Review of hatchery transmission of bacteria with focus on Salmonella, chick pathogens and antimicrobial resistance

Abstract

Commercial hatcheries for poultry potentially provide a sanitary barrier between breeder flocks and their progeny. This is important, particularly within the pyramidal breeding structures serving integrated poultry production systems. However, the operation of hatcheries and their focal position connected with multiple flocks, both on the input and output sides, means that they are vulnerable to becoming disseminators of infectious agents. Of particular concern for hatcheries is the pseudo-vertical transmission of bacteria that are initially deposited at the surface of forming or freshly-laid eggs. These bacteria (of which Salmonella enterica is a prime example) can subsequently be present in the chick, as well as spreading within the hatchery environment to colonise other hatching birds. Furthermore, if such infectious organisms become persistent in parts of the hatchery environment, this allows their repeated transfer to hatching individuals or even (via personnel and fomites) to transfer back into breeding flocks supplying the hatchery. The use of antimicrobial drugs in hatcheries adds the further hazard of seeding progeny with antimicrobial-resistant organisms.The mechanisms of hatchery, egg and subsequent chick contamination have been understood, and strategies to counteract the spread and persistence of infectious agents are wellestablished. However, many studies examining bacterial pathogens and antimicrobial-resistant organisms in poultry production implicate hatcheries, either as a link in a chain or as a source of such agents. The review outlines the challenges posed by hatchery operation to control of bacterial transmission, it examines the contemporary and historical evidence for such phenomena, and it briefly discusses strategies to counteract the issue.

Antimicrobial Resistance of Campylobacter jejuni, Escherichia coli and Enterococcus faecalis Commensal Isolates from Laying Hen Farms in Spain

“…This could partially explain some of the observed AMR prevalence in this productive sector despite the reduced antimicrobial treatments [ 36 ]. This has been previously identified in poultry regarding fluoroquinolone resistance in the absence of fluoroquinolone use [ 37 ].…”

Asymptomatic Carriage of C. botulinum Type D/C in Broiler Flocks as the Source of Contamination of a Massive Botulism Outbreak on a Dairy Cattle Farm

“…Despite the hygiene and biosecurity procedures in the hatcheries, infectious agents can contaminate hatcheries by being transported on or within eggs, on hatchery personnel, on trolleys and trays, or as airborne contaminants ( Wales and Davies, 2020 ). A wide range of microorganisms, such as Salmonella, E. coli, Pseudomonas, Staphylococci, Mycoplasma , or Aspergillus , can be detected in hatcheries and disseminated to chicks and subsequently to farms ( Qureshi, 2002 ; McMullin, 2009 ).…”

Advances in Enteropathogen Control Throughout the Meat Chicken Production Chain

“…Commercial hatcheries are ideal environments for contamination, biofilm formation and dissemination of enteropathogens [3,6,7]. A comprehensive review by Wales and Davies (2020) stated 'Studies of Salmonella contamination and colonisation that employ subtyping techniques can provide good evidence of hatcheries acting as conduit and multiplier for such organisms present in breeder flocks' [8]. Ideally the incoming eggs should be enteropathogen free however in reality this is not commercially practical in many countries.…”