Detection of Chlamydophila abortus in sheep and goat flocks in southern Italy by PCR using four different primer sets

An epidemiological survey was performed to detect the presence of Chlamydophila (C.) abortus and other members of the order Chlamydiales in ovine and caprine flocks with a history of abortion in southern Italy. Four pairs of primers were compared to evaluate their ability to detect Chlamydiales using purified DNA preparations and tissue samples from aborted foetuses with suspected chlamydial infections. As expected, amplification of DNA of the reference strain C. abortus using primer pairs U23F/23Sigr, 16SF2/23R, CTU/CTL and CpsiA/CpsiB produced fragments of about 600 bp, 585 bp, 1000 bp and 300 bp, respectively. The detection limits of the four PCR tests performed on serial DNA dilutions of the C. abortus reference strain were of 10 pg, 0.1 pg, 0.1 pg and 1 fg of DNA, respectively. The most sensitive amplification of DNA extracted from the organ tissues was obtained with primer pairs CpsiA/CpsiB, which detected Chlamydophila spp. DNA in all infected tissue samples. Only C. abortus was identified during the survey. The presence of this agent was confirmed in 3 out of 27 ovine and caprine flocks included in the survey suggesting that abortion due to C. abortus is uncommon in southern Italy.     

Role of Chlamydophila abortus in ovine and caprine abortion in Sardinia,Italy

Between 1999–2003, 14 321 sera and 646 abortion samples (498 foetuses and 148 placentae) were analysed from 807 sheep and goat farms distributed all over the island of Sardinia. After notification of abortion in a flock, sera collected at random from adult animals were examined to detect antibodies specific to Chlamydophila (C.) abortus by ELISA, whereas foetuses and placenta were analysed by PCR assay. Specific IgG antibodies were detected in 611 (4.8%) sheep and 106 (5.8%) goats. From a total of 2050 ovine and 151 caprine fetal samples including muscle, liver, abomasum, spleen, brain and placenta, 29 (1.4%) ovine and 1 (0.6%) caprine samples were C. abortus PCR-positive. Placenta was the tissue with the highest detection rate. These results indicate that the seroprevalence of C. abortus infection in sheep and goats is very low in Sardinia, and PCR results demonstrate that C. abortus has no significant role in abortion, especially in goats.     

Immunogenicity of adenovirus and DNA vaccines co-expressing P39 and lumazine synthase proteins of <Emphasis Type="Italic">Brucella abortus</Emphasis> in BALB/c mice

Brucella poses a great threat to animal and human health. Vaccination is the most promising strategy in the effort to control Brucella abortus (B. abortus) infection, but the currently used live vaccines interfere with diagnostic tests and could potentially result in disease outbreak. Therefore, new subunit vaccines and combined immunization strategies are currently under investigation. In this study, immunogenicity and protection ability of a recombinant adenovirus and plasmid DNA vaccine co-expressing P39 and lumazine synthase proteins of B. abortus were evaluated based on the construction of the two molecular vaccines. Four immunization strategies (single adenovirus, single DNA, adenovirus/DNA, DNA/adenovirus) were investigated. The results showed that the immunization strategy of DNA priming followed by adenovirus boosting induced robust humoral and cellular immune responses, and it significantly reduced the numbers of B. abortus in a mouse model. These results suggest that it could be a potential antigen candidate for development of a new subunit vaccine against B. abortus infection.     

Isolation of <Emphasis Type="Italic">Chlamydia abortus</Emphasis> from a laboratory worker diagnosed with atypical pneumonia

Background

Identifying the aetiological agent of atypical pneumonia in human can sometimes be a tedious process, especially in cases where Mycoplasma pneumoniae, Legionella species and Chlamydia pneumoniae are ruled out. In such cases, a correct anamnesis of the patient is basic to clarify which pathogens might have produced the infection. For this reason, health professionals including veterinarians and laboratory personnel working with zoonotic pathogens should keep their doctors informed.

Case presentation

A human case of atypical pneumonia linked to Chlamydia abortus is reported. A 47-year-old male, a veterinarian researcher into chlamydiae, developed respiratory symptoms, breathing problems and high fever. Serological analyses ruled out the involvement of several respiratory pathogens, such as M. pneumoniae, Legionella pneumophila, Rickettsia conorii and C. pneumoniae, and Chlamydia abortus was identified as the possible aetiological agent of the infection. The isolation of C. abortus from the patient’s sputum and subsequent molecular analysis confirmed the presence of this microorganism.

Conclusion

As far as we know, although C. abortus has not been previously described as capable of causing pneumonia in humans, this is the first reported case of atypical pneumonia in which C. abortus is thought to have played an aetiological role.

     

Molecular detection of <Emphasis Type="Italic">Chlamydophila abortus</Emphasis>, <Emphasis Type="Italic">Coxiella burnetii</Emphasis>, and <Emphasis Type="Italic">Mycoplasma agalactiae</Emphasis> in small ruminants’ aborted fetuses in southern Iran

Abortion in sheep and goats has become increasingly important worldwide because of the significant economic losses and potential zoonotic implication of commonly involved pathogens. Therefore, this cross-sectional study was conducted in southern Iran to detect the Chlamydophila abortus and Coxiella burnetii, as zoonotic pathogens, and Mycoplasma agalactiae, as a neglected abortifacient agent in small ruminants’ aborted fetuses, by using polymerase chain reaction (PCR). From a total of 300 aborted fetuses (183 sheep and 117 goats), 46 samples (15.5%) were positive by PCR, 11% for C. abortus, 2% for C. burnetii, and 3% for M. agalactiae. Also, the association of suggested risk factors with abortion due to these bacterial agents was investigated using univariable and multivariable logistic regression. Results of the statistical analysis showed significant association of C. abortus with flock size (OR?=?2.82, P?=?0.014), season (P?<?0.05), and the number of pregnancy in the aborted dam (OR?=?2.5, P?=?0.05). Our results indicated that C. abortus has a relatively substantial role in small ruminant abortions, and C. burnetii and M. agalactiae are likely important abortifacient agents in our region, too. Regarding veterinary and/or public health importance of these bacterial agents, more attention from veterinary and/or human health services and, maybe, a surveillance system for control and prevention of them are recommended.     

Influence of the Th2 immune response established by Nippostrongylus brasiliensis infection on the protection offered by different vaccines against Chlamydophila abortus infection

Chlamydophila abortus is the aetiological agent of enzootic abortion in small ruminants in which it infects the placenta to cause abortion during the last trimester of gestation. In a mouse model, a Th1 immune response involving IFN-γ production and CD8⁺ T cells is necessary for the infection to be resolved. The authors previously demonstrated that infection with Nippostrongylus brasiliensis, a rodent gastrointestinal nematode extensively used in experimental models to induce Th2 responses, alters the specific immune response against C. abortus infection, increasing bacterial multiplication in liver and reducing specific IFN-γ production. The aim of the present work was to clarify whether a Th2 immune response has any influence on the success of vaccination using both inactivated and attenuated vaccines. The results showed that the Th2 response established prior to vaccination did not influence the induction of protection offered by the vaccines. However, the effectiveness of this protective response can be altered, depending on the adjuvant employed in the inactivated vaccines, when the Th2 response is established after vaccination, just before challenge with C. abortus.     

Isolation,identification and differentiation of <Emphasis Type="Italic">Campylobacter</Emphasis> 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.     

Use of serology and real time PCR to control an outbreak of bovine brucellosis at a dairy cattle farm in the Nile Delta region,Egypt

Background

Bovine brucellosis remains one of the most prevalent zoonotic infections affecting dairy cattle in developing countries where the applied control programs often fail. We analyzed the epidemiologic pattern of bovine brucellosis in a dairy cattle herd that showed several cases of abortions after regular vaccination with RB51 (B. abortus vaccine). In 2013 thirty dairy cows, from a Holstein-Friesian dairy herd with a population of 600 cattle, aborted five months post vaccination by a regular RB51 vaccine. Blood samples were drawn from milking cows and growing heifers, as well as heifers and cows pregnant up to 6 months. These samples were collected in June 2013 (n?=?257) and May 2014 (n?=?263) and were tested by real time (rt)-PCR as well as serological tests, in particular Rose Bengal Test (RBT), Enzyme-Linked Immunosorbent Assays (ELISA) and Fluorescence Polarization Assay. Tissue specimens were also collected from an aborted fetus and cultured. Isolates were subjected to bacteriological typing tests at the genus and species levels.

Results

Five months post vaccination with RB51 vaccine, Brucella (B.) DNA was detected in blood samples of cows by rt-PCR. The serological tests also revealed the spread of Brucella field strains within the herd in 2013. Four Brucella isolates were recovered from specimens collected from the aborted fetus. These isolates were typed as follows: one B. abortus RB51 vaccine strain and three isolates of B. abortus field strain. The seropositive cows with positive rt-PCR might indicate an infection by the Brucella field strain; while the positive rt-PCR results from seronegative animals may either be due to circulating RB51 vaccine DNA in vaccinated animals or to circulating field strain in infected animals before seroconversion.

Conclusion

The results herein suggest that PCR can be a good supplementary tool in an outbreak situation, if an assay is available that can differentiate vaccine and field strains with a high analytical sensitivity. We recommend using RBT and ELISA in parallel in outbreak situations, to identify as many infected animals as possible during the initial screenings. This test procedure should be repeated for at least three successive negative tests, with one month interval.

     

Diagnosis of ovine chlamydial abortions by PCR-RFLP performed on vaginal swabs

Ovine enzootic abortion is an infectious and contagious disease clinically characterized by abortion and weak neonates, affecting sheep and goats. The etiological agent is Chlamydophila (C.) abortus, which is considered one of the most common animal pathogens of small ruminants; it has important economic implications and represents a significant zoonotic risk. Clinical diagnosis is often difficult because the clinical signs and the pathological lesions are not specific for C. abortus infection, in fact they can also be observed as a result of infections with other abortifacient agents. Moreover, the involvement of the laboratory is necessary to perform the definitive diagnosis. One hundred and seventeen vaginal swabs from sheep with clinical signs related to chlamydial infection were examined by a PCR-RFLP assay that demonstrated high specifity and sensitivity. Six samples were positive for C. abortus. Vaginal swabs are easy to handle and allow to deal with biohazardous material in safety conditions.     

Sample pooling for real-time PCR detection and virulence determination of the footrot pathogen <Emphasis Type="Italic">Dichelobacter nodosus</Emphasis>

Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.     

Cryptosporidium species detected in calves and cattle in Dagoretti,Nairobi, Kenya

A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl–Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans.     

Brucellosis in migratory sheep flock from Maharashtra,India

Brucellosis is a zoonotic disease worldwide distributed and having the economic as well as public health importance. The prevalence of brucellosis among sheep flock having history of abortions was studied. A total of 229 samples comprising of 157 blood and 72 clinical samples (vaginal swabs) were collected from 157 animals. Clinical samples were processed for the isolation of Brucella melitensis. Serum samples (n = 157) were tested by Rose Bengal plate test (RBPT) and i-ELISA. A total of 68 (43.31%) and 104 (66.24%) samples were positive by RBPT and ELISA, respectively. Brucella isolates (n = 2) were recovered from clinical samples. Both isolates demonstrated amplification for bcsp 31 and IS711 genes. On AMOS PCR, both the isolates amplified at 731 bp, i.e., belongs to B. melitensis species. The incidence of B. melitensis in a migratory flock warns the thorough testing and culling of Brucella-infected sheep from the flock on a continuous basis; otherwise, such incidence will be routine and poor farmers will be at a loss.     

Polymorphism of growth hormone receptor (<Emphasis Type="Italic">GHR</Emphasis>) gene in Nilagiri sheep

The allelic variation in the regulatory sequence of growth hormone receptor (GHR) gene influences the growth traits of sheep. A study was carried out to find out the polymorphisms associated with exon 10 of GHR gene and its association with growth traits of Nilagiri sheep. The blood samples were collected from Nilagiri sheep (n?=?103) reared at Sheep Breeding Research Station, Sandynallah, Tamil Nadu, India. DNA was isolated using the phenol-chloroform extraction procedure and eight samples having amplified product of part of exon 10 (895 bp) sequenced. The results indicated transitions of nucleotide G>A at loci G177624A and G177878A. The genotyping frequencies estimated using the tetra-primer amplification refractory mutation system-PCR for GG, GA and AA were 0.262, 0.544 and 0.194, and 0.349, 0.505 and 0.146, respectively. The estimated allele frequencies of G and A nucleotides were 0.5340 and 0.4660, and 0.6015 and 0.3985, respectively, at loci G177624A and G177878A. The effects of both the mutations on growth-related traits viz., birth, weaning (3 months) 6, 9 and 12 months weight in Nilagiri sheep were found to be non-significant. This can be a novel approach to assess growth of sheep using the mutation in GHR gene. Thus, this approach can be useful for further investigation as a molecular marker associated with genetic improvement.     

Prevalence of gastrointestinal nematode infections in goat flocks on semi-arid rangelands of northeastern Mexico

The objective of this study was to determine the prevalence of gastrointestinal nematode (GIN) infection in goat flocks on semi-arid rangelands of northeastern Mexico (25° N, 350–400 mm annual precipitation). The study included 668 pluriparous goats from 18 herds in five municipalities of Coahuila and Nuevo Leon, Mexico. Five genetic groups were considered (predominance of Boer, Nubian, Alpine, Saanen, and Toggenburg). Fecal samples were taken from the rectum of each animal to determine the number of eggs per gram (EPG) of GIN. The prevalence of flocks with GIN infections was 88.9%. Similar results were observed for the number of goats infected in the flocks. The Alpine breed presented the highest prevalence and highest EPG loads of GIN, whereas Boer and Nubian were the genetic groups with the lowest (P?<?0.05) EPG. There was a negative effect of GIN infection on the live weight of goats (P?<?0.05). The GIN genera found were Trichostrongylus spp. and Haemonchus spp. It was concluded that in the goat flocks of the semi-arid zones of Mexico was found a high prevalence of infections with gastrointestinal nematodes. The municipality and the breed of the animals were factors that showed influence on this prevalence and the level of infection of the goats.     

Genotypic analysis of virulence genes and antimicrobial profile of diarrheagenic <Emphasis Type="Italic">Escherichia coli</Emphasis> isolated from diseased lambs in Iran

The aim of the present study was to determine the analysis of virulence genes and antimicrobial profile of diarrheagenic Escherichia coli isolated from diseased lambs. Two hundred ninety E. coli isolates were recovered from 300 rectal swabs of diarrheic lambs and were confirmed by biochemical tests. The pathotype determination was done according to the presence of genes including f5, f41, LTI, STI, bfp, ipaH, stx ₁ , stx ₂ , eae, ehlyA, cnf ₁ , cnf ₂ , cdIII, cdIV, and f17 by PCR method. Sixty-six isolates (23.72%) possessed the STI gene and categorized into entrotoxigenic E. coli (ETEC). Nine isolates (3.1%) and five isolates (1.72%) were positive for the cnf1 and cnf2 genes which categorized into necrotoxic E. coli (NTEC). Hundred and seventeen isolates (40.34%) harbored stx ₁ and/or stx ₂ and classified as Shiga toxin-producing E. coli (STEC). Thirteen isolates (4.48%) were assigned to atypical entropathogenic E. coli (aEPEC) and possessed eae gene. Two isolates (0.68%) were positive for ipaH gene and were assigned to entroinvasive E. coli (EIEC). Statistical analysis showed a specific association between eae gene and STEC pathotype (P?<?0.0001). The most prevalent resistance was observed against lincomycin (96.5%) and the lowest resistance was against kanamycine (56.02%), respectively. The high prevalence of STEC and ETEC indicates that diarrheic lambs represent an important reservoir for humans. ETEC may play an important role for frequent occurrence of diarrhea in lambs observed in this region. Due to high antibiotic resistance, appropriate control should be implemented in veterinary medicine to curb the development of novel resistant isolates.     

Evaluation of PCR methods for detection of <Emphasis Type="Italic">Brucella</Emphasis> strains from culture and tissues

The genus Brucella causes significant economic losses due to infertility, abortion, stillbirth or weak calves, and neonatal mortality in livestock. Brucellosis is still a zoonosis of public health importance worldwide. The study was aimed to optimize and evaluate PCR assays used for the diagnosis of Brucella infections. For this aim, several primers and PCR protocols were performed and compared with Brucella cultures and biological material inoculated with Brucella. In PCR assays, genus- or species-specific oligonucleotide primers derived from 16S rRNA sequences (F4/R2, Ba148/928, IS711, BruP6-P7) and OMPs (JPF/JPR, 31ter/sd) of Brucella were used. All primers except for BruP6-P7 detected the DNA from reference Brucella strains and field isolates. In spiked blood, milk, and semen samples, F4-R2 primer-oriented PCR assays detected minimal numbers of Brucella. In spiked serum and fetal stomach content, Ba148/928 primer-oriented PCR assays detected minimal numbers of Brucella. Field samples collected from sheep and cattle were examined by bacteriological methods and optimized PCR assays. Overall, sensitivity of PCR assays was found superior to conventional bacteriological isolation. Brucella DNA was detected in 35.1, 1.1, 24.8, 5.0, and 8.0% of aborted fetus, blood, milk, semen, and serum samples by PCR assays, respectively. In conclusion, PCR assay in optimized conditions was found to be valuable in sensitive and specific detection of Brucella infections of animals.     

Identification of bacteria present in ulcerative stomatitis lesions of captive sea turtles <Emphasis Type="Italic">Chelonia mydas</Emphasis>

Anthropogenic activities, predation, and diseases have contributed to a decrease in the sea turtle population in recent years. Ulcerative stomatitis is a condition that occurs in both wild and captive populations. The etiology of this condition is associated with bacteria such as E. coli, Citrobacter diversus, Klebsiella spp., Pseudomonas spp., Flavobacter calcoaceticus, Staphylococcus spp., and Flavobacterium spp. Some of these microorganisms are part of the oral microbiota of turtles, but alterations in the immune response can disturb the homeostatic relationship and cause an increase in the population of microorganisms, which in turn can cause disease. This work presents results on the isolation and identification of bacteria present in ulcerative stomatitis lesions in captive C. mydas turtles. Oral mucosa samples from 20 clinically healthy turtles and ten animals with ulcerative stomatitis lesions were studied. The samples were cultivated in enriched and differential media, and the identification was made using an automated method. The results showed a great diversity of bacteria in animals with ulcerative stomatitis with a higher prevalence of S. lentus and C. braakii was higher (60 and 50%, respectively) than in healthy animals. E. faecium was identified in 40% of diseased animals and 55% healthy animals. Turtles in this study had a diverse oral microbiota, and S. lentus and C. braakii may be involved in the etiopathogenesis of ulcerative stomatitis.     

Virulence traits of avian pathogenic (APEC) and fecal (AFEC) <Emphasis Type="Italic">E. coli</Emphasis> isolated from broiler chickens in Algeria

Avian pathogenic E. coli (APEC) is the etiologic agent of avian colibacillosis, the most common disease responsible for chicken morbidity in the world. Although multiple virulence-associated factors were identified, their prevalence in Algeria is still poorly known. In the present research, 92 avian pathogenic E. coli (APEC) isolates were recovered from broilers with clinical signs and lesions of colibacillosis. In addition, 32 E. coli isolates collected from feces of healthy birds (AFEC) were included for comparison. All isolates were investigated by PCR for the presence of a total of 11 virulence-associated genes described for avian pathogenic (iroN, ompT, hlyF, iss, iutA, and fimC) and diarrheagenic E. coli (eae, stx, elt/est, ipaH, and aggR). The sensitivity of 39 APEC isolates to 16 antibiotics was also determined using antimicrobial pretreated microplates. Here, we report that 98% of the examined isolates host at least one of the tested virulence factors. The most prevalent genes in APEC were iutA (90.6%), ompT (86.9%), and iss (85.8%); whereas, iutA (78.1%), fimC (78.1%), and iroN (68.7%) were the highest prevalent genes in AFEC. Our data showed that none of the AFEC isolates harbor any of the tested diarrheagenic genes. Moreover, only elt/est (5.4%), stx (2.1%), and ipaH (2.1%) genes were carried by APEC isolates. We further established that ceftazodime, ceftiofur, mequindox, amoxicillin/clavulanic acid, and meropenem were the most efficient antibiotics against the analyzed APEC isolates. Overall, our findings provide more insights about APEC and AFEC virulence potential in Algeria which could participate in the fight against colibacillosis.     

Evidence of infection in tortoises by Chlamydia-like organisms that are genetically distinct from known Chlamydiaceae species

Nasal lavage fluid was collected from 155 tortoises, mostly Testudo spp., that were kept as companion animals and suffered from nasal discharge. Examination for chlamydial DNA by PCR assays targeting the ompA, ompB, and groESL genes, as well as the 16S rRNA signature region and the 16S-23S intergenic spacer, respectively, revealed 16 (10.3%) positive animals. Sequence analysis of PCR products indicated high homology to the family Chlamydiaceae. Phylogenetic trees constructed from partial sequences of the ompA and 16S rRNA genes showed that the present samples clustered outside the nine species of Chlamydia and Chlamydophila. Sequences of the nearest relative, Chlamydophila pecorum, were still clearly distinct from those of the positive tortoise samples. This suggests that the tortoises had been infected by Chlamydia-like agents, the taxonomic identity and pathogenic importance of which has yet to be established.