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Pathogens (Basel, Switzerland) Jan 2024The role of in the development of pulmonary disease in cattle is controversial and was never evaluated in cattle from Latin America. This study investigated the...
The role of in the development of pulmonary disease in cattle is controversial and was never evaluated in cattle from Latin America. This study investigated the respiratory infection dynamics associated with in suckling calves from 15 dairy cattle herds in Southern Brazil. Nasal swabs were obtained from asymptomatic ( = 102) and calves with clinical manifestations ( = 103) of bovine respiratory disease (BRD) and used in molecular assays to identify the specific genes of viral and bacterial disease pathogens of BRD. Only , bovine coronavirus (BCoV), ovine gammaherpesvirus 2 (OvGHV2), , , and were detected. was the most frequently diagnosed pathogen in diseased (57.8%; 59/102) and asymptomatic (55.3%; 57/103) calves at all farms. BCoV-related infections were diagnosed in diseased (52%; 53/102) and asymptomatic (51.4%; 53/103) calves and occurred in 93.3% (14/15) of all farms. Similarly, infectious due to OvGHV2 occurred in diseased (37.2%; 38/102) and asymptomatic (27.2%; /28/103) calves and were diagnosed in 80% (12/15) of all farms investigated. Significant statistical differences were not identified when the two groups of calves were compared at most farms, except for infections due to OvGHV2 that affected five calves at one farm. These results demonstrated that the respiratory infection dynamics of identified in Southern Brazil are similar to those observed worldwide, suggesting that there is not enough sufficient collected data to consider as a pathogen of respiratory infections in cattle. Additionally, the possible roles of BCoV and OvGHV2 in the development of BRD are discussed.
PubMed: 38392852
DOI: 10.3390/pathogens13020114 -
Antibiotics (Basel, Switzerland) Jan 2024Antimicrobial resistance (AMR) is considered one of the greatest threats to both human and animal health. Efforts to address AMR include implementing antimicrobial...
Antimicrobial resistance (AMR) is considered one of the greatest threats to both human and animal health. Efforts to address AMR include implementing antimicrobial stewardship programs and introducing alternative treatment options. Nevertheless, effective treatment of infectious diseases caused by bacteria will still require the identification and development of new antimicrobial agents. Eight different natural products were tested for antimicrobial activity against seven pathogenic bacterial species ( sp., sp., sp., sp., sp., sp., sp.). In a first pre-screening, most compounds (five out of eight) inhibited bacterial growth only at high concentrations, but three natural products (celastramycin A [CA], closthioamide [CT], maduranic acid [MA]) displayed activity at concentrations <2 µg/mL against sp. and two of them (CA and CT) also against sp. Those results were confirmed by testing a larger collection of isolates encompassing 64 and 56 field isolates originating from pigs or cattle, which yielded MIC values of 0.5, 0.5, and 2 µg/mL against and 0.5, 4, and >16 µg/mL against for CA, CT, and MA, respectively. CA, CT, and MA exhibited higher MIC and MIC values against isolates with a known AMR phenotype against commonly used therapeutic antimicrobial agents than against isolates with unknown AMR profiles. This study demonstrates the importance of whole-cell antibacterial screening of natural products to identify promising scaffolds with broad- or narrow-spectrum antimicrobial activity against important Gram-negative veterinary pathogens with zoonotic potential.
PubMed: 38391521
DOI: 10.3390/antibiotics13020135 -
Preventive Veterinary Medicine Mar 2024Antimicrobial use (AMU) in the livestock sector is a major driver of antimicrobial resistance. Italian beef industry strongly relies on the import of young cattle from...
Effects of vaccination timing and target pathogens on performances and antimicrobial use in long-transported Charolais beef cattle from France to Italy - A retrospective study.
Antimicrobial use (AMU) in the livestock sector is a major driver of antimicrobial resistance. Italian beef industry strongly relies on the import of young cattle from France, which are commingled in sorting facilities before transportation to Italy. Both commingling and transportation are stressors for animals and lead to higher risk of bovine respiratory disease (BRD), which in turn increases the risk of AMU. This study aimed to investigate how the timing of first BRD vaccination and the different vaccination target pathogens affect AMU and performance of young Charolais beef cattle imported from France to Italy. Information on animal performance, antimicrobial treatments, and vaccinations was available for 60,726 Charolais cattle belonging to 1449 batches in 33 Italian specialised fattening farms between January 2016 and December 2021. Antimicrobial use was estimated using the treatment incidence 100 adapted for Italy (TI100it). A mixed linear model was used to quantify the effects of the vaccination and the time of first administration on slaughter age, carcase weight, and average daily carcase gain. Similarly, a generalised linear mixed model was used to analyse the TI100it. The vaccination programme was usually applied the first day after the animals' arrival to the Italian fattening farms. Most animals were vaccinated with a polyvalent vaccine against infectious bovine rhinotracheitis (IBR), bovine parainfluenza type 3 virus (PI-3), bovine viral diarrhoea virus type 1 and 2 (BVDV), and bovine respiratory syncytial virus (BRSV). The most used class of antimicrobials to treat BRD were the macrolides, followed by aminoglycosides, amphenicols, tetracyclines, aminopenicillins, and fluoroquinolones. Animals that got vaccinated against any of the considered BRD pathogens upon arrival had significantly lower TI100it, greater average daily carcase gain, and reached slaughter age earlier than animals that got vaccinated later. Animals that received the vaccination against BVDV had lower TI100it and greater average daily carcase gain, and animals that received the vaccination against BRSV were younger at slaughter than unvaccinated animals. The vaccination against Mannheimia haemolytica significantly decreased the slaughter age and increased the carcase weight and average daily carcase gain, and the vaccination against PI-3 and Histophilus somni significantly increased the slaughter age. Thus, even if the vaccination programme is essential to tackle BRD, this practice is questionable if applied at arrival to the Italian fattening farms and it is advisable that the vaccination programme is planned before the commingling procedure in France.
Topics: Animals; Cattle; Retrospective Studies; Vaccination; Cattle Diseases; Respiratory Tract Diseases; Anti-Bacterial Agents; France
PubMed: 38335832
DOI: 10.1016/j.prevetmed.2024.106130 -
PloS One 2024Mannheimia haemolytica is the principal agent contributing to bovine respiratory disease and can form biofilms with increased resistance to antibiotic treatment and host...
Mannheimia haemolytica is the principal agent contributing to bovine respiratory disease and can form biofilms with increased resistance to antibiotic treatment and host immune defenses. To investigate the molecular mechanisms underlying M. haemolytica biofilm formation, transcriptomic analyses were performed with mRNAs sequenced from planktonic and biofilm cultures of pathogenic serotypes 1 (St 1; strain D153) and St 6 (strain D174), and St 2 (strain D35). The three M. haemolytica serotypes were cultured in two different media, Roswell Park Memorial Institute (RPMI) 1640 and brain heart infusion (BHI) to form the biofilms. Transcriptomic analyses revealed that the functions of the differentially expressed genes (DEGs) in biofilm associated cells were not significantly affected by the two media. A total of 476 to 662 DEGs were identified between biofilm associated cells and planktonic cells cultured under BHI medium. Functional analysis of the DEGs indicated that those genes were significantly enriched in translation and many biosynthetic processes. There were 234 DEGs identified in St 1 and 6, but not in St 2. The functions of the DEGs included structural constituents of ribosomes, transmembrane proton transportation, proton channels, and proton-transporting ATP synthase. Potentially, some of the DEGs identified in this study provide insight into the design of new M. haemolytica vaccine candidates.
Topics: Animals; Cattle; Mannheimia haemolytica; Plankton; Protons; Biofilms; Cattle Diseases; Gene Expression Profiling
PubMed: 38329985
DOI: 10.1371/journal.pone.0297692 -
International Journal of Molecular... Jan 2024Respiratory diseases in ruminants are a main cause of economic losses to farmers worldwide. Approximately 25% of ruminants experience at least one episode of respiratory...
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. is the main etiological bacterial agent in the ruminant respiratory disease complex. 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 A2 proteases and their host protein targets. Here, we obtained evidence that 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.
Topics: Cattle; Sheep; Animals; Mannheimia haemolytica; Pasteurellosis, Pneumonic; Metalloproteases; Peptide Hydrolases; Ruminants; Collagenases; Zinc; Sheep Diseases
PubMed: 38279292
DOI: 10.3390/ijms25021289 -
Animals : An Open Access Journal From... Jan 2024(1) Background: () is an opportunistic pathogen and is mainly associated with respiratory diseases in cattle, sheep, and goats. (2) Methods: In this study, a mouse...
(1) Background: () is an opportunistic pathogen and is mainly associated with respiratory diseases in cattle, sheep, and goats. (2) Methods: In this study, a mouse infection model was established using a strain isolated from goats. Histopathological observations were conducted on various organs of the mice, and bacterial load determination and RNA-seq analysis were specifically performed on the spleens of the mice. (3) Results: The findings of this study suggest that chemokines, potentially present in the spleen of mice following a challenge, may induce the migration of leukocytes to the spleen and suppress the release of pro-inflammatory factors through a negative feedback regulation mechanism. Additionally, an interesting observation was made regarding the potential of hematopoietic stem/progenitor cells congregating in the spleen to differentiate into immune cells, which could potentially collaborate with leukocytes in their efforts to counteract invasion. (4) Conclusions: This study revealed the immune regulation mechanism induced by in the mouse spleen, providing valuable insights into host-pathogen interactions and offering a theoretical basis for the prevention, control, and treatment of mannheimiosis.
PubMed: 38275777
DOI: 10.3390/ani14020317 -
Antibiotics (Basel, Switzerland) Jan 2024Weaned dairy heifers are a relatively understudied production group. Bovine respiratory disease (BRD) is the most common cause of antimicrobial drug (AMD) use,...
Weaned dairy heifers are a relatively understudied production group. Bovine respiratory disease (BRD) is the most common cause of antimicrobial drug (AMD) use, morbidity, and mortality in this production group. The study of antimicrobial resistance (AMR) is complicated because many variables that may affect AMR are related. This study generates hypotheses regarding the farm- and animal-level variables (e.g., vaccination, lane cleaning, and AMD use practices) that may be associated with AMR in respiratory isolates from weaned dairy heifers. A cross-sectional study was performed using survey data and respiratory isolates (, , and ) collected from 341 weaned dairy heifers on six farms in California. Logistic regression and Bayesian network analyses were used to evaluate the associations between farm- and animal-level variables with minimum inhibitory concentration (MIC) classification of respiratory isolates against 11 AMDs. Farm-level variables associated with MIC classification of respiratory isolates included the number of source farms of a calf-rearing facility, whether the farm practiced onsite milking, the use of lagoon water for flush lane cleaning, and respiratory and pinkeye vaccination practices. Animal-level variables associated with a MIC classification included whether the calf was BRD-score-positive and time since the last phenicol treatment.
PubMed: 38247609
DOI: 10.3390/antibiotics13010050 -
JDS Communications Jan 2024Accurate isolation and identification of pathogens for an animal with bovine respiratory disease are of critical importance to direct appropriate decision-making related...
Accurate isolation and identification of pathogens for an animal with bovine respiratory disease are of critical importance to direct appropriate decision-making related to the treatment of individual animals, as well as control and prevention options in a herd setting. The objective of this study was to compare nasopharyngeal sampling approaches to evaluate accuracy and agreement for the recovery of (MH) and (PM) from deep nasopharyngeal swabs (DNS) using 3 different swabs. Deep nasopharyngeal samples were collected from 45 dairy calves using 3 swabs: (1) double-guarded culture swab (DGS); (2) single-guarded culture swab (SGS); and (3) unguarded culture swab (UGS). To evaluate the degree of agreement between DGS, SGS, and UGS, culture results were compared for each calf sampled by using a kappa agreement test. Overall, findings from our study support that when using either SGS or DGS for DNS sampling of preweaning calves, a high agreement for recovery of PM is observed. A low recovery of MH was observed in the study, limiting the conclusion comparing the 3 DNS methods. Use of UGS is considered a potential alternative; however, a higher percentage of polymicrobial growth was found with UGS samples.
PubMed: 38223385
DOI: 10.3168/jdsc.2023-0425 -
Scientific Reports Jan 2024Five essential oils (EOs) were previously characterized in vitro and identified as candidate EOs for the development of an intranasal EO spray to mitigate bovine...
A single intranasal dose of essential oil spray confers modulation of the nasopharyngeal microbiota and short-term inhibition of Mannheimia in feedlot cattle: a pilot study.
Five essential oils (EOs) were previously characterized in vitro and identified as candidate EOs for the development of an intranasal EO spray to mitigate bovine respiratory disease (BRD) pathogens. In the present study, these EOs were evaluated for their potential to (i) reduce BRD pathogens, (ii) modulate nasopharyngeal microbiota, and (iii) influence animal performance, feeding behavior and immune response when a single dose administered intranasally to feedlot cattle. Forty beef steer calves (7-8 months old, Initial body weight = 284 ± 5 kg [SE]) received either an intranasal EO spray (ajowan, thyme, fennel, cinnamon leaf, and citronella) or PBS (Control; n = 20/group) on day 0. Deep nasopharyngeal swabs were collected on days (d) -1, 1, 2, 7, 14, 28, and 42 and processed for 16S rRNA gene sequencing, qPCR, and culturing. Significant effects of EO on community structure (d1), microbial richness and diversity, relative abundance of some dominant phyla (d1, d2, and d14), and the overall interaction network structure of the nasopharyngeal microbiota were detected. The relative abundance of Mannheimia was lower in the EO calves (4.34%) than in Control calves (10.4%) on d2, and M. haemolytica prevalence on d7 as compared to control calves. Feed intake, average daily gain, feeding behavior, and blood cell counts were not affected by EO treatment. Overall, a single intranasal dose of EO spray resulted in moderate modulation of nasopharyngeal microbiota and short-term inhibition of Mannheimia while not influencing animal performance, feeding behavior or immune response. Our study, for the first time, shows the potential use of intranasal EO to mitigate BRD in feedlot cattle.
Topics: Cattle; Animals; Pilot Projects; Mannheimia; RNA, Ribosomal, 16S; Microbiota; Oils, Volatile
PubMed: 38191803
DOI: 10.1038/s41598-023-50704-1 -
Veterinary Medicine (Auckland, N.Z.) 2023Pneumonic pasteurellosis is a respiratory system disease of sheep caused by , and responsible for the low productivity and economic loss resulting from death and...
Isolation and Molecular Detection of and from Clinically Pneumonic Pasteurellosis Cases of Bonga Sheep Breed and Their Antibiotic Susceptibility Tests in Selected Areas of Southwest Ethiopian Peoples Regional State, Ethiopia.
BACKGROUND
Pneumonic pasteurellosis is a respiratory system disease of sheep caused by , and responsible for the low productivity and economic loss resulting from death and treatment costs. This study was conducted to isolate and molecularly detect causative agents and antibiotic susceptibility tests from a nasal swab sample of the Bonga sheep breed that was suspected to have pneumonic pasteurellosis in selected areas of Southwest Ethiopian Peoples Regional State.
METHODS
A cross-sectional study design was used along with purposive sampling of nasal swab samples from sheep that were brought to veterinary clinics during the study period. Bacterial isolation and phenotypic characterization were carried out using microbiological and biochemical tests that followed standard microbiological techniques. To molecularly confirm the isolates, and , species-specific PCR primer genes were used. Using the disc diffusion method, molecularly confirmed isolates were subjected to an in vitro antibiotic susceptibility test.
RESULTS
The 85 samples that were scrutinized had an overall isolation rate of 31.76%, whereas the isolates of and had species compositions of 40.7% and 59.25%, respectively. Overall, 12.5% of the and 18.18% of the species were verified from phenotypical isolates using the species-specific PCR primer genes and , respectively. An in vitro antibiotic susceptibility test was carried out on all four PCR-confirmed isolates for seven commonly used antibiotics used to treat ovine pasteurellosis in the study area. It was found that both bacterial species were resistant to chloramphenicol and penicillin G.
CONCLUSION
Using phenotypic and molecular diagnostic techniques, the results of our current inquiry revealed that and are the causative agents of ovine pneumonic pasteurellosis in the study area.
PubMed: 38162823
DOI: 10.2147/VMRR.S435932