Zika virus – emergence,evolution, pathology,diagnosis, and control: current global scenario and future perspectives – a comprehensive review

This review converses the Zika virus which has attained global concern due to its rapid pandemic potential and impact on humans. Though Zika virus was first isolated in 1947, till the recent large-scale outbreak which occurred in Micronesia, in 2007, the virus was placed into the innocuous pathogen category. The World Health Organization on 1 February 2016 declared it as a ‘Public Health Emergency of International Concern.’ Of the note, American as well as Pacific Island strains/isolates is relatively closer to Asian lineage strains. The African and American strains share more than 87.5% and 95% homologies with Asian strains/isolates, respectively. Asian strains form independent clusters, except those isolated from China, suggesting relatively more diversity than African strains. Prevention and control are mainly aimed at the vector population (mosquitoes) with Aedes aegypti being the main species. Surveys in Africa and Asia indicated seropositivity in various animal species. However, so far its natural reservoir is unknown. There is an urgent need to understand why Zika virus has shifted from being a virus that caused mild illness to unforeseen birth defects as well as autoimmune-neurological problems. Unfortunately, an effective vaccine is not available yet. Availability of cryo-electron microscopy based on 3.8 Å resolution revealing mature Zika virus structure and the probable virus attachment site to host cell would provide critical insights into the development of antiviral treatments and vaccines.     

Antigenic and genetic variations in European and North American equine influenza virus strains (H3N8) isolated from 2006 to 2007

Equine influenza virus (EIV) surveillance is important in the management of equine influenza. It provides data on circulating and newly emerging strains for vaccine strain selection. To this end, antigenic characterisation by haemaggluttination inhibition (HI) assay and phylogenetic analysis was carried out on 28 EIV strains isolated in North America and Europe during 2006 and 2007. In the UK, 20 viruses were isolated from 28 nasopharyngeal swabs that tested positive by enzyme-linked immunosorbent assay. All except two of the UK viruses were characterised as members of the Florida sublineage with similarity to A/eq/Newmarket/5/03 (clade 2). One isolate, A/eq/Cheshire/1/06, was characterised as an American lineage strain similar to viruses isolated up to 10 years earlier. A second isolate, A/eq/Lincolnshire/1/07 was characterised as a member of the Florida sublineage (clade 1) with similarity to A/eq/Wisconsin/03. Furthermore, A/eq/Lincolnshire/1/06 was a member of the Florida sublineage (clade 2) by haemagglutinin (HA) gene sequence, but appeared to be a member of the Eurasian lineage by the non-structural gene (NS) sequence suggesting that reassortment had occurred. A/eq/Switzerland/P112/07 was characterised as a member of the Eurasian lineage, the first time since 2005 that isolation of a virus from this lineage has been reported. Seven viruses from North America were classified as members of the Florida sublineage (clade 1), similar to A/eq/Wisconsin/03. In conclusion, a variety of antigenically distinct EIVs continue to circulate worldwide. Florida sublineage clade 1 viruses appear to predominate in North America, clade 2 viruses in Europe.     

Seroprevalences of antibodies against bovine leukemia virus, bovine viral diarrhea virus, Mycobacterium avium subspecies paratuberculosis, and Neospora caninum in beef and dairy cattle in Manitoba

Of 1204 dairy cows and 1425 beef cows sampled, 60.8% and 10.3% were seropositive for Bovine leukemia virus, 4.5% and 1.7% were seropositive for Mycobacterium avium subspecies paratuberculosis, and 8.3% and 9.1% were seropositive for Neospora caninum, respectively, while 28.1% of dairy herds had unvaccinated animals with titres > or = 1:64 for Bovine viral diarrhea virus.     

Cellular Immune Responses to 35 kDa Recombinant Antigen of Mycobacterium avium paratuberculosis

Mycobacterium avium paratuberculosis is the causative agent of Johne disease, a chronic ulcerative intestinal condition in ruminant animals. Owing to the predominance of cellular response in subclinical forms of the infection, identification of M. a. paratuberculosis antigens eliciting host cell-mediated immune (CMI) reaction is crucial for early control of the disease. A 35 kDa protein of M. a. paratuberculosis was studied for its ability to elicit CMI responses using a mouse model. Lymphoproliferation and IFN-γ response were used to measure the CMI response. Recombinant 35 kDa protein (P35) stimulated proliferation of mouse mononuclear splenocytes sensitized with M. a. paratuberculosis. The P35 elicited increased nitrite production from mononuclear splenocytes from M. a. paratuberculosis-sensitized mice. In addition, RT-PCR-based semiquantitative IFN-γ measurement showed that stimulation with P35 is associated with significant expression of IFN-γ mRNA in M. a. paratuberculosis-sensitized mouse splenocytes. The results indicate that the 35 kDa protein of M. a. paratuberculosis is associated with CMI response in the host.     

The studies on nutrient balances in crossbred cattle bulls fed chopped green sugarcane tops supplemented with some agro industrial by- products

Fifteen adult crossbred cattle bulls, 18-22 months old (mean body weight 286.33 + 9.43) were divided into 3 groups following RBD design and were fed sugarcane tops (SCT) supplemented with some agro-industrial byproducts and concentrate feeds to determine nitrogen, Ca and P in crossbred cattle bull. For this purpose, crossbred cattle bulls were fed for 30 days ad lib SCT supplemented with Wheat bran (WB), Lentil chuni (LC) and WB + LC (50:50) in Group I, II, and III respectively. The balance values were 15.28 + 2.70, 26.85 + 4.35 and 18.00 + 3.17 for nitrogen, 11.77 + 1.34, 12.94 + 2.96 and 15.38 + 1.15 for calcium, 11.74 + 0.64, 11.26 + 1.58 and 11.69 + 0.79 for phosphorus in group I, II and III, respectively. There were no significant differences among the experimental groups in Ca and P balance values but balance of nitrogen was significantly (P < 0.05) higher in group II as compared to group I and III. It may indicated that the rumen fermentation was more appropriate in group III where animals were fed 50% lentil chuni and 50% wheat bran (supplementation of both protein and energy).     

Advances in therapeutic and managemental approaches of bovine mastitis: a comprehensive review

Mastitis (intramammary inflammation) caused by infectious pathogens is still considered a devastating condition of dairy animals affecting animal welfare as well as economically incurring huge losses to the dairy industry by means of decreased production performance and increased culling rates. Bovine mastitis is the inflammation of the mammary glands/udder of bovines, caused by bacterial pathogens, in most cases. Routine diagnosis is based on clinical and subclinical forms of the disease. This underlines the significance of early and rapid identification/detection of etiological agents at the farm level, for which several diagnostic techniques have been developed. Therapeutic regimens such as antibiotics, immunotherapy, bacteriocins, bacteriophages, antimicrobial peptides, probiotics, stem cell therapy, native secretory factors, nutritional, dry cow and lactation therapy, genetic selection, herbs, and nanoparticle technology-based therapy have been evaluated for their efficacy in the treatment of mastitis. Even though several strategies have been developed over the years for the purpose of managing both clinical and subclinical forms of mastitis, all of them lacked the efficacy to eliminate the associated etiological agent when used as a monotherapy. Further, research has to be directed towards the development of new therapeutic agents/techniques that can both replace conventional techniques and also solve the problem of emerging antibiotic resistance. The objective of the present review is to describe the etiological agents, pathogenesis, and diagnosis in brief along with an extensive discussion on the advances in the treatment and management of mastitis, which would help safeguard the health of dairy animals.     

Importance of brucellosis control programs of livestock on the improvement of one health

Brucellosis not only represents an important health restraint on livestock but also causes high economic losses in many developing countries worldwide. Despite considerable efforts made for the control of brucellosis, the disease is still spreading in many regions (such as the Middle East) where it represents one of the most important health hazards impacting both animals and humans. The present review aims to investigate the efficacy of veterinary control programs regarding brucellosis, with a special focus on current prevention, control, and eradication approaches. The reasons for unsuccessful control programs such as the absence of highly effective vaccines and non-certified bulls are also debated, to understand why the prevalence of brucellosis in livestock is not decreasing in many areas despite considerable efforts taken to date. The importance of governmental and regional investment in brucellosis control remains one of the main limiting factors owing to the limited budget allocated to tackle this disease. In this context, one health concept has generated novel comprehensive approaches with multiple economic implications across the livestock industry and public health. However, the implementation of such global preventive strategies appears to be a key issue for many endemic and low-income countries. According to the collected data, epidemiological contexts including management and trade systems along with well-defined agro-ecological zones should be evaluated in brucellosis endemic countries to improve milk production and to enhance the sustainability of the livestock sector at both national and regional levels.     

A family of IFN-γ-inducible 65-kD GTPases protects against bacterial infection

Immune interferon gamma (IFN-γ) is essential for mammalian host defense against intracellular pathogens. IFN-γ induces nearly 2000 host genes, yet few have any assigned function. Here, we examined a complete mouse 65-kilodalton (kD) guanylate-binding protein (Gbp) gene family as part of a 43-member IFN-γ-inducible guanosine triphosphatase (GTPase) superfamily in mouse and human genomes. Family-wide loss-of-function analysis found that at least four Gbps--Gbp1, Gbp6, Gbp7, and Gbp10--conferred cell-autonomous immunity to listerial or mycobacterial infection within macrophages and gene-deficient animals. These Gbps solicited host defense proteins, including the phagocyte oxidase, antimicrobial peptides, and autophagy effectors, to kill intracellular bacteria. Thus, specific 65-kD Gbps coordinate a potent oxidative and vesicular trafficking program to protect the host from infection.     

Stoloniferous shoot protoplast,an efficient cell system in potato for somatic cell genetic manipulations

The present study reports that protoplasts isolated from stoloniferous shoots (SS) of potato represent an efficient system for somatic cell genetic manipulations. SS were established from single-node cuttings on MS medium supplemented with either 0.1 or 0.2 M sucrose (Suc), and protoplasts were isolated and cultured within the alginate strip, following an improved method. SS induced by 0.1 M Suc yielded 8–22 × 10⁵ protoplasts g⁻¹ fresh mass, with a high morphogenic competence. However, 0.2 M Suc-induced SS yielded protoplasts that contained large amounts of starch grains, resulting in their high degree of fragility, delayed cell division and poor morphogenic competence. For symmetric somatic hybridization (electrofusion) between Solanum tuberosum Gp. Tuberosum androgenic (di)haploid (2n = 2x = 24) ‘C-13’ and diploid (2n = 2x = 24) wild species S. pinnatisectum, protoplasts isolated from 0.1 M Suc-induced SS were also found to be most responsive. Out of several putative somatic hybrids, there were two tetraploids and five diploids, with 48 and 24 chromosomes, respectively at all the three shoot layers (L₁–L₃). This precluded the occurrence of mixoploidy vis-à-vis chimaerism in regenerants, as common in somatic fusion involving mesophyll protoplasts of S. pinnatisectum. Nuclear microsatellite analyses based on the two single-locus nSSR loci (STM0037 and STM2030) confirmed that one of the tetraploids was a true nuclear hybrid (heterokaryon), while the other a homokaryon of the Tuberosum parent ‘C-13’. The use of 0.2 M Suc-induced SS protoplasts for fundamental studies on tissue- and/or cell type-specific transient gene expression underlying tuberization has been discussed.