Mycoplasma synoviae (MS) and Mycoplasma gallisepticum (MG) are two of the most serious infections in poultry, causing financial losses across the globe. Antibiotics treatment can lessen the clinical signs of MG and MS infection in birds and help restrict the spread of these infections. However, the rise of antibiotics multidrug resistance (MDR) among poultry diseases is still a problem for the world's health. Minimum inhibitory concentration (MIC) is crucial to resolving this issue since it helps ensure correct antibiotic use and fights the development of antibiotic resistance. This investigation aims to assess the in vitro and in vivo efficacy of several antibiotics (tilmicosin, tylosin, erythromycin, spiramycin, lincomycin, and doxycycline) against MG and MS field isolates, in addition to guava leaves extract (GLE) against MG. For in vivo study, 510, one day old chicks were randomly split into 17 groups the birds were experimentally infected at 3 days old and supplied with different treatments in drinking waters for 5 successive days at 18 days old. The results of in vitro study showed that tilmicosin was the most effective against MG isolates with MIC values ranging from 0.0078 to 0.0156 μg/ml and spiramycin considered effective against MS with MIC values ranging from 0.015625 to16μg/ml and MIC value of GLE was 0.25 μg/ml that was considered as moderate sensitive to MG infection. The in vivo study revealed that tilmicosin and spiramycin were able to significantly lower the clinical score, lesion score, and re-isolation rate of MG and MS, respectively in the treated birds at p-value < 0.05 in contrast with control positive infected untreated groups. Additionally, the treated groups with tilmicosin in MG infection and spiramycin in MS infection showed significantly higher mean body weights (MBW) compared to the infected untreated ones at p-value < 0.05. The current study demonstrates that MG and MS's sensitivity to many of the most popular drugs changed as in tylosin become low sensitive and erythromycin become resistant. GLE has moderate sensitivity antibacterial effect against MG isolates both in vivo and in vitro and can be used as a natural antibiotic alternative. Therefore, we recommend periodical monitoring of the sensitivity of the circulation MG and MS strains using MIC test to overcome MDR of avian mycoplasmas with further suggestion to evaluate GLE as nano-preparation against MG infection.

To date, there is limited data about the genetic relationship of Escherichia coli between wild birds and cattle because these birds act as silent vectors for many zoonotic bacteria. This study aimed to elucidate the role of rooming wild birds in the vicinity of cattle farm in transmission of the same pathogenic E. coli variants, identifying their virulence, resistance traits and genetic similarities of fimH virulence gene. About 240 faecal/cloacal swabs were collected from both species and examined bacteriologically. Escherichia coli was yielded in 45.8% and 32.5%, respectively, of examined cattle and wild birds. The most prevalent detected E. coli serovar was O26. High tetracycline and chloramphenicol resistance were recorded; however, gentamycin and ciprofloxacin exhibited the highest sensitivity rates. Polymerase chain reaction (PCR) conserved genotypic resistance (tetA and blaCTX-M) and virulence attributes (fimH, stx1, eaeA and ompA) of E. coli isolates were discussed in detail. The fimH gene revealed 100% sequence similarity when comparing with different E. coli isolates globally and locally. Finally, a close genetic association of E. coli with both wild birds and cattle was detected, thus strengthening its role in the dissemination of the infection via environment. Prevention and conservative policy should be carried as E. coli constitute enormous significant zoonotic risks to livestock and animal workers. Also, further studies to the whole genome sequencing of fimH, other virulence and resistance genes of E. coli are recommended trying to limit the possibilities of co-infection and transfer among different species. CONTRIBUTION: The current study recorded updated data about the critical infectious role of wild birds to livestock, including cattle farms in Egypt. It also delivered some recommendations for good hygienic practices in cattle farms which must be implemented for handling animal manure.