Evaluation and development of diagnostic tools for rapid detection of Riemerella anatipestifer and Pasteurella multocida in ducks

Abstract

Objectives: Ducks suffer a huge economic loss as a result of infections with Pasteurella multocida and Riemerella anatipestifer, which cause high morbidity and mortality. Because these patho¬gens induce similar clinical symptoms when coinfections occur, it is very difficult to differentiate between them based just on clinical signs. Hence, these major pathogens must be quickly and accurately detected. Materials and Methods: A total of 104 birds ranging from 2 days to 4 weeks old were collected from Egyptian farms, and the outcomes were compared statistically. Conventional cultural iden¬tification procedures and a direct multiplex polymerase chain reaction assay were utilized to recognize both pathogens in a single tube reaction simultaneously. Then, the obtained isolates were characterized phenotypically and genotypically. Results: Clinical signs appear at 2–4 weeks of age with respiratory distress (dyspnea), white fluid feces, and stunting. The scrutinized data demonstrated a significantly higher detection rate by PCR directly compared to classical culture procedures. Pasteurella multocida was detected only by PCR. The disc diffusion technique against ten antibiotics showed absolute susceptibilities to amik¬acin, doxycycline, and florfenicol. High levels of beta-lactam resistance were observed. Riemerella anatipestifer isolates were screened for pathogenicity and plasmid-borne blaTEM genes. All six isolates harbored five virulence genes: aspC, RA46, m28, pstS, and Nlp/P60. Moreover, blaTEM was identified into four isolates and deposited to GenBank with accession numbers OP347083, OP347084, OP347085, and OP347086. Conclusion: These results suggest advanced PCR assays can be applied to the field for rapid and valuable diagnosis of two significant pathogens and focus on the worth of ducks in the propaga¬tion of transferable antibiotic resistance genes into the environment.

Bacteriological evaluation and advanced SYBR-green multiplex real-time PCR assay for detection of minced meat adulteration

“…Due to its simplicity, speed, and specificity, polymerase chain reaction (PCR) applications have been widely used ( Kesmen et al ., 2007 ; El-Demerdash et al ., 2023a ). According to several studies ( Abuelnaga et al ., 2020 ; Shalaby et al ., 2021 ; Megahed et al ., 2023 ), multiplex PCR is a powerful approach that can simultaneously amplify several templates, lower the detection rate, and get beyond the restrictions of a single PCR that only targets one type of meat at a time.…”

Pathognomonic features of Pasteurella multocida isolates among various avian species in Sharkia Governorate, Egypt

“…Little is known about the genetic and histopathological characteristics of P. multocida isolates circulating in different avian species. The pathognomonic features of P. multocida can also change over time due to its ability to acquire new genes through horizontal gene transfer when it encounters other bacteria, such as E. coli (Wilson et al 1993 ; El-Demerdash et al 2023a ; Megahed et al 2023 ). This can lead to the development of new more virulent and difficult to treat strains of P. multocida isolates.…”