Food Animal Production's Antibiotic Usage: Comparison
Please note this is a comparison between Version 1 by Sukanta Chowdhury and Version 2 by Amina Yu.

Antibiotics usage was more commonly reported in commercial chicken and aquaculture than other animal production systems (livestock and backyard poultry). Farmers used antibiotics for both therapeutic and preventive purposes. Many studies detected several antibiotics resistance harmful bacteria in food-producing animals and animal origin foods.

  • food animals
  • antibiotic usage
  • antibiotic resistance
  • Bangladesh

1. Introduction

Drivers of antibiotic resistance are complex in low-middle-income countries, and it requires multi-sectoral involvement to control the spread of AMR pathogens in both humans and animals. A trans-disciplinary One Health approach is necessary to detect AMR’s emergence, identify AMR drivers, and develop interventions to mitigate the AMR in humans and animals [1][9]. Food and Agriculture Organization (FAO) of the United Nations (UN), the World Organization for Animal Health (OIE), and the World Health Organization (WHO), and other professional agencies recognized the multi–sectoral One Health approach to address the public health threat of animal origin [2][3][10,11]. In 2015, WHO established the Global Antimicrobial Resistance and Use Surveillance System (GLASS) to facilitate national AMR and antimicrobial consumption (AMC) surveillance systems and data sharing through a collaborative relationship between the human, animal, and environmental sectors. Bangladesh is one of the participating countries to share AMR surveillance data using the One Health approach [4][12].

In Bangladesh, commercial chicken and aquaculture industries are expanding day by day to meet the increasing demand for animal-source nutrition for humans. Both sectors are playing a significantly important role in the food value chain. The commercial chicken industry mainly includes broiler, layer, and Sonali (a cross-breed of Rhode Island Red cocks and Fayoumi hens) intensive farms, whereas commercial aquaculture comprises ponds (close culture system), tanks, net pens, and cage cultures [5][6][13,14]. Around 20% of rural households have ponds in their homestead, and 30% of total fish production comes from commercial extensive, semi-intensive, and intensive farms [7][15]. Commercial chicken and fish farms perform intensive operations to increase production and minimize disease prevalence. Many types of drugs, including antimicrobials, vitamins, minerals, and antimicrobial growth promoters are extensively used in commercial chicken and aquaculture production sectors [8][9][10][11][12][13][16,17,18,19,20,21]. Despite the massive benefit of treating animal diseases using antimicrobial drugs, the resulting emergence of antibiotic resistance has raised global concerns [14][22]. Many farmers in Bangladesh are less aware of the negative impact of excessive, irrational, and prophylaxis use of antibiotics in animals, and aquaculture. Inadequate veterinary healthcare facilities, insufficient monitoring and regulatory services on antibiotic usage, high occurrence of diseases, and malpractices by unqualified veterinary healthcare providers (quack, drug sellers, and animal feed dealers) contributed a crucial role in the increased and misusage of antibiotics in animal health sectors [13][21].

To contain AMR, the government of Bangladesh approved National Strategy for AMR Containment (ARC): 2017–2021. The objectives of this strategy are to establish a multi–sectoral One Health approach to plan, coordinate, and implement ARC containment activities, ensure rational use of antimicrobial agents in humans and animals, strengthen infection prevention and control measures, strengthen bio-safety and bio-security practices, strengthen the surveillance system for AMR and promote operational research, strengthen regulatory provisions, and establish advocacy, communication, and social mobilization [15][23]. The Government of Bangladesh formulated the first National Drug Policy in 1982 to ensure the drug safety, quality, and control of drug prices for human health [16][24]. However, there is no such drug policy or guideline for the animal production sectors. To stop using antibiotics in animal feed during manufacturing, the Bangladesh government constituted a law named “Bangladesh Fish Feed and Animal Feed Act 2010” [17][25]. Thus far, no study was carried out to determine the existence of antibiotics in animal feed. A significant portion of the antibiotics used in animal production sectors is procured from outside the country. The Directorate General of Drug Administration (DGDA) under the Ministry of Health and Family Welfare monitors regulates the import, packaging, production, licensing, and registration of antibiotics [18][26].

In Bangladesh, minimal information is available to describe the antibiotic usage practices in food-producing animals. On the other hand, several studies were carried out to examine antibiotic resistance. Antibiotic resistance, particularly in commercial chicken production, was explored more than other animal production sectors, including aquaculture and livestock. Notably, to date, the country has no separate policy or guideline for antibiotic usage in animal sectors. More updated information on the extent of antibiotic usage and resistance in food-producing animals is crucial to understand the current situation and design proper interventions to minimize the risk of antibiotic resistance in animals and humans. This narrative review provides an overview of antibiotic usage and antibiotic resistance in food-producing animals in Bangladesh. The findings of this review would help policymakers, animal health experts, and animal as well as fish farmers to understand the antibiotic usage and antibiotic resistance-related problems, which are essential to develop effective policies and guidelines for rational antibiotic use to protect animals as well as human health.

2. Antibiotic Usage and Resistance in Commercial Broiler Chicken

Antibiotics are often used in the broiler production systems in Bangladesh. Antibiotics are used to treat clinically sick chickens as well as growth promotion and prophylactic purposes [9][12][17,20]. The majority of the broiler farms (95–100%) of the broiler farms administered antibiotics during the production cycle  [19][27]. The most common usage of antibiotics was for therapeutic purposes (44%), followed by prophylactic (32%), and growth promotion (8%) [9][17]. Many farmers use combination form antibiotics for their broiler chicken, and the majority (80%) of them administered multiple antibiotics [9][12][17,20]. Tetracycline, colistin, ciprofloxacin, tylosin, neomycin, amoxicillin, trimethoprim, sulfonamides, doxycycline, erythromycin, and tiamulin were identified as common antibiotics [9][12][19][17,20,27].
In Bangladesh, several epidemiological studies reported antibiotic resistance in commercial broiler chicken . E. coli was highly prevalent in broiler chicken. A study detected 100% of cloacal swabs collected from broiler chicken tested positive for E. coli. E. coli isolates from apparently healthy broiler chicken were found 100% resistant to ampicillin and tetracycline followed by sulfamethoxazole–trimethoprim (95%) and nalidixic acid (92%) [20][21][39,42]. The commonly detected oxytetracycline resistant genes were tetA, tetB and tetC gene [22][38]. Another study reported 55% prevalence of Extended-Spectrum Beta-Lactamase (ESBL)-producing E. coli in broiler ceca and feces at households, farms, and live poultry markets. The majority (71%) of the ESBL-producing E. coli isolates showed resistance against fluoroquinolones and cefepime, followed by sulfonamides (65%) and aminoglycosides (31%) [12][20]. Avian origin multi-drug resistant Salmonella is one of the leading causes of food-borne illness in humans [23][44]. Salmonella was detected in 34% cloacal swabs of broiler chicken, and the majority of the Salmonella serovar was S. enterica serovar Typhimurium. Salmonella isolates showed the highest resistance to tetracycline (97%), followed by chloramphenicol (94%), ampicillin (83%), and streptomycin (77%) [24][43]. Colistin use in broiler production was not uncommon. There was an evidence of E. coli isolates that carried colistin-resistant mcr-1 genes and some of them showed resistance against tetracycline, and Beta-Lactam antibiotics [25][26][30,31]. Campylobacter jejuni and Campylobacter coli were highly prevalent in broiler chicken and many isolates showed resistance against amoxicillin, streptomycin, tetracycline, erythromycin, ciprofloxacin, norfloxacin, and azithromycin [27][28][40,45].

3. Antibiotic Usage and Resistance in Duck, Pigeon, Quail, and Sonali Chicken

In Bangladesh, we did not find antibiotic usage data for duck, pigeon, and quail. However, many studies reported antibiotic-resistant bacteria in duck, pigeon, and quail. Salmonella prevalence was 40% in duck, and most of the Salmonella isolates showed resistance against amoxicillin, tetracycline, and tobramycin [29][54]. The prevalence of Pasteurella multocida infection in ducks was 34% and 100% of isolates showed resistance against penicillin G [30][55]. Antibiotics resistance was reported in quail. E. coli isolates from quail showed resistance against amoxicillin, gentamycin, nalidixic acid, and tetracycline, whereas Salmonella spp. showed resistance against amoxicillin, ampicillin, erythromycin, gentamycin, kanamycin, nalidixic acid, and tetracycline. Pasteurella spp. were found resistant against erythromycin, sulfaamethoxazole, and tetracycline [31][56]. The isolated strains of Salmonella in pigeons showed resistance against ampicillin, cephalexin, tetracycline, erythromycin, and colistin sulfate [32][57]. Thus far, no studies were conducted to determine antibiotic usage and resistance in Sonali chicken.

4. Antibiotic Usage and Resistance in Livestock

In livestock, antibiotics are mainly used to treat diseases. Two hospital-based studies reported that antimicrobials were prescribed to treat 56–66% of sick animals [33][34][58,59]. The most commonly prescribed antibiotics were streptomycin–penicillin (31%) followed by sulfadimidine (14%), amoxicillin (11%), gentamicin–sulfadiazine–trimethoprim combination (9%), and tylosin (1%) [33][58]. Shiga toxin-producing E. coli (STEC) and enterotoxigenic E. coli (ETEC) showed multidrug-resistant against erythromycin, trimethoprim–sulfamethoxazole, azithromycin, cephalothin, ciprofloxacin, and nalidixic acid [35][60]. Salmonella strains isolated from diarrheic cattle showed resistance to azithromycin, tetracycline, and erythromycin [36][61]. Staphylococcus aureus isolated from dairy cows showed resistance to oxytetracycline [37][62]. Staphylococcus spp., and Bacillus spp. showed a high level of resistance to ampicillin, amoxicillin, and streptomycin in goats [38][63]. Listeria monocytogenes isolates from cattle showed 100% resistance against penicillin, imipenem, and amoxicillin [39][64].

5. Antibiotic Residues and Resistance in Animal-Origin Foods

In Bangladesh, many studies reported antibiotic residues and antibiotic-resistant bacteria in animal-origin foods. Several antibiotics, including amoxicillin, oxytetracycline, ciprofloxacin, enrofloxacin, fluoroquinolones, sulfonamides, and polymyxin residues were detected in raw meat and liver samples of chicken [9][40][17,65]. Amoxicillin residue and oxytetracycline residues were identified in freshwater fish samples [40][65]. Another study detected oxytetracycline and ciprofloxacin residues in 18% of milk collected from commercial dairy farms [41][66].
Frozen chicken meat samples were tested positive for ESBL producing E. coli and Methicillin-resistant Staphylococcus aureus (MRSA) [42][43][44][45][67,68,69,70]. The E. coli isolated from chicken meat samples were found resistant against multiples antibiotics, such as oxytetracycline, amoxicillin, ampicillin, trimethoprim–sulfamethoxazole, pefloxacin, tetracycline, and carbapenems [44][45][69,70]. S. aureus showed wide-ranging resistance against cefoxitin, nalidixic acid, ampicillin, oxacillin, colistin, amoxicillin–clavulanic acid, amoxicillin, penicillin-G, cloxacillin, oxytetracycline, and cefixime [46][71]. Studies detected Salmonella and S. aureus in chicken egg content and eggshell surface. The Salmonella isolates showed significant resistance against amoxicillin and ampicillin, whereas S. aureus isolates were found resistant to amoxicillin, nalidixic acid, and penicillin [43][47][68,72]. Another study detected Staphylococcus spp., Alcaligenes spp., Klebsiella spp., and Pseudomonas spp. in animal origin frozen foods collected from supermarkets. Contamination was mostly found in chicken nuggets, and the isolated bacteria showed resistance against cefixime, chloramphenicol, nalidixic acid, and azithromycin [48][73]. A study detected 35% of milk samples collected from cows and buffaloes were tested positive for S. aureus, and 9% were positive for E. coli. Most of the S. aureus and E. coli isolates were resistant to gatifloxacin [49][74].