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International Journal of Systematic and... Jun 2023During a screening study for in two unrelated flocks of Muscovy ducks pharyngeal and cloacal swabs were collected. A total of 59 -like isolates sharing the same colony...
During a screening study for in two unrelated flocks of Muscovy ducks pharyngeal and cloacal swabs were collected. A total of 59 -like isolates sharing the same colony morphology were subcultured and subsequently characterized. Colonies on bovine blood agar were nonhaemolytic, regular, circular, slightly raised, shiny, intransparent with an entire margin, greyish and had an unguent-like consistency. Isolate AT1 was characterized by 16S rRNA gene sequencing and showed the highest similarity of 96.1 % to the type strain of and 96.0 % to the type strain of , respectively. In addition, and gene sequences also showed the highest similarity to the genus . The phylogenetic comparison of concatenated conserved protein sequences also showed a unique position of AT1 compared to other species of . Full phenotypic characterization of the isolates showed that between two () and 10 () phenotypic characteristics separate the taxon isolated from Muscovy ducks from the accepted species of . Whole genomic sequences of two strains analysed by the type strain genome server showed the highest similarity of 24.9 % to the genome of the type strain of and 23.0 % to the genome of the type strain of . The species sp. nov. is proposed based on the phenotypic and genotypic similarity to as well as differences to the other validly published species of the genus. The leukotoxin protein was not predicted in the genome of AT1. The G+C content of the type strain of sp. nov., AT1 (=CCUG 76754=DSM 115341) is 37.99 mol%, calculated from the whole genome. The investigation further proposes that is reclassified as a later heterotypic synonym of , since and are closely genetically related, and was validly published before .
Topics: Animals; DNA, Bacterial; Ducks; Mannheimia; Phylogeny; RNA, Ribosomal, 16S; Species Specificity; Pharynx; Cloaca
PubMed: 37358903
DOI: 10.1099/ijsem.0.005947 -
Journal of Medical Microbiology Jun 2023With expanding demand for diagnostics, newer methodologies are needed for faster, user-friendly and multiplexed pathogen detection. Metagenome-based diagnostics offer...
With expanding demand for diagnostics, newer methodologies are needed for faster, user-friendly and multiplexed pathogen detection. Metagenome-based diagnostics offer potential solutions to address these needs as sequencing technologies have become affordable. However, the diagnostic utility of sequencing technologies is currently limited since analysis of the large amounts of data generated, are either computationally expensive or carry lower sensitivity and specificity for pathogen detection. There is a need for novel, user friendly, and computationally inexpensive platforms for metagenome sequence analysis for diagnostic applications. In this study, we report the use of MiFi (Microbe Finder), a computationally inexpensive algorithm with a user-friendly online interface, for accurate, rapid and multiplexed pathogen detection from metagenome sequence data. Detection is accomplished based on identification of signature genomic sequence segments of the target pathogen in metagenome sequence data. In this study we used bovine respiratory disease (BRD) complex as a model. Using MiFi, multiple target bacteria and a DNA virus were successfully detected in a multiplex format from metagenome sequences acquired from bovine lung tissue. Overall, 51 clinical samples were assessed and MiFi showed 100 % analytical specificity and varying levels of analytical sensitivity (62.5 %-100 %) when compared with other traditional pathogen detection techniques, such as PCR. Consistent detection of bacteria was possible from lung samples artificially spiked with 10-10 c.f.u. of .
Topics: Animals; Cattle; Metagenome; Metagenomics; Genomics; Algorithms; Polymerase Chain Reaction
PubMed: 37345698
DOI: 10.1099/jmm.0.001720 -
Veterinary Microbiology Aug 2023Amongst the bacterial pathogens associated with the bovine respiratory disease syndrome (BRD) in cattle are Mannheimia haemolytica and Mycoplasma bovis. The interaction...
Amongst the bacterial pathogens associated with the bovine respiratory disease syndrome (BRD) in cattle are Mannheimia haemolytica and Mycoplasma bovis. The interaction between these two pathogens has not been investigated before; thus, there are gaps in the knowledge of why and how a previous infection with M. haemolytica allows the development of M. bovis-related lesions. We hypothesized that upon M. haemolytica infection, inflammatory products are produced in the lung and that these inflammatory products stimulate M. bovis to produce proteases and lipases that degrade lipids and proteins important for lung function. In this work, we identified several M. bovis proteases and lipases whose expression was modulated by M. haemolytica products in vitro. We performed co-infection animal challenges to develop a model to test vaccine protection. A prior exposure to BHV-1 followed by infection with M. bovis and M. haemolytica resulted in severe pathology and the BHV-1 infection was abandoned. When M. bovis and M. haemolytica were introduced into the lungs by bronchoscopy, we found that M. haemolytica resulted in worsening of the respiratory disease caused by M. bovis. We performed a proof-of-concept trial where animals were immunized with the M. bovis proteins identified in this study and challenged with both pathogens. Despite detecting significant humoral immune responses to the antigens, the experimental vaccine failed to protect against M. bovis disease.
Topics: Animals; Cattle; Bacteria; Cattle Diseases; Mannheimia haemolytica; Mycoplasma bovis; Respiratory Tract Diseases; Proof of Concept Study
PubMed: 37276814
DOI: 10.1016/j.vetmic.2023.109793 -
Scientific Reports Jun 2023Respiratory diseases caused by Mannheimia haemolytica (M. haemolytica) and Pasteurella multocida (P. multocida) have been known to result in a considerable loss due to...
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.
Topics: Cattle; Animals; Sheep; Mannheimia haemolytica; Pasteurella multocida; Pasteurellosis, Pneumonic; Serogroup; Ethiopia; Goats; Pasteurella; Anti-Bacterial Agents; Sheep Diseases
PubMed: 37268660
DOI: 10.1038/s41598-023-36026-2 -
ACS Infectious Diseases Jun 2023Bovine respiratory disease (BRD) is a multifactorial condition where different genera of bacteria, such as , , , and , and viruses, like bovine respiratory syncytial... (Review)
Review
Bovine respiratory disease (BRD) is a multifactorial condition where different genera of bacteria, such as , , , and , and viruses, like bovine respiratory syncytial virus, bovine viral diarrhea virus, and bovine herpes virus-1, infect the lower respiratory tract of cattle. These pathogens can co-infect cells in the respiratory system, thereby making specific treatment very difficult. Currently, the most common models for studying BRD include a submerged tissue culture (STC), where monolayers of epithelial cells are typically covered either in cellular or spent biofilm culture medium. Another model is an air-liquid interface (ALI), where epithelial cells are exposed on their apical side and allowed to differentiate. However, limited work has been reported on the study of three-dimensional (3D) bovine models that incorporate multiple cell types to represent the architecture of the respiratory tract. The roles of different defense mechanisms in an infected bovine respiratory system, such as mucin production, tight junction barriers, and the production of antimicrobial peptides in cultures require further investigation in order to provide a comprehensive understanding of the disease pathogenesis. In this report, we describe the different aspects of BRD, including the most implicated pathogens and the respiratory tract, which are important to incorporate in disease models assembled . Although current advancements of bovine respiratory cultures have led to knowledge of the disease, 3D multicellular organoids that better recapitulate the environment exhibit potential for future investigations.
Topics: Animals; Cattle; Respiratory System; Cattle Diseases; Bacteria; Viruses
PubMed: 37257116
DOI: 10.1021/acsinfecdis.2c00618 -
Veterinary Medicine and Science Jul 2023Small ruminants are the most numerous of man's domestic livestock. Although sheep represent a great resource for Ethiopia, the net rate of productivity per animal is...
Isolation and identification of Mannheimia haemolytica and Pasteurella multocida from symptomatic and asymptomatic sheep and their antibiotic susceptibility patterns in three selected districts of north Gondar zone, Gondar Ethiopia.
BACKGROUND
Small ruminants are the most numerous of man's domestic livestock. Although sheep represent a great resource for Ethiopia, the net rate of productivity per animal is very low due to many factors including respiratory disorders.
OBJECTIVES
The objectives of this work were to isolate and identify M. haemolytica and P. multocida as well as to assess the antibiotic susceptibility patterns of these isolates. Nasal swab samples were collected aseptically by using 70% alcohol as a disinfectant.
METHODS
A cross-sectional study was conducted in three selected districts of the north Gondar zone, Ethiopia.
RESULTS
From 148 samples collected in 94 (63.5%) asymptomatic and 54 (35.5%) symptomatic sheep, a total of 23 were isolated successfully based on cultural, staining, and biochemical characteristics. Of these isolates, 18 (78.3%) and 5 (21.7%) were M. haeimolytica and P. multocida, respectively. Compared with the total animals examined, the proportion of M. haeimolytica and P. multocida were 12.16 % (n = 18) and 3.38% (n = 5), respectively. All of the isolates were subjected to a panel of 8 antibiotic discs for sensitivity testing. Of the tested antibiotics, chloramphenicol (100%), gentamicin, and tetracycline (82.6%) each and co-trimoxazole (60.8%) were found to be the most effective drugs whereas, both species were completely resistant to vancomycin and showed a very low degree of susceptibility for the rest drugs.
CONCLUSIONS
In conclusion, M. haemolytica was found to be the predominant isolate in all host-related factors and most of the antibiotics were not fully effective against the isolates. Hence, treatment and/or vaccination of ovine pneumonic pasteurellosis should be emphasised to M. haeimolytica using the most effective drugs along with appropriate herd management practices.
Topics: Sheep; Animals; Mannheimia haemolytica; Pasteurella multocida; Ethiopia; Cross-Sectional Studies; Anti-Bacterial Agents
PubMed: 37197762
DOI: 10.1002/vms3.1166 -
Animals : An Open Access Journal From... May 2023is one of the major causes of bovine respiratory disease in cattle. The organism is the primary bacterium isolated from calves and young cattle affected with enzootic...
is one of the major causes of bovine respiratory disease in cattle. The organism is the primary bacterium isolated from calves and young cattle affected with enzootic pneumonia. Novel indirect ELISAs were developed and evaluated to enable quantification of antibody responses to whole cell antigens using A1 strain P1148. In this study, the ELISAs were initially developed using sera from both -culture-free and clinically infected cattle, then the final prototypes were tested in the validation phase using a larger set of known-status sera ( = 145) collected from feedlot cattle. The test showed good inter-assay and intra-assay repeatability. Diagnostic sensitivity and specificity were estimated at 91% and 87% for IgG at a cutoff of S/P ≥ 0.8. IgM diagnostic sensitivity and specificity were 91% and 81% at a cutoff of sample to positive (S/P) ratio ≥ 0.8. IgA diagnostic sensitivity was 89% whereas specificity was 78% at a cutoff of S/P ≥ 0.2. ELISA results of all isotypes were related to the diagnosis of respiratory disease and isolation of (-value < 0.05). These data suggest that ELISAs can be adapted to the detection and quantification of antibody in serum specimens and support the use of these tests for the disease surveillance and disease prevention research in feedlot cattle.
PubMed: 37174567
DOI: 10.3390/ani13091531 -
Vaccine May 2023Bovine respiratory disease is the greatest threat to calf health. In this study, colostrum-fed dairy X beef calves were vaccinated at ∼30 days of age with an...
Bovine respiratory disease is the greatest threat to calf health. In this study, colostrum-fed dairy X beef calves were vaccinated at ∼30 days of age with an adjuvanted parenteral vaccine containing modified live bovine viral diarrhea virus (BVDV) type 1 and type 2, bovine herpesvirus 1 (BHV-1), bovine parainfluenza type 3 virus (PI3V) and bovine respiratory syncytial virus (BRSV) andM. haemolyticatoxoid (Group 1), or intranasal temperature-sensitive BHV-1, BRSV and PI3V concurrently witha parenteral vaccine containing modified live BVDV type 1 and type 2 andM. haemolyticatoxoid (Group 2) or a placebo (Group 3). The calves were challenged ∼150 days post vaccination intranasally with BVDV 1b and then 7 days later intratracheally withM. haemolytica. The calves wereeuthanized 6 days after theM. haemolyticachallenge. Clinical signs following BVDV infection were similar in all groups. There was increased rectal temperatures in the Groups 2 and 3 on day 3 and in Group 3 on days 8-13. Group 1 animals had a slight leukopenia following BVDV infection while Groups 2 and 3 had greater leukopenia. BVDV type 1 and 2 serum titers increased in Group 1 following vaccination while these titers waned in Groups 2 and 3. There were higher levels of BVDV in the buffy coats and nasal samples in Group 2 and Group 3 versus Group 1 (p < 0.01). Interferon-gamma response was higher (p < 0.01) in Group 1 animals than Groups 2 and 3. Group 1 had the lowest percent pneumonic tissue (1.6%) while Group 2 vaccinates had 3.7% and the control Group 3 was 5.3%. Vaccination in the face of maternal antibody with a parenteral adjuvanted vaccine resulted in better protection than the regimen of an intranasal vaccine anda parenteral adjuvanted BVDV andM haemolyticacombination vaccine in a BVDV-M. haemolyticadual challenge.
Topics: Animals; Cattle; Bovine Virus Diarrhea-Mucosal Disease; Antibodies, Viral; Diarrhea Viruses, Bovine Viral; Cattle Diseases; Diarrhea Virus 1, Bovine Viral; Vaccination; Respiratory Tract Diseases; Herpesvirus 1, Bovine; Diarrhea; Leukopenia; Mannheimia; Viral Vaccines
PubMed: 37045678
DOI: 10.1016/j.vaccine.2023.04.005 -
Australian Veterinary Journal Jun 2023Bovine respiratory disease (BRD) has been identified as the most significant infectious disease of feedlot cattle in eastern Australia. Bovine respiratory disease causes... (Review)
Review
Bovine respiratory disease (BRD) has been identified as the most significant infectious disease of feedlot cattle in eastern Australia. Bovine respiratory disease causes economic loss due to medication costs, mortalities, excessive feed inputs associated with increased time on feed, reduced sale prices and associated labour costs. Bovine respiratory disease is a complex multifactorial condition with multiple animal, environmental and management risk factors predisposing cattle to illness. A range of microorganisms are implicated in BRD with at least four viral and five bacterial species commonly involved individually or in combination. The viruses most commonly associated with BRD in Australia are bovine herpesvirus 1 (BHV1), bovine viral diarrhoea virus (BVDV or bovine pestivirus), bovine parainfluenza 3 virus (PI3) and bovine respiratory syncytial virus (BRSV). More recently, bovine coronavirus has been identified as a potential viral contributor to BRD in Australia. A number of bacterial species have also been recognised as important to the BRD complex; these include Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Trueperella pyogenes and Mycoplasma bovis. Although one or more of the pathogens listed above can be isolated from clinical cases of BRD, there is no evidence that infection alone causes serious illness. This indicates that, in addition to specific infectious agents, other factors are crucial for the development of BRD under field conditions. These can be categorised as environmental, animal and management risk factors. These risk factors are likely to exert their effects through multiple pathways including reductions in systemic and possibly local immunity. For example, stressors such as weaning, handling at saleyards, transport, dehydration, weather conditions, dietary changes, comingling and pen competition might reduce the effectiveness of the immune system. Reduced immunocompetence can allow opportunistic infection of the lower airways with potential pathogens leading to the development of BRD. The objective of this paper is to critically review the evidence for management practices aimed at reducing the incidence of BRD in Australian feedlot cattle. Predisposing factors (Table 1) largely beyond the control of most feedlots, such as weather and exposure to respiratory viruses, are discussed separately, but these factors can generate indirect prevention responses that are discussed under the preventative practices categories. The current practices are classified as either animal preparation practices (Table 2) or feedlot management practices (Table 3).
Topics: Animals; Cattle; Australia; Bovine Respiratory Disease Complex; Cattle Diseases; Diarrhea Viruses, Bovine Viral; Incidence; Mannheimia haemolytica
PubMed: 36999220
DOI: 10.1111/avj.13239 -
Australian Veterinary Journal May 2023The objective of this study was to evaluate the passive transfer of maternal antibodies to calves following vaccination of pregnant cows with an inactivated Mannheimia...
Confirmation of the passive transfer of maternal antibodies to calves following vaccination of pregnant cows with an inactivated Mannheimia haemolytica and Bovine herpes virus type 1 vaccine.
The objective of this study was to evaluate the passive transfer of maternal antibodies to calves following vaccination of pregnant cows with an inactivated Mannheimia haemolytica (MH) and Bovine herpes virus type 1 (IBR) vaccine (Bovilis® MH + IBR). Sixty-two pregnant cows were allocated at random to two groups; one group was retained as a negative control group (T01), while the other group (T02) was vaccinated with Bovilis® MH + IBR on two occasions during their third trimester of pregnancy. Following calving, blood samples were collected from calves for the measurement of serum antibody titres to IBR and MH, with samples collected prior to suckling (Day 0) and on days 5 (±2), 14 (±3), 28, 56, 84, 112, 140, 168, 196, 224, 252 and 280. The group mean IBR blocking percentage remained low for T01 calves (calves born to T01 cows) between days 0 and 224 (range 4.5%-15.4%), while the group mean IBR blocking percentage increased for T02 calves (calves born to T02 cows) from 14.3% on Day 0 to 94.9% on Day 5 and remained significantly higher than T01 calves up until Day 252. The group mean MH titre (Log2) for T01 calves increased after suckling to 8.9 on Day 5, before declining and remaining stable (range 5.0-6.5). The group mean MH titre for T02 calves increased after suckling to 13.6 on Day 5 and then gradually declined; however, it remained significantly higher than T01 calves between days 5 and 140. Outcomes from this study have confirmed that colostral transfer of IBR and MH antibodies to newborn calves was successful and a high level of passive immunity was acquired by calves.
Topics: Pregnancy; Female; Cattle; Animals; Mannheimia haemolytica; Vaccination; Herpesvirus 1, Bovine; Antibodies, Viral; Cattle Diseases; Viral Vaccines
PubMed: 36975715
DOI: 10.1111/avj.13236