibiotics is always a study hotspot in the field of animal production. In this study, the antipathogenic activities and probiotics stimulatory effects of 30 kinds of herbs were screened through Oxford cup method and Hungate roll method. 15 herbs showed significantly antibacterial activities（P〈0.05） against Escherichia coli, Salmonella enteritidis, Salmonella typhimurium and Staphylococcus aureus. Seven herbs showed greatly stimulatory promoting effects on Lactobacillus acidophilus and Bifidobacterium longum. Finally, five herbs were combined for the developed formulation with selective antibacterial properties and they were Mume Fructus（35%）, Isatidis Folium（25%）, Moslae Herba（20%）, Chrysanthemi Indici Flos（13%） and Bupleuri Radix（7%）. The herbal formulation showed significantly antibacterial abilities against four pathogens and stimulatory promoting abilities on two probiotics in vitro and the equivalent activities in broiler chickens in vivo against E. coli and L. acidophilus. The toxicity study showed it had no toxicity, which indicated that it would be a kind of preferred candidate for an alternative antibiotic in future animal production.

Current and future prospects for nanotechnology in animal production

Nanoparticles have been used as diagnostic and therapeutic agents in the human medical field for quite some time, though their application in veterinary medicine and animal production is still relatively new. Recently,production demands on the livestock industry have been centered around the use of antibiotics as growth promoters due to growing concern over microbial antibiotic resistance. With many countries reporting increased incidences of antibiotic-resistant bacteria, laws and regulations are being updated to end in-feed antibiotic use in the animal production industry. This sets the need for suitable alternatives to be established for inclusion in feed.Many reports have shown evidence that nanoparticles may be good candidates for animal growth promotion and antimicrobials. The current status and advancements of nanotechnological applications in animal production will be the focus of this review and the emerging roles of nanoparticles for nutrient delivery, biocidal agents, and tools in veterinary medicine and reproduction will be discussed. Additionally, influences on meat, egg, and milk quality will be reviewed.

Diet medication and beta-glucanase affect ileal digesta soluble betaglucan molecular weight,carbohydrate fermentation,and performance of coccidiosis vaccinated broiler chickens given wheatbased diets

Exogenous enzymes as alternatives to feed antibiotics in poultry has become an emerging research area with the emergence of antibiotic resistance.The objective was to evaluate the effects of diet medication(antibiotics)andβ-glucanase(BGase)on digesta solubleβ-glucan depolymerization,carbohydrate fermentation,and performance of coccidiosis-vaccinated broiler chickens fed wheat-based diets.A total of 1,782 broilers were raised on litter floor pens,and each treatment was assigned to 1 pen in each of the9 rooms.The 3 dietary treatments were based on wheat as the sole grain(control,control+medication and control+0.1%BGase),and the birds were fed the respective treatments ad libitum from 0 to 33 d.Treatments were arranged in a randomized complete block design and analyzed as a one-way ANOVA.Beta-glucanase reduced the peak molecular weight,weight average molecular weight(Mw)and maximum molecular weight for the smallest 10%β-glucan molecules(MW-10%)in ileal digesta at d 11and 33,whereas diet medication reduced Mw and MW-10%at d 33 compared to the control(P<0.01).Beta-glucanase and medication reduced the ileal viscosity at d 11 compared to the control(P=0.010).Ileal propionic acid concentration at d 11 and caecal total SCFA,acetic,and butyric acid concentrations at d 33 were lower in the BGase-supplemented diet than in the control(P<0.05).The BGase-added diet had higher duodenal p H compared to the control at d 33(P=0.026).The effect of medication on carbohydrate fermentation was minimal.Diet medication increased weight gain after d 11,whereas BGase increased the gain for the total trial period compared to the control(P<0.001).Feed intake was not affected by the dietary treatment.Medication and BGase improved feed efficiency after d 11 compared to the control(P<0.001).The response to diet medication was larger than BGase,considering weight gain and feed efficiency after d 11(P<0.001).In conclusion,diet medication and BGase depolymerized high molecular weight ileal solubleβ-glucan and increased overall bird performance.Dietary BGase may benefit bird health in broilers fed wheat-based diets without medication.