(Gróf Tisza István Debreceni Egyetemért Alapítvány Kiválósági PhD Ösztöndíj)
Szakterületek:
Biológiai tudományok
Antimicrobial resistance (AMR) is a global health challenge requiring cross-sector
action, with research largely focused on chickens, leaving ducks underexplored. This
study examines AMR dynamics in Ross 308 broilers and Cherry Valley ducks over 15 months
and 15 stocking periods under consistent rearing conditions. A total of 96 pooled
samples were collected: 50 from broiler farms (26 biological, 24 environmental) and
46 from duck farms (24 biological, 22 environmental). Using next-generation shotgun
sequencing, 3,665 distinct AMR types were identified: 1,918 in broilers and 1,747
in ducks. Host-specific AMRs comprised 25.3% in broilers and 18% in ducks, while 56.7%
were shared. AMR diversity declined across production phases, with broilers losing
641 types and ducks losing 308, yet AMR frequencies increased significantly by the
finisher phase ( p < 0.0001). Based on in silico data, prophylactic antibiotic use
significantly reduced the prevalence of multidrug-resistant bacteria in both poultry
species ( p < 0.05). Hospital-acquired infection-associated AMRs were higher in broilers
than in ducks at the start of production but declined significantly by the end of
the rearing period ( p < 0.0001). Above-average resistance markers accounted for
approximately 10% of all detected resistance determinants. Tetracycline and phenicol
resistances emerged as the most prevalent. 13 high-resistance carrier (HRC) species
were shared between both hosts. Broiler-specific HRCs exhibited significantly higher
abundances (relative frequency: 0.08) than duck-specific HRCs (relative frequency:
0.003, p = 0.035). The grower phase emerged as a critical intervention point. In
farm environments 15 broiler-specific and 9 duck-specific biomarker species were identified,
each strongly correlated with poultry-core HRCs (correlation coefficient > 0.7). Broiler
exhibited higher abundances of key resistance genes, with tetracycline resistance
predominantly associated with Bacteroides coprosuis , Pasteurella multocida , and
Acinetobacter baumannii . Despite its limitations, this research provides key insights
into AMR trends in two major poultry types, guiding targeted interventions and sustainable
management strategies.
