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Malaria poses a significant threat to global health, with particular severity in Nigeria. Understanding key factors influencing health outcomes is crucial for addressing health disparities. Disease mapping plays a vital role in assessing the geographical distribution of diseases and has been instrumental in epidemiological research. By delving into the spatiotemporal dynamics of malaria trends, valuable insights can be gained into population dynamics, leading to more informed spatial management decisions. This study focused on examining the evolution of malaria in Nigeria over twenty years (2000-2020) and exploring the impact of environmental factors on this variation. A 5-year-period raster map was developed using malaria indicator survey data for Nigeria's six geopolitical zones. Various spatial analysis techniques, such as point density, spatial autocorrelation, and hotspot analysis, were employed to analyze spatial patterns. Additionally, statistical methods, including Principal Component Analysis, Spearman correlation, and Ordinary Least Squares (OLS) regression, were used to investigate relationships between indicators and develop a predictive model. The study revealed regional variations in malaria prevalence over time, with the highest number of cases concentrated in northern Nigeria. The raster map illustrated a shift in the distribution of malaria cases over the five years. Environmental factors such as the Enhanced Vegetation Index, annual land surface temperature, and precipitation exhibited a strong positive association with malaria cases in the OLS model. Conversely, insecticide-treated bed net coverage and mean temperature negatively correlated with malaria cases in the same model. The findings from this research provide valuable insights into the spatiotemporal patterns of malaria in Nigeria and highlight the significant role of environmental drivers in influencing disease transmission. This scientific knowledge can inform policymakers and aid in developing targeted interventions to combat malaria effectively.
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Sistemas de Informação Geográfica , Malária , Análise Espaço-Temporal , Nigéria/epidemiologia , Malária/epidemiologia , Malária/transmissão , Humanos , PrevalênciaRESUMO
South Africa's efforts toward eliminating malaria have positioned the country in the pre-elimination stage. Imported and sub-microscopic cases still contribute to the persistence of malaria in regions of low transmission as identified in this study where diagnostics is built largely on the use of Rapid Diagnostic Test (RDT). However, the presence of Pfhrp2/3 gene deletion is known to interfere with the accuracy of diagnosis with the use of RDT. Malaria elimination and detection of Pfhrp2/3 gene deletion in the pre-elimination setting requires accurate molecular surveillance. With the core objective of this study being the determination of the presence sub-microscopic malaria cases and deleted Pfhrp2/3 gene markers, a total of 354 samples were collected from five districts of KwaZulu Natal, South Africa. These samples were prepared for molecular analysis using primers and PCR conditions specific for amplification of 18S rRNA and msp-1gene. Positive amplicons were analysed for the presence of Pfhrp2/3 and flanking genes, along with Sanger sequencing and phylogenetic studies. Out of 354 samples collected 339 were tested negative with PfHRP2 based RDTs. Of these Pfhrp2 and Pfhrp3 gene deletions were confirmed in 94.7% (18/19) and 100% (19/19) respectively. High migration rate (75%) among the study participants was noted and phylogenetic analysis of sequenced isolates showed close evolutionary relatedness with India, United Kingdom, Iran, and Myanmar and China isolates. Molecular-based test is recommended as an essential surveillance tool for malaria management programs as the target focuses on elimination.
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Antígenos de Protozoários , Deleção de Genes , Malária Falciparum , Plasmodium falciparum , Proteínas de Protozoários , Proteínas de Protozoários/genética , África do Sul/epidemiologia , Humanos , Plasmodium falciparum/genética , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Falciparum/diagnóstico , Malária Falciparum/genética , Malária Falciparum/prevenção & controle , Antígenos de Protozoários/genética , FilogeniaRESUMO
The One Health (OH) approach is used to control/prevent zoonotic events. However, there is a lack of tools for systematically assessing OH practices. Here, we applied the Global OH Index (GOHI) to evaluate the global OH performance for zoonoses (GOHI-Zoonoses). The fuzzy analytic hierarchy process algorithm and fuzzy comparison matrix were used to calculate the weights and scores of five key indicators, 16 subindicators, and 31 datasets for 160 countries and territories worldwide. The distribution of GOHI-Zoonoses scores varies significantly across countries and regions, reflecting the strengths and weaknesses in controlling or responding to zoonotic threats. Correlation analyses revealed that the GOHI-Zoonoses score was associated with economic, sociodemographic, environmental, climatic, and zoological factors. Additionally, the Human Development Index had a positive effect on the score. This study provides an evidence-based reference and guidance for global, regional, and country-level efforts to optimize the health of people, animals, and the environment.
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BACKGROUND: Understanding the genetic structure of P. falciparum population in different regions is pivotal to malaria elimination. Genetic diversity and the multiplicity of infection are indicators used for measuring malaria endemicity across different transmission settings. Therefore, this study characterized P. falciparum infections from selected areas constituting pre-elimination and high transmission settings in South Africa and Nigeria, respectively. METHODS: Parasite genomic DNA was extracted from 129 participants with uncomplicated P. falciparum infections. Isolates were collected from 78 participants in South Africa (southern Africa) and 51 in Nigeria (western Africa). Allelic typing of the msp1 and msp2 genes was carried out using nested PCR. RESULTS: In msp1, the K1 allele (39.7%) was the most common allele among the South African isolates, while the RO33 allele (90.2%) was the most common allele among the Nigerian isolates. In the msp2 gene, FC27 and IC3D7 showed almost the same percentage distribution (44.9% and 43.6%) in the South African isolates, whereas FC27 had the highest percentage distribution (60.8%) in the Nigerian isolates. The msp2 gene showed highly distinctive genotypes, indicating high genetic diversity in the South African isolates, whereas msp1 showed high genetic diversity in the Nigerian isolates. The RO33 allelic family displayed an inverse relationship with participants' age in the Nigerian isolates. The overall multiplicity of infection (MOI) was significantly higher in Nigeria (2.87) than in South Africa (2.44) (p < 0.000 *). In addition, heterozygosity was moderately higher in South Africa (1.46) than in Nigeria (1.13). CONCLUSIONS: The high genetic diversity and MOI in P. falciparum that were observed in this study could provide surveillance data, on the basis of which appropriate control strategies should be adopted.
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The progression of genetic selection techniques to enhance farm animal performance traits is guided by the present level of genetic variation and maternal impact in each trait, as well as the genetic association between traits. This study was conducted on a population of Mecheri sheep maintained from 1980 to 2018 at Mecheri Sheep Research Station, Pottaneri, India, to determine variance and covariance components, as well as genetic parameters for various production performance traits. A total of 2616 lambs, produced by 1044 dams and 226 sires, were examined in the study and the production traits of Mecheri sheep assessed include birth weight (BW), weaning weight (WW), six-month weight (SMW), nine-month weight (NMW), and yearling weight (YW). The Bayesian approach, using the Gibbs sampler, analyzed six animal models with different combinations of additive direct and maternal additive effects. Direct genetics, maternal genetics, and residual effects models were the major contributors to total phenotypic variation for all the production traits studied. Direct heritability estimates of birth weight, WW, SMW, NMW, and YW were 0.25, 0.20, 0.12, 0.14, and 0.13, respectively. The maternal heritability estimated for BW, WW, SMW, NMW, and YW were 0.17, 0.10, 0.12, 0.14, and 0.14, respectively. The maternal effects had a major impact on the pre-weaning production traits. The genetic correlations estimated between different pairs of production traits studied ranged from 0.19 to 0.93. The body weight at birth exhibited a higher genetic relationship with weaning weight than post-weaning growth characteristics, and the genetic correlation between weaning weight and post-weaning attributes was moderate to high (0.52 to 0.72). Based on the additive genetic variance in weaning weight and the correlation estimates of weaning weight with post-weaning traits, weaning weight was proposed as a selection criterion for improving growth traits in Mecheri sheep.
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Animais Domésticos , Ovinos/genética , Animais , Teorema de Bayes , Peso ao Nascer/genética , Fenótipo , Modelos Animais , Peso Corporal/genéticaRESUMO
Buruli ulcer (BU) is a neglected tropical disease. It is caused by the bacterium Mycobacterium ulcerans and is characterized by skin lesions. Several studies were performed testing the Bacillus Calmette-Guérin (BCG) vaccine in human and animal models and M. ulcerans-specific vaccines in animal models. However, there are currently no clinically accepted vaccines to prevent M. ulcerans infection. The aim of this study was to identify T-cell and B-cell epitopes from the mycobacterial membrane protein large (MmpL) proteins of M. ulcerans. These epitopes were analysed for properties including antigenicity, immunogenicity, non-allergenicity, non-toxicity, population coverage and the potential to induce cytokines. The final 8 CD8+, 12 CD4+ T-cell and 5 B-cell epitopes were antigenic, non-allergenic and non-toxic. The estimated global population coverage of the CD8+ and CD4+ epitopes was 97.71%. These epitopes were used to construct five multi-epitope vaccine constructs with different adjuvants and linker combinations. The constructs underwent further structural analyses and refinement. The constructs were then docked with Toll-like receptors. Three of the successfully docked complexes were structurally analysed. Two of the docked complexes successfully underwent molecular dynamics simulations (MDS) and post-MDS analysis. The complexes generated were found to be stable. However, experimental validation of the complexes is required.
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Úlcera de Buruli , Mycobacterium ulcerans , Vacinas , Humanos , Animais , Mycobacterium ulcerans/química , Proteínas de Membrana , Epitopos de Linfócito B/química , Úlcera de Buruli/prevenção & controle , Epitopos de Linfócito T , Simulação de Acoplamento MolecularRESUMO
Limosilactobacillus reuteri ZJ625 and Ligilactobacillus salivarius ZJ614 are potential probiotic bacteria with improved benefits when administered to the host as a multi-strain preparation. To elucidate the mechanisms of cell-to-cell crosstalk between these two strains, we studied their intracellular and extracellular proteomes in co-culture by liquid-chromatography mass-spectrometry (LC-MS) using Dionex Nano-RSLC and fusion mass spectrometer. The experiment consisted of five biological replicates, and samples were collected during the mid-exponential growth phase. The quantitative proteomic profiles revealed several differentially expressed proteins (DEPs), which are down- or up-regulated between and within groups for both the intracellular and extracellular proteomes. These DEPs include proteins synthesising autoinducer-2, a sensor compound for cell-to-cell bacterial crosstalk during quorum sensing in mixed culture. Other important DEPs identified include enolase, phosphoglycerate kinase, and l-lactate dehydrogenase, which play roles in carbohydrate metabolism. Proteins associated with transcription, ATP production and transport across the membrane, DNA repair, and those with the potential to bind to the host epithelium were also identified. The post-translational modifications associated with the proteins include oxidation, deamidation, and ammonia loss. Importantly, this study revealed a significant expression of S-ribosylhomocysteine lyase (luxS) involved in synthesising autoinducer-2 that plays important roles in quorum sensing, aiding bacterial cell-to-cell crosstalk in co-cultures. The proteome of L. salivarius ZJ614 was most affected when co-cultured with L. reuteri ZJ625. In contrast, omitting some medium components from the defined medium exerted more effects on L. reuteri ZJ625 than L. salivarius ZJ614.
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Toxoplasmosis is a zoonotic disease caused by the protozoan parasite, Toxoplasma gondii known to infect almost all animals, including birds and humans globally. This disease has impacted the livestock industry and public health, where infection of domestic animals increases the zoonotic risk of transmission of infection to humans, threatening public health. Hence the need to discover novel and safe vaccines to fight against toxoplasmosis. In the current study, a novel multiepitope vaccine was designed using immunoinformatics techniques targeting T. gondii AMA1, GRA7 and ROP16 antigens, consisting of antigenic, immunogenic, non-allergenic and cytokine inducing T-cell (9 CD8+ and 15 CD4+) epitopes and four (4) B-cell epitopes fused together using AAY, KK and GPGPG linkers. The tertiary model of the proposed vaccine was predicted and validated to confirm the structural quality of the vaccine. The designed vaccine was highly antigenic (antigenicity = 0.6645), immunogenic (score = 2.89998), with molecular weight of 73.35 kDa, instability and aliphatic index of 28.70 and 64.10, respectively; and GRAVY of -0.363. The binding interaction, stability and flexibility were assessed with molecular docking and dynamics simulation, which revealed the proposed vaccine to have good structural interaction (binding affinity = -106.882 kcal/mol) and stability when docked with Toll like receptor-4 (TLR4). The results revealed that the Profilin-adjuvanted vaccine is promising, as it predicted induction of enhanced immune responses through the production of cytokines and antibodies critical in blocking host invasion.
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Babesia infection is a tick-borne protozoan disease associated with significant veterinary, economic, and medical importance. This infection affects many hosts, ranging from wild to domestic animals and including man. All vertebrates serve as potential carriers due to the huge diversity of the species. Babesiosis has been associated with severe economic loss in livestock production, especially in cattle farming, and is also a major public health concern in man, which could be fatal. The infection is usually opportunistic, ranging from asymptomatic to symptomatic, usually in immunocompromised subjects or under conditions of stressful management. This study was designed to uncover trends in relation to publication growth and further explore research output regarding babesiosis from data indexed in the WoS. The WoS is the only platform used to map publications on Babesia infection. The search term "babesiosis" or "Babesia infection" was used to extract articles published across the study period from 1982 to 2022. The inclusion criteria were restricted to only articles for the analysis. The results from the search query showed that a total of 3763 articles were published during the study period with an average of 91.70 ± 43.87 articles annually and an average total citation (n = 1874.8). An annual growth rate of 2.5% was recorded during the study period. The year 2021 had the highest number of published articles (n = 193, 5.1%) and citations (n = 7039). The analysis of the most relevant keywords and titles showed that infection (n = 606, 16.1%), babesiosis (n = 444, 11.7%), and Babesia (n = 1302, 16%) were the most relevant keyword plus (ID), author keyword (DE), and title, respectively. The common conceptual framework analysis through K-means clustering showed two clusters comprising 4 and 41 elements, respectively. The United States of America is the top-performing country in terms of article production (n = 707, 20.8%) and the leading funder for babesiosis research, with two of its agencies ranked at the top. These are the Department of Health and Human Services (n = 254, 6.7%) and the National Institute of Health (n= 238,6.3%). Igarashi I. is the top-performing author (n = 231, 6.1%), while Veterinary Parasitology is ranked the top journal (n = 393, 10.4%) in terms of babesiosis publications. Overall, an increase in publications was observed in the study period, with significant output from developed nations.
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Babesia , Babesiose , Doenças Transmitidas por Carrapatos , Humanos , Animais , Bovinos , Estados Unidos , Babesiose/epidemiologia , Bibliometria , Animais DomésticosRESUMO
Despite various efforts and policy implementation aimed at controlling and eliminating malaria, imported malaria remains a major factor posing challenges in places that have made progress in malaria elimination. The persistence of malaria in Limpopo Province has largely been attributed to imported cases, thus reducing the pace of achieving the malaria-free target by 2025. Data from the Limpopo Malaria Surveillance Database System (2010-2020) was analyzed, and a seasonal auto-regressive integrated moving average (SARIMA) model was developed to forecast malaria incidence based on the incidence data's temporal autocorrelation. The study found that out of 57,288 people that were tested, 51,819 (90.5%) cases were local while 5469 (9.5%) cases were imported. Mozambique (44.9%), Zimbabwe (35.7%), and Ethiopia (8.5%) were the highest contributors of imported cases. The month of January recorded the highest incidence of cases while the least was in August. Analysis of the yearly figures showed an increasing trend and seasonal variation of recorded malaria cases. The SARIMA (3,1,1) X (3,1,0) [12] model used in predicting expected malaria case incidences for three consecutive years showed a decline in malaria incidences. The study demonstrated that imported malaria accounted for 9.5% of all cases. There is a need to re-focus on health education campaigns on malaria prevention methods and strengthening of indoor residual spray programs. Bodies collaborating toward malaria elimination in the Southern Africa region need to ensure a practical delivery of the objectives.
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Malária , Humanos , Malária/epidemiologia , Malária/prevenção & controle , África Austral , Estações do Ano , Incidência , Etiópia/epidemiologia , ViagemRESUMO
The concept of probiotics is witnessing increasing attention due to its benefits in influencing the host microbiome and the modulation of host immunity through the strengthening of the gut barrier and stimulation of antibodies. These benefits, combined with the need for improved nutraceuticals, have resulted in the extensive characterization of probiotics leading to an outburst of data generated using several 'omics' technologies. The recent development in system biology approaches to microbial science is paving the way for integrating data generated from different omics techniques for understanding the flow of molecular information from one 'omics' level to the other with clear information on regulatory features and phenotypes. The limitations and tendencies of a 'single omics' application to ignore the influence of other molecular processes justify the need for 'multi-omics' application in probiotics selections and understanding its action on the host. Different omics techniques, including genomics, transcriptomics, proteomics, metabolomics and lipidomics, used for studying probiotics and their influence on the host and the microbiome are discussed in this review. Furthermore, the rationale for 'multi-omics' and multi-omics data integration platforms supporting probiotics and microbiome analyses was also elucidated. This review showed that multi-omics application is useful in selecting probiotics and understanding their functions on the host microbiome. Hence, recommend a multi-omics approach for holistically understanding probiotics and the microbiome.
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Y-chromosome short tandem repeats (Y-STRs) are essential in understanding genetic structure and diversity of human populations and, most importantly, in identification of male perpetrators in criminal investigations. DNA methylation differences have been reported in human populations and methylation pattern at the CpG sites found within or flanking the Y-STR sites could also aid in human identification. Studies based on DNA methylation (DNAm) at Y-STRs are currently limited. The current study aimed to analyze the Y-STR diversity in South African Black and Indian individuals living in KwaZulu-Natal, Durban, South Africa, with the Yfiler™ Plus Kit and to analyze DNAm patterns in Y-STR markers CpG sites. DNA from 247 stored saliva samples were isolated and quantified. Across the 27 Y-STR loci in the Yfiler™ Plus Kit, 253 alleles were observed in 113 South African Black and Indian males, 112 unique haplotypes were observed, and one haplotype appeared twice (two Black individuals). No statistically significant differences were observed in the genetic diversity between the two population groups (Fst = 0.028, p-value ≥ 0.05). The kit showed a high discrimination capacity (DC) of 0.9912 and an overall haplotype diversity (HD) = 0.9995 among the sampled population groups. DYS438 and DYS448 markers displayed 2 and 3 CpG sites, respectively. Based on the two-tailed Fisher's Exact test, there were no statistically significant differences in the DNAm levels at DYS438 CpGs of Black and Indian males (p > 0.05). The Yfiler™ Plus Kit can be considered highly discriminatory among South African Black and Indian males. Studies on the South African population using Yfiler™ Plus Kit are scarce. Hence, accumulating Y-STR data on the diverse South African population will enhance the representation of South Africa in STR databases. Knowing which Y-STR markers are significantly informative for South Africa is essential for developing Y-STR kits better suited for the different ethnic groups. And to the best of our knowledge, DNA methylation analysis in Y-STR for different ethnic groups has never been done before. Complementing Y-STR data with methylation knowledge could provide population-specific information for forensic identification.
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Metilação de DNA , Genética Populacional , Humanos , Masculino , África do Sul , Cromossomos Humanos Y , Impressões Digitais de DNA , Reação em Cadeia da Polimerase , Repetições de Microssatélites , HaplótiposRESUMO
The phenolic structural analogues of synthetic antioxidants such as butylated hydroxytoluene (BHT) in essential oils have been reported to exhibit antioxidant properties. Additionally, their lipophilicity makes them suitable for use in lipid-rich foods. This study evaluated the antioxidant capacity of carvacrol, a monoterpenoid antioxidant compound in the Monodora myristica (Gaertn.) seed essential oil, compared to the seed essential oil and BHT. In vitro studies (ferric reducing antioxidant power (FRAP), metal chelating activity (MCA), and nitric oxide scavenging activity (NOSA)) were conducted to ascertain if the antioxidant capacity of carvacrol was comparable to that of the seed essential oil. The potential binding affinity and molecular interactions between carvacrol and lipoxygenase (LOX) and its homologous model were investigated in silico. The molecular docking was performed using Autodock Vina, and the best poses were subjected to molecular dynamics simulation. The IC50 for MCA and NOSA were: carvacrol 50.29 µL/mL, seed essential oil (SEO) 71.06 µL/mL; and carvacrol 127.61 µL/mL, SEO 165.18 µL/mL, respectively. The LOX model was Ramachandran favoured (97.75%) and the overall quality factor in the ERRAT plot was 95.392. The results of the molecular docking and molecular dynamics simulations revealed that lipoxygenase has a higher affinity (-22.79 kcal/mol) for carvacrol compared to BHT. In the LOX-BHT and LOX-carvacrol complexes, the root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), and the radius of gyration (RoG) were not significantly different, indicating similar molecular interactions. The results obtained from this study suggest that carvacrol exhibits an antioxidant capacity that may be explored as an alternative for crude essential oils and synthetic compounds during the storage of lipid-rich foods.
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Antioxidantes , Óleos Voláteis , Antioxidantes/química , Armazenamento de Alimentos/métodos , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Simulação de Acoplamento Molecular , Estudos Prospectivos , Quelantes , LipoxigenasesRESUMO
Many factors, such as the resistance to pesticides and a lack of knowledge of the morphology and molecular structure of malaria vectors, have made it more challenging to eradicate malaria in numerous malaria-endemic areas of the globe. The primary goal of this review is to discuss malaria vector control methods and the significance of identifying species in vector control initiatives. This was accomplished by reviewing methods of molecular identification of malaria vectors and genetic marker classification in relation to their use for species identification. Due to its specificity and consistency, molecular identification is preferred over morphological identification of malaria vectors. Enhanced molecular capacity for species identification will improve mosquito characterization, leading to accurate control strategies/treatment targeting specific mosquito species, and thus will contribute to malaria eradication. It is crucial for disease epidemiology and surveillance to accurately identify the Plasmodium spp. that are causing malaria in patients. The capacity for disease surveillance will be significantly increased by the development of more accurate, precise, automated, and high-throughput diagnostic techniques. In conclusion, although morphological identification is quick and achievable at a reduced cost, molecular identification is preferred for specificity and sensitivity. To achieve the targeted malaria elimination goal, proper identification of vectors using accurate techniques for effective control measures should be prioritized.
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Camels (Camelus dromedarius) in Africa are adapted to arid and the semi-arid environmental conditions, and are valuable for meat, milk and fiber production. On account of the growing demand for camels in this continent, there is a need for knowledge on their phenotypic and genetic diversity. This is fundamental to sustainable herd management and utilization including the design of appropriate breeding and conservation strategies. We reviewed studies on the phenotypic and genetic characterization, breeding objectives, systems of production, productive and reproductive performances, and pathways for the sustainable rearing and use of camels in Africa. The morphological and genetic diversity, productive and reproductive abilities of African camels suggest the existence of genetic variations that can be utilized for breeds/ecotypes' genetic improvement and conservation. Possible areas of intervention include the establishment of open nucleus and community-based breeding schemes and utilization of modern reproductive technologies for the genetic improvement of milk and meat yields, sustainable management of rangelands, capacity building of the pastoralists and agro-pastoralists, institutional supports, formation of centralized conservation centres and efficient and effective marketing systems.
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Monkeypox is a zoonotic viral disease that has recently emerged as another global infection disease. A double-stranded enveloped deoxyribonucleic acid virus the cause of this disease. Since monkeypox is an evolving field of study with a growing interest in public health, it is crucial to study the scientific trend and research activities. This study provides an essential insight into the research response to scientific trends of monkeypox using the bibliometric analysis technique. A literature search for published articles on LSD from 2001 to 2021 was conducted in Scopus on 24 July 2022. Visualization analysis was performed using R statistical software. The growth and trend of documents, country-level distribution of publications and collaborations, and the relationship between authors and co-authors were analyzed. Findings revealed a significant increase in the research conducted, mainly from the United States (US). The top 12 institutions published papers on the monkeypox virus, accounting for 33.09 percent of the articles. The US was the most productive nation, producing 275 documents (54.34%), or one-third of all publications in this sector worldwide. Centers for Disease Control and Prevention in Georgia in the United States were the organization that produced the most (365 publications). The Journal of Virology garnered the most citations, with an h-index of 18. In the last year, there has been an increase in the publication of monkeypox virus-related studies. The importance of the monkeypox virus highlights the necessity for continued research to help international health organizations identify areas that require prompt action to implement suitable solutions. This study also provides scaling-up analysis, evidence dissemination on the monkeypox virus, emerging hotspots, and perceptive remarks on the technological advances in this field.
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Background and Aim: Global warming has grave consequences on livestock production systems and profound negative effects on animal production. This study aimed to carry out an in vitro thermal stress stimulation (TSS) of bovine peripheral blood mononuclear cells (PBMCs) using different thermal assault conditions (TACs), including normal to extreme temperatures and varying durations of thermal exposure (DTE) to understand how PBMCs of Indian Zebu-Jersey crossbreds respond to various levels and durations of heat shock. Materials and Methods: Ten milliliters of blood were collected from 70 Indian Zebu-Jersey crossbreds under aseptic conditions and were sampled for isolating PBMCs. Peripheral blood mononuclear cells were divided into seven groups, each comprising 10 PBMC samples isolated from 10 different animals. Aliquots of 500 µL of PBMCs were stressed by exposure to different TACs (37, 40, and 45°C) for DTEs of 3 or 6 h. Subsequently, the cells were harvested. The control unstressed samples (500 µL aliquots of PBMCs) were exposed to no TAC (0°C) and zero DTE (0 h). Total RNA from all the treatment groups of PBMCs were isolated and quantitated. Results: We found a very strong association between TACs and RNA levels. In addition, PBMCs viability was negatively affected by heat shock. This led to an exponential reduction in PBMC count as TACs toughened. Only 3.59 × 105 ± 0.34 cells/mL were viable after exposure to 45°C for a 6 h DTE. This cell viability was lower than that measured in controls subjected to no stress and zero time DTE (2.56 × 107 ± 0.22 cells/mL). We also observed a reduction in the concentration of RNA isolated from thermally stressed PBMCs. Conclusion: In vitro TSS of PBMCs provided biological information on the response of cellular systems to heat shock after exposure to TACs. This will help to mitigate and manage the effects of thermal stress in bovine species. The association between the reduction in PBMC count after in vitro TSS and the expression of heat shock protein 70 gene will be investigated in the future to further understand how Indian Zebu-Jersey crossbreds respond to in vitro thermal conditions. This will be used to determine the in vivo response of Indian Jersey crossbreds to different environmental thermal conditions and will further enable the in vivo understanding of thermotolerance potentials of bovine species for better adaptation, survival, and production performance.