Mycobacterium Avium Subspecies Paratuberculosis Research Articles

IP10 is a predictor of successful vaccine protection against paratuberculosis infection in sheep.

The cell mediated immune response and ability of immune cells to migrate to the site of infection are both key aspects of protection against many pathogens. Mycobacterium avium subsp. paratuberculosis (MAP) is an intracellular pathogen and the causative agent of paratuberculosis, a chronic wasting disease of ruminants. Current commercial vaccines for paratuberculosis reduce the occurrence of clinical disease but not all animals are protected from infection. Therefore, there is a need to understand the immune responses triggered by these vaccines at the site of infection, in circulating immune cells and their relationships to vaccine-mediated protection. The magnitude and location of gene expression related to the cell mediated immune response and cellular migration were studied in the ileum of sheep. In addition, longitudinal IP10 (also known as IP10) secretion by circulating immune cells was examined in the same sheep. Animals were grouped based on vaccination status (vaccinated vs non-vaccinated) and MAP exposure (experimentally exposed vs unexposed). Vaccination of unexposed sheep increased the expression of IP10, CCL5 and COR1c. Sheep that were successfully protected by vaccination (uninfected following experimental exposure) had significantly reduced expression of IP10 in the ileum at 12months post exposure compared to vaccine non-responders (those that became infected) and non-vaccinated infected sheep. Successfully protected sheep also had significantly increased secretion of IP10 in in vitro stimulated immune cells from whole blood compared to vaccine non responders at 4months post exposure. Therefore, the IP10 recall response has the potential to be used as marker for infection status in vaccinated sheep and could be a biomarker for a DIVA test in sheep.

Paratuberculose clínica bovina: primeiro relato no estado do Pará

ABSTRACT The objective of this work was to describe the clinical, pathological, and serological aspects of paratuberculosis in a bullock on dairy and beef farm in the municipality of Inhangapí, state of Pará. The animal was raised extensively and presented progressive weight loss, pale mucous membranes, and chronic diarrhea. A blood sample was collected for serology by the indirect ELISA technique. Due to the unfavorable prognosis, the animal was euthanized and necropsied. At necropsy, there was thickened and wrinkled intestinal mucosa, enlarged mesenteric lymph nodes and liquid intestinal contents with a brown color. Organ fragments were fixed in 10% buffered formaldehyde, embedded in paraffin wax, cut, and stained by hematoxylin and eosin and by Ziehl-Neelsen techniques. Histopathology showed intense granulomatous infiltration with Langhans giant cells in the lamina propria and submucosa of the small intestine, Peyer patches and mesenteric lymph nodes. Ziehl-Neelsen staining revealed many intralesional acid-fast bacilli. Antibody searching against Mycobacterium avium (subsp.) paratuberculosis was positive. The diagnosis of paratuberculosis was based on epidemiological, clinical, pathological, and serological data. This is the first report of clinical paratuberculosis, confirmed by pathology and serology, in a bullock in the state of Pará.

Crohn's Disease: Retrospective Study In Algerian Patients

Background: Inflammatory disease of Crohn affects the entire digestive tract, with extra-intestinal manifestations and immune disorders.
 Objectives: This work aims to represent the histopathological aspects of Crohn‘s disease and the establishment of pathogenic bacteria as causal agents.
 Methodology: The histopathological aspects of the disease were studied on a colonic resection specimen and on intestinal biopsies with colorations topographic staining. Pathogenic bacteria responsible for Crohn‘s disease have also been isolated and identified. The study is continued to establish a correlation between the disease and exposure to infections by unusual bacteria, particularly pathogens (Salmonella, Shigella, Streptococcus pyogenes, Klebsiella).
 Results : The macroscopic appearance of the disease presented transmural involvement and can be complicated by abscesses and fistulas, microscopic appearance indicated the infiltrate of inflammatory cells (lymphocytes, plasma and cells) and lymphoid follicles after topographic staining.
 Crohn’s disease is an idiopathic disease, it is assumed that it is a deregulation of the immune system due to an infectious agent in genetically predisposed people.
 In our work, we studied the microbiota of intestine and stool of Crohn’s patients in which we found certain bacteria including Proteus mirabilis with a predominance of E. coli. Other pathogenic bacteria were found like Salmonella spp., Shigella spp., Klebsiella spp. and Streptococcus pyogenes. Two cases which tested positive on Ziehl Neelsen stain represented Mycobacterium avium paratuberculosis.
 Conclusion: The histopathological aspect of CD can be better visualized and identified on surgical specimens than on endoscopic biopsies, which helps to monitor the evolution of the disease and must be accompanied by clinical, serological and radiological exploration.

First report of paratuberculosis (Johne's disease) in livestock farms of river buffaloes (Bubalus Bubalis) in Nineveh, Iraq.

The present study was designed to investigate Mycobacterium avium subsp. paratuberculosis (MAP) in dairy buffalo herds from six different geographical areas in Nineveh, Iraq. A total of 87 individual faecal samples from river buffaloes, representing 12 dairy herds, were investigated for detection of MAP using cultural, Ziehl‑Neelsen and MAP‑specific PCR‑based methods. Overall, MAP was detected at a higher frequency at herd‑level (4/12; 33%) compared to the total individual faecal samples (14/87; 16%) with a cell density ranging from 101 to 103 CFU g‑1. A significantly (p < 0.05) higher frequency (9/17; 53%) of MAP was observed in faecal samples collected from clinically diseased as compared to healthy (5/70; 7%) buffaloes selected for the study. However, no statistically significant difference (p ≥ 0.05) was observed in the frequency of MAP occurrence between clinical (9; 64%) and apparently healthy (5; 36%) cases. This report, which is the first MAP study based on data from Iraqi dairy buffalo herds suggests that MAP transmission is a significant health risk for grazing livestock. In conclusion, this study would help farm owners and regulatory authorities to realise the importance of developing and applying best farm management practices in order to prevent transmission of MAP to healthy animals and the environment. In addition, effective diagnostic tests should be taken into account when carrying out the screening tests.

Ursolic Acid and Solasodine as Potent Anti-Mycobacterial Agents for Combating Paratuberculosis: An Anti-Inflammatory and In Silico Analysis.

Mycobacterium avium subspecies paratuberculosis (MAP) infection in domestic livestock causes persistent diarrhea, weight loss, and death and is also a potential cause of Crohn's disease (CD) in humans; notably, treatments against MAP are insufficient, costly, and can cause adverse reactions. Hence, plant-derived bioactive constituents have been taken into consideration in this regard. Herein, we present the results of two bioactive constituents (Solasodine and Ursolic acid) that were evaluated for their safety and efficacy against MAP protein (Dephospho-Coenzyme A kinase (DPCK) by utilizing in vitro assays and different tools of in silico biology. The ADME/t-test, the drug-likeness property test, pharmacophore modelling, and PASS prediction have proven that both the constituents have better binding capacities than the available antibiotic drugs used to target protein inhibition pathways. Through our observations, it can be inferred that these two phytochemicals can be adequately used to treat paratuberculosis, thereby combating inflammatory bowel disorders (IBD) of an autoimmune nature.

Experimental evidence of the anti-bacterial activity pathway of copper ion treatment on Mycobacterium avium subsp. paratuberculosis.

Copper causes significant damage to the integrity of many bacteria, mainly at the DNA level, through its redox states, as well as its reactive oxygen species (ROS) generating capacity at the cellular level. But whether these mechanisms also apply to Mycobacterium avium subsp. paratuberculosis (MAP) is unknown. In the present study, we have evaluated whether copper ions produce damage at the DNA level of MAP, either through their redox states or through ROS production. MAP-spiked PBS was first supplemented with different copper chelators (2) and ROS antioxidants (3), followed by treatment with copper ions at 942ppm. MAP DNA integrity (qPCR, magnetic phage separation) was then evaluated. We found that bathocuproine (BCS), as a chelator, and D-mannitol, as an antioxidant of hydroxyl radicals, had a significant protective effect (P < 0.05) on DNA molecules, and that EDTA, as a chelator, and D-mannitol, as an antioxidant had a significant positive effect (P < 0.05) on the viability of this pathogen in contrast to the control and other chelators and anti-oxidants used. In light of the reported findings, it may be concluded that copper ions within MAP cells are directly related to MAP DNA damage.

Molecular and serological survey of paratuberculosis in cattle in selected districts of Western Uganda

Knowledge of Mycobacterium avium subsp. paratuberculosis (MAP) herd infection status is important to plan appropriate control and prevention strategies for Paratuberculosis (PTB); however, in Uganda MAP infection status of most herds is unknown. This study aimed at determining the MAP infection status of cattle herds and the associated risk factors for MAP infection in six western districts of Uganda. The survey covered a total of 93 herds where faecal and blood samples were collected from 1814 cattle. A Recombinase Polymerase Amplification (RPA) and an antibody-based (ELISA) assays were used to test for the presence of MAP DNA in faeces and MAP antibodies in serum, respectively. The apparent cow-level prevalence of MAP infection was 3.2 and 2.7% using ELISA and RPA respectively and the true cow-level prevalence using ELISA and RPA was 4.9 and 3% respectively. A herd-level prevalence of 43% (ELISA) and 40.8% (RPA) and a within-herd prevalence of 3.8 ± 2.1% based on ELISA were obtained. Among the risk factors investigated, long dry spells were significantly associated with high MAP infection (p < 0.05). These results indicate that MAP is actively present in most areas where surveillance was carried out. This poses a serious threat to the livestock industry and potentially to public health as MAP is highly suspected to play a role in the pathogenesis of several diseases in humans. Other areas of the country are to be surveyed as well in order to establish full data on MAP infection status to enable interventions for the control and prevention of the disease.

B cell phenotypes and maturation states in cows naturally infected with Mycobacterium avium subsp. Paratuberculosis.

Little is known about the role that B cells play in immune responses to infection with the intracellular pathogen, Mycobacterium avium subsp. paratuberculosis (MAP). Traditionally, the role of B cells has been constrained to their function as antibody-producing cells, however, antibodies are not thought to play a protective role in mycobacterial infections. The present study was designed to characterize B cell subpopulations as well as activation/maturation states in cattle with paratuberculosis. Peripheral blood mononuclear cells (PBMCs) were isolated from noninfected control cows (n = 8); as well cattle naturally infected with MAP in the subclinical (n = 8) and clinical (n = 7) stage of infection and stimulated with MAP antigen for 6 days. MAP infection resulted in greater numbers of total B cells for clinical cows compared to control noninfected cows. The major subpopulation in freshly isolated PBMCs in clinical cows was B-1a B cells, but this shifted to a composite of both B-1a and B-2 B cells upon stimulation of PBMCs with either MAP antigen or pokeweed mitogen, with higher numbers of B-2 B cells. Early B cells were observed to predominate the population of B cells in PBMCs, with lesser populations of germinal B cells, memory B cells and plasma cells. These subpopulations were elevated in clinical cows upon stimulation of PBMCs with MAP antigen, except for plasma cells which were lower compared to control noninfected cows. Increased numbers of B cells in clinical cows aligned with higher expression of B cell markers such as MAPK1/3, BTG1, Bcl2, CD79A and SWAP70, depending upon in vitro stimulation with either mitogen or antigen. This would indicate that the B cells were capable of activation but were anti-apoptotic in nature. The shift to B-2 B cells in the periphery of clinical cows seems to be indicative of an expansion of memory B cells, rather than plasma cells. This may be a last attempt by the host to control the rampant inflammatory state associated with advanced clinical disease.

Isothermal inactivation of Mycobacterium avium subsp. paratuberculosis in curd simulating the stretching phase in pasta-filata cheese process.

Raw milk and dairy products are usually considered the major sources of Mycobacterium avium subsp. paratuberculosis (MAP) exposure for humans. During the production process of mozzarella cheese, as well as of other pasta-filata cheeses made with pasteurized or raw milk, curd is heated and stretched by addition of hot or boiling water. This step is the critical point for the inactivation of MAP during the production process, but, to our knowledge, no studies have been published about the thermal death time values of MAP in curd. The aim of this study was to determine the inactivation kinetics of MAP in curd used to produce pasta-filata cheese in six independent experiments. The milk was inoculated with a mix of MAP strains (field and registered strains) and, with the aim to simulate the thermal treatment of the curd during the stretching step, samples of 10 g of contaminated curd were vacuum packed and treated separately at six different temperatures from 60°C to 75°C in a water bath. MAP survival was then evaluated by plate count method and inactivation parameters were estimated for determining the thermal resistance of the pathogen directly in the curd. D-values increased from 0.15 min (D75-value) to 4.22 min (D60-value) and the calculated z-value was 10.2°C. These data aid: (i) to design food thermal process treatments defining acceptance limits of critical control points to ensure safety against MAP; (ii) to predict the time/temperature combinations needed to obtain a certain MAP log reduction during the curd stretching step; (iii) to optimize or validate pasta-filata cheese process.

Prevalence of Mycobacterium avium Subsp. paratuberculosis in Feral Pigeons (Columba livia) Associated with Difficulties Controlling Paratuberculosis in a Bovine Herd (Fighting Bull Breed).

A bovine herd with a high prevalence of paratuberculosis (PTB) cohabiting with a population of pigeons was studied (2011−2020). After finding the disease in 2011, annual monitoring was performed in 2012−2014 by obtaining blood samples for ELISA and intradermal tuberculinization (IT) tests for Mycobacterium avium subsp. paratuberculosis (MAP). Positive animals were eliminated. PTB prevalence dropped from 10% to 0% but returned to similar values (9.5%) after 6 years without tests. In all animals, Ac values according to the optical density (OD) determined by ELISA increased each year and could be used to isolate herds close to the cutoff point to improve PTB control. Possible reservoirs were considered after evaluating the little success of the PTB control program, and the population of feral pigeons was studied. Specifically, 10% of the pigeon population (n = 13) was necropsied. Samples of intestine, feces, and foot skin for PCR study for MAP and samples of terminal intestine for histopathological analysis were taken. Eleven pigeons were PCR-positive against MAP, in the intestine (10/11), foot skin (3/11), and feces (1/11). The presence of MAP in pigeon feet could demonstrate its role as a mechanical disseminator of PTB, while the presence in pigeon intestine and feces could also suggest its role as a reservoir.

First Evidence of the Presence of the Causative Agent of Caseous Lymphadenitis-Corynebacterium pseudotuberculosis in Dairy Products Produced from the Milk of Small Ruminants.

This study focused on the detection and quantification of selected bacteria and on the presence of enterotoxin genes in milk and dairy products from sheep and goat farms in the Czech Republic using quantitative real-time PCR (qPCR) and multiplex PCR (PCR). The presence of Corynebacterium pseudotuberculosis (CP), Mycobacterium avium subsp. paratuberculosis (MAP), Listeria monocytogenes, Staphylococcus aureus, S. aureus enterotoxin genes and methicillin-resistant Staphylococcus aureus (MRSA) was determined in 18 milk samples, 28 fresh cheeses, 20 ripened cheeses and 14 yoghurts. The serological status of the herds in relation to CP and MAP was taken into account. The most frequently detected bacterium was S. aureus (48.8%), and subsequent PCR revealed 11 MRSA positive samples. The S. aureus enterotoxin genes seg, sei and sec were detected in two goat cheeses. Cheese samples showed a statistically higher risk of SA and MRSA occurrence. CP (8.8%) and MAP (13.8%) were detected by qPCR on two different seropositive farms. Cultivation of qPCR positive CP samples on agar plates supplemented with potassium tellurite showed the presence of viable bacterium. The results obtained confirmed the necessity of monitoring the infectious status of dairy animals and rapid diagnosis of bacterial pathogens in milk and dairy products.

Investigating effective testing strategies for the control of Johne's disease in western Canadian cow-calf herds using an agent-based simulation model.

Johne's disease is an insidious infectious disease of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). Johne's disease can have important implications for animal welfare and risks causing economic losses in affected herds due to reduced productivity, premature culling and replacement, and veterinary costs. Despite the limited accuracy of diagnostic tools, testing and culling is the primary option for controlling Johne's disease in beef herds. However, evidence to inform specific test and cull strategies is lacking. In this study, a stochastic, continuous-time agent-based model was developed to investigate Johne's disease and potential control options in a typical western Canadian cow-calf herd. The objective of this study was to compare different testing and culling scenarios that included varying the testing method and frequency as well as the number and risk profile of animals targeted for testing using the model. The relative effectiveness of each testing scenario was determined by the simulated prevalence of cattle shedding MAP after a 10-year testing period. A second objective was to compare the direct testing costs of each scenario to identify least-cost options that are the most effective at reducing within-herd disease prevalence. Whole herd testing with individual PCR at frequencies of 6 or 12 months were the most effective options for reducing disease prevalence. Scenarios that were also effective at reducing prevalence but with the lowest total testing costs included testing the whole herd with individual PCR every 24 months and testing the whole herd with pooled PCR every 12 months. The most effective method with the lowest annual testing cost per unit of prevalence reduction was individual PCR on the whole herd every 24 months. Individual PCR testing only cows that had not already been tested 4 times also ranked well when considering both final estimated prevalence at 10 years and cost per unit of gain. A more in-depth economic analysis is needed to compare the cost of testing to the cost of disease, taking into account costs of culling, replacements and impacts on calf crops, and to determine if testing is an economically attractive option for commercial cow-calf operations.

Analysis of long non-coding RNA expression profile of bovine monocyte-macrophage infected by Mycobacterium avium subsp. paratuberculosis

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis. As a potential zoonotic pathogen, MAP also seriously threatens human health and social security. At present, long non-coding RNA (lncRNA) has attracted wide attention as an useful biomarker in various diseases. Therefore, our study analyzed the lncRNA expression profiles and lncRNA-mRNA regulatory network of MAP infected bovine monocytes-macrophages and uninfected bovine cells by high-throughput sequencing. A total of 4641 differentially expressed lncRNAs genes were identified, including 3111 up-regulated genes and 1530 down-regulated genes. In addition, lncRNA-mRNA interaction analysis was performed to predict the target genes of lncRNA. Among them, after MAP infection, 86 lncRNAs targeted to mRNA, of which only 6 genes were significantly different. The results of Gene Ontology (GO) enrichment analysis showed that the differentially expressed genes significantly enriched in functional groups were related to immune regulation. Multiple signal pathways including NF-κB, NOD-like receptor, Cytokine-cytokine receptor, Toll-like receptor signaling pathway, Chemokine signaling pathway, and other important biochemical, metabolic and signal transduction pathways were enriched in Kyoto Encyclopedia of Genes and Genomes (KEGG). In this study, analysis of macrophage transcriptomes in response to MAP infection is expected to provide key information to deeply understand role of the pathogen in initiating an inappropriate and persistent infection in susceptible hosts and molecular mechanisms that might underlie the early phases of paratuberculosis.

Correlates of vaccine protection against Mycobacterium avium sub-species paratuberculosis infection revealed in a transcriptomic study of responses in Gudair® vaccinated sheep.

A critical hindrance in the development of effective vaccine strategies to combat infectious disease is lack of knowledge about correlates of protection and of the host responses necessary for successful adaptive immunity. Often vaccine formulations are developed by stepwise experimentation, with incomplete investigation of the fundamental mechanisms of protection. Gudair® is a commercially available vaccine registered for use in sheep and goats for controlling spread of Mycobacterium avium sub-species paratuberculosis (MAP) infections and reduces mortality by up to 90%. Here, using an experimental infection model in sheep, we have utilized a transcriptomics approach to identify white blood cell gene expression changes in vaccinated, MAP-exposed Merino sheep with a protective response in comparison to those vaccinated animals that failed to develop immunity to MAP infection. This methodology facilitated an overview of gene-associated functional pathway adaptations using an in-silico analysis approach. We identified a group of genes that were activated in the vaccine-protected animals and confirmed stability of expression in samples obtained from naturally exposed commercially maintained sheep. We propose these genes as correlates of vaccine induced protection.

Immunoinformatics analysis of candidate proteins for controlling bovine paratuberculosis.

Paratuberculosis is debilitating chronic enteritis usually characterized by diarrhea, decreased milk production, and progressive cachexia. Mycobacterium avium subspecies paratuberculosis (MAP) causes significant economic losses by affecting dairy herds globally. Development of protective vaccines is considered as one of the most effective controlling measures for MAP infections. In the current study, hydrophilic parts of MAP2191 and FAP-P proteins as two vaccine candidates were analyzed using immunoinformatics approaches. After selecting the most hydrophilic parts of MAP2191 and FAP-P, helper and cytotoxic T-cell epitopes of ht-MAP2191 and ht-FAP-P were identified. The immunogenic, toxicity and physicochemical properties were assessed. Secondary structures of these proteins were predicted, and their tertiary structures were modeled, refined, and validated. Linear and conformational epitopes of corresponding B-cells were recognized. Then ht-MAP2191 and ht-FAP-P epitopes were employed for molecular docking simulations. The results indicated that ht-MAP2191 and ht-FAP-P were immunogenic, non-allergenic, and non-toxic and possess potent T-cell and B-cell epitopes. Eventually, these protein constructs were docked favorably against TLR4. According to the findings, ht-MAP2191 and ht-FAP-P could be effective protein-based vaccine candidates for paratuberculosis. It should be noted that to examine their efficacy, further in vitro and in vivo experiments are underway.

Are Reactive Oxygen Species (ROS) the Main Mechanism by Which Copper Ion Treatment Degrades the DNA of Mycobacterium avium subsp. paratuberculosis Suspended in Milk?

Mycobacterium avium subsp. paratuberculosis (MAP) is the causal agent of paratuberculosis. This pathogen is able to survive adverse environmental conditions, including the pasteurization process. Copper, a well-studied metal, is considered an important antibacterial tool, since it has been shown to inactivate even MAP in treated milk through unknown mechanisms. The aim of the present study is to show the effect of copper ions, and reactive oxygen species (ROS) generated in response to oxidative stress, on the damage to MAP DNA when exposed to a copper ion challenge in cow's milk. Spiked milk with different MAP bacterial loads was supplemented with blocking agents. These were either the copper chelators ethylenediaminetetraacetic acid (EDTA) and batocuproin (BCS) or the ROS quenchers D-mannitol, gallic acid and quercetin. The DNA protection, MAP viability and ROS production generated after exposure to a copper challenge were then measured. In a bacterial load of 104 cells mL-1, blocking effects by both the copper chelators and all the ROS quenchers offered significant protection to MAP DNA. In a concentration of 102 cells mL-1, only D-mannitol and a mix of quenchers significantly protected the viability of the bacteria, and only at a concentration of 106 cells mL-1 was there a lower production of ROS when supplementing milk with gallic acid, quercetin and the mix of quenchers. Based on these findings, it may be concluded that MAP DNA damage can be attributed to the combined effect of the direct copper ions and ROS generated. Nevertheless, taking into account the antioxidant environment that milk provides, the direct effect of copper could play a prominent role.

More insights about genomic population structure of Mycobacterium avium subspecies paratuberculosis (Map) from multiple hosts in west and central provinces of Iran using a boosted genotyping approach

To investigate the population genetic of Mycobacterium avium subsp. paratuberculosis (Map) in Iran, Mycobacterial Interspersed Repetitive Units (MIRUs) and Multi Locus Short Sequence Repeat (MLSSR) system were employed. Numerous genotypes by MIRU (N = 11) and MLSSR (N = 9) methods bearing discriminatory indices of 0.90 and 0.79 respectively, were obtained. Browsing the INRA–Nouzilly list (http://mac-inmv.tours.inra.fr/) detected 3 of the found patterns as new types. Some loci either MIRU-VNTR or SSR proved more polymorphic and therefore are recommended to be applied in priority for strain typing in the Iranian environment. While identical MIRU-VNTR or MLSSR patterns were detected among different conspecifics and geographical locations, dissimilar types were also observed at the same farms an indication of coexistence of Map strains within one herd. We suggest extension of the genotyping work described here to include more endogenous isolates in order to better analysis of transmission and virulence in epidemiology and control of paratuberculosis.

Exploration of Solanum xanthocarpum Schrad. & Wendl. against Mycobacterium avium Subspecies paratuberculosis and Assessment of Its Immunomodulatory and Anti-Inflammatory Potential.

Mycobacterium avium subspecies paratuberculosis (MAP), being a dairy-borne pathogen, resistant of pasteurization and other sterilization techniques, is a major cause for development of inflammatory bowel disorders such as Johne's disease (JD) in dairy animals and Crohn's Disease (CD) in humans, for which no therapy is available to date. In the absence of effective therapy or a vaccine, management of CD has been accomplished by removal of the affected intestines. However, usually, even after removal of 2/3 of the intestine, CD reoccurs. Hence, there exists a need to develop an alternative therapy for such infection. The potential of herbals remains unexplored against MAP and related infections. Therefore, the conducted study is a novel initiative for the evaluation of anti-mycobacterial activity of bioactive extracts of Solanum xanthocarpum Schrad. & Wendl. against MAP infection. The said plant was authenticated according to the Ayurvedic Pharmacopoeia of India. Qualitative and quantitative evaluation of the extracts were done using chromatographic and spectroscopic techniques. Preliminary in vitro pharmacological assessments revealed the immunomodulatory and anti-inflammatory potential of the extracts. REMA assay was conducted to determine their anti-MAP activity along with determination of the best active extract. The hydro-alcoholic extract showed the best inhibition of MAP, providing a potential ray of hope against this emerging major pathogen of animals, and associated with Crohn's disease and other autoimmune disorders in human beings.

A review of bovine colostrum preservation techniques.

Preservation of colostrum for neonatal dairy calves has seldom been seldom in recent years, much of the peer reviewed literature having been published in the 1970s and 1980s. First milking colostrum is high in bioactive immune enhancers such as immunoglobulins, lactoferrins, lysozymes and cytokines and is vital to confer passive immunity to newborn dairy calves to promote their health, welfare and future productivity. Bovine colostrum is advisedly restricted from the bulk milk supply for the first 8 milkings post calving due to high somatic cell counts and the risk of antimicrobial residues. As such, many producers refer to 'colostrum' as not only the first milking post calving, but also the aformentioned 'transition' milk. Colostrum is preserved in order to protect supply for feeding when production may be poor or where there is a glut of colostrum such as in seasonal calving systems. There are multiple reasons for newborn calves not to have access to their dam's colostrum, including multiple births, acute mastitis or maladapted maternal behaviour, especially in first lactation heifers. Shortages in colostrum may also be precipitated by purposeful discarding of colostrum from cows infected with Mycobacterium avium subsp paratuberculosis and Mycoplasma bovis. Broadly, colostrum may be preserved using low temperature (refrigeration or freezing) or chemical preservatives. The aim of this scoping review article was to identify options for preservation and gaps in research and to propose best practice for colostrum preservation.

The effect of risk-based trading and within-herd measures on Mycobacterium avium subspecies paratuberculosis spread within and between Irish dairy herds

Johne’s disease (bovine paratuberculosis) is an endemic disease caused by Mycobacterium avium subspecies paratuberculosis (Map). Map is transmitted between herds primarily through movement of infected but undetected animals. Within infected herds, possible control strategies include improving herd hygiene by reducing calf exposure to faeces from cows, reducing stress in cows resulting in a longer latently infected period where shedding is minimal, or culling highly test-positive cows soon after detection. Risk-based trading can be a strategy to reduce the risk that Map spreads between herds. Our objective was to assess whether within-herd measures combined with risk-based trading could effectively control Map spread within and between dairy cattle herds in Ireland. We used a stochastic individual-based and between-herd mechanistic epidemiological model to simulate Map transmission. Movement and herd demographic data were available from 1st January 2009–31st December 2018. In total, 13,353 herds, with 4,494,768 dairy female animals, and 72,991 bulls were included in our dataset. The movement dataset consisted of 2,304,149 animal movements. For each herd, a weekly indicator was calculated that reflected the probability that the herd was free from infection. The indicator value increased when a herd tested negative, decreased when animals were introduced into a herd, and became 0 when a herd tested positive. Based on this indicator value, four Johne’s assurance statuses were distinguished: A) ≥ 0.7 – 1.0, B) ≥ 0.3 – < 0.7, C) > 0.0 – < 0.3, and D) 0.0. A is the highest and D the lowest Johne’s assurance status. With risk-based trading some of the observed movements between herds were redirected based on Johne’s assurance status with the aim of reducing the risk that a non-infected herd acquired an infected animal. Risk-based trading effectively reduced the increase in herd prevalence over a 10-year-period in Ireland: from 50% without risk-based trading to 42% with risk-based trading in the metapopulation only, and 26% when external purchases were risk-based as well. However, for risk-based trading to be effective, a high percentage of dairy herds had to participate. The most important within-herd measures were improved herd hygiene and early culling of highly infectious cows. These measures reduced both herd and within-herd prevalence compared to the reference scenario. Combining risk-based trading with within-herd measures reduced within-herd prevalence even more effectively.