Unveiling genotypic diversity of Theileria orientalis in lethal outbreaks among bovines in Karnataka, India.

Theileria orientalis, the causal agent of oriental theileriosis, is known to cause mild disease in cattle and buffalo across the world. Recently, different genotypes of T. orientalis have emerged as pathogenic, causing high reported morbidity in cattle. This study focuses on investigating three suspected outbreaks of oriental theileriosis that resulted in fatalities among crossbred and indigenous bulls in Karnataka, India. Examination of blood smears revealed the presence of T. orientalis piroplasms within erythrocytes. The genetic characterization of T. orientalis was conducted by targeting specific markers, including the mpsp gene, p23 gene, and ribosomal DNA markers (18S rRNA gene, ITS-1, and ITS-2). Analysis based on the 18S rRNA gene unveiled the presence of both Type A and Type E genotypes of T. orientalis in the outbreaks. The mpsp gene-based analysis identified genotype 7 of T. orientalis in crossbred cows, whereas genotype 1 (Chitose B) was found to be present in indigenous bulls. Haplotype network analysis based on the mpsp gene revealed the presence of 39 distinct haplotypes within the 12 defined genotypes of T. orientalis with a high haplotype diversity of 0.9545 ± 0.017. Hematological and biochemical analysis revealed a decrease in calcium, hemoglobin levels, red blood cell counts, and phosphorus. This study constitutes the initial documentation of a clinical outbreak of oriental theileriosis in indigenous bulls with genotype 1 (Chitose 1B). Substantial epidemiological investigations are imperative to gain a comprehensive understanding of the geographical distribution of distinct genotypes and the diverse clinical manifestations of the disease across various hosts.

Bovine babesiosis in India: Estimation of prevalence by systematic review and meta analysis.

Bovine babesiosis is a serious threat to the livestock sector especially in tropical countries like India. Understanding the epidemiology of the disease in the country is essentially important in strategizing the available methods to effectively control the disease. Keeping this as the background, the present study was undertaken to estimate the pooled prevalence of bovine babesiosis in India. The relevant literature pertaining to bovine babesiosis was identified and a total of 49 studies published between 1983 and 2018 were included in the final systematic review and meta-analysis. Meta-analysis was conducted using meta-package of R software and prevalence estimates were calculated. Bovine babesiosis was reported from 21 states of India with pooled prevalence estimate of 6% (95% CI = 4%-9%) using random effect model. Zone wise analysis revealed highest pooled prevalence in the west zone and north zone (8%) followed by east zone (7%), central zone (6%), south zone (4%) and northeast zone (4%). The results of meta-analysis indicated high variability between studies. In addition, the pooled seroprevalence was high (29%) compared to prevalence of active infection (5%) of bovine babesiosis in India. Further, the pooled prevalence estimate of B. bigemina infection in India was more (7%) compared to B. bovis infection (1%). The estimation of prevalence of active infection and seroprevalence separately will helps to understand the actual disease prevalence in the country. The study indicated the wide prevalence of bovine babesiosis in India which urges for immediate mitigation strategies.

Mining the pervasiveness of surra in different animal species of Northeastern states of India: Assam, Mizoram and Tripura.

Trypanosoma evansi is a flagellated, extracellular haemoprotozoan parasite infecting a wide range of mammalian hosts including dromedaries, cattle, equines and dogs cause disease surra. Carrier animals with sub-clinical infection cause significant monetary losses to livestock holders and therefore detection of infection status using molecular diagnostic techniques becomes important in order to control the disease. In the current study cattle, buffalo, goat, pig and dog samples from three northeastern states of India-Assam, Mizoram and Tripura were screened to determine the prevalence of surra. A total of 1702 samples including 795 from Assam, 678 from Mizoram and 229 from Tripura were screened by CATT/T. evansi test out of which 16.8%, 27.1% and 22.3% samples in respective states were found to have antibodies against T. evansi. DNA detection of T. evansi by PCR amplification targeting VSG gene revealed the molecular prevalence of surra in Assam, Mizoram and Tripura as 8.5%, 7.5% and 4.4% respectively. The analysis of amplified partial VSG sequences showed 99% similarity within an animal species whereas 86-94% similarity was observed among different species of animals revealing the homogeneity. The study established the prevalence of surra in different species of animals in the three northeastern states of India-Assam, Mizoram and Tripura and this study is the first report of T. evansi infection in pig and goat from India. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12639-021-01392-z.

Seroprevalence of Trypanosoma evansi in cattle and analysis of associated climatic risk factors in Mizoram, India.

Surra, a haemoprotozoan parasitic disease even in subclinical form poses a challenge in terms of diagnosis and management to animal health practitioners and policy makers as well; eventually imparting financial loss to the livestock holders. A systematic study was designed to assess the seroprevalence of surra in cattle and associated climatic risk factors, by collecting 480 serum samples across the eight districts of Mizoram during 2017-2019. The apparent and true seroprevalence detected by card agglutination test was 37.08% (CI at 95%: 32.88-41.49) and 36.59% (CI at 95%: 32.4-40.99) whereas by recombinant Variable Surface Glycoprotein based indirect ELISA was 41.88% (CI at 95%: 37.5-46.3) and 40.35% (CI at 95%: 36.02-44.76) respectively. Climate parameters which influence vector population were extracted from their respective database and were correlated with seroprevalence data. Linear discriminant analysis revealed that air temperature, relative humidity and diurnal temperature range, leaf area index and soil moisture as significant risk factors discriminating seropositive and seronegative data sets classified by indirect ELISA. This study is the first report on seroprevalence of surra in cattle of Mizoram and the situation demands deployment of intervention strategies in order to assess the endemicity of the disease and thereby preventing the economic losses.

In-vitro evaluation of antimicrobial and insect repellent potential of supercritical-carbon dioxide (SCF-CO2) extracts of selected botanicals against stored product pests and foodborne pathogens.

In the present study, the antimicrobial and the insect repellent activity of 16 botanical extracts obtained by supercritical CO2 (SCF) extraction were evaluated. The present investigation was conducted as there is a necessity for exploration of natural botanical extracts that target both stored product insects and microbes. The antimicrobial activity was studied by disc diffusion and broth microdilution methods against ten microbial species, including Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis and Listeria monocytogenes), Gram-negative bacteria (Escherichia coli and Salmonella enterica), and fungi (Aspergillus flavus, Aspergillus paraciticus, Aspergillus ochraceous, Aspergillus niger and Penicillium verrucosum). Repellency assay was carried out by area preference method against three coleopteran insects (Tribolium castaneum, Rhyzopertha dominica and Sitophilus oryzae). Among all the extracts, thyme and ajwain were effective against all the tested bacteria with a minimum inhibition concentration (MIC) of 256-1024 µg/mL. Hop extract resulted in better antibacterial activity against all the tested Gram-positive bacteria with a MIC of 32-64 µg/mL. Oregano, thyme and ajwain extracts showed broad-spectrum antifungal activity against all the tested fungi with MIC of 128-1024 µg/mL. Most of the extracts exhibited class V (80.1-100%) repellency against T. castaneum. Extracts of hop, ajwain and thyme were found to have strong repellency against T. castaneum and R. dominica. Therefore, SCF extracts of ajwain and thyme can be explored further for the application of bio-extracts as a growth limiting factors in a microcosm where such consortia thrive.

Potential of pyrethroid-synergised pyrethrum on stored product insects and implications for use as prophylactic sprays.

The study was conducted to evaluate the synergistic effects of 2% pyrethrum extract with synthetic pyrethroids on the mortality of stored product insects. Contact toxicity was performed at variable concentrations observing mortality at 12, 24 and 48 h durations. The results of the present study indicated that, pyrethrum + deltamethrin combination (25:1 ratio) was effective on the adults of Rhyzopertha dominica (F.) and Tribolium castaneum (Herbst). On the other hand, pyrethrum + cypermethrin combination proved effective against Sitophilus oryzae (L.). The efficacy of the tested combination showed reasonable increase in mortality response in treated insects over increasing exposures. At 48 h, 450 ppm pyrethrum + deltamethrin combination induced 25, 90 and 97% mortalities in S. oryzae, T. castaneum and R. dominica adults; while, pyrethrum-cypermethrin combination recorded 75, 45 and 75% mortalities respectively. On the other hand, it was observed that, among the pyrethrum alone treatments i.e. at 300, 450 and 600 ppm concentrations, maximum mortality (62.5%) was observed in S. oryzae exposed to 600 ppm pyrethrum for 48 h. The effective LC50 concentrations for pyrethrum (600 ppm) + deltamethrin combination was estimated to be as 0.1987 and 0.7039 µl/cm2 for R. dominica and T. castaneum adults respectively. Contrastingly, for treatments with S. oryzae, a LC50 value of 0.8673 µl/cm2 was recorded for pyrethrum (600 ppm) + cypermethrin mixture. This investigation strengthens the fact that pyrethrum along with pyrethroids is effective against storage insect pests which can be promisingly a safer insecticidal combination.