LncRNA BlncAD1 Modulates Bovine Adipogenesis by Binding to MYH10, PI3K/Akt Signaling Pathway, and miR-27a-5p/CDK6 Axis.

Research on adipogenesis will help to improve the meat quality of livestock. Long noncoding RNAs (lncRNAs) are involved in mammalian adipogenesis as epigenetic modulators. In this study, we analyzed lncRNA expression during bovine adipogenesis and detected 195 differentially expressed lncRNAs, including lncRNA BlncAD1, which was significantly upregulated in mature bovine adipocytes. Gain- and loss-of-function experiments confirmed that BlncAD1 promoted the proliferation, apoptosis, and differentiation of bovine preadipocytes. RNA pull-down revealed that the nonmuscle myosin 10 (MYH10) is a potential binding protein of BlncAD1. Then, we elucidated that loss of BlncAD1 caused increased ubiquitination of MYH10, which confirmed that BlncAD1 regulates adipogenesis by enhancing the stability of the MYH10 protein. Western blotting was used to demonstrate that BlncAD1 activated the PI3K/Akt signaling pathway. Bioinformatic analysis and dual-luciferase reporter assays indicated that BlncAD1 competitively absorbed miR-27a-5p. The overexpression and interference of miR-27a-5p in bovine preadipocytes displayed that miR-27a-5p inhibited proliferation, apoptosis, and differentiation. Further results suggested that miR-27a-5p targeted the CDK6 gene and that BlncAD1 controlled the proliferation of bovine preadipocytes by modulating the miR-27a-5p/CDK6 axis. This study revealed the complex mechanisms of BlncAD1 underlying bovine adipogenesis for the first time, which would provide useful information for genetics and breeding improvement of Chinese beef cattle.

The antiglycation potential of H1 receptor antagonists - in vitro studies in bovine serum albumin model and in silico molecular docking analyses.

The H1 receptor belongs to the family of rhodopsin-like G-protein-coupled receptors activated by the biogenic amine histamine. H1 receptor antagonists are widely used in the treatment of allergies. However, these drugs could have a much broader spectrum of activity, including hypoglycemic effects, which can broaden the spectrum of their use. The aim of the study was to evaluate the antiglycation potential of twelve H1 receptor antagonists (diphenhydramine, antazoline, promethazine, ketotifen, clemastine, pheniramine, cetirizine, levocetirizine, bilastine, fexofenadine, desloratadine, and loratadine). Bovine serum albumin (BSA) was glycated with sugars (glucose, fructose, galactose, and ribose) and aldehydes (glyoxal and methylglyoxal) in the presence of H1 blockers. The tested substances did not induce a significant decrease in the content of albumin glycation end-products, and the inhibition rate of glycoxidation was not influenced by the chemical structure or generation of H1 blockers. None of the tested H1 receptor antagonists exhibited strong antiglycation activity. Antiglycemic potential of H1 blockers could be attributed to their antioxidant and anti-inflammatory activity, as well as their effects on carbohydrate metabolism/metabolic balance at the systemic level.

Construction of diallyltrisulfide nanoparticles for alleviation of ethanol-induced acute gastric injury.

Gastric ulcer, a significant health issue characterized by the degradation of the gastric mucosa, often arises from excessive gastric acid secretion and poses a challenge in current medical treatments due to the limited efficacy and side effects of first-line drugs. Addressing this, our study develops a novel therapeutic strategy leveraging gas therapy, specifically targeting the release of hydrogen sulfide (H2S) in the treatment of gastric ulcers. We successfully developed a composite nanoparticle, named BSA·SH-DATS, through a two-step process. Initially, bovine serum albumin (BSA) was sulfhydrated to generate BSA·SH nanoparticles via a mercaptosylation method. Subsequently, these nanoparticles were further functionalized by incorporating diallyltrisulfide (DATS) through a precise Michael addition reaction. This sequential modification resulted in the creation of BSA·SH-DATS nanoparticles. Our comprehensive in vitro and in vivo investigations demonstrate that these nanoparticles possess an exceptional ability for site-specific action on gastric mucosal cells under the controlled release of H2S in response to endogenous glutathione (GSH), markedly diminishing the production of pro-inflammatory cytokines, thereby alleviating inflammation and apoptosis. Moreover, the BSA·SH-DATS nanoparticles effectively regulate critical inflammatory proteins, including NF-κB and Caspase-3. Our study underscores their potential as a transformative approach for gastric ulcer treatment.

Serological and epidemiological investigation of Mycobacterium avium subspecies paratuberculosis in bovines in Pakistan.

Objective: To investigate the prevalence of paratuberculosis in cattle and buffaloes at twelve public dairy farms in Punjab, Pakistan. Methods: A total of 2181 more than two-year-old animals (1242 cattle and 939 buffaloes) were tested by avian tuberculin, i.e., killed purified protein derivative (PPD) of Mycobacterium avium paratuberculosis and indirect ELISA. Blood and fecal samples were collected from tuberculin positive animals. These samples were further processed by indirect ELISA. The data were analyzed using frequency analysis and logistic analysis procedures. Results: The prevalence of paratuberculosis at public dairy farms was 3.8%, as determined by tuberculin + ELISA test. It varied from 0.71-13.5% with a 100% herd prevalence. Multivariate logistic regression analysis revealed that species, milk production, total animals, total small ruminants, and total buffaloes were significantly associated with the occurrence of paratuberculosis. Odd ratio analysis revealed that with a one-kilogram increase in body weight, there will be a 0.006% increase in disease occurrence. With the increase in one animal in small ruminants and buffaloes, there will be 0.008% and 0.42% greater chances of developing paratuberculosis, respectively. Bivariate logistic regression analysis of cattle and buffaloes revealed that farm number, age, and total number of cattle were significantly associated with the occurrence of paratuberculosis. A one-month increase in lactation length increases the chance of tuberculosis by 0.004%; similarly, a one-liter increase in milk production increases the chance of disease by 10%. With each additional buffalo in the herd, there will be a 0.007% greater chance for the occurrence of paratuberculosis. Conclusion: This study concluded that tuberculin testing can be used in conjunction with ELISA to screen animals for paratuberculosis in countries with scarce resources, such as Pakistan. The efficacy of disease diagnosis can be improved by combining multiple tests.

First evaluation of the impact of a targeted subunit vaccine against bovine viral diarrhea virus in feedlot cattle.

Bovine respiratory disease (BRD) is a serious health and economic problem in the beef industry, which is often associated with transportation and caused by different pathogens. In this study, we evaluated the effect of a novel subunit targeted vaccine against bovine viral diarrhea virus (BVDV) in feedlot cattle, a major viral agent of BRD. The core of this novel vaccine is the fusion of the BVDV structural glycoprotein, E2, to a single-chain antibody, APCH, together termed, APCH-E2. The APCH antibody targets the E2 antigen to the major histocompatibility type II molecule (MHC-II) present in antigen-presenting cells. To evaluate the vaccine, 2,992 animals were randomly allocated into two groups, control group (N = 1,491) and treatment group (N = 1,501). Animals of both groups received the routine sanitary plan: two doses of clostridial, respiratory, and rabies vaccines. Animals within the treatment group also received two doses of a targeted subunit vaccine against BVDV. Serum samples were taken on the day of the first inoculation (T0) and 90 d later (T90). Viral circulation was monitored using an anti-P80 ELISA (virus-specific) and immune response was evaluated by anti-E2 ELISA (detects virus and vaccine immune responses). Only animals treated for respiratory disease were considered positive cases of BRD. Results demonstrate that the control group had significantly more animals treated for BRD cases compared to the treatment group (5.9% vs. 3.7%, P = 0.02). The control group had a greater number of animals positive for anti-P80 antibodies and significantly fewer animals positive for anti-E2 antibodies compared to the treatment group (69% vs. 61% and 71% vs. 99%, respectively, P = 0.003), consistent with natural viral circulation within this group. The treatment group, conversely, had fewer animals positive for anti-P80 antibodies and a greater number of animals positive for anti-E2 antibodies, consistent with a robust vaccine-induced antibody response and a reduction of the BVDV circulation within this group. The data indicate the new subunit targeted vaccine induced greater anti-E2 antibodies and reduced the amount of BVD virus circulation within the treatment group leading to a fewer number of animals needing to be treated for BRD.

Slow pyrolysis of Terminalia catappa L. municipal solid waste and the use of the aqueous fraction produced for bovine mastitis control.

The Terminalia catappa L. tree is an ornamental and shade tree producter of a large amount of biological waste sent to landfills. Therefore, this plant constitutes so-called municipal solid wood waste (MSWW), which causes undesirable impacts on the environment, such as the generation of methane through the action of microorganisms. Sustainable solutions for the proper use and disposal of MSWW are a topic that has assumed great relevance at present due to the high quantities of MSWW generated worldwide. Pyrolysis constitutes an attractive alternative for the sustainable use of MSWW to produce higher value-added products. This study investigated the slow pyrolysis of Terminalia catappa L. fruit and the use of the aqueous fraction produced for bovine mastitis control. We obtained four fractions from the pyrolysis process, with average yields of the aqueous phase (36.22 ± 2.0 %), bio-oil (5.52 ± 0.4 %), biochar (37.55 ± 2.8 %) and gas (20.71 ± 2.0 %). The aqueous fraction was extracted with organic solvents and analyzed by gas chromatography coupled to mass spectrometry (GC‒MS). The extracts were composed mainly of phenols (50 %), furan derivatives, cyclic ketones, and others with lower contents, such as alcohols and esters. The aqueous fraction had bactericidal activity against Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, which are responsible for bovine mastitis. In addition, the fraction showed low cytotoxicity against a murine melanoma cell line from a C57BL/6J mouse, B16F10 cells and mouse peritoneal cells.

Administering the maternal appeasing substance before slaughter to improve carcass characteristics of finishing cattle.

Two experiments evaluated carcass characteristics of finishing steers administered the maternal bovine appeasing substance (mBAS) prior to slaughter. In Exp. 1, 954 Angus-influenced finishing steers housed in 6 original pens were used. Each original pen was split into a pair of experimental pens 14.3 d ±â€…3 d prior to slaughter, in a manner that number of steers and average pen body weight (BW; 636 ±â€…4 kg) were similar. An oiler containing mBAS (Ferappease Finish Cattle 5%; FERA Diagnostics and Biologicals; College Station, TX) was added to one of the experimental pens 7 d prior to slaughter (n = 6), whereas the other pen did not contain an oiler (CON; n = 6). The oiler delivered 120 mL of mBAS/steer during a 7-d period. Steer BW was recorded 7 d prior to and during loading (final BW) to the packing plant. No treatment effects were detected (P ≥ 0.51) for BW gain, final BW, and proportion of carcasses that graded Choice or Prime. Carcass dressing percentage was greater (P = 0.02) in mBAS compared with CON steers (65.9% vs. 64.2%; SEM = 0.5), which was not sufficient to impact hot carcass weight (HCW; P = 0.29). Incidence of dark-cutting carcasses did not differ between treatments (P = 0.23). In Exp. 2, 80 Angus-influenced finishing steers housed in 16 pens (5 steers/pen; 600 ±â€…4 kg of BW) were used. Pens were arranged in 4 rows of 4 pens/row, and rows were alternately assigned to receive an oiler containing mBAS (n = 8) or mineral oil (CON+; n = 8) 7 d prior to slaughter. Oilers were designed to deliver 120 mL/steer of mBAS or mineral oil during the 7-d period. Steer BW was recorded as in Exp. 1, and a blood sample was collected during exsanguination. No treatment effects were detected (P ≥ 0.20) for BW parameters, carcass marbling score, backfat thickness, Longissimus muscle area, yield grade, and proportion of carcasses that graded Choice or Prime. Carcass dressing was greater (P = 0.02) in mBAS steers compared with CON + (60.6 vs. 59.6%; SEM = 0.3) but HCW did not differ (P = 0.47) between treatments. Plasma cortisol concentration was less (P < 0.01) in mBAS steers compared with CON + (11.7 vs. 20.8 ng/mL; SEM = 1.6). Incidence of dark-cutting carcasses did not differ (P = 0.53) between treatments. In summary, mBAS administration to finishing cattle using oilers during the last 7 d on feed alleviated the adrenocortical stress response elicited by the process of slaughter, which likely resulted in increased carcass dressing.

Stability and integrity of self-assembled bovine parvovirus virus­like particles (BPV­VLPs) of VP2 and combination of VP1VP2 assisted by baculovirus-insect cell expression: a potential logistical platform for vaccine deployment.

BACKGROUND: Bovine parvovirus (BPV) is an autonomous DNA virus with a smaller molecular size and subtle differences in its structural proteins, unlike other animal parvoviruses. More importantly, this virus has the potential to produce visible to silent economic catastrophes in the livestock business, despite receiving very little attention. Parvoviral virus-like particles (VLPs) as vaccines and as logistical platforms for vaccine deployment are well studied. However, no single experimental report on the role of VP1 in the assembly and stability of BPV-VLPs is available. Furthermore, the self-assembly, integrity and stability of the VLPs of recombinant BPV VP2 in comparison to VP1 VP2 Cap proteins using any expression method has not been studied previously. In this study, we experimentally evaluated the self-assembling ability with which BPV virus-like particles (VLPs) could be synthesized from a single structural protein (VP2) and by integrating both VP2 and VP1 amino acid sequences. METHODS: In silico and experimental cloning methods were carried out. His-tagged and without-His-tag VP2 and V1VP2-encoding amino acid sequences were cloned and inserted into pFastbacdual, and insect cell-generated recombinant protein was evaluated by SDS‒PAGE and western blot. Period of infectivity and expression level were determined by IFA. The integrity and stability of the BPV VLPs were evaluated by transmission electron microscopy. The secondary structure of the BPV VLPs from both VP2 and V1VP2 was analyzed by circular dichroism. RESULTS: Our findings show that VP2 alone was equally expressed and purified into detectable proteins, and the stability at different temperatures and pH values was not appreciably different between the two kinds of VLPs. Furthermore, BPV-VP2 VLPs were praised for their greater purity and integrity than BPV-VP1VP2 VLPs, as indicated by SDS‒PAGE. Therefore, our research demonstrates that the function of VP1 has no bearing on the stability or integrity of BPV-VLPs. CONCLUSIONS: In summary, incredible physiochemically stable BPV VP2-derived VLPs have been found to be promising candidates for the development of multivalent vaccines and immunodiagnostic kits against enteric viruses and to carry heterogeneous epitopes for various economically important livestock diseases.

Advanced Tandem Mass Spectrometric Analysis of Complex Mixtures of Triacylglycerol Regioisomers: A Case Study of Bovine Milk Fat.

Comprehensive analysis of triacylglycerol (TAG) regioisomers is extremely challenging, with many variables that can influence the results. Previously, we reported a novel algorithmic method for resolving regioisomers of complex mixtures of TAGs. In the current study, the TAG Analyzer software and its mass spectrometric fragmentation model were further developed and validated for a much wider range of TAGs. To demonstrate the method, we performed for the first time a comprehensive analysis of TAG regioisomers of bovine milk fat, a very important and one of the most complex TAG mixtures in nature containing FAs ranging from short to long carbon chains. This analysis method forms a solid basis for further investigation of TAG regioisomer profiles in various natural fats and oils, potentially aiding in the development of new and healthier foods and nutraceuticals with targeted lipid structures.

Design of a multi-epitope-based vaccine candidate against Bovine Genital Campylobacteriosis using a reverse vaccinology approach.

BACKGROUND: Bovine Genital Campylobacteriosis (BGC), a worldwide distributed venereal disease caused by Campylobacter fetus subsp. venerealis (Cfv), has a relevant negative economic impact in cattle herds. The control of BGC is hampered by the inexistence of globally available effective vaccines. The present in silico study aimed to develop a multi-epitope vaccine candidate against Cfv through reverse vaccinology. RESULTS: The analysis of Cfv strain NCTC 10354 proteome allowed the identification of 9 proteins suitable for vaccine development. From these, an outer membrane protein, OmpA, and a flagellar protein, FliK, were selected for prediction of B-cell and T-cell epitopes. The top-ranked epitopes conservancy was assessed in 31 Cfv strains. The selected epitopes were integrated to form a multi-epitope fragment of 241 amino acids, which included 2 epitopes from OmpA and 13 epitopes from FliK linked by GPGPG linkers and connected to the cholera toxin subunit B by an EAAAK linker. The vaccine candidate was predicted to be antigenic, non-toxic, non-allergenic, and soluble upon overexpression. The protein structure was predicted and optimized, and the sequence was successfully cloned in silico into a plasmid vector. Additionally, immunological simulations demonstrated the vaccine candidate's ability to stimulate an immune response. CONCLUSIONS: This study developed a novel vaccine candidate suitable for further in vitro and in vivo experimental validation, which may become a useful tool for the control of BGC.

Slow freezing cryopreservation of Korean bovine blastocysts with an additional sucrose pre-equilibration step.

Introduction: Embryo cryopreservation is a valuable technique used for preserving genetic resources for long periods. However, the survival rate of embryos is dependent on the method used. Therefore, in this study, we evaluated the efficiency of slow freezing method but with an additional dehydration step prior to freezing to overcome the formation of ice crystals. Methods: Oocytes collected from the ovaries of native Korean cattle subjected to in vitro fertilization were cultured for 7 days until the formation of expanded blastocysts. Before freezing, the blastocysts were placed in four pre-equilibration media: a control medium with no addition of sucrose, and three experimental media with the addition of 0.1, 0.25, and 0.5 M sucrose, respectively. Then, the pre-equilibrated embryos were frozen. Embryo survival and hatching rates were evaluated morphologically at 24, 48, and 72 h after thawing. Immunofluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and gene expression analysis of the re-expanded blastocytes were examined 24 h after freeze-thawing. Results: The survival rate was significantly higher in the 0.1 M group than in the control group (p < 0.05), and the hatching rate at 72 h was significantly higher in the 0.25 and 0.5 M groups than in the control group (p < 0.05). TUNEL-positive cells were significantly lower in the 0.25 M group than in the control group (12.5 ± 0.9 vs. 8.3 ± 0.8; p < 0.05). The gene expression of BCL2 associated X, heat shock protein 70 kDa, and aquaporin 3 in the 0.25 M group was significantly lower than that in the control group (p < 0.05). Conclusion: Our study revealed that treatment with 0.25 M sucrose before slow freezing improved the viability of bovine embryos after freeze-thawing.

Screening of mRNA markers in early bovine tuberculosis blood samples.

Bovine tuberculosis (bTB) is a chronic zoonotic disease caused by Mycobacterium bovis. A large number of cattle are infected with bTB every year, resulting in huge economic losses. How to control bTB is an important issue in the current global livestock economy. In this study, the original transcriptome sequences related to this study were obtained from the dataset GSE192537 by searching the Gene Expression Omnibus (GEO) database. Our differential gene analysis showed that there were obvious biological activities related to immune activation and immune regulation in the early stage of bTB. Immune-related biological processes were more active in the early stage of bTB than in the late. There were obvious immune activation and immune cell recruitment in the early stage of bTB. Regulations in immune receptors are associated with pathophysiological processes of the early stage of bTB. A gene module consisting of 236 genes significantly related to the early stage of bTB was obtained by weighted gene co-expression network analysis, and 18 hub genes were further identified as potential biomarkers or therapeutic targets. Finally, by random forest algorithm and logistic regression modeling, FCRL1 was identified as a representative mRNA marker in early bTB blood. FCRL1 has the potential to be a diagnostic biomarker in early bTB.

Diagnosis of bovine viral diarrhea virus: an overview of currently available methods.

Bovine viral diarrhea virus (BVDV) is the causative agent of bovine viral diarrhea (BVD), which results in significant economic losses in the global cattle industry. Fortunately, various diagnostic methods available for BVDV have been established. They include etiological methods, such as virus isolation (VI); serological methods, such as enzyme-linked immunosorbent assay (ELISA), immunofluorescence assay (IFA), and immunohistochemistry (IHC); molecular methods, such as reverse transcription-polymerase chain reaction (RT-PCR), real-time PCR, digital droplet PCR (ddPCR), loop-mediated isothermal amplification (LAMP), recombinase polymerase amplification (RPA), and CRISPR-Cas system; and biosensors. This review summarizes the current diagnostic methods for BVDV, discussing their advantages and disadvantages, and proposes future perspectives for the diagnosis of BVDV, with the intention of providing valuable guidance for effective diagnosis and control of BVD disease.

Modulation of Apoptosis by Bovine Gammaherpesvirus 4 Infection in Bovine Endometrial Cells and the Possible Role of LPS in This Process.

The prevalent pathogens associated with bovine uterine infections are bacteria that appear to increase the host's susceptibility to secondary infections with other bacteria or viruses, among which BoGHV4 is the most frequently found. In this work, the study of the pathways of apoptosis induction was carried out on an experimental model of primary culture of endometrial cells, in order to know the implication of BoGHV4 and the presence of bacterial LPS in the pathogenesis of the bovine reproductive tract. For this, different staining techniques and molecular analysis by RT-PCR were used. The results obtained allowed us to conclude that the level of cell death observed in the proposed primary culture is directly related to the time of viral infection and the presence of LPS in BoGHV4 infection. The apoptosis indices in cells infected with BoGHV4 and BoGHV4 + LPS revealed a maximum that correlated with the appearance of cytopathic effects and the maximum viral titers in the model studied. However, morphological, biochemical, and molecular changes were evident during both early and late stages of apoptosis. These findings provide information on the factors that may influence the pathogenesis of BoGHV4 and help to better understand the mechanisms involved in virus infection.

Variation in Pen-Level Prevalence of BRD Bacterial Pathogens and Antimicrobial Resistance Following Feedlot Arrival in Beef Calves.

Antimicrobials are crucial for treating bovine respiratory disease (BRD) in beef feedlots. Evidence is needed to support antimicrobial use (AMU) decisions, particularly in the early part of the feeding period when BRD risk is highest. The study objective was to describe changes in prevalence and antimicrobial susceptibility of BRD bacterial pathogens at feedlot processing (1 day on feed (1DOF)), 12 days later (13DOF), and for a subset at 36DOF following metaphylactic antimicrobial treatment. Mixed-origin steer calves (n = 1599) from Western Canada were managed as 16 pens of 100 calves, receiving either tulathromycin (n = 1199) or oxytetracycline (n = 400) at arrival. Deep nasopharyngeal swabs collected at all time points underwent culture and antimicrobial susceptibility testing (AST). Variability in the pen-level prevalence of bacteria and antimicrobial susceptibility profiles were observed over time, between years, and metaphylaxis options. Susceptibility to most antimicrobials was high, but resistance increased from 1DOF to 13DOF, especially for tetracyclines and macrolides. Simulation results suggested that sampling 20 to 30 calves per pen of 200 reflected the relative pen-level prevalence of the culture and AST outcomes of interest. Pen-level assessment of antimicrobial resistance early in the feeding period can inform the evaluation of AMU protocols and surveillance efforts and support antimicrobial stewardship in animal agriculture.

Exploring Anti-Fibrotic Effects of Adipose-Derived Stem Cells: Transcriptome Analysis upon Fibrotic, Inflammatory, and Hypoxic Conditioning.

Autologous fat transfers show promise in treating fibrotic skin diseases, reversing scarring and stiffness, and improving quality of life. Adipose-derived stem cells (ADSCs) within these grafts are believed to be crucial for this effect, particularly their secreted factors, though the specific mechanisms remain unclear. This study investigates transcriptomic changes in ADSCs after in vitro fibrotic, inflammatory, and hypoxic conditioning. High-throughput gene expression assays were conducted on ADSCs exposed to IL1-ß, TGF-ß1, and hypoxia and in media with fetal bovine serum (FBS). Flow cytometry characterized the ADSCs. RNA-Seq analysis revealed distinct gene expression patterns between the conditions. FBS upregulated pathways were related to the cell cycle, replication, wound healing, and ossification. IL1-ß induced immunomodulatory pathways, including granulocyte chemotaxis and cytokine production. TGF-ß1 treatment upregulated wound healing and muscle tissue development pathways. Hypoxia led to the downregulation of mitochondria and cellular activity.

Antimicrobial Resistance Genes in Respiratory Bacteria from Weaned Dairy Heifers.

Bovine respiratory disease (BRD) is the leading cause of mortality and antimicrobial drug (AMD) use in weaned dairy heifers. Limited information is available regarding antimicrobial resistance (AMR) in respiratory bacteria in this population. This study determined AMR gene presence in 326 respiratory isolates (Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni) from weaned dairy heifers using whole genome sequencing. Concordance between AMR genotype and phenotype was determined. Twenty-six AMR genes for 8 broad classes of AMD were identified. The most prevalent, medically important AMD classes used in calf rearing, to which these genes predict AMR among study isolates were tetracycline (95%), aminoglycoside (94%), sulfonamide (94%), beta-lactam (77%), phenicol (50%), and macrolide (44%). The co-occurrence of AMR genes within an isolate was common; the largest cluster of gene co-occurrence encodes AMR to phenicol, macrolide, elfamycin, ß-lactam (cephalosporin, penam cephamycin), aminoglycoside, tetracycline, and sulfonamide class AMD. Concordance between genotype and phenotype varied (Matthew's Correlation Coefficient ranged from -0.57 to 1) by bacterial species, gene, and AMD tested, and was particularly poor for fluoroquinolones (no AMR genes detected) and ceftiofur (no phenotypic AMR classified while AMR genes present). These findings suggest a high genetic potential for AMR in weaned dairy heifers; preventing BRD and decreasing AMD reliance may be important in this population.

Molecular Characterisation and Antibody Response to Bovine Respiratory Syncytial Virus in Vaccinated and Infected Cattle in Turkey.

Bovine respiratory syncytial virus (BRSV) is one of the most important respiratory pathogens of cattle. In this study, frequency of infection, analysis of variants, and the immune status of vaccinated and non-vaccinated cattle were studied. Blood (n = 162) and nasal/oropharyngeal (n = 277) swabs were collected from 62 cattle herds in Turkey. Lung samples (n = 37) were also taken from dead animals and abattoirs. Antibodies to BRSV were detected in 76 (46%) out of 162 sera. The antibody levels in the vaccinated and non-vaccinated groups were statistically significant. Among 277 nasal/oropharyngeal swabs and 37 lungs, ten nasal/oropharyngeal and four lung samples were positive for BRSV-RNA. BRSV-G gene sequences of 5 out of 14 RT-PCR positive samples showed that all viruses clustered as Group-III in phylogenetic analysis with 88-100% homology. Similarity with previous Turkish BRSVs was 89-98%, and that with BRSVs detected in the USA and Czechia was 89.47-93.12%. BRSV continues to circulate in Turkish cattle, and vaccination seems beneficial in preventing BRSV. The diversity of the BRSVs found in this study needs be considered in vaccination strategies.

Cathepsin S Is More Abundant in Serum of Mycobacterium avium subsp. paratuberculosis-Infected Dairy Cows.

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of bovine paratuberculosis, a chronic granulomatous enteritis leading to economic losses and posing a risk to human health due to its zoonotic potential. The pathogen cannot reliably be detected by standard methods, and immunological procedures during the infection are not well understood. Therefore, the aim of our study was to explore host-pathogen interactions in MAP-infected dairy cows and to improve diagnostic tests. Serum proteomics analysis using quantitative label-free LC-MS/MS revealed 60 differentially abundant proteins in MAP-infected dairy cows compared to healthy controls from the same infected herd and 90 differentially abundant proteins in comparison to another control group from an uninfected herd. Pathway enrichment analysis provided new insights into the immune response to MAP and susceptibility to the infection. Furthermore, we found a higher abundance of Cathepsin S (CTSS) in the serum of MAP-infected dairy cows, which is involved in multiple enriched pathways associated with the immune system. Confirmed with Western blotting, we identified CTSS as a potential biomarker for bovine paratuberculosis. This study enabled a better understanding of procedures in the host-pathogen response to MAP and improved detection of paratuberculosis-diseased cattle.

Biofilm Formation and Antimicrobial Resistance of Staphylococcus aureus and Streptococcus uberis Isolates from Bovine Mastitis.

This study aimed to assess (a) the biofilm producer ability and antimicrobial resistance profiles of Staphylococcus (Staph.) aureus and Streptococcus (Strep.) uberis isolated from cows with clinical mastitis (CM) and subclinical mastitis (SCM), and (b) the association between biofilm producer ability and antimicrobial resistance. We isolated a total of 197 Staph. aureus strains (SCM = 111, CM = 86) and 119 Strep. uberis strains (SCM = 15, CM = 104) from milk samples obtained from 316 cows distributed in 24 dairy herds. Biofilm-forming ability was assessed using the microplate method, while antimicrobial susceptibility was determined using the disk diffusion method against 13 antimicrobials. Among the isolates examined, 57.3% of Staph. aureus and 53.8% of Strep. uberis exhibited the ability to produce biofilm, which was categorized as strong, moderate, or weak. In terms of antimicrobial susceptibility, Staph. aureus isolates displayed resistance to penicillin (92.9%), ampicillin (50.8%), and tetracycline (52.7%). Conversely, Strep. uberis isolates exhibited resistance to penicillin (80.6%), oxacillin (80.6%), and tetracycline (37.8%). However, no significant correlation was found between antimicrobial resistance patterns and biofilm formation ability among the isolates.