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Mannheimia haemolytica is recognized as principal pathogen associated with pneumonic pasteurellosis leading to huge economic losses to small ruminant farmers. Even though the disease causes huge economic losses, epidemiology of M. haemolytica is less studied, hindering the formulation of effective control strategies. Current study aimed to highlight molecular characterisation of M. haemolytica strains isolated from ovine pneumonic infection. M. haemolytica 27 isolates with two reference strains were characterised using capsular and virulence gene typing, multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) methods. M. haemolytica serotype A2 recognized as predominant serotype (74%) followed by A6 (11%) and A1 (5%) serotypes. Virulence gene profiling by PCRs showed dominance of all five virulent genes [such as adh and gcp (100% each)] followed by gs60 (88.8%), lktC (85.2%), tbpB (51.9%) and least nmaA gene (14.8%). MLST profiling delineated M. haemolytic isolates into 11 sequence types (STs) with most prevalent being ST37 (27.9%) and ST16 (23%) and nine new STs (ST37, 38, 39, 40, 41, 42, 47, 48, and 49). These new STs did not belong to any of the three clonal complexes (CC4, CC8 and CC28). ST16 was exclusively noted in A1 and A6 serotypes. Amongst 25 isolates, 22 pulsotypes (GD 0.88) recorded indicated variability of the M. haemolytica isolates in PFGE analysis. In conclusion, the study suggested dominance of M. haemolytica serotype A2 harbouring different virulent genes, diverse STs and pulsotypes responsible for pneumonic pasteurellosis frequently encountered in sheep. [ABSTRACT FROM AUTHOR]

• Elevation, land surface temperature, host variables (Cattle, Buffalo and Pigs) determine the spatial risk of Anthrax in Karnataka state of India • Response curves for selected predictor variables developed using Bayesian Penalised spline method • Risk map for Anthrax developed using remote sensed variables • Risk map will be helpful in planning future surveillance, prevention and control Anthrax is an economically important livestock disease affecting subsistence farmers and it is of zoonotic importance. Anthrax is endemic in many states of India including Karnataka. Identification of spatial risk factors for occurrence of anthrax and development of predictive risk maps are required for planning adequate vaccination in high-risk areas as well as targeted surveillance activities in animals, humans and environment. In this study, village level anthrax outbreak locations from Karnataka (1997-2016) were geo-referenced and predictive risk map was developed using temporally Fourier Processed remotely sensed variables. A non-linear discriminant analysis approach was used to develop the risk map for Karnataka. Elevation was identified as top predictor variable in the 10 variables selected. The predicted risk map showed good accuracy and validation statistics when evaluated using different metrics (Kappa, sensitivity, specificity, AUC). The predicted risk map also showed good correspondence with past outbreaks. Further, we used Bayesian Penalised spline method to estimate species response curves for top 10 variables selected. The validated risk map can be used in planning vaccination strategy and surveillance in high-risk areas. Risk map for Anthrax in Karnataka using Fourier processed MODIS variables. The probability of suitability is on a scale from zero to one. [Display omitted] [ABSTRACT FROM AUTHOR]

• Whole genome sequencing of Indian virulent Pasteurella multocida B:2 strains. • Comparative genome analysis of Haemorrhagic septicaemia (HS) causing P. multocida B:2 strains of bovines. • A high divergence of SNPs among circulating P. multocida strains. • Virulent field strains differ from existing HS vaccine strain in India. Pasteurella multocida , a Gram-negative bacterium with ubiquitous nature, is known to affect wide range of host species worldwide with varied clinical manifestations including haemorrhagic septicaemia (HS) in bovines. Although, HS causing P. multocida strains were identified and characterized by conventional tools and PCR assays, diverse strains are indistinguishable by these tools in the face of disease outbreaks. In this study, draft genomes of three virulent P. multocida serotype B:2 strains (NIVEDIPm32, NIVEDIPm34 and NIVEDIPm35) were analyzed following whole genome sequencing, assembly, annotation and compared them with existing global genomes (n = 43) of bovine origin in the database. Three draft genomes of NIVEDIPm strains consisted of 40–52 contigs with GC content of ∼40.4%. The genome size and predicted genes content was ∼2.3 Mb and 2181–2189, respectively. Besides, the presence of various mobile genetic elements, antimicrobial resistance genes and biofilm related genes suggested their vital roles in virulence; further, adaptation to the host immune system as well as host pathogen interaction. Multi locus sequence analysis based on RIRDC scheme showed the presence of ST122 in all the three strains. wgMLST based phylogenic analysis suggested that HS causing Indian virulent field strains differed geographically and showed diversity from existing HS vaccine strain P52. The phylogenetic tree revealed that North Indian strains share high similarity with strains of Pakistan than South Indian Strain. Notably, a high divergence of SNPs between the HS causing circulating virulent strains of India and current HS vaccine strain P52 suggested an imminent need for relook in to HS vaccination strategy for livestock in India. [ABSTRACT FROM AUTHOR]

Background and Aim: Respiratory infection due to Mannheimia haemolytica and Pasteurella multocida are responsible for huge economic losses in livestock sector globally and it is poorly understood in ovine population. The study aimed to investigate and characterize M. haemolytica and P. multocida from infected and healthy sheep to rule out the involvement of these bacteria in the disease. Materials and Methods: A total of 374 healthy and infected sheep samples were processed for isolation, direct detection by multiplex PCR (mPCR), and antibiotic susceptibility testing by phenotypic and genotypic methods. Results: Overall, 55 Pasteurella isolates (27 [7.2%] M. haemolytica and 28 [7.4%] P. multocida) were recovered and identified by bacteriological tests and species-specific PCR assays. Significant correlation between the detection of M. haemolytica (66.6%) with disease condition and P. multocida (19.1%) exclusively from infected sheep was recorded by mPCR. In vitro antibiotic susceptibility testing of 55 isolates revealed higher multidrug resistance in M. haemolytica (25.9%) than P. multocida (7.1%) isolates. Descending resistance towards penicillin (63.6%), oxytetracycline (23.6%), streptomycin (14.5%), and gentamicin (12.7%) and absolute sensitivity towards chloramphenicol were observed in both the pathogens. The antibiotic resistance genes such as strA (32.7%) and sul2 (32.7%) associated with streptomycin and sulfonamide resistance, respectively, were detected in the isolates. Conclusion: The study revealed the significant involvement of M. haemolytica together with P. multocida in ovine respiratory infection and is probably responsible for frequent disease outbreaks even after vaccination against hemorrhagic septicemia in sheep population of Karnataka, southern province of India. [ABSTRACT FROM AUTHOR]

India has 9 million pigs, of which 45% are in the North eastern (NE) states of India. Viral diseases affecting pigs are a major concern of mortality causing huge loss to the pig farmers. One such disease is African swine fever (ASF) that has already knocked the porous borders of NE states of India. ASF is a highly contagious devastating disease of pigs and wild boars causing 100% mortality. The causative agent African swine fever virus (ASFV) belongs to the genus Asfivirus, family Asfarviridae. Pig is the only species affected by this virus. Soft ticks (Ornithodoros genus) are shown to be reservoir and transmission vectors of ASFV. Transmission is very rapid and quickly engulfs the entire pig population. It is very difficult to differentiate classical swine fever from ASF since clinical symptoms overlap. Infected and in contact pigs should be culled immediately and buried deep, and sheds and premises be disinfected to control the disease. There is no vaccine available commercially. Since its first report in Kenya in 1921, the disease has been reported from the countries in Europe, Russian federation, China, and Myanmar. The disease is a threat to Indian pigs. OIE published the first report of ASF in India on May 21, 2020, wherein, a total of 3701 pigs died from 11 outbreaks (Morbidity - 38.45% and mortality - 33.89%) in Assam and Arunachal Pradesh states of India. ASF is non-zoonotic. [ABSTRACT FROM AUTHOR]

Haemorrhagic septicaemia (HS) is an economically important disease affecting cattle and buffaloes and the livelihoods of small-holder farmers that depend upon them. The disease is caused by Gram-negative bacterium, Pasteurella multocida, and is considered to be endemic in many states of India with more than 25,000 outbreaks in the past three decades. Currently, there is no national policy for control of HS in India. In this study, we analysed thirty year (1987-2016) monthly data on HS outbreaks using different statistical and mathematical methods to identify spatial variability and temporal patterns (seasonality, periodicity). There was zonal variation in the trend and seasonality of HS outbreaks. Overall, South zone reported maximum proportion of the outbreaks (70.2%), followed by East zone (7.2%), Central zone (6.4%), North zone (5.6%), West zone (5.5%) and North-East zone (4.9%). Annual state level analysis indicated that the reporting of HS outbreaks started at different years independently and there was no apparent transmission between the states. The results of the current study are useful for the policy makers to design national control programme on HS in India and implement state specific strategies. Further, our study and strategies could aid in implementation of similar approaches in HS endemic tropical countries around the world., (© 2024. The Author(s).)