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- Bovine testicular heat stress: From climate change to effects on microRNA profile
Anim Reprod Sci. 2024 Oct 11;270:107620. doi: 10.1016/j.anireprosci.2024.107620. Online ahead of print.
ABSTRACT
Heat stress is caused by exposure of animals to high temperatures and humidity, outside their thermal comfort zone. This can have negative outcomes, including adversely affecting general well-being and reducing productive and reproductive performance. In males, heat stress can disrupt testicular thermoregulation, with deleterious effects on spermatogenesis and consequently, decreases in sperm quality and fertility potential. Thus, high environmental temperature is considered one of the most important factors that predisposes bulls to subfertility and has already been the subject of many studies, particularly in tropical or subtropical countries. It is essential to study effects of testicular heat stress in bulls, know the chronology of clinical and sperm findings, and understand the underlying pathophysiology. In addition, elucidating molecular mechanisms involved in heat stress and testicular function could provide the basis for effective, evidence-based strategies for selecting more thermotolerant animals. Excessive heat affects expression of messenger RNA (mRNA) and microRNA (miRNA) in sperm, which have important roles in regulating male fertility. Based on current trends in climate change, the incidence of chronically high temperatures that cause heat stress is expected to increase, posing increasing risks to health and survival of many species. The study of mRNAs and miRNAs can provide valuable insights to select animals that are more resilient to climate change. In addition to the search for more thermotolerant animals, other strategies to mitigate effects of heat stress include reproductive biotechniques and promotion of a better environment.
PMID:39426075 | DOI:10.1016/j.anireprosci.2024.107620
- Long non-coding RNA (LncRNA) and epigenetic factors: their role in regulating the adipocytes in bovine
Front Genet. 2024 Oct 3;15:1405588. doi: 10.3389/fgene.2024.1405588. eCollection 2024.
ABSTRACT
Investigating the involvement of long non-coding RNAs (lncRNAs) and epigenetic processes in bovine adipocytes can provide valuable new insights into controlling adipogenesis in livestock. Long non-coding RNAs have been associated with forming chromatin loops that facilitate enhancer-promoter interactions during adipogenesis, as well as regulating important adipogenic transcription factors like C/EBPα and PPARγ. They significantly influence gene expression regulation at the post-transcriptional level and are extensively researched for their diverse roles in cellular functions. Epigenetic modifications such as chromatin reorganization, histone alterations, and DNA methylation subsequently affect the activation of genes related to adipogenesis and the progression of adipocyte differentiation. By investigating how fat deposition is epigenetically regulated in beef cattle, scientists aim to unravel molecular mechanisms, identify key regulatory genes and pathways, and develop targeted strategies for modifying fat deposition to enhance desirable traits such as marbling and meat tenderness. This review paper delves into lncRNAs and epigenetic factors and their role in regulating bovine adipocytes while focusing on their potential as targets for genetic improvement to increase production efficiency. Recent genomics advancements, including molecular markers and genetic variations, can boost animal productivity, meeting global demands for high-quality meat products. This review establishes a foundation for future research on understanding regulatory networks linked to lncRNAs and epigenetic changes, contributing to both scholarly knowledge advancement and practical applications within animal agriculture.
PMID:39421300 | PMC:PMC11484070 | DOI:10.3389/fgene.2024.1405588
- A systematic review and meta-analysis of bovine tuberculosis occurrence and burden in Bangladesh, 1970-2023
Epidemiol Infect. 2024 Oct 17;152:e126. doi: 10.1017/S0950268824001328.
ABSTRACT
We aimed to estimate the overall apparent prevalence, true prevalence, and the spatial, temporal, and test-specific burden of bovine tuberculosis in Bangladesh. PubMed, Web of Science, Scopus, Google Scholar, and BanglaJOL were searched for bovine tuberculosis publications in Bangladesh from 1 January 1970 to 23 June 2023. Of 142 articles screened, systematic review and meta-analysis were performed on 22 (15.5%) articles. The apparent estimated bovine tuberculosis prevalence was 7%. The apparent Bayesian pooled mean bovine tuberculosis prevalences based on caudal fold test and single intradermal comparative tuberculin test were 7.83% and 9.89%, respectively, and the true pooled mean prevalences were 10.39% and 10.48%, respectively. Targeted interventions are recommended for districts with higher prevalence to effectively reduce the bovine tuberculosis burden in those areas. Current diagnostic practices employed in Bangladesh may not accurately reflect the bovine tuberculosis burden. Our findings highlight the need for better diagnostic tools and supplemental testing methods to ensure accurate diagnosis and surveillance. Efforts should prioritize obtaining ‘true’ prevalence estimates corrected for misclassification bias, rather than relying solely on apparent prevalence. Underestimating the bovine tuberculosis burden could result in inadequate resource allocation and hinder the implementation of effective control measures.
PMID:39417391 | DOI:10.1017/S0950268824001328
- Technologies and Solutions for Cattle Tracking: A Review of the State of the Art
Sensors (Basel). 2024 Oct 9;24(19):6486. doi: 10.3390/s24196486.
ABSTRACT
This article presents a systematic literature review of technologies and solutions for cattle tracking and monitoring based on a comprehensive analysis of scientific articles published since 2017. The main objective of this review is to identify the current state of the art and the trends in this field, as well as to provide a guide for selecting the most suitable solution according to the user’s needs and preferences. This review covers various aspects of cattle tracking, such as the devices, sensors, power supply, wireless communication protocols, and software used to collect, process, and visualize the data. The review also compares the advantages and disadvantages of different solutions, such as collars, cameras, and drones, in terms of cost, scalability, precision, and invasiveness. The results show that there is a growing interest and innovation in livestock localization and tracking, with a focus on integrating and adapting various technologies for effective and reliable monitoring in real-world environments.
PMID:39409526 | PMC:PMC11479337 | DOI:10.3390/s24196486
- Predicting Microbial Protein Synthesis in Cattle: Evaluation of Extant Equations and Steps Needed to Improve Accuracy and Precision of Future Equations
Animals (Basel). 2024 Oct 9;14(19):2903. doi: 10.3390/ani14192903.
ABSTRACT
Predictions of microbial crude protein (MCP) synthesis for beef cattle generally rely on empirical regression equations, with intakes of energy and protein as key variables. Using a database from published literature, we developed new equations based on the intake of organic matter (OM) and intakes or concentrations of crude protein (CP) and neutral detergent fiber (NDF). We compared these new equations to several extant equations based on intakes of total digestible nutrients (TDN) and CP. Regression fit statistics were evaluated using both resampling and sampling from a simulated multivariate normal population. Newly developed equations yielded similar fit statistics to extant equations, but the root mean square error of prediction averaged 155 g (28.7% of the mean MCP of 540.7 g/d) across all equations, indicating considerable variation in predictions. A simple approach of calculating MCP as 10% of the TDN intake yielded MCP estimates and fit statistics that were similar to more complicated equations. Adding a classification code to account for unique dietary characteristics did not have significant effects. Because MCP synthesis is measured indirectly, most often using surgically altered animals, literature estimates are relatively few and highly variable. A random sample of individual studies from our literature database indicated a standard deviation for MCP synthesis that averaged 19.1% of the observed mean, likely contributing to imprecision in the MCP predictions. Research to develop additional MCP estimates across various diets and production situations is needed, with a focus on developing consistent and reliable methodologies for MCP measurements. The use of new meta-omics tools might improve the accuracy and precision of MCP predictions, but further research will be needed to assess the utility of such tools.
PMID:39409852 | PMC:PMC11475687 | DOI:10.3390/ani14192903
- Volumetric lesion analysis and validation of various bipolar configurations in radiofrequency ablation of ventricular myocardium in a bovine model
J Interv Card Electrophysiol. 2024 Oct 14. doi: 10.1007/s10840-024-01927-3. Online ahead of print.
ABSTRACT
BACKGROUND: The bipolar radiofrequency ablation(B-RFA) strategy was increasingly used to target deep intramural re-entrant foci responsible for the arrhythmia not ablated by conventional unipolar RFA / sequential unipolar RFA. Lesional characteristics of various bipolar configurations were largely unknown.
OBJECTIVE: To investigate the lesional geometry in relation to various factors to determine the most effective ablation strategy that minimises steam pops and achieves transmurality. To assess the temperatures at the return electrode.
METHODS: A custom-made validated ex-vivo bipolar ablation model was used to assess lesion formation. The myocardial sample was placed between two ablation catheters in four different orientations. Lesions were created using different power (30 W, 40 W, 50 W) and time settings(30, 40 and 50 s) with different catheter orientations. Data was analysed using binary logistic regression and multiple linear regression.
RESULTS: Among 107 lesions, The volume of the active catheter lesion (266 +/- 137 mm^3) significantly differed from their return electrode counterparts (130 +/- 91.8 mm^3) (p < 0.001), and the temperatures at the return electrode end were lower than at the active electrode (p = 0.004). Higher power and longer duration application led to more frequent steam pops (p < 0.001), while true parallel configuration resulted in fewer steam pops (p < 0.001).
CONCLUSION: A custom model without ground electrode temperature monitoring is safe and cost-effective. The safest strategy is a true parallel configuration with an inter-electrode distance of at least 15 mm and a power of 30 W to 40 W, which generates lower steam pops and better transmurality.
PMID:39400645 | DOI:10.1007/s10840-024-01927-3
- Methodological approaches in vitrification: Enhancing viability of bovine oocytes and in vitro-produced embryos
Reprod Domest Anim. 2024 Oct;59 Suppl 3:e14623. doi: 10.1111/rda.14623.
ABSTRACT
Cryopreservation of bovine oocytes and embryos is essential for long-term preservation and widespread distribution of genetic material, particularly in bovine in vitro embryo production, which has witnessed substantial growth in the past decade due to advancements in reproductive biotechnologies. Among current cryopreservation methods, vitrification has emerged as the preferred cryopreservation technique over slow freezing for preserving oocytes and in vitro-produced (IVP) embryos, as it effectively addresses membrane chilling injury and ice crystal formation. Nonetheless, challenges remain and a simple and robust vitrification protocol that guarantees the efficiency and viability after warming has not yet been developed. Furthermore, although slow cooling can easily be adapted for direct transfer, an easier and more practical vitrification protocol for IVP embryos is required to allow the transfer of IVP embryos on farms using in-straw dilution. In addition, the susceptibility of bovine oocytes and embryos to cryoinjuries highlights the need for novel strategies to improve their cryotolerance. This manuscript examines various methodological approaches for increasing the viability of bovine oocytes and IVP embryos during vitrification. Strategies such as modifying lipid content or mitigating oxidative damage have shown promise in improving cryotolerance. Additionally, mathematical modelling of oocyte and embryo membrane permeability has facilitated the rational design of cryopreservation protocols, optimizing the exposure time and concentration of cryoprotectants to reduce cytotoxicity.
PMID:39396876 | DOI:10.1111/rda.14623
- Global prevalence of Cryptosporidium andersoni in dairy cattle: A systematic review and meta-analysis
Acta Trop. 2024 Oct 9;260:107427. doi: 10.1016/j.actatropica.2024.107427. Online ahead of print.
ABSTRACT
Cryptosporidium spp. are apicomplexan parasites commonly found in the gastrointestinal tracts of humans and in a wide range of animals. Infection is prevalent in dairy cattle and results in diarrhea and increased mortality with significant production losses. Cryptosporidium andersoni is commonly seen in asymptomatic adult cattle and has been associated with gastritis, reduced milk yield, and poor weight gain. However, a meta-analysis of C. andersoni infection in dairy cattle globally has not yet been published. We searched databases for studies on the global prevalence of C. andersoni infection in dairy cattle published from January 1, 2000, to December 31, 2022. The prevalence of C. andersoni infection in dairy cattle was estimated using a random effects model. In total, 86 publications from 30 countries were included in the final quantitative analysis. The global prevalence of C. andersoni in dairy cattle was 4.7 % (95 % confidence interval [CI]: 4.5-4.9 %, 2,554/54,627). European dairy cattle had the highest rate of C. andersoni infection at 8.8 % (961/10,944). A univariate meta-regression analysis indicated that the age of cattle (P = 0.002) and sample collection year (P = 0.025) might be sources of heterogeneity. This systematic review suggests that globally, dairy cattle exhibit a low level of C. andersoni infection; however, the geographical distribution of infection is extensive. C. andersoni mainly infects the stomach of cattle and causes no obvious clinical symptoms after infection but is thought to be responsible for reduced milk production. Therefore, subclinical Cryptosporidium infection in dairy cattle is easily overlooked. Cattle with subclinical infections can produce feces containing oocysts that are inadvertently not safely handled, which can then infect healthy dairy cattle and even cause Cryptosporidium infection in dairy cattle breeders. Therefore, prevention of C. andersoni transmission in asymptomatic cattle is an important issue that should not be neglected.
PMID:39393480 | DOI:10.1016/j.actatropica.2024.107427
- INVITED REVIEW: Phenotyping strategies and genetic background of dairy cattle behavior in intensive production systems – from trait definition to genomic selection
J Dairy Sci. 2024 Oct 8:S0022-0302(24)01202-5. doi: 10.3168/jds.2024-24953. Online ahead of print.
ABSTRACT
Understanding and assessing dairy cattle behavior is critical for developing sustainable breeding programs and management practices. The behavior of individual animals can provide valuable information on their health and welfare status, improve reproductive management, and predict efficiency traits such as feed efficiency and milking efficiency. Routine genetic evaluations of animal behavior traits can contribute to optimizing breeding and management strategies for dairy cattle but require the identification of traits that capture the most important biological processes involved in behavioral responses. These traits should be heritable, repeatable, and measured in non-invasive and cost-effective ways in many individuals from the breeding populations or related reference populations. While behavior traits are heritable in dairy cattle populations, they are highly polygenic, with no known major genes influencing their phenotypic expression. Genetically selecting dairy cattle based on their behavior can be advantageous because of their relationship with other key traits such as animal health, welfare, and productive efficiency, as well as animal and handlers’ safety. Trait definition and longitudinal data collection are still key challenges for breeding for behavioral responses in dairy cattle. However, the more recent developments and adoption of precision technologies in dairy farms provide avenues for more objective phenotyping and genetic selection of behavior traits. Furthermore, there is still a need to standardize phenotyping protocols for existing traits and develop guidelines for recording novel behavioral traits and integrating multiple data sources. This review gives an overview of the most common indicators of dairy cattle behavior, summarizes the main methods used for analyzing animal behavior in commercial settings, describes the genetic and genomic background of previously defined behavioral traits, and discusses strategies for breeding and improving behavior traits coupled with future opportunities for genetic selection for improved behavioral responses.
PMID:39389298 | DOI:10.3168/jds.2024-24953
- Genotype-by-environment interactions in beef and dairy cattle populations: A review of methodologies and perspectives on research and applications
Anim Genet. 2024 Oct 8. doi: 10.1111/age.13483. Online ahead of print.
ABSTRACT
Modern livestock production systems are characterized by a greater focus on intensification, involving managing larger numbers of animals to achieve higher productive efficiency and animal health and welfare within herds. Therefore, animal breeding programs need to be strategically designed to select animals that can effectively enhance production performance and animal welfare across a range of environmental conditions. Thus, this review summarizes the main methodologies used for assessing the levels of genotype-by-environment interaction (G × E) in cattle populations. In addition, we explored the importance of integrating genomic and phenotypic information to quantify and account for G × E in breeding programs. An overview of the structure of cattle breeding programs is provided to give insights into the potential outcomes and challenges faced when considering G × E to optimize genetic gains in breeding programs. The role of nutrigenomics and its impact on gene expression related to metabolism in cattle are also discussed, along with an examination of current research findings and their potential implications for future research and practical applications. Out of the 116 studies examined, 60 and 56 focused on beef and dairy cattle, respectively. A total of 83.62% of these studies reported genetic correlations across environmental gradients below 0.80, indicating the presence of G × E. For beef cattle, 69.33%, 24%, 2.67%, 2.67%, and 1.33% of the studies evaluated growth, reproduction, carcass and meat quality, survival, and feed efficiency traits, respectively. By contrast, G × E research in dairy cattle populations predominantly focused on milk yield and milk composition (79.36% of the studies), followed by reproduction and fertility (19.05%), and survival (1.59%) traits. The importance of G × E becomes particularly evident when considering complex traits such as heat tolerance, disease resistance, reproductive performance, and feed efficiency, as highlighted in this review. Genomic models provide a valuable avenue for studying these traits in greater depth, allowing for the identification of candidate genes and metabolic pathways associated with animal fitness, adaptation, and environmental efficiency. Nutrigenetics and nutrigenomics are emerging fields that require extensive investigation to maximize our understanding of gene-nutrient interactions. By studying various transcription factors, we can potentially improve animal metabolism, improving performance, health, and quality of products such as meat and milk.
PMID:39377556 | DOI:10.1111/age.13483