With the rampant usage of antibiotics as growth promoters (AGPs) in poultry sector, there has been alarming concerns of antimicrobial resistant microbes such as Escherichia coli. Diversification of poultry farming due to consumer demand for safer products with higher protein content, turkey production is gaining popularity. Feed additives such as formic acid (FA) and thymol (TH) are effectively replacing AGPs due to their antimicrobial action. This directed the researchers to find alternatives to antibiotics such as thymol and formic acid because of their strong antimicrobial, anti-oxidative, digestive-stimulating properties. To assess the efficacy of FA and TH as growth promoters and their effect on the antimicrobial resistance (AMR) load, the current study (0–12 weeks) was conducted in CARI VIRAT turkey poults (n = 256; unsexed) those were randomly distributed into eight treatment groups: control(T1), AGP (T2), graded levels of FA (T3 to T5) @ 2.5, 5 and 7.5 ml/kg and TH (T6 to T8) @ 120, 240 and 350 mg/kg. Cloacal swab samples were collected at 0, 4th, 8th and 12th week interval and processed further for isolation, identification and assessment of resistance profile of E. coli. The final body weight, cumulative gain and FCR were significantly (p < 0.05) better for birds under supplementation. The Total plate count (TPC) and coliforms showcased a significant (p < 0.001) reduction in the FA and TH supplement groups as compared to control and AGP group. The resistance profile indicated E. coli isolates from AGP group with significantly (p < 0.001) highest resistivity against antibiotics (viz. chloramphenicol, tetracycline, nalidixic acid, chlortetracycline) while isolates from FA (T5) and TH (T8) groups were the least resistant. bla_AmpC gene was significantly (p < 0.001) harbored in T2 isolates whereas least detected in T5 and T8. It was inferred that formic acid (7.5 ml/kg) and thymol (360 mg/kg) can effectively replace AGPs and lower AMR burden in poultry.

随着抗生素作为生长促进剂（AGP）在家禽领域的广泛使用，大肠杆菌等抗菌药物耐药性微生物引起了令人担忧的担忧。由于消费者对更安全、蛋白质含量更高的产品的需求，家禽养殖多样化，火鸡生产越来越受欢迎。甲酸 (FA) 和百里酚 (TH) 等饲料添加剂由于其抗菌作用，正在有效取代 AGP。这促使研究人员寻找百里香酚和甲酸等抗生素的替代品，因为它们具有强大的抗菌、抗氧化和刺激消化的特性。为了评估 FA 和 TH 作为生长促进剂的功效及其对抗菌素耐药性 (AMR) 负荷的影响，当前研究（0-12 周）在 CARI VIRAT 火鸡幼禽（n  = 256；未性别）中进行，这些火鸡幼禽随机分布分为八个治疗组：对照（T1）、AGP（T2）、分级水平的FA（T3至T5）@2.5、5和7.5ml/kg以及TH（T6至T8）@120、240和350mg/kg。每隔 0、4、8 和 12 周收集泄殖腔拭子样本，并进一步处理以分离、鉴定和评估大肠杆菌的耐药性。补充后的鸡的最终体重、累积增重和 FCR 明显更好（p  < 0.05）。 与对照组和 AGP 组相比，FA 和 TH 补充剂组的总平板计数 (TPC) 和大肠菌群显着减少 ( p < 0.001)。耐药性特征表明，AGP 组的大肠杆菌分离株对抗生素（即氯霉素、四环素、萘啶酸、金霉素）的耐药性显着最高 ( p  < 0.001)，而 FA (T5) 和 TH (T8) 组的分离株最低抵抗的。bla _AmpC基因在 T2 分离株中显着存在（p  < 0.001），而在 T5 和 T8 分离株中检测到最少。推测甲酸（7.5 ml/kg）和百里香酚（360 mg/kg）可以有效替代AGPs，降低家禽的AMR负担。