Search Results (4,041)

Background/Objectives: The emergence of the mobilized colistin resistance 1 (mcr-1) gene, which causes colistin resistance, is a serious concern in animal husbandry, particularly in pigs. Although antibiotic regulations in many countries have prohibited the use of colistin in livestock, the persistence and dissemination of this plasmid-mediated gene require effective and rapid monitoring. Therefore, a rapid, sensitive, and specific method combining recombinase polymerase amplification (RPA) with an in-house lateral flow assay (LFA) for the mcr-1 gene detection was developed. Methods: The colistin agar test and broth microdilution were employed to screen 152 E. coli isolates from pig fecal samples of five antibiotic-used farms. The established RPA-in-house LFA was validated with PCR for mcr-1 gene detection. Results: The RPA-in-house LFA was completed within 35 min (20 min of amplification and 5–15 min on LFA detection) at 37 °C. The sensitivity, specificity, and accuracy were entirely 100% in concordance with PCR results. No cross-reactivity was detected with seven common pathogenic bacteria or other mcr gene variants. Conclusions: Therefore, the in-house RPA-LFA serves as a point-of-care testing tool that is rapid, simple, and portable, facilitating effective surveillance of colistin resistance in both veterinary and clinical settings, thereby enhancing health outcomes. Full article

Outbreaks of furunculosis cause significant losses in salmonid aquaculture worldwide. With a recent rise in antimicrobial resistance, regulatory measures to minimize the use of antibiotics in animal husbandry, including aquaculture, have increased scrutiny and availability of veterinary medical products to control this disease in production facilities. In such a regulatory environment, the utility of autogenous vaccines to assist with disease prevention and control as a veterinary-guided prophylactic measure is of high interest to the producers and veterinary services alike. However, evolving concepts of epidemiological units and epidemiological links need to be considered during approval and acceptance procedures for the application of autogenous vaccines in multiple aquaculture facilities. Here, we present the results of solid-state nanopore sequencing (Oxford Nanopore Technologies, ONT) performed on 54 isolates of Aeromonas salmonicida ssp. salmonicida sampled during clinical outbreaks of furunculosis in different aquaculture facilities from Bavaria, Germany, from 2017 to 2020. All of the performed analyses (phylogeny, single nucleotide polymorphism and 3D protein modeling for major immunogenic proteins) support a high probability that all studied isolates belong to the same epidemiological unit. Simultaneously, we describe a cost/effective method of whole genome analysis with the usage of ONT as a viable strategy to study outbreaks of other pathogens in the field of aquatic veterinary medicine for the purpose of developing the best autogenous vaccine candidates applicable to multiple aquaculture establishments. Full article

Background/Objectives: The current Bordetella bronchiseptica (Bb) vaccine, when adjuvanted with alum, does not elicit adequate robust cellular immunity or effective antibody defense against Bb attacks. Unfortunately, antibiotic treatment generally represents an ineffective strategy due to the development of resistance against a broad range of antibiotics. Methods: The present study was designed to investigate the immune response, protective capabilities and underlying mechanisms of a plant oil-based adjuvant E515 formulated with inactivated Bb antigen as a potential vaccine candidate against Bordetella bronchiseptica. Results: Immunization studies revealed that a combination of SO, VE and GS (E515) exhibited a good synergistic adjuvant effect. The E515 adjuvanted Bb vaccine was proven to be highly efficacious and induced a mixed Th1/Th2/Th17 immune response in mice, leading to a significant increase in Bb-specific IgG, IgG1 and IgG2a antibodies, proliferative lymphocyte responses and cytokine levels (by lymphocytes and serum) and effectively induced responses by CD4⁺ TE, TM cells and B cells. The E515 adjuvant significantly enhanced the immune protection provided by the Bb vaccine in a mice model, as indicated by a reduced bacterial burden in the lungs. Multi-omics sequencing analysis revealed that E515 functions as an adjuvant by modulating critical pathways, including cytokine–cytokine receptor interaction, the IL-17 signaling pathway and the chemokine signaling pathway. This modulation also included interactions with beneficial species of bacteria including Alistipes, Odoribacter and Colidextribacter, as well as energy and lipid-related metabolites, thus highlighting its role as an immunomodulatory agent. Conclusion: Collectively, our results demonstrate the huge potential of E515-Bb vaccine candidates, thus highlighting the vegetable oil original adjuvant E515 as a promising agent for the development of new veterinary vaccines. Full article

The swnH1 gene in the endophytic fungus Alternaria oxytropis OW 7.8 isolated from Oxytropis glabra was identified, and the gene knockout mutant ΔswnH1 was first constructed in this study. Compared with A. oxytropis OW 7.8, the ΔswnH1 mutant exhibited altered colony and mycelium morphology, slower growth rate, and no swainsonine (SW) in mycelia, indicating that the function of the swnH1 gene promoted SW biosynthesis. Five differential expressed genes (DEGs) closely associated with SW synthesis were identified by transcriptomic analysis of A. oxytropis OW 7.8 and ΔswnH1, with sac, swnR, swnK, swnN, and swnH2 down-regulating. Six differential metabolites (DEMs) closely associated with SW synthesis were identified by metabolomic analysis, with P450, PKS-NRPS, saccharopine, lipopolysaccharide kinase, L-PA, α-aminoadipic, and L-stachydrine down-regulated, while L-proline was up-regulated. The SW biosynthetic pathways in A. oxytropis OW 7.8 were predicted and refined. The results lay the foundation for in-depth exploration of the molecular mechanisms and metabolic pathways of SW synthesis in fungi and provide reference for future control of SW in locoweeds, which would benefit the development of animal husbandry and the sustainable use of grassland ecosystems. Full article

In modern animal husbandry, increasing attention is given to mathematical modeling and statistical methods, especially for evaluating commercial hybrids. Our aim was to evaluate the phenotypic and genetic variability of biochemical parameters of blood serum of the 56 hybrid boars (Large White × Landrace × Duroc) raised in feeding stations (Russia) through mathematical modeling. The particular variances and covariances of traits were calculated using the limited maximum likelihood model and the REMLF90 programs. A narrow range of variability was found for major biochemical parameters in relationship with the “FFG-factor” (“fattening period × final live weight × gain”), including the majority of the metabolites (p ≤ 0.05). The highest values of the genetic correlations were observed for the “total protein” parameter with albumins (0.78), globulins (0.94), creatinine (0.99), and enzymes: AST (0.98), ALT (0.80), etc. Phenotypic and genetic relationships showed fairly high correlation coefficients (0.5–0.8). It is important to emphasize that most of the studied amino acids (alanine, arginine, aspartic acid and asparagine, glutamic acid and glutamine, glycine, isoleucine, leucine, serine, threonine, tyrosine, valine) were significantly associated with the “FFG-factor” (p ≤ 0.05). The proposed approach provides reliable data on metabolite variability and correlations. Full article

As an important ecological barrier and a crucial base for animal husbandry in China, the forage–livestock balance in the Three-River-Source Region (TRSR) directly impacts both the degradation and recovery of grassland. This study examines the forage–livestock balance in the TRSR over the past 13 years (2010–2022) by calculating both the theoretical and actual livestock carrying capacity, thereby providing a scientific basis for regional animal husbandry policies. Firstly, the Carnegie–Ames–Stanford Approach (CASA) model was improved to fit the specific characteristics of alpine grassland ecosystem in the TRSR. This enhanced model was subsequently used to calculate the net primary productivity (NPP) of the grassland, from which the regional grassland yield and theoretical livestock carrying capacity were derived. Secondly, the actual livestock carrying capacity was calculated and spatialized based on the number of regional year-end livestock. Finally, the livestock carrying pressure index was determined using both the theoretical and actual livestock carrying capacity. The results revealed several key findings: (1) The average grassland NPP in the TRSR was 145.44 gC/m², the average grassland yield was 922.7 kg/hm², and the average theoretical livestock carrying capacity was 0.55 SU/hm² from 2010 to 2022. Notably, all three metrics showed an increasing trend over the past 13 years, which indicates the rise in grassland vegetation activities. (2) The average actual livestock carrying capacity over the 13-year period was 0.46 SU/hm², showing a decreasing trend on the whole. The spatial distribution displayed a pattern of higher capacity in the east and lower in the west. (3) Throughout the 13 years, the TRSR generally maintained a forage–livestock balance, with an average livestock carrying pressure index of 0.96 (insufficient). However, the trend of livestock carrying pressure is on the rise, with serious overloading observed in the western part of Qumalai County and the northern part of Tongde County. Slight overloading was also noted in Zhiduo, Maduo, and Zeku Counties. Notably, Tanggulashan Town, Zhiduo, Qumalai, and Maduo Counties showed significant increases in livestock carrying pressure, while Zaduo County and the eastern regions experienced significant decreases. In conclusion, this study not only provides feasible technical methods for assessing and managing the forage–livestock balance in the TRSR but also contributes significantly to the sustainable development of the region’s grassland ecosystem and animal husbandry industry. Full article

In smart ranch management, cattle behavior recognition and tracking play a crucial role in evaluating animal welfare. To address the issues of missed and false detections caused by inter-cow occlusions and infrastructure obstructions in the barn environment, this paper proposes a multi-object tracking method called YOLO-BoT. Built upon YOLOv8, the method first integrates dynamic convolution (DyConv) to enable adaptive weight adjustments, enhancing detection accuracy in complex environments. The C2f-iRMB structure is then employed to improve feature extraction efficiency, ensuring the capture of essential features even under occlusions or lighting variations. Additionally, the Adown downsampling module is incorporated to strengthen multi-scale information fusion, and a dynamic head (DyHead) is used to improve the robustness of detection boxes, ensuring precise identification of rapidly changing target positions. To further enhance tracking performance, DIoU distance calculation, confidence-based bounding box reclassification, and a virtual trajectory update mechanism are introduced, ensuring accurate matching under occlusion and minimizing identity switches. Experimental results demonstrate that YOLO-BoT achieves a mean average precision (mAP) of 91.7% in cattle detection, with precision and recall increased by 4.4% and 1%, respectively. Moreover, the proposed method improves higher order tracking accuracy (HOTA), multi-object tracking accuracy (MOTA), multi-object tracking precision (MOTP), and IDF1 by 4.4%, 7%, 1.7%, and 4.3%, respectively, while reducing the identity switch rate (IDS) by 30.9%. The tracker operates in real-time at an average speed of 31.2 fps, significantly enhancing multi-object tracking performance in complex scenarios and providing strong support for long-term behavior analysis and contactless automated monitoring. Full article

Background/Objectives: Vaccines may improve the control and eradication of bovine tuberculosis. However, the evaluation of experimental candidates requires the assessment of the protection, excretion, transmission and biosafety. A natural transmission trial among likely infected animals was conducted. Methods: Seventy-four male heifers were randomly distributed (five groups) and vaccinated subcutaneously with attenuated strains (M. bovis Δmce2 or M. bovis Δmce2-phoP), a recombinant M. bovis BCG Pasteur (BCGr) or M. bovis BCG Pasteur. Then, they cohoused with a naturally infected bTB cohort under field conditions exposed to the infection. Results: A 23% of transmission of wild-type strains was confirmed (non-vaccinated group). Strikingly, first vaccination did not induce immune response (caudal fold test and IFN-gamma release assay). However, after 74 days of exposure to bTB, animals were re-vaccinated. Although their sensitization increased throughout the trial, the vaccines did not confer significant protection, when compared to the non-vaccinated group, as demonstrated by pathology progression of lesions and confirmatory tools. Besides, the likelihood of acquiring the infection was similar in all groups compared to the non-vaccinated group (p > 0.076). Respiratory and digestive excretion of viable vaccine candidates was undetectable. To note, the group vaccinated with M. bovis Δmce2-phoP exhibited the highest proportion of animals without macroscopic lesions, compared to the one vaccinated with BCG, although this was not statistically supported. Conclusions: This highlights that further evaluation of these vaccines would not guarantee better protection. The limitations detected during the trial are discussed regarding the transmission rate of M. bovis wild-type, the imperfect test for studying sensitization, the need for a DIVA diagnosis and management conditions of the trials performed under routine husbandry conditions. Re-vaccination of likely infected bovines did not highlight a conclusive result, even suggesting a detrimental effect on those vaccinated with M. bovis BCG. Full article

Heavy metal contamination in agricultural soils presents serious environmental and health risks. This study assessed the bioaccumulation and spatial distribution of nickel, cadmium, zinc, lead, and copper within a sheep-based food chain in the Baia Mare region, Romania, which includes soil, green grass, sheep serum, and dairy products. Using inductively coupled plasma mass spectrometry (ICP-MS), we analyzed the concentrations of these metals and calculated bioconcentration factors (BCFs) to evaluate their transfer through trophic levels. Spatial analysis revealed that copper (up to 2528.20 mg/kg) and zinc (up to 1821.40 mg/kg) exceeded permissible limits, particularly near former mining sites. Elevated lead (807.59 mg/kg) and cadmium (2.94 mg/kg) were observed in industrial areas, while nickel and cobalt showed lower concentrations, but with localized peaks. Zinc was the most abundant metal in grass, while cadmium transferred efficiently to milk and cheese, raising potential health concerns. The results underscore the complex interplay between soil properties, contamination sources, and biological processes in heavy metal accumulation. These findings highlight the importance of continuous monitoring, risk assessment, and mitigation strategies to protect public health from potential exposure through contaminated dairy products. Full article

Continuous movement monitoring helps quickly identify pig abnormalities, enabling immediate action to enhance pig welfare. However, continuous and precise monitoring of daily pig movement on farms remains challenging. We present an approach to automatically and precisely monitor the movement of group-housed pigs. The instance segmentation model YOLOv8m-seg was applied to detect the presence of pigs. We then applied a spatial moment algorithm to quantitatively summarize each detected pig’s contour as a corresponding center point. The agglomerative clustering (AC) algorithm was subsequently used to gather the pig center points of a single frame into one point representing the group-housed pigs’ position, and the movement volume was obtained by calculating the displacements of the clustered group-housed pigs’ center points of consecutive frames. We employed the method to monitor the movement of group-housed pigs from April to July 2023; more than 1500 h of top-down pig videos were recorded by a surveillance camera. The F1 scores of the trained YOLOv8m-seg model during training were greater than 90% across most confidence levels, and the model achieved an mAP50-95 of 0.96. The AC algorithm performs with an average extraction time of less than 1 millisecond; this method can run efficiently on commodity hardware. Full article

The Qinghai–Tibet Plateau (QTP) wild boar is an excellent model for investigating high-altitude adaptation. In this study, we analyzed genome-wide data from 93 wild boars compiled from various studies worldwide, including the QTP, southern and northern regions of China, Europe, Northeast Asia, and Southeast Asia, to explore their phylogenetic patterns and high-altitude adaptation based on genome-wide selection signal analysis and run of homozygosity (ROH) estimation. The findings demonstrate the alignment between the phylogenetic associations among wild boars and their geographical location. An ADMIXTURE analysis indicated a relatively close genetic relationship between QTP and southern Chinese wild boars. Analyses of the fixation index and cross-population extended haplotype homozygosity between populations revealed 295 candidate genes (CDGs) associated with high-altitude adaptation, such as TSC2, TELO2, SLC5A1, and SLC5A4. These CDGs were significantly overrepresented in pathways such as the mammalian target of rapamycin signaling and Fanconi anemia pathways. In addition, 39 ROH islands and numerous selective CDGs (e.g., SLC5A1, SLC5A4, and VCP), which are implicated in glucose metabolism and mitochondrial function, were discovered in QTP wild boars. This study not only assessed the phylogenetic history of QTP wild boars but also advanced our comprehension of the genetic mechanisms underlying the adaptation of wild boars to high altitudes. Full article

The aim of this study was to investigate the effects of Lentilactobacillus plantarum (LP), cellulase (CE), and xylanase (XE) supplementation on the fermentation quality, chemical composition, and bacterial community of Caragana korshinskii Kom. silage. Four groups were designed for the study. No additives were used in the control group (CK), and LP (1 × 10⁶ cfu/g), CE (1 × 10⁴ IU/g) and XE (2 × 10⁵ IU/g) were added to the experimental groups on a fresh matter basis, with three replicates per group. To promote fermentation, 5% molasses was added to all of the groups. On days 15 and 60, fermentation quality, chemical composition and the bacterial community were analysed. The pH of groups CE and XE was lower than that of the CK group at 60 days. During ensiling, the lactic acid (LA) content in the experimental groups and the acetic acid (AA) content in the CK and LP groups increased. At 60 days, the dominant genera in the CK and LP groups was Weissella and the dominant genera in the CE and XE groups was Lentilactobacillus. At different times during silage, nucleotide metabolism was enhanced, whereas the metabolism of carbohydrate, amino acids, energy, cofactors and vitamins was inhibited in the LP group. However, the metabolism of amino acids, energy, cofactors and vitamins in the CE and XE groups was increased, whereas the metabolism of nucleotides was inhibited. In conclusion, LP, CE and XE could exert a positive effect on the fermentation quality of C. korshinskii Kom. silage by shifting the bacterial community composition. Full article

The worrying issue of antibiotic resistance in pathogenic bacteria is aggravated by the scarcity of novel therapeutic agents. Antibiotic adjuvants offer a promising solution due to their cost-effectiveness and high efficacy in addressing this issue, such as the β-lactamase inhibitor sulbactam (a β-lactam adjuvant) and the dihydrofolate reductase inhibitor trimethoprim (a sulfonamide adjuvant). This study aimed to discover potential adjuvants for tetracyclines from a list of previously approved drugs to restore susceptibility to Escherichia coli carrying the tetA gene. We have screened guanethidine, a compound from the Chinese pharmacopoeia, which effectively potentiates the activity of tetracyclines by reversing resistance in tetA-positive Escherichia coli, enhancing its antibacterial potency, and retarding the development of resistance. Guanethidine functions via the inhibition of the TetA efflux pump, thereby increasing the intracellular concentration of tetracyclines. Our findings suggest that guanethidine holds promise as an antibiotic adjuvant. Full article

Immunosuppression undermines intestinal barrier integrity. Cow placenta extract (CPE) primarily consists of active peptides with immunomodulatory and antioxidant effects. This study aimed to examine the preventive effect of CPE against intestinal damage induced by cyclophosphamide (Cy) in immunosuppressed mice. Thirty-six mice were randomly allocated into three groups: control group (C), model group (M), and treatment group (CPE). The mice in the CPE group were provided with 1500 mg/kg/day of CPE via gavage. In the last 3 days, mice in the groups M and CPE received intraperitoneal injections of 80 mg/kg/day of Cy. The results showed that CPE improved intestinal barrier function by decreasing serum d-Lactate (D-LA) levels and diamine oxidase (DAO) activity, while elevating the relative expression of Occludin, zonula occludens-1 (ZO-1), and mucin-2 (MUC-2) mRNA. Additionally, CPE improved the immune organ index and elevated the levels of secretory immunoglobulin A (sIgA), superoxide dismutase (SOD), interleukin-1beta (IL-1β), interleukin-4 (IL-4), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α) in the intestine, thereby enhancing intestinal mucosal immune function. Furthermore, CPE improved the diversity of intestinal microbiota and increased the abundance of Candidatus_Saccharimonas, Psychrobacter, and Enterorhabdus, which promoted the proper functioning of the intestines. These findings suggest that CPE effectively ameliorates Cy-induced intestinal damage by enhancing the intestinal barrier, improving immune function, and restoring intestinal microbiota. Full article

Silica nanoparticles (SNPs) induce reproductive toxicity through ROS production, which significantly limits their application. The protective effects of taurine (Tau) against SNP-induced reproductive toxicity remain unexplored. So this study aims to investigate the impact of Tau on SNP-induced porcine ovarian granulosa cell toxicity. In vitro, granulosa cells were exposed to SNPs combined with Tau. The localization of SNPs was determined by TEM. Cell viability was examined by CCK-8 assay. ROS levels were measured by CLSM and FCM. SOD and CAT levels were evaluated using ELISA and qPCR. Cell apoptosis was detected by FCM, and pro-inflammatory cytokine transcription levels were measured by qPCR. The results showed that SNPs significantly decreased cell viability, while increased cell apoptosis and ROS levels. Moreover, SOD and CAT were decreased, while IFN-α, IFN-β, IL-1β, and IL-6 were increased after SNP exposures. Tau significantly decreased intracellular ROS, while it increased SOD and CAT compared to SNPs alone. Additionally, Tau exhibited anti-inflammatory effects and inhibited cell apoptosis. On the whole, these findings suggest that Tau mitigates SNP-induced cytotoxicity by reducing oxidative stress, inflammatory response, and cell apoptosis. Tau may be an effective strategy to alleviate SNP-induced toxicity and holds promising application prospects in the animal husbandry and veterinary industry. Full article