Common viral and bacterial avian respiratory infections: an updated review.

Many pathogens that cause chronic diseases in birds use the respiratory tract as a primary route of infection, and respiratory disorders are the main leading source of financial losses in the poultry business. Respiratory infections are a serious problem facing the poultry sector, causing severe economic losses. Avian influenza virus, Newcastle disease virus, infectious bronchitis virus, and avian pneumovirus are particularly serious viral respiratory pathogens. Mycoplasma gallisepticum, Staphylococcus, Bordetella avium, Pasteurella multocida, Riemerella anatipestifer, Chlamydophila psittaci, and Escherichia coli have been identified as the most serious bacterial respiratory pathogens in poultry. This review gives an updated summary, incorporating the latest data, about the evidence for the circulation of widespread, economically important poultry respiratory pathogens, with special reference to possible methods for the control and prevention of these pathogens.

Antibiotic resistance and extended-spectrum ß-lactamase in Escherichia coli isolates from imported 1-day-old chicks, ducklings, and turkey poults.

AIM: Antimicrobial resistance is a global health threat. This study investigated the prevalence of Escherichia coli in imported 1-day-old chicks, ducklings, and turkey poults. MATERIALS AND METHODS: The liver, heart, lungs, and yolk sacs of 148 imported batches of 1-day-old flocks (chicks, 45; ducklings, 63; and turkey poults, 40) were bacteriologically examined for the presence of E. coli. RESULTS: We isolated 38 E. coli strains from 13.5%, 6.7%, and 5.4% of imported batches of 1-day-old chicks, ducklings, and turkey poults, respectively. They were serotyped as O91, O125, O145, O78, O44, O36, O169, O124, O15, O26, and untyped in the imported chicks; O91, O119, O145, O15, O169, and untyped in the imported ducklings; and O78, O28, O29, O168, O125, O158, and O115 in the imported turkey poults. The E. coli isolates were investigated for antibiotic resistance against 16 antibiotics using the disk diffusion method and were found resistant to cefotaxime (60.5%), nalidixic acid (44.7%), tetracycline (44.7%), and trimethoprim-sulfamethoxazole (42.1%). The distribution of extended-spectrum ß-lactamase (ESBL) and ampC ß-lactamase genes was bla TEM (52.6%), bla SHV (28.9%), bla CTX-M (39.5%), bla OXA-1 (13.1%), and ampC (28.9%). CONCLUSION: Imported 1-day-old poultry flocks may be a potential source for the dissemination of antibiotic-resistant E. coli and the ESBL genes in poultry production.

Antibiotic resistance and polymorphism in the quinolone resistance-determining region of Campylobacter spp. isolated from 1-day-old ducklings.

Thirty-three isolates of Campylobacter coli and three isolates of Campylobacter jejuni were recovered from 150 1-day-old ducklings. All isolates were sensitive to chloramphenicol and amikacin, but resistant to sulfamethoxazole-trimethoprim (SXT) by the disc diffusion method. Most isolates were susceptible to tetracycline and erythromycin, but resistant to ofloxacin and ciprofloxacin. Of the 33 C. coli isolates, nine were positive for the tetracycline resistance gene tet(O), although only two of these were resistant to tetracycline in the disc diffusion test. None of the isolates possessed mutations in the quinolone resistance-determining region (QRDR) of the gyrA gene infrequently linked to FQ-resistance. The finding indicated that ducklings may be a source of antibiotic resistant Campylobacter spp. with potential poultry and public health hazard.