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  • Infectious bovine rhinotracheitis: Unveiling the hidden threat to livestock productivity and global trade

    Open Vet J. 2024 Oct;14(10):2525-2538. doi: 10.5455/OVJ.2024.v14.i10.3. Epub 2024 Oct 31.

    ABSTRACT

    An infectious disease called infectious bovine rhinotracheitis (IBR) can lead to a number of disorders affecting cattle’s respiratory system. The disease is caused by bovine alphaherpesvirus type 1 (BoAHV-1). Based on antigenic and genetic characteristics, BoAHV-1 strains are divided into subtypes 1.1, 1.2a, 1.2b, and 1.3. IBR is currently widespread throughout the world, with the exception of a few nations that have achieved eradication. The most significant characteristic of this illness is that, after a clinical or subclinical infection, the virus typically establishes a latent condition that can later be reactivated in the presence of stress, immunosuppressive conditions/substances, or other diseases. Primarily, the virus spreads by direct or indirect contact between animals. It may also be transmitted via the reproductive system, causing infectious balanoposthitis or vulvovaginitis. Most virus subtypes are associated with reproductive failure, such as fetal or embryonic resorption and abortions. The virus may also be transmitted through semen, which could lead to genital transfer. Bovine herpesvirus type 1 (BoHV-1) infection produces a variety of lesions. Lesion in the mucosal surface usually consists of white necrotic material. Regular methods for diagnosing BoHV-1 infections include isolation in cell culture, enzyme linked immunosorbent assay, virus neutralisation test, and methods based on identification of nucleic acids, like PCR. The interplay of several host, pathogen, environmental, and management factors affects the spread of IBR. Through its impacts on health and fitness, IBR can lead to production losses. In order to minimize the severity of clinical signs and stop the infection from spreading, the veterinarian may advise that sick or at-risk animals be placed under immediate isolation and vaccinated (such as intranasal vaccination, including the use of both killed and live attenuated virus vaccines) as soon as an IBR diagnosis is obtained.

    PMID:39545192 | PMC:PMC11560271 | DOI:10.5455/OVJ.2024.v14.i10.3

  • Cow's milk protein allergy in infants and children

    Paediatr Child Health. 2024 Nov 12;29(6):382-396. doi: 10.1093/pch/pxae043. eCollection 2024 Sep.

    ABSTRACT

    Cow’s milk protein allergy (CMPA) is an immune-mediated reaction to cow’s milk proteins, which can involve multiple organ systems including the gastrointestinal tract. Immunoglobulin E (IgE)-mediated response results in rapid onset of allergic symptoms that are easily recognizable. However, delayed (i.e., non-IgE/cell-mediated) or mixed (IgE- and cell-mediated) reactions produce a host of symptoms that overlap with other conditions and vary widely in onset and severity. Determining whether symptoms represent immune-mediated CMPA, non-immunologic reaction to cow’s milk, or are unrelated to cow’s milk exposure is challenging yet essential for effective management. While the clinical presentation of non-IgE-mediated CMPA can vary, this condition is usually self-limited and resolves by 1 to 6 years of age. Food antigen-specific immunoglobulin G (IgG) panels that are not evidence-based should be avoided because they can lead to overdiagnosis of presumed food intolerances. Overdiagnosis of CMPA can result in overuse of extensively hydrolyzed formulas and have significant cost implications for families. This statement focuses on delayed non-IgE/cell-mediated CMPA and assists health care providers to distinguish between and identify varied reactions to cow’s milk, discusses the role of diagnostic testing, and provides management recommendations based on best evidence.

    PMID:39539784 | PMC:PMC11557147 | DOI:10.1093/pch/pxae043

  • Avian influenza A (H5N1) virus in dairy cattle: origin, evolution, and cross-species transmission

    mBio. 2024 Nov 13:e0254224. doi: 10.1128/mbio.02542-24. Online ahead of print.

    ABSTRACT

    Since the emergence of highly pathogenic avian influenza virus (HPAIV) H5N1 of clade 2.3.4.4b as a novel reassortant virus from subtype H5N8, the virus has led to a massive number of outbreaks worldwide in wild and domestic birds. Compared to the parental HPAIV H5N8 clade 2.3.4.4b, the novel reassortant HPAIV H5N1 displayed an increased ability to escape species barriers and infect multiple mammalian species, including humans. The virus host range has been recently expanded to include ruminants, particularly dairy cattle in the United States, where cattle-to-cattle transmission was reported. As with the avian 2.3.4.4.b H5N1 viruses, the cattle-infecting virus was found to transmit from cattle to other contact animals including cats, raccoons, rodents, opossums, and poultry. Although replication of the virus in cows appears to be mainly confined to the mammary tissue, with high levels of viral loads detected in milk, infected cats and poultry showed severe respiratory disease, neurologic signs, and eventually died. Furthermore, several human infections with HPAIV H5N1 have also been reported in dairy farm workers and were attributed to exposures to infected dairy cattle. This is believed to represent the first mammalian-to-human transmission report of the HPAIV H5N1. Fortunately, infection in humans and cows, as opposed to other animals, appears to be mild in most cases. Nevertheless, the H5N1 bovine outbreak represents the largest outbreak of the H5N1 in a domestic mammal close to humans, increasing the risk that this already mammalian adapted H5N1 further adapts to human-to-human transmission and starts a pandemic. Herein, we discuss the epidemiology, evolution, pathogenesis, and potential impact of the recently identified HPAIV H5N1 clade 2.3.4.4b in dairy cattle in the United States. Eventually, interdisciplinary cooperation under a One Health framework is required to be able to control this ongoing HPAIV H5N1 outbreak to stop it before further expansion of its host range and geographical distribution.

    PMID:39535188 | DOI:10.1128/mbio.02542-24

  • North American perspectives for cattle production and reproduction for the next 20 years

    Theriogenology. 2024 Nov 6;232:109-116. doi: 10.1016/j.theriogenology.2024.11.006. Online ahead of print.

    ABSTRACT

    Ruminant species are important to human society due to their ability to convert human-inedible sources of energy and protein to human-edible food. Greater efficiency of meat and milk production will require the management of the complex reproductive biology of many cattle with a limited capacity and limited budget within a smaller, hotter, and more climatically erratic land area. The over-riding drivers of new reproductive technologies in North America will be smaller economic margins, larger herd size, fewer agricultural workers per farm, and a greater reliance on automation to offset the reduced agricultural labor force. Climate change and the possibility that consumers may dictate the procedures used for animal reproductive management may present additional challenges. The successes of the past 20 years (timed AI, genomic selection for fertility in both bulls and cows, automated estrus detection, chemical and ultrasonographic pregnancy diagnosis, and gender selected semen) will be improved upon in the next 20 years as most of these technologies can be optimized further. Improving embryo technologies and increasing our understanding of embryonic loss may provide the greatest challenges for the future. Researchers must attempt to devise practical methods to release more follicles from the primordial follicle pool so that a greater number of oocytes and embryos can be harvested from individual animals. Embryonic loss continues to be an unsolved question that cuts the total number of potential offspring by nearly one-third. The identification of fertile embryos in vitro, better methods of cryopreservation, and the optimization of methods of transfer into recipient animals may improve the efficiency of advanced embryo technologies. The derivation of oocytes, sperm, and embryos from pluripotent stem cells may yield a vast supply of gametes and embryos from genetically superior animals and radically change the reproductive management in the future.

    PMID:39536622 | DOI:10.1016/j.theriogenology.2024.11.006

  • Looking Inside of the Intestinal Permeability Regulation by Protein-Derivatives from Bovine Milk

    Mol Nutr Food Res. 2024 Nov 12:e2400384. doi: 10.1002/mnfr.202400384. Online ahead of print.

    ABSTRACT

    The prime function of the epithelium is to regulate the intestinal permeability; the latter is a quantitative parameter that refers to the measurement of the rate of passage of solutes through the epithelial monolayer. Function of epithelial monolayer depends on the expression of protein complexes known as tight junction proteins; whose function and expression can be disrupted under conditions of inflammation including irritable bowel disease (IBD), intestinal infections, and high-fat diets, among others. This manuscript is focused to outline the effects of bovine milk protein derivatives on the intestinal permeability addressed mostly in animal models in which the intestinal barrier is disrupted. At present, the properties of bovine milk protein derivatives on intestinal permeability have been scarcely documented in humans, but evidence raised from clinical trials provides promising findings of potential application of colostrum to control of the intestinal permeability in critically ill patients, users of non-steroid anti-inflammatory drugs, like athletes and militia members.

    PMID:39530631 | DOI:10.1002/mnfr.202400384

  • Ruminating on Bovine Implantation: Its Importance in Fertility, Food Production, Conservation, and Health

    Annu Rev Anim Biosci. 2024 Nov 12. doi: 10.1146/annurev-animal-111523-102403. Online ahead of print.

    ABSTRACT

    Implantation in cattle is a key developmental checkpoint for pregnancy success. It involves careful spatiotemporal changes to the transcriptional landscape of the endometrium, with the heterogeneous nature of the endometrium increasing the complexity of understanding of the mechanism involved. Implantation is impacted by the developmental competency of the embryo, use of assisted reproductive technologies, and the environment in which this process occurs. We identify the factors that most impact the implantation process in cattle and highlight how it differs with that in other placental mammals. We propose the major areas that lack evidence are the mechanism(s) by which implantation itself occurs and how different stressors alter this process. Our understanding is hindered by a lack of appropriate in vitro models; however, development of novel 3D tools and available data sets will further elucidate the implantation process. Perhaps more importantly, this will develop methods to mitigate against these stressors to improve implantation success and offspring health.

    PMID:39531737 | DOI:10.1146/annurev-animal-111523-102403

  • The problem that residual Mycobacterium bovis infection poses for the eradication of bovine tuberculosis

    Vet J. 2024 Nov 9;308:106266. doi: 10.1016/j.tvjl.2024.106266. Online ahead of print.

    ABSTRACT

    The dynamics of Mycobacterium bovis infection in cattle can influence the proportion of infected animals that are diagnosed by ante-mortem tests in routine bovine tuberculosis (bTB) surveillance and monitoring programmes. Although the current diagnostic tests based on cell-mediated or serological responses are imperfect, they are effective in diagnosing the majority of infected animals. However, the lack of perfect sensitivity and specificity also leads to failure to diagnose all infected animals leading to persistence of infection in herds. The terms residual, subclinical, latent and anergy have been used interchangeably to denote the presence of continued undiagnosed M. bovis infection within cattle herds, which ultimately hinders the eradication of bTB and imposes substantial financial burdens on farming communities and national economies. Epidemiological data suggests the existence of M. bovis-infected, but often undetected, cattle within herds that contribute to eradication failure. This has similarities with human tuberculosis, caused by Mycobacterium tuberculosis, where latent infection is defined as the persistence of viable but quiescent bacilli for extended periods in patients without clinical symptoms but with a detectable immune response to M. tuberculosis antigens. If a similar infection state exists in cattle infected with M. bovis, the persistence of such animals in disease-managed herds is unlikely to be common given that those found to have positive immune responses to M. bovis antigens are routinely culled to minimise future risk of transmission. Apart from contributing to the burden of herd infection, such residual infection without detection may also ‘seed’ recipient herds following animal movements, and potentially play an important role in the overall epidemiology of bTB as the prevalence of disease decreases and the attendant altered predictive value of the diagnostic tests result in a greater proportion of infected animals remaining undetected. This review examines how the different stages of M. bovis infection in cattle may contribute to the failure to diagnose infected animals using conventional testing methodologies and the attendant risk this poses in creating prolonged or recurrent herd breakdowns.

    PMID:39528077 | DOI:10.1016/j.tvjl.2024.106266

  • Epidemiology, risk factors and vector density of trypanosomosis in cattle in Ethiopia: Systematic review and meta-analysis

    Parasite Epidemiol Control. 2024 Oct 23;27:e00388. doi: 10.1016/j.parepi.2024.e00388. eCollection 2024 Nov.

    ABSTRACT

    BACKGROUND: Bovine trypanosomosis remains a major barrier to livestock productivity, agricultural progress, and socioeconomic development in Ethiopia’s large tsetse belt regions, threatening 70 million cattle. Therefore, this review examined published literature from the last ten years to estimate the pooled prevalence, risk factors, and vector density of bovine trypanosomosis. This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, using PubMed, Web of Science, HINARI, Google, and Google Scholar. Pooled prevalence and risk factors were calculated with a random effects model in R software, with a 95 % confidence interval. This meta-analysis included research published after 2015 on trypanosomosis in Ethiopian cattle, where Trypanosoma was classified at least to the genus level. Studies on other species, lacking specific prevalence data and published before 2015 were excluded.

    RESULTS: A total of 26 articles were included in this meta-analysis. The overall pooled proportion of bovine Trypanosomosis cases was 9 % (95 % CI: 8-9 %). Considerable heterogeneity was observed across the included studies (I2 = 94 %; P < 0.01). The highest pooled prevalence of trypanosomosis was reported in Amhara and Oromia (8 %), followed by Benishangul Gumuz (BSGR) (7 %). Based on the subspecies analysis, the highest pooled proportion was 65 % (95 % CI: 58 %-71 %) for T. congolense (I2 = 81 %: p = 0.01), followed by 32 % for T. vivax (I2 = 60 %: P = 0.61) and 19 % for T. brucei (95 % CI: 7 %-41 %). Among the risk factors, poor body condition, black coat color, and packed cell volume (PCV) were found to be significant for the development of this disease. Black-coated animals were 2.36 and 3.48 times more susceptible to trypanosomosis than red- and white-coated animals, respectively. According to the pooled odds ratio, animals in poor body condition were 2.82 times more likely to have bovine trypanosomosis. Animals infected with Trypanosoma were 18 times more likely to have a lower packed cell volume (PCV) compared to non-infected animals. The study found that Tsetse flies were responsible for 72.32 % of bovine trypanosomosis cases, with Glossina pallidipes and Glossina tachinoides being the most common species. The remaining 27.68 % were due to other biting insects. The study highlights the need for science-based risk mitigation strategies to control Trypanosoma infections, emphasizing the crucial role of Tsetse flies, particularly G. pallidipes and G. tachinoides, in transmission.

    PMID:39525367 | PMC:PMC11546430 | DOI:10.1016/j.parepi.2024.e00388

  • In-Depth Development of a Versatile Rumen Bolus Sensor for Dairy Cattle

    Sensors (Basel). 2024 Oct 30;24(21):6976. doi: 10.3390/s24216976.

    ABSTRACT

    Precision agriculture and the increasing automation efforts in animal husbandry requires continuous and complex monitoring of the animals. Rumen bolus sensors, which are cutting-edge pieces of technology and a rapidly developing research field, present an exceptional opportunity for monitoring the health status, physiological parameters, and estrus of the animals. The objective of this paper is to provide a comprehensive overview of the development process of a new sensor development. We address the issues of conceptual design, an overview of applicable sensor modalities, mechanical design, power supply design, applicable hardware solutions, applicable communication solutions and finally the sensor detection algorithms proved in field tests. In conclusion, we present a summary of the current opportunities in the field and provide an analysis of the foreseeable trends.

    PMID:39517871 | PMC:PMC11548120 | DOI:10.3390/s24216976

  • Internet of Things (IoT): Sensors Application in Dairy Cattle Farming

    Animals (Basel). 2024 Oct 24;14(21):3071. doi: 10.3390/ani14213071.

    ABSTRACT

    The expansion of dairy cattle farms and the increase in herd size have made the control and management of animals more complex, with potentially negative effects on animal welfare, health, productive/reproductive performance and consequently farm income. Precision Livestock Farming (PLF) is based on the use of sensors to monitor individual animals in real time, enabling farmers to manage their herds more efficiently and optimise their performance. The integration of sensors and devices used in PLF with the Internet of Things (IoT) technologies (edge computing, cloud computing, and machine learning) creates a network of connected objects that improve the management of individual animals through data-driven decision-making processes. This paper illustrates the main PLF technologies used in the dairy cattle sector, highlighting how the integration of sensors and devices with IoT addresses the challenges of modern dairy cattle farming, leading to improved farm management.

    PMID:39518794 | PMC:PMC11545371 | DOI:10.3390/ani14213071