A survey of frequency of virulence and aminoglycoside antibiotic-resistant genotypes and phenotypes in Escherichia coli in broilers in Khartoum State, Sudan.

BACKGROUND: Although Escherichia coli (E. coli) is considered a normal microflora in the poultry intestine, certain strains namely, Avian Pathogenic E. coli (APEC), cause colisepticaemia (fatal disease) in poultry. The aim of this study was to determine the prevalence of the virulence genes, i.e. (iroN, ompT, iss, iutA, and hlyF) and aminoglycoside-modifying enzyme (AME) genes, i.e. (strA and strB) in Escherichia coli strains in broilers in Khartoum State. METHODS AND RESULTS: A total of 25 E. coli isolates were collected from broilers farms. All isolates were screened for antimicrobial susceptibility tests using Kirby-Bauer disc diffusion method. In addition, all isolates were tested for the presence of virulence genes and modifying enzyme genes using the polymerase chain reaction (PCR). The results showed that the prevalence of positive strains to virulence genes were 14 (56%), 21 (84%), 14 (56%), 0 (0%) and 0 (0%) to iroN, iutA, hlyF, ompT and iss, respectively. Combined virulence genes include iroN, hlyF and iutA were detected in 14 (56%). The rates of resistance were as follows: Gentamycin: (32%), Kanamycin: (20%) and Streptomycin (16%). Of the genes tested, strA (72%) was the most commonly recognized gene followed by strB (56%). CONCLUSIONS: It could be concluded that this is the first report of molecular survey of virulence and aminoglycoside-modifying enzyme (AME) resistant genes in APEC isolates from broiler in Sudan. Therefore, prohibition of non-curative application of antibiotic, dishearten their abuse and to be frequently observant by suppling suitable research-based policy for the poultry industry is warranted.

Isolation, identification and differentiation of Campylobacter spp. using multiplex PCR assay from goats in Khartoum State, Sudan.

The aim of this study was to identify and characterize thermophilic Campylobacter species in faecal samples from goats in Khartoum State, Sudan, by application of multiplex polymerase chain reaction. Campylobacteriosis is a zoonotic disease of global concern, and the organisms can be transmitted to human via food, water and through contact with farm animals and pets. There are five clinically related Campylobacter species: Campylobacter jejuni (C. jejuni). Campylobacter coli, Campylobacter lari, Campylobacter upsaliensis and Campylobacter fetus. Conventional cultural methods to diagnose campylobacteriosis are tedious and time consuming. Wide ranges of genes have been reported to be used for PCR-based identification of Campylobacter spp. We used a multiplex PCR assay to simultaneously detect genes from the major five clinically significant Campylobacter spp. The genes selected were hipO (hippuricase) and 23S rRNA from glyA (serine hydroxymethyl transferase) from each of C. jejuni. C. coli, C. lari, and C. upsaliensis; and sapB2 (surface layer protein) from C. fetus subsp. fetus. The assay was used to identify Campylobacter isolates recovered from 336 cultured faecal samples from goats in three localities in Khartoum State. C. coli was the most predominant isolate (234; 69.6%), followed by C. jejuni (19; 5.7%), C. upsaliensis (13; 3.9%), C. fetus subsp. fetus (7; 2.1%) and C. lari (6; 1.8%). Twenty-nine goats showed mixed infection with Campylobacter spp., 21 of which harbored two Campylobacter spp., while eight animals were infected with three species. Ten out of twelve goats that displayed diarrhea harbored C. coli only. C. coli, C. jejuni and C. upsaliensis showed significant variation with localities. The prevalence of C. coli was significantly higher (87; 25.9%) in goats from Omdurman, whereas C. jejuni and C. upsaliensis were significantly higher (11; 3.3%, 9; 2.7%) in goats from Khartoum. The multiplex PCR assay was found to be rapid and easy to perform and had a high sensitivity and specificity for characterizing the isolates, even in mixed cultures. The study demonstrated the significance of goats as reservoirs in the dissemination of Campylobacter spp. which could be considered as potential agent of caprine enteritis and abortion as well as contamination of the wider environment posing serious public health concern in Khartoum State.

Biological Pathotyping of Newcastle Disease Viruses in Sudan 2008-2013.

The biological properties and pathogenicity of seven Newcastle disease virus field isolates were studied. These isolates were recovered from different outbreaks in Sudan (5 from chickens and 2 from pigeons) during 2008-2013. Based on intracerebral pathogenicity index, four NDV isolates were characterized as velogenic (their ICPI ranged 2.0-1.6) and three isolates were characterized as mesogenic (ICPI ranged 1.2-1.3). The mean death time for all isolates ranged from 54 to 76.8 hours. The elution time of the viruses from chicken erythrocytes and the ability to haemagglutinate mammalian red blood cells differed considerably in their reactions.

Isolation and Molecular Characterization of Mycoplasma gallisepticum and Mycoplasma synoviae in Chickens in Sudan.

The current study described the isolation and molecular detection of Mycoplasma gallisepticum (Mg) and Mycoplasma synoviae from tracheal swabs of diseased birds showing signs of respiratory distress in selected commercial (layer and broiler) farms and from yolk and an open air of pens of vaccinated breeder flocks in Sudan. A number of 45 Mycoplasma isolates were recovered from chickens in Khartoum, Gezira, and Equatoria states in Sudan. Of these, eight Mg and three Ms isolates were identified using growth inhibition and rapid serum agglutination (RSA) tests. The conventional PCR technique was applied to amplify 140 bp and 720 bp DNA fragments for the Mg and Ms, respectively. This research confirmed vertical and horizontal transmission of Mg from breeder farms through detection of Mg in yolk of fertile eggs and an air of pens despite previous vaccination. PCR is considered a rapid, sensitive, and cheap method and it will improve the diagnosis of Mycoplasma in chickens.