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More than one-half of the world’s cattle are maintained in hot environments, making heat stress a significant issue for the beef industry. Around $370 million is lost annually due to reduced performance due to heat stress, which has other detrimental impacts on cattle, such as decreased feed intake, fertility, and immune response. The assessment of hair glucocorticoids (hGC) serves as a valuable tool for evaluating chronic stress levels in beef cattle. Unlike traditional cortisol measurements, which provide only a glimpse of stress at a specific moment, hGCs offer a retrospective view of long-term stress exposure. This makes them particularly valuable for assessing chronic stress, which can profoundly impact animal health, welfare, and productivity. By quantifying hGC concentrations, we gain insights into the cumulative stress experienced by cattle over time, allowing for more comprehensive monitoring and management strategies. This study investigated the relationship between hGC concentrations and breed composition in beef cattle, specifically focusing on whether breed composition influences hGC concentrations after prolonged heat exposure. Animals from the University of Florida’s Multibreed Angus-Brahman herd were used. Hair samples were collected from 240 cows during the summer of 2017 and 2018, with breed compositions ranging from 100% Brahman to 100% Angus. Starting with a 4 mg hair sample, the hGC were extracted and analyzed with the Cortisol ELISA KIT (Neogen Corporation, Ayr, UK). An Analysis of Variance (ANOVA) was conducted to examine the relationship between hGC concentration, breed composition, and batch effect. The results indicated a significant effect of breed composition on hGC concentration (P-value 0.01406). These findings suggest that breed composition influences chronic stress during prolonged periods of heat exposure. However, individual factors like thermotolerance, health status, and social stress may also have a role in chronic stress levels. To better understand these factors, future steps will involve comparing the hGC concentration results between thermotolerant and non-thermotolerant animals. This comparison will provide insights into the potential differences in stress responses between cattle breeds adapted to hot environments and those less tolerant to heat stress. [ABSTRACT FROM AUTHOR]

In subtropical and tropical environments, beef cattle production faces significant challenges due to heat stress, affecting animal welfare and productivity. To mitigate these effects, producers have turned to crossbreeding and the development of composite breeds like Brangus, which combine the desirable carcass and meat quality traits of European taurine cattle with the thermotolerance of Indicine breeds. However, the genetic underpinnings of thermotolerance in these composite populations are not well understood, owing to the complex nature of measuring related traits and the genetic intricacies arising from crosses of distinct populations. This study aims to identify key quantitative trait loci (QTL) related to thermotolerance, employing an approach that integrates genetic markers alongside the marker’s breed of origin of alleles (BOA) in Brangus heifers. Data were collected on histological sweat gland area (SWA), hair length (HL), and thermal stress slope as a measure of the increase in body temperature from a low to a high temperature-humidity index (TSS), from 2,233 Brangus heifers genotyped with the 250K functional chip. BOA was determined using LAMP-LD software, using Angus and Brahman cattle from the University of Florida’s multibreed Angus-Brahman project as a reference population. We conducted a genome-wide association study (GWAS) incorporating BOA-specific effects, revealing several genes with BOA-specific effects. Notably, the CGGBP1 gene exhibited a significant effect on TSS only when alleles originated from Brahman. Conversely, the PLK1 gene was significant for TSS when alleles originated from Angus. Both CGGBP1 and PLK1 interact with heat shock proteins during heat stress, these findings reveal different genetic mechanisms for controlling internal body temperature. For HL, a significant Brahman-specific effect was found near the PRLR gene, which is known as the gene controlling the SLICK hair phenotype in Criollo cattle. For SWA, an Angus-specific significant association was found with the PDE4D gene. PDE4D interacts with the cAMP pathway which regulates sweat gland growth and sweat production. These findings underline the genetic complexity of thermotolerance in composite cattle and the crucial role of BOA in identifying key QTL. The study offers novel insights into the genetic mechanisms of thermotolerance, providing a foundation for breeding strategies aimed at improving heat resilience in cattle in subtropical and tropical environments. [ABSTRACT FROM AUTHOR]

Bioinformatics, an emerging powerful science gradually enfolds all sorts of sciences under its huge banner; Forensic Sciences being one of them. With the passing time the productiveness, efficacy and virtue of Bioinformatics based tools is taking over the Forensic Sciences and research. Whether it be declaration via extracting the tiniest DNA from the tiniest microbial sample, DNA profiling, gender identification or the most advanced Automatic Fingerprint Recognition System, computational tools are aiding the Forensics in every possible way. Furthermore, Next Generation Sequencing technology along with the epigenetic studies gives rise to a vast research domain by simultaneously analyzing multiple loci that are of forensic interest in multiple genetic contexts. The paper evaluates then boosting influence of computation on this immensely significant field, especially in terms of law and order. A series of physical evidences are put up for the critical analysis that reveal pros and cons and definitely the efficacy of the techniques that are being implemented including DNA profiles, STR profiles, AFSR algorithms, sequencing, computer review, storing DNA evidence, Next Generation Sequencing and others. [ABSTRACT FROM AUTHOR]