Isolation and Identification of Pasteurella multocida and Mannheimia haemolytica from Pneumonic Small Ruminants and Their Antibiotic Susceptibility in Haramaya District, Eastern Ethiopia.

Background: Pasteurella species are frequently encountered as serious diseases in small ruminants. It is the main cause of respiratory pasteurellosis in sheep and goats of all age groups. Methods: The cross-sectional study was conducted from December 2022 to April 2023 in Haramaya district, eastern Ethiopia, to isolate and identify Pasteurella multocida and Mannheimia haemolytica and estimate their prevalence, associated risk factors, and antimicrobial sensitivity of isolates in small ruminants using a purposive sampling method. A total of 384 samples (156 nasal swabs from clinic cases and 228 lung swabs from abattoir cases) were collected. STATA 14 software was used to analyze the data. In addition, multivariable logistic regression analysis was performed to assess an association of risk factors. Results: Out of the 384 samples examined, 164 were positive for pasteurellosis, resulting in a 42.70% prevalence. Similarly, 63 (38.4%) of the 164 positive results were from nasal swabs, while 101 (61.6%) came from lung samples. M. haemolytica accounted for 126 (76.82%) of the isolates, while P. multocida accounted for 38 (23.17%). Of the 63 nasal swab isolates, 33 (37%) were from goats and 30 (42.8%) were from sheep. And 17 (10.89%) and 46 (29.58%), respectively, were P. multocida and M. haemolytica. Of the 46 (40%) of the 101 (44.3%) isolates of the pneumonic lung, samples were from goats, while 55 (48.47%) were from sheep. In this study, the risk factors (species, age, and body condition score) were found to be significant (p < 0.05). Pasteurella isolates evaluated for antibiotic susceptibility were highly resistant to oxacillin (90.90%), followed by gentamycin (72.72%), and penicillin (63.63%). However, the isolates were highly sensitive to chloramphenicol (90.90%), followed by tetracycline (63.63%), and ampicillin (54.54%). Conclusion: This study showed that M. haemolytica and P. multocida are the common causes of mannheimiosis and pasteurellosis in small ruminants, respectively, and isolates were resistant to commonly used antibiotics in the study area. Thus, an integrated vaccination strategy, antimicrobial resistance monitoring, and avoidance of stress-inducing factors are recommended.

Evaluation of the effect of therapeutic durations on small ruminant bacterial pneumonia.

BACKGROUND: Sheep and goat production in Ethiopia is hindered by numerous substandard production systems and various diseases. Respiratory disease complexes (RDC) pose a significant threat to the productivity of these animals. Pneumonia is a common manifestation of respiratory disease complexes and often necessitates a prolonged course of antibiotic treatment. This study aimed to optimize and propose the ideal duration of therapy for pneumonia in sheep and goats. METHODS: The study was conducted from February to June 2021 at the Veterinary Teaching Hospital of the College of Veterinary Medicine and Agriculture, Addis Ababa University. The study recruited 54 sheep and goats presented to the hospital for treatment with a confirmed RDC as determined based on clinical signs and bacteriological methods. The animals were randomly allocated to 5 groups each group receiving 10% oxytetracycline (Phenxyl, Phenix, Belgum) intramuscularly for a duration of 3, 4, 5, 6 and 7 consecutive days. The treatment outcomes were assessed by recording vital signs (body temperature, respiratory rate, heart rate, coughing, and nasal discharges), performing lung ultrasonography (L-USG) as well as collection of nasal swabs for bacterial isolation and molecular identification before and after completion of the treatment. An ordered logistic regression model with random effects was employed to determine the optimal therapeutic duration, taking into account the cumulative scores of the outcome variables across the different groups. RESULTS: Among the 54 sheep and goats treated with 10% oxytetracycline, a total of 74.07% (95% CI, 60.35-85.04) achieved complete recovery, as confirmed through clinical, ultrasound, and bacteriological methods. In Group 1 (G1), out of 12 sheep and goats, 8 (83.0%) recovered completely; in Group 2 (G2), out of 11 animals, 9 (82.0%) recovered completely; in Group 3 (G3), out of 11 animals, 10 (93.0%) recovered completely; in Group 4 (G4), out of 9 animals, 9 (100.0%) recovered completely; and in Group 5 (G5), out of 11 animals, 10 (91.0%) recovered completely. Bacteriological examination of nasal swabs indicated involvement of M. hemolytica in 27 (50.00%) and P. multocida in 13 (24.07%) of pneumonic animals. Detection of specific marker genes confirmed only five of the presumptive M. hemolytica isolates, whilst no isolates tested positive for P. multocida. Post-treatment samples collected from recovered animals did not yield any M. hemolytica nor P. multocida. Based on results from clinical signs, L-USG, and bacterial infection variables, the group of sheep and goats treated for seven consecutive days (G5) showed the highest recovery score compared to the other groups, and there was a statistically significant difference (coefficient (ß) = - 2.296, p = 0.021) in variable score between G5 and G1. These findings suggest that the administration of 10% oxytetracycline for a full course of seven consecutive days resulted in symptomatic and clinical recovery rates from respiratory disease in sheep and goats.

Molecular detection of Coxiella burnetii in tick and blood samples from small ruminants in northwest of Iran.

This survey sought to molecularly detect Coxiella burnetii in Argasidae and Ixodidae ticks attached to small ruminants in the region of West Azerbaijan (Northwest of Iran) and blood samples collected from the same animals. 451 tick samples and 927 blood samples were obtained from sheep (n = 536) and goats (n = 391) and tested by nested PCR for detection of C. burnetii insertion sequence IS1111 or icd gene sequence. The collected ticks were morphologically classified as Rhipicephalus sanguineus, Rhipicephalus turanicus, Hyalomma asiaticum, Hyalomma anatolicum, or Argas reflexus. 14% of ticks (65 in total 43 for IS1111 and 22 for icd gene) tested positive for C. burnetii, none of which were from the Argas genus. Among the 927 blood samples, 218 (23.5%) tested positive for C. burnetii. The positive result from analysis targeting the genes IS1111 and icd were 131 and 87 respectively. As Q fever is a tickborne zoonosis and endemic to Iran, such information is critical for creating effective, coordinated, and strategic tick and pathogen control programs to prevent disease outbreak in domestic animals and humans.

Molecular detection and MST genotyping of Coxiella burnetii in ruminants and stray dogs and cats in Northern Algeria.

Aiming at identifying the reservoir and contamination sources of Coxiella burnetii in Northern Algeria, we investigated the molecular presence of the bacterium in 599 samples (blood, placenta, liver, spleen, and uterus) collected from cattle, sheep, dogs and cats. Our qPCR results showed that 15/344 (4.36%) blood samples and six/255 (2.35%) organ specimens were positive for C. burnetii. In cattle, three (4%) blood and liver samples were positive. In sheep, one blood (1.19%) and 3 (8.57%) placenta samples were positive. At the Algiers dog pound, 8 (10%) and 3 (5%) blood samples were qPCR positivein dogs and cats, respectively. In addition, MST genotyping showed that MST 33 was present in cattle and sheep, MST 20 in cattle,andMST 21 in dogs and cats.

Identification, Biochemical Characterization, and In Vivo Detection of a Zn-Metalloprotease with Collagenase Activity from Mannheimia haemolytica A2.

Respiratory diseases in ruminants are a main cause of economic losses to farmers worldwide. Approximately 25% of ruminants experience at least one episode of respiratory disease during the first year of life. Mannheimia haemolytica is the main etiological bacterial agent in the ruminant respiratory disease complex. M. haemolytica can secrete several virulence factors, such as leukotoxin, lipopolysaccharide, and proteases, that can be targeted to treat infections. At present, little information has been reported on the secretion of M. haemolytica A2 proteases and their host protein targets. Here, we obtained evidence that M. haemolytica A2 proteases promote the degradation of hemoglobin, holo-lactoferrin, albumin, and fibrinogen. Additionally, we performed biochemical characterization for a specific 110 kDa Zn-dependent metalloprotease (110-Mh metalloprotease). This metalloprotease was purified through ion exchange chromatography and characterized using denaturing and chaotropic agents and through zymography assays. Furthermore, mass spectrometry identification and 3D modeling were performed. Then, antibodies against the 110 kDa-Mh metalloprotease were produced, which achieved great inhibition of proteolytic activity. Finally, the antibodies were used to perform immunohistochemical tests on postmortem lung samples from sheep with suggestive histology data of pneumonic mannheimiosis. Taken together, our results strongly suggest that the 110-Mh metalloprotease participates as a virulence mechanism that promotes damage to host tissues.

Detection of immune effects of the Mannheimia haemolytica gamma irradiated vaccine in sheep.

Exposure to gamma rays from cobalt 60 (Co60) can induce a complete inactivation of Mannheimia haemolytica. The inactivated bacterial pathogen is a potential vaccine candidate for immunization of ruminants such as sheep. The subcutaneous administration of irradiated vaccine in a two-dose regimen (4.0 × 109 colony forming unit (CFU) per dose) results in no mortality in any of the vaccinated sheep during immunization and after subsequent challenge of the live bacteria of the same strain of M. haemolytica. A significant rise in serum IgG titer, detected through ELISA, is observed after the passage of two weeks from the inoculation of the first dose whereas, the peak of the mean serum antibody titer occurred after two weeks of booster dose. The vaccination does not bring significant change to the IFN-γ levels in serum. The bacterial challenge of the vaccinated sheep does not induce a further seroconversion relative to serum antibody titer. In conclusion, the vaccinated sheep are protected by the elevated IgG titer and increased levels of IL-4 (Th-2 response) compared to the non-vaccinated sheep. Radiation technology can provide the opportunity for mass production of immunologically safe vaccines against animal and zoonotic diseases. Ethics Approval by the National Research Center Ethics Committee (Trial Registration Number (TRN) no 13,602,023, 13/5/2023) was obtained.

Coxiella burnetii infections from animals and ticks in South Africa: a systematic review.

Coxiella burnetii is a zoonotic intracellular bacterium that is widely distributed and affects domestic animals, wildlife, humans and non-mammalian species. This systematic review was aimed at synthesizing research findings on C. burnetii in both domestic and wild animals of South Africa. The systematic review protocol was registered with Open Society Foundations of systematic reviews ( https://doi.org/10.17605/OSF.IO/8WS ). PRISMA guidelines were followed to collect and evaluate relevant scientific articles published on C. burnetii infecting domestic and wild animals in South Africa. Published articles were sourced from five electronic databases, namely, Google Scholar, PubMed and ScienceDirect, EBSCO and Scopus. Results showed 11 eligible studies involving four domestic animals, three wild animals and one ectoparasite species from seven provinces across South Africa. The occurrence of C. burnetii infection was high in Ceratotherium simum (white rhinoceros) (53.9%), medium in sheep (29.0%) and low in pigs (0.9%). Limpopo province (26%) had the most recorded infections followed by KwaZulu-Natal (19%) and Free State (3%) had the least reported occurrence of C. burnetii. The current study discovered that there is scarcity of published research on prevalence and distribution of C. burnetii infecting domestic and wild animals in South Africa, and this is of concern as this bacterium is an important zoonotic pathogen of "One Health" importance.

Long-lasting infection with Anaplasma ovis in sheep.

Ovine anaplasmosis is an emerging vector-borne disease in Europe caused by Anaplasma ovis. The infection has spread quickly in recent years, causing moderate to severe outbreaks in sheep flocks, leading to relevant economic losses in sheep farming. This wider spread has been associated with global warming and climate change, favouring the maintenance and life cycle of their main vector, the ticks. However, another epidemiological aspect could favour this quick spread. Long persistence infection of Anaplasma ovis has been proposed as a hypothesis in several articles but never scientifically proven. The results of the present study demonstrate that eight adult sheep, both naturally or experimentally infected, maintain Anaplasma ovis load in blood during their whole productive life (4 to 6 years), being permanently infected. In addition, the results suggest that A. ovis bacterial load can be constant or suffer fluctuations, as has been demonstrated in other Anaplasma species. Both aspects can be determinants in the epidemiology and the transmission of the infection.

Molecular and serological detection of Anaplasma spp. in small ruminants in an area of Cerrado Biome in northeastern Brazil.

Anaplasmosis, caused by bacteria of the genus Anaplasma, is an important tick-borne disease that causes economic losses to livestock farms in many countries. Even though Anaplasma spp. have been detected in goats and sheep worldwide, few studies investigate the occurrence and genetic identity of these agents in small ruminants from Brazil. Thus, this work aimed to detect and determine the genetic identity of Anaplasma spp. in small ruminants from the Baixo Parnaíba region, state of Maranhão, northeastern Brazil. For this purpose, blood samples were collected from 161 animals (91 goats; 70 sheep) from 4 municipalities in the Baixo Parnaíba region. Sheep and goat serum samples were subjected to recombinant membrane surface protein (MSP5)-based iELISA. Whole blood samples were subject to DNA extraction and molecular diagnosis using PCR assays for Anaplasma spp. targeting msp1ß, msp1α, 16S rRNA and msp4 genes. Positive samples were sequenced and then subjected to Anaplasma marginale msp1α genetic diversity analysis and phylogenetic inferences based on the 16S rRNA and msp4 genes. The serological survey detected the presence of anti-A. marginale IgG antibodies in 18 animals (11.1%): 2.9% (2/70) sheep and 17.4% (16/91) goats. Anaplasma marginale DNA was detected in 2 goats (1.2%) using qPCR based on the msp1ß gene. Two distinct A. marginale msp1α strains, namely α ß and α ß ΓγΓγΓγΓγ were found in the infected goats, each one found in a different animal, both belonging to the H genotype. Phylogenetic analysis based on the 16S rRNA gene showed the sequences positioned in three different clades and grouped with sequences from 'Candidatus Anaplasma boleense', A. platys and A. marginale. Phylogenetic inferences based on the msp4 gene positioned the sequence variants in the A. marginale clade. The present work represents the first molecular detection of sequence variants phylogenetic associated to 'Candidatus Anaplasma boleense' and A. platys and α ß and α ß ΓγΓγΓγΓγ in goats from Brazil.

Molecular epidemiology of Coxiella burnetii infection in sheep and goats in Henan province, China.

Q fever is a significant zoonotic disease caused by Coxiella burnetii, an obligate intracellular gram-negative bacterium. Although C. burnetii infection has been identified in various animal species, domestic ruminants serve as the primary reservoirs and main sources of human infection. Understanding of the epidemiology of C. burnetii in domestic ruminants is crucial for preventing and controlling of C. burnetii infection in humans. In this study, spleen tissues from sheep and goats were collected in Hennan province, China. Through PCR screening, C. burnetii was detected in sheep and goats in Henan province with an overall infection rate of 6.8 %. Sequence comparison and phylogenetic analysis revealed that all newly identified C. burnetii strains shared a close genetic relationship with those found in humans worldwide. These findings highlight the high risk of C. burnetii infection among slaughterhouse workers and emphasize the importance of epidemiological studies that investigate samples from both humans and animals within the "One Health" framework. Such surveillance will contribute to a better understanding of the epidemic situation and aid in the development of effective prevention and control strategies for C. burnetii infections in humans.

First report on genotypic estimation of MRSA load in udder of nomadic sheep flocks affected with subclinical mastitis in Pakistan.

Mastitis is one of the highly devastating issues responsible for production and economic losses in all dairy animals including sheep. This study was designed to investigate subclinical mastitis (SCM) associated with S. aureus in lactating nomadic ewes, along with the associated risk factors analysis. Furthermore, molecular characterization and antibiogram profiling of local methicillin-resistant S. aureus (MRSA) isolates of ovine origin were also performed. A total of 384 milk samples (n = 384) were collected from 13 nomadic sheep flocks using a convenient sampling technique. SCM was evaluated using a Surf Field Mastitis test and the S. aureus was isolated using standard microbiological techniques. Kirby-Bauer disc diffusion assay was used for phenotypic identification of MRSA while the mecA gene was tested through PCR. Study results revealed that SCM was prevalent at 34.37% while S. aureus association was recorded at 39.39%. MRSA prevalence was 36.53% and 21.15% using phenotypic and genotypic tests, respectively. The mecA gene sequences of study isolates showed maximum resemblance with already reported sequences from Pakistan, China, and Myanmar. MRSA isolates showed maximum resistance towards penicillin, ceftriaxone sodium, and trimethoprim + sulphamethoxazole while gentamicin, ciprofloxacin, and tylosin showed maximum efficacy. Risk factors analysis revealed that various flock management, housing, and host-related factors positively influenced the incidence of S. aureus-associated SCM. This study is the first report on the prevalence of S. aureus and MRSA associated with SCM in lactating ewes in Pakistan. This study will help to devise effective treatment and control strategies for S. aureus-associated SCM.

Fungi, including Pithomyces chartarum cause facial eczema and inflammation in grazing sheep in Western China.

Facial eczema is often found in flocks of grazing sheep in China. To investigate fungi species those cause disease and pathological roles. Forage and soil samples were collected during the pathogenic season and cultured. Samples were collected from regions with and without facial eczema affected sheep. Fungal isolation and identification, statistical analysis of fungal species and distribution were performed. Pathological changes, biochemical parameters of serum liver function and protection of inflammatory factors that tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-12 (IL-12) were observed. Fungal cultivation and identification showed that separation rate of Alternaria, Pithomyces chartarum, Fusarium and Aspergillus were higher, particularly, Pithomyces chartarum was significantly identical. Pathological anatomy and histology indicated that the disease likely attacked merino ewes with the age of 6 months old. The clinical manifestations were characterized by inflammational edema in face (ears and eyelids) and mandibular area. Postmortem examination of dead lambs showed enlargement of liver with yellow white patchs of necrotic lesion and tuberous sclerosis and fibrosis on section. Histologic examination of liver showed extravasated blood, severe lesion of liver cells and bile duct, and fatty degeneration. In sheep, fungal toxin induced the secretion of TNF-α, IL-6 and IL-12. These results revealed that Pithomyces chartarum maybe caused facial eczema and inflammation in sheep. The facial eczema was allergic eczema caused by hepatic dysfunction and hepatonecrosis.

The virulence of Dichelobacter nodosus, measured by the elastase test, is an important predictor for virulent footrot diagnosis in New South Wales sheep flocks.

Ovine footrot is a contagious bacterial disease that causes foot lesions, and depending on the virulence of the causative strains, may lead to severe underrunning of the hoof and lameness. Virulent footrot can be identified, treated and controlled more effectively than less virulent benign forms. The in vitro elastase test for virulence of the causative bacteria, Dichelobacter nodosus, has been used to support clinical diagnosis. However, not all laboratory-designated virulent D. nodosus strains cause clinical signs of virulent footrot. This study evaluated retrospectively how well the elastase test supported clinical footrot diagnosis in 150 sheep flocks examined for suspect footrot in New South Wales between August 2020 and December 2021. Flocks were included if measures of clinical disease, environmental conditions and the virulence of D. nodosus isolates were available. Variation in the elastase activity result between D. nodosus isolated from the same flock made bacterial virulence hard to interpret, but calculating the mean elastase rate for all isolates from the same flock made correlations between bacterial virulence and flock footrot diagnosis possible. Simplifying bacterial virulence into whether there were any elastase-positive D. nodosus isolates before 12 days increased the predictive value of elastase results for virulent diagnosis, compared with using the first day that any isolate was elastase positive or the percentage of elastase-positive isolates by 12 days, but not all clinically virulent flocks had isolates with elastase activity before 12 days. Logistic regression models were fitted to identify the minimum number of predictors for virulent footrot diagnosis, with models suggesting that virulent footrot diagnosis was best predicted by adding the elastase test result and environmental conditions to the prevalence of severe foot lesions (score 4 and 5). However, performing the same analysis with different breeds, ages of sheep and seasons might highlight other factors important in the diagnosis of virulent footrot.

Epidemiology and Phylogeny of Anaplasma ovis with a Note on Hematological and Biochemical Changes in Asymptomatic Goats Enrolled from Four Districts in Punjab, Pakistan.

Background: Anaplasma ovis is an intra-erythrocytic gram negative rickettsial bacterium that infects small ruminants, resulting in huge economic losses worldwide. Materials and Methods: The present investigation aims at reporting the molecular prevalence of A. ovis in 1200 asymptomatic goats that were enrolled from 4 districts (Layyah, Lohdran, Dera Ghazi Khan, and Rajanpur) in Punjab, Pakistan by targeting the msp4 gene of bacterium. Risk factors associated with the prevalence of A. ovis and phylogeny of bacterium were also documented. Results: 184 out of 1200 (15%) goat blood samples were infected with A. ovis. The prevalence of the pathogen varied with the sampling sites (p = 0.005), and the highest prevalence was detected in goats from Layyah (19%) followed by Rajanpur (17%), Dera Ghazi Khan (15%), and Lohdran district (9%). The represented partial msp4 gene amplicon was confirmed by Sanger sequencing and deposited to GenBank (OP225957-59). Phylogenetic analysis revealed that the amplified isolates resembled the msp4 sequences reported from Iran, Mangolia, Sudan, and the United States. Sex and age of goats, herd composition and size, and the presence of ticks on goats and dogs associated with herds were the rick factors associated with the prevalence of A. ovis. Red blood cells, lymphocytes (%), neutrophils (%), hemoglobin, and hematocrit levels in blood and Aspartate amino transferase, urea, and creatinine levels in serum were disturbed in A. ovis infected goats when compared with uninfected animals. Conclusion: We are reporting the prevalence of A. ovis in Pakistani goats from four districts of Punjab and these data will help in developing the integrated control policies against this tick-borne pathogen that is infecting our goat breeds.

Evidence of novel Treponema phylotypes implicated in contagious ovine digital dermatitis and association of treponemes with major lameness causing foot pathogens.

In this study 269 swabs collected from 254 ovine foot lesions and 15 apparently healthy ovine feet were screened by PCR for the presence of major lameness causing foot pathogens viz. Treponema species, D. nodosus, F. necrophorum and T. pyogenes with the presumption that ovine foot lesion positive for Treponema species alone or in association with other three pathogens were categorized as contagious ovine digital dermatitis (CODD). While samples positive for D. nodosus alone or its combination with F. necrophorum and T. pyogenes were considered as footrot (FR) and samples in which F. necrophorum or T. pyogenes was found either alone or in combination were considered as interdigital dermatitis (ID). The overall occurrence of Treponema sp. in ovine foot lesions was 48.0%, and ranged from 33 to 58%. In Treponema positive samples D. nodosus, F. necrophorum and T. pyogenes were present in 34 (27.4%), 66 (54.4%) and 84 (68.5%) in contrast to Treponema negative samples in which these were present in 15 (11.1%), 20 (14.12%) and 17 (12.6%) samples, respectively. The data signifies that Treponema sp. are significantly associated with these foot pathogens and their different combinations with Treponema sp. influence the severity of CODD lesion. The identification of Treponema phylotypes was done by sequencing the 16S rRNA gene fragment of ten representative samples. Out of ten sequences, four (Trep-2, Trep-4, Trep-7 and Trep-10) were identical to Treponema sp. phylotype 1 (PT1) that belongs to phylogroup T. refringens-like, one sequence (Trep-1) was genetically close (90% sequence homology) to Treponema brennaborense while five sequences (Trep-3, Trep-5, Trep-6, Trep-8 and Trep-9) matched with uncultured bacterium clones of treponemes forming separate monophyletic group in phylogenetic tree and could represent new digital dermatitis phylogroup presently containing five ovine specific phylotypes. This is the first report on the presence of Treponema phylotypes other than three digital dermatitis (DD) Treponema phylogroups viz. T. phagedenis-like, T. medium/T. vincentii-like, and T. pedis-like that are frequently detected in CODD lesions. Metagenomic analysis of two representative samples revealed the abundance of genus Treponema in CODD lesion while this genus was absent in swab collected from clinically healthy foot suggesting that it might play primary role in producing CODD. These findings may further aid in understanding the etiopathogenesis of CODD and could help to develop appropriate treatment and mitigation strategies to combat the disease.

Identification of serotypes of Mannheimia haemolytica and Pasteurella multocida from pneumonic cases of sheep and goats and their antimicrobial sensitivity profiles in Borana and Arsi zones, Ethiopia.

Respiratory diseases caused by Mannheimia haemolytica (M. haemolytica) and Pasteurella multocida (P. multocida) have been known to result in a considerable loss due to mortality and reduced production. This study aimed at isolation and identification of M. haemolytica and P. multocida associated with pneumonic pasteurellosis in sheep and goats using bacteriological and molecular techniques. Identification of serotypes of M. haemolytica and P. multocida was done using indirect haemagglutination test. The in vitro antimicrobial sensitivity profiles of the M. haemolytica were tested using standard disk diffusion method. A total of 52 and 78 nasal swabs were collected from pneumonic cases for bacterial isolation and identification in Borana and Arsi zone, respectively. Four hundred sera samples were collected for identification of serotypes. The results showed that 17 of 52 (32.69%; 95% CI 20.33, 47.11) nasal swabs collected from pneumonic animals in Borana yielded positive results for Pasteurella/Mannheimia species, 13 (25.00%; 95% CI 14.03, 38.95) of which were M. haemolytica. None of the samples yielded P. multocida. Twenty-three of 78 (29.49%; 95% CI 19.69, 40.89) nasal swabs collected at Arsi from pneumonic animals yielded positive results for M. haemolytica (17) and P. multocida (6). Secondary biochemical characterization revealed that 14 of the 17 isolates conform to M. haemolytica whereas none of the 6 isolates suspected to be P. mutocida were confirmed. Eleven (84.62%) isolates from Borana and 4 (28.57%) from Arsi were confirmed to be M. haemolytica using PCR targeting the Rpt2 genes. Assay for M. haemolytica serotype A1 revealed all belong to A1. None of the isolates with cultural and morphological features of P. multocida gave positive results by molecular assay. Serological assay identified three serotypes of M. haemolytica namely A1, A2 and A7 almost in all of the samples whereas P. multocida serotype A was detected in 78.75% of the samples. The M. haemolytica isolates tested for susceptibility to antibiotics showed resistance against Bacitracin (83.33%) and Penicillin (50.00%) while they were found susceptible to Gentamycin (100%), Chloramphenicol (100%) and Sulfamethoxazole (100%) and Tetracycline (83.33%). In conclusion, the results of the present study revealed the association of M. haemolytica with pneumonic pasteurellosis in sheep and goats and can be of use in vaccine development in Ethiopia. Nevertheless, further investigations and continuous monitoring of antimicrobial resistance and appropriate selection and prudent use of antimicrobials in livestock sector are required.

A metagenomics approach to characterize the footrot microbiome in Merino sheep.

In the Portuguese Alentejo region, Merino sheep breed is the most common breed, reared for the production of meat, dairy, and wool. Footrot is responsible for lameness, decreased animal welfare, and higher production losses, generating a negative economic impact. The disease is caused by Dichelobacter nodosus that interacts with the sheep foot microbiome, to date largely uncharacterized. In fact, Dichelobacter nodosus is not able to induce footrot by itself being required the presence of a second pathogen known as Fusobacterium necrophorum. To understand and characterize the footrot microbiome dynamics of different footrot lesion scores, a whole metagenome sequencing (WMGS) approach was used. Foot tissue samples were collected from 212 animals with different degrees of footrot lesion scores, ranging from 0 to 5. Distinct bacterial communities were associated with feet with different footrot scores identifying a total of 63 phyla and 504 families. As the severity of footrot infection increases the microorganisms' diversity decreases triggering a shift in the composition of the microbiome from a dominant gram-positive in mild stages to a dominant gram-negative in the severe stages. Several species previously associated with footrot and other polymicrobial diseases affecting the epidermis and provoking inflammatory responses such as Treponema spp., Staphylococcus spp., Streptococcus spp. and Campylobacter spp. were identified proliferating along with the lesions' severity. Although these bacteria are not able to initiate footrot, several evidences have been described supporting their association with the severity and incidence increase of footrot lesions caused by Dichelobacter nodosus and Fusobacterium necrophorum. Further investigation is required to establish the roles of particular taxa and identify which of them play a role in the disease process and which are opportunistic pathogens.

Approaches to increase recovery of bacterial and fungal abortion agents in domestic ruminants.

Abortions in domestic ruminants cause significant economic losses to farmers. Determining the cause of an abortion is important for control efforts, but it can be challenging. All available diagnostic methods in the bacteriology laboratory should be employed in every case due to the many limiting factors (autolysis, lack of history, range of samples) that complicate the investigation process. The purpose of this study was to determine whether the recovery of diagnostically significant isolates from domestic ruminant abortion cases could be increased through the use of a combination of the existing aerobic culture and Brucella selective method with methods that are commonly recommended in the literature reporting abortion investigations. These methods are examination of wet preparations and impression smears stained by the modified Ziehl-Neelsen method, anaerobic, microaerophilic, Leptospira, Mycoplasma and fungal culture. Samples of placenta and aborted foetuses from 135 routine clinical abortion cases of cattle (n = 88), sheep (n = 25) and goats (n = 22) were analysed by the new combination of methods. In 46 cases, bacteria were identified as aetiological agents and in one case a fungus. Isolation of Brucella species increased to 7.4% over two years compared with the previous 10 years (7.3%), as well as Campylobacter jejuni (n = 2) and Rhizopus species (n = 1). Salmonella species (5.9%) and Trueperella pyogenes (4.4%) were also isolated more often. In conclusion, the approach was effective in removing test selection bias in the bacteriology laboratory. The importance of performing an in-depth study on the products of abortion by means of an extensive, combination of conventional culture methods was emphasised by increased isolation of Brucella abortus and isolation of C. jejuni. The combination of methods that yielded the most clinically relevant isolates was aerobic, microaerophilic, Brucella and fungal cultures.

Detection and molecular characterization of Clostridium perfringens, Paeniclostridium sordellii and Clostridium septicum from lambs and goat kids with hemorrhagic abomasitis in Turkey.

BACKGROUND: The pathogenic Clostridia cause neurotoxic, histotoxic and enterotoxic infections in humans and animals. Several Clostridium species have been associated with abomasitis in ruminants. The present study aimed to investigate the frequency, and the presence of virulence genes, of Clostridium perfringens, Paeniclostridium sordellii and Clostridium septicum in lambs and goat kids with hemorrhagic abomasitis. RESULTS: A total of 38 abomasum samples, collected from lambs and goat kids of 1 week to 1 month of age in different farms located in eastern Turkey between 2021 and 2022, were evaluated by histopathology, culture and PCR. At necropsy, the abomasum of the animals was excessively filled with caseinized content and gas, and the abomasum mucosa was hemorrhagic in varying degrees. In histopathological evaluation, acute necrotizing hemorrhagic inflammation was noted in abomasum samples. The examination of swab samples by culture and PCR revealed that C. perfringens type A was the most frequently detected species (86.84%) either alone or in combination with other Clostridium species. P. sordellii, C. perfringens type F and C. septicum were also harboured in the samples, albeit at low rates. Beta2 toxin gene (cpb2) was found in three of C. perfringens type A positive samples. CONCLUSION: It was suggested that vaccination of pregnant animals with toxoid vaccines would be beneficial in terms of protecting newborn animals against Clostridial infections. This study investigated the presence of clostridial toxin genes in abomasal samples for the first time in Turkey.

Distribution and Molecular Epidemiology of Anaplasma ovis in Melophagus ovinus and Small Ruminants in Border Regions of South Xinjiang, China.

Background: Anaplasma ovis are obligate intracellular bacteria that can endanger human and animal health, and they can be transmitted by arthropod vectors, such as Melophagus ovinus and ticks. Materials and Methods: In this study, 433 specimens, including 370 M. ovinus and 63 sheep blood samples, were collected from nine districts of South Xinjiang to investigate the distribution and molecular epidemiology of A. ovis in M. ovinus and small ruminant. Results: DNA of A. ovis was detected in 109 (25.2%, 109/433) of the 433 samples using PCR and sequencing. The analysis of A. ovis msp4 sequences revealed four different genotypes, including genotype III (47.7%; 52/109), GB3 (34.0%; 37/109), AoGOv3 (15.6%; 17/109), and XJ9 (2.8%; 3/109). Conclusions: To the best of our knowledge, A. ovis genotypes GB3, AoGOv3, and XJ9 detected in this study are the first to be reported in M. ovinus, and our data indicate that XJ9 is a novel A. ovis genotype presented herein for the first time. These findings provide important references for the new understanding and prevention of A. ovis in border counties in China.