Prior to the 2000s, swine dysentery was considered to be caused only by Brachyspira hyodysenteriae with contributing commensal intestinal anaerobes. Nowadays, it is known that the disease is caused by three strongly beta-haemolytic species of the anaerobic spirochaetal genus Brachyspira, i.e. B. hyodysenteriae and newly emerged B. hampsonii and B. suanatina.

A total of 180 samples were taken from diseased and freshly dead broiler chickens of various ages from various farms in El-Minya and Beni-Suef governorates and transferred to the lab for bacterial isolation and further molecular examination targeting E. coli. The results showed that 91 of 180 samples (50.6%) tested positive for E. coli. The   prevalence of some in vitro virulence markers of avian pathogenic E. coli was Congo red binding (CRB) (95.6% positivity) and moderate to strong biofilm production (92%). On 5% sheep blood agar, (67%) of examined isolates showed alpha hemolysis, while (27%) showed gamma hemolysis  and (5.5%) showed beta hemolysis. All the tested isolates exhibited a multidrug resistance (MDR) pattern. E. coli isolates demonstrated various degrees of resistance against, amoxicillin–sulbactam (82%) followed by streptomycin (76%), cefotaxime and trimethoprim/sulphamethoxazole (73%), tetracycline and ciprofloxacin (68%), chloramphenicol (66%), cefaclor (65%), cefixime (62%) respectively. Five MDR selected isolates were examined using PCR. The intended virulence genes were iss, tsh, fimH, and iroN genes. The genes iss and fimH were detected in all of the isolates investigated, whereas iroN was present in four isolates but tsh was found in only one isolate.

Streptococcosis is a zoonotic bacterial disease in tilapia and other fresh that creates economic losses, caused mainly by Streptococcus agalactiae and Streptococcus iniae. The hazard of the disease is that it may present apparently healthy as well as its presence in culture water. So, this work aimed to detect streptococci in Nile tilapia farms located in Assiut and Minia Governorates, Egypt. Streptococcus agalactiae (42 isolates) and Streptococcus iniae (59 isolates) were identified. Two Streptococcus agalactiae isolates were molecularly confirmed and exhibited resistance to most antibiotics and a multiple antibiotic resistant index of 0.9-1. The identified isolates could not form biofilm. Identification of these hemolytic, resistant Streptococcus poses a potential hazard for human health; hence, alternative antimicrobials should be searched against infections caused by these bacteria.

Brucellosis is a major threat to public health especially in developing countries including Pakistan. This study reveals the characterisation of Brucella species affecting humans and goats in the Swat region of Khyber Pakhtunkhwa, Pakistan. Blood samples were collected from shepherds and goats and analysed by Rose Bengal precipitation test (RBPT), standard plate agglutination test (SPAT), polymerase chain reaction (PCR) and Sanger sequencing of 16S rRNA gene. The findings of the study indicated 24% (36/150) and 11.3% (17/150) positivity for Brucella abortus and Brucella melitensis, respectively, in human samples. In samples of goats, 26.66% (40/150) were positive for B. abortus and 16.66% (25/150) samples were positive B. melitensis by SPAT. The species-specific PCR confirmed B. abortus in 24% (36/150) of human samples and 26.66% (17/150) of goat samples by targeting the IS711 locus. The remaining seropositive samples were confirmed as B. melitensis using IS711 M species-specific primer. The sequences of the amplified fragments of the 16S rRNA gene were blasted, and phylogenetic analysis revealed that Brucella species circulating in the Swat district were closely related to B. melitensis and B. abortus reported from India, China, Philippines, and the United States (US) showing the existence of the possible epidemiological linkage among the Brucella species. This study concluded that there was a higher prevalence of B. abortus (26.6%) in humans and goats compared to B. melitensis (16.6%). These results revealed that the Brucella species were circulating in both humans and goats in the study areas. The findings of the study concluded that B. abortus and B. melitensis were circulating in goats and shepherds with a higher prevalence of B. abortus than B. melitensis. Furthermore, the Brucella species identified in Swat were phylogenetically related to the Brucella species reported from India, China, Philippines and the US. Contribution: The proposed study covers the scope of the journal. The species of the genus Brucella affect both animals and shepherds. This study investigates the seroprevalence of brucellosis in shepherds and goats in different geographical areas in the Swat district. The phylogenetic analysis of the Brucella spp. identified in Swat showed close relationships to the Brucella species reported in India, China, Philippines and the US, which shows the possible epidemiological linkages between the Brucella spp.

Mycoplasma gallisepticum (MG) is a major avian pathogen revealing financial losses in poultry industry around the world. The current research aimed to study the bacteriological, molecular detection and sequencing of MG recovered from cases with chronic respiratory disease (CRD) from broiler and layer chicken farms in some Egyptian governorates. Therefore, a total of 125 samples were collected from (25) flock/governorate, representing (15) broiler chicken and (10) laying chicken farms from five Egyptian governorates (Giza, Al-Qalyubia, AL-Dakahlia, Al-Faiyum, AL-Sharqia) from March 2020 till January 2022. The isolates were characterized by using conventional methods and molecularly identified by using (16S rRNA), (mgc2) specific primers for MG. The bacteriological isolation showed that 80.8% (101/125) samples appeared as fried egg colonies on PPLO agar while the rest 24 samples were negative. Only 88 out of 101 (87.1%) bacteriologically positive samples were positive by conventional PCR. Gene target sequencing (GTS) was carried out on one MG isolate with positive PCR mgc2 specific gene. The incidence of MG increases in winter and autumn compared to summer and spring. The sequenced isolate of mgc2 gene is grouped with field strain isolated from Egyptian chickens with 100% identity. The obtained findings indicated that the mgc2 gene could discriminate between MG field type and vaccinal F-strain, MG remains a serious avian pathogen and the study recommend a periodical molecular monitoring of MG in poultry flock with sequence analysis of the circulating strains and further investigations should be applied to detect most suitable control and preventive measures to solve such problem.

The objective of this work was to determine the seroprevalence of brucellosis among camel obtained from El Shalateen area, Red Sea governorate.  Identification of   Brucella isolates, from naturally infected slaughtered camel, using bacteriological and molecular methods to identify the prevalent field strain in camels. This investigation was carried out on 470 camels during the period from July 2020 to June 2021 in El Shalateen area, Red Sea governorate, Egypt using Modified Rose Bengal plate test (mRBPT), Immunochromatographic Assay (ICA) and further confirmation by complement fixation test (CFT) for evaluation of the seroprevalence of camel brucellosis and characterization of Brucella microorganism on bacteriological and molecular basis. The results revealed that the seroprevalence was 10.9%, 8.9%, and 8.5% using mRBPT, ICA and CFT, respectively. The results revealed that there is a highly significant association between brucellosis diagnosed by mRBPT and CFT and the age of the camel. The highest percentage of seropositivity was recorded in older camels > 6y, (p-value < 0.0001). While brucellosis by ICA showed a significant relationship with age (P < 0.05). But there was a non-significant association between brucellosis diagnosed by mRBPT, ICA, and CFT and the sex of the camel, (P > 0.05). The results also revealed that the sensitivity was 100% for mRBPT and ICA While the specificity was 97.44% and 99.53% for mRBPT and ICA, respectively using CFT as the gold standard test. Brucella isolation was 6.7% isolated from costocervical and precrural lymph nodes, liver spleen, and testicles which were identified biochemically as Brucella melitensis biovar 3. DNA extraction and PCR amplification from isolates revealed 5 out of 5 isolates with a molecular size of 282 bp identified as Br. melitensis DNA. In conclusion, ICA can be used as a rapid screening and confirmatory test for the diagnosis of camel brucellosis. Besides, CFT is still a gold standard test because of its balance between sensitivity and specificity.

Poultry bacterial pathogen is a major problem in poultry farms, with serious consequences for poultry and human. Two hundred samples of apparently health and freshly died broiler were collected from different commercial farms at Sharkia governorate, Egypt. Salmonella spp. detected in (29%) of examined specimens and serologically identified into S. Typhimurium, S. Kentucky, S. Infantis, S. Enteritidis and S. Agama with percentages 9.5%, 6.5%, 5%, 4.5% and 3.5%, respectively. Meanwhile, Pseudomonas spp. detected in (19%), the most prevalent serotype was P. aeruginosa O2, O5, O9, and O11. However, the antimicrobial-resistant strains of pathogens continuously emerge, with ineffective of medical treatments, thus, the isolates were examined for detection of multidrug resistant (MDR), doxycycline exhibited the highest antimicrobial activity against Salmonella spp. (55.17%); and ceftriaxone and doxycycline against Pseudomonas spp. (52.63%). Uniplex PCR examination for ampC, stn, tetA(B), integrase genes on MGEs were detected in all Salmonella spp. isolates, and mexR, tetA (B), integrase genes in all examined MDR P. aeruginosa isolates, meanwhile, exoU detected in 80% on MGEs. A novel antibacterial strategy was achieved to minimize economic burdens and the health associated with antimicrobial resistance which obliterate pathogens without any adverse effects on poultry and human. Therefore, the application of a trial using M. Oleifera nanoemulsion in order to control the multidrug resistant genes expression. These findings demonstrated that M. oleifera nanoemulsion was a good choice to its potential as a drug that can be used against Salmonella and P. aeruginosa in poultry industry.

Heartwater, one of the major tick-borne diseases of some domestic and wild ruminants in Africa, is caused by Ehrlichia ruminantium. The genetic diversity of E. ruminantium isolates renders the available vaccine ineffective against certain virulent isolates. To better understand the E. ruminantium genotypes in South Africa, a total of 1004 Amblyomma hebraeum tick deoxyribonucleic acid (DNA) samples from cattle in three South African provinces were tested by pCS20 Sol1 real-time polymerase chain reaction (qPCR) and characterised by multilocus sequence typing (MLST) using five housekeeping genes. Out of 1004 samples tested, 222 (22%) were positive for E. ruminantium. The occurrence of E. ruminantium in Mpumalanga, KwaZulu-Natal and Limpopo provinces was 19%, 22% and 27%, respectively. The E. ruminantium positive samples were screened for housekeeping genes and sequenced. Phylogenetic analysis revealed three main lineages: clade 1 made up of worldwide isolates (eastern, southern Africa, and Caribbean isolates), clade 2 comprised only West African isolates and clade 3 consisted of Omatjenne, Kümm2 and Riverside. Some study sample sequences were not identical to any of the reference isolates. However, they could all be grouped into the worldwide clade. Genetic variation in the sequenced regions was observed in the form of single nucleotide polymorphisms (SNPs). Using MLST to characterise E. ruminantium field isolates allowed the South African genotypes to be clearly distinguished from the distinct West African isolates. Contribution: Characterisation of E. ruminantium field isolates is important for the control of heartwater and contributes to preliminary knowledge required for the development of a more practical vaccine against heartwater.

Fish is one of the most widely advertised foods, and Egypt is now recognized as a significant global fish producer. Human and animal intestinal illnesses and significant histotoxic illnesses are caused by foodborne microorganisms as Clostridium perfringens (C. perfringens). This study was directed to monitor the prevalence, antibiotic susceptibility testing, detection of some virulence and antibiotic resistance genes of multidrug-resistant C. perfringens recovered from fish. A total of 300 samples were collected from gills and intestine of Catfish, Tilapia and Dennis.  Bacteriological examination was conducted, the obtained C. perfringens strains were tested for antibiogram, PCR screening of virulence and antibiotic resistance genes. The investigated samples showed C. perfringens prevalence of 48.3%. C. perfringens isolates were resistant to several antibiotics as clindamycin (90%), cefprozil (80%), novobiocin (80%), aztreonam (80%) and erythromycin (80%). While, isolates were sensitive to nalidixic acid (90%), ofloxacin (90%), chloramphenicol (90%) and rifampicin (80%). Multidrug-resistant (MDR) C. perfringens was detected in 80% of tested strains. PCR proved that the obtained C. perfringens strains were carrying the virulence genes: cpa, cpb and cpe in a prevalence of 60%, 40% and 10%, respectively. As well, bla and ermB antibiotic resistance genes were detected in C. perfringens strains in a prevalence of 100% for both genes. In conclusion, C. perfringens isolated from fish was multidrug- resistant (MDR) bacteria and was harbored cpa, cpb and cpe virulence genes and bla and ermB antibiotic resistance genes. The development of MDR C. perfringens is conceived as a public health threat.

Chicken infectious anemia virus (CIAV) is an immunosuppressive viral disease causing high economic losses in poultry industry. In this study, 20 farms were represented for a prevalence study of the disease in Ismailia governorate, Egypt.ON532690.1 and ON532691.1 Isolates from bone marrow, thymus loops, liver, and spleen of broiler farms exhibiting some clinical and postmortem signs were used for reverse transcription polymerase chain reaction assay. RT-PCR was used to amplify a 418bp product of the CIAV VP1 gene. Three farms out of 20 (15%) were positive. Phylogenetic tree of partial vp1 amino acids were classified into three groups according to change in H/22/N-Q amino acid indicated that there are three CIAV different strains circulating in Egypt. Hematological investigation revealed significant decrease in RBCs count, hemoglobin concentration, and packed cell volume declared normocytic normochromic anemia.The immunological studies revealed a significant decrease in serum lysozyme, nitric oxide (NO), antioxidants (CAT and GSH), total protein,and in the majority of serum protein fractions in infected chickens (G2) compared to apparently healthy (G1) while there were marked increase in G2 than G1 in A: Gratio. This result guides to review the vaccination programs against CIAV in Egypt forimproving the immune response against the infection.