Frontiers in Veterinary Science最新文献

Background: The mitral inflow spectral is expressed as two separate waves: early diastolic trans-mitral flow velocity (E) and late diastolic trans-mitral flow velocity (A) waves. When the heart rate (HR) increases and the diastolic time diminishes, the mitral flow pattern changes from EA-separation to EA-fusion. The E wave provides information about preload and diastolic function. Tissue Doppler imaging (TDI) and non-invasive intraventricular pressure gradient (IVPG) based on color-M-mode echocardiography are two techniques established in recent years with good repeatability in cardiac function evaluation, especially diastolic.

Hypothesis/objective: We hypothesize that IVPG and E/E' are differentially influenced by mitral inflow patterns.

Animals: A total of 66 hypertensive cardiomyopathy (HTN-CM) induced by abdominal aorta coarctation and 33 sham-operated rats were divided into 6 groups according to trans-mitral flow patterns.

Methods: Conventional echocardiography, TDI, and IVPG sampling were performed on rats under general anesthesia with 2.5% isoflurane at 3 weeks after the operation. After code EA-separation = 1, EA-half-separation = 2, and EA-fusion = 3, Pearson's correlation tests were performed.

Results: Both E and E' in EA-fusion (1.04 ± 0.13 and 7.65 ± 0.84) are higher than the EA-separation pattern in all rats (0.91 ± 0.10 and 5.51 ± 0.78, p < 0.001). The preload change has more impact on E' than E (0.443 vs. 0.218, p < 0.001, respectively), which leads to decreased E/E' in EA-fusion. Total IVPG and basal IVPG positively correlated with the mitral inflow pattern (0.265 and 0.270, p < 0.001), while mid-to-apical IVPG was not (0.070, p = 0.281).

Conclusion: The mitral inflow pattern positively correlates with basal IVPG, E, and E'. Mid-to-apical IVPG was independent of mitral inflow patterns, while E/E' tended to be lower when the mitral inflow pattern changed from EA-separation to EA-fusion.

Giardia intestinalis is a widespread protozoan parasite associated with significant health risks in humans and animals. However, there is a lack of epidemiological data regarding this parasite in fur-animals. The present study aimed to investigate the prevalence and assemblage distribution of G. intestinalis in fur-animals in northern China. A total of 871 fecal samples were detected by nested PCR. The results showed an overall infection rate of 1.15%, with the highest rate in Hebei province (2.28%), while no positive cases were observed in Jilin and Heilongjiang provinces. Although no significant differences were found in species group, raccoon dogs (1.72%) were more susceptible to infection than mink (1.40%) and foxes (0.57%). Additionally, the highest infection rate was observed in farms with fewer than 2,000 animals (1.41%), followed by farms with ≥5,000 (0.93%) and those with 2,000-5,000 animals (0.75%). The infection rate was higher in juvenile animals (1.35%) compared to adults (1.08%), and in non-diarrheal animals (1.16%) compared to diarrheal animals (1.08%). Notably, this study is the first to report assemblage A in mink, this finding highlight the potential role of mink as a reservoir for zoonotic transmission. Assemblage D was detected in foxes and raccoon dogs, further suggesting that these animals may serve as potential zoonotic reservoirs. These findings not only complements the epidemiological data of G. intestinalis in fur-animals but also emphasize the importance of monitoring the fur industry to mitigate public health risks.

Aichivirus D (AiV-D), a newly emerging member of the Kobuvirus genus, is associated with diarrhea in cattle. This study aimed to investigate the prevalence and molecular characteristics of AiV-D among dairy cattle in China. From October 2021 to August 2022, 279 fecal samples were collected from diarrheal dairy cattle across seven provinces in China. Among these, 37 samples (13.2%) tested positive for AiV-D by RT-PCR, indicating a wide geographical distribution of AiV-D in Chinese dairy cattle. Phylogenetic analysis based on the complete VP1 gene revealed that Chinese dairy cattle AiV-D strains belong to the AiV-D2 genotype, with unique amino acid changes in VP0, VP3, and VP1 that distinguish them from known AiV-D strains. Additionally, an AiV-D strain was successfully isolated, and its complete genome was sequenced. Phylogenetic analysis of the complete genome and individual genes confirmed the strain's classification within the AiV-D2 genotype. This study reports the first detection of the AiV-D2 genotype outside Japan, highlighting the need for future surveillance to better understand the epidemiology and diversity of AiV-D in China.

Introduction: Foot-and-mouth disease (FMD) is a highly contagious disease caused by FMDV, resulting in vesicular lesions in cloven-hoofed animals and posing significant economic threats to the livestock industry. VLP vaccines, which lack viral genetic material and are non-infectious, demonstrate superior safety compared to traditional inactivated vaccines. This study employs ADDomer, a novel adenovirus-based VLP framework, to display FMDV antigenic epitopes on the VLP surface. Additionally, FMDV capsid proteins can assemble into VLPs, offering innovative approaches for developing more efficient and safer FMDV vaccines.

Methods: Two FMDV VLP proteins were constructed using a baculovirus expression system. One VLP was developed by embedding the B-cell epitope of FMDV VP1 into the G-H loop of VP3 and co-expressing it with VP1 and VP0 to form VP1-VP3_B-VP0. The other VLP, ADDomer-BBT, fused B-and T-cell epitopes from FMDV O-type VP1 into the ADDomer platform, with porcine CD154 expressed as an immune enhancer. Expression conditions were optimized, and proteins were purified. The VLPs, combined with porcine CD15 molecular adjuvant, were evaluated for immunogenicity in piglets.

Results: After purification, both VLPs displayed virus-like structures under electron microscopy. Immunization in piglets induced high levels of FMDV-specific and neutralizing antibodies, enhanced cytokines IL-2, IL-4, and IFN-γ, and increased lymphocyte proliferation. The CD154-added group showed higher immune responses.

Discussion: The VLP vaccines effectively induced strong cellular and humoral immune responses, with CD154 enhancing efficacy. These findings provide insights for developing safer, more effective FMDV vaccines and contribute to advancing livestock health and productivity.

Pain management in horses plays a pivotal role in the therapeutic approach to several diseases. Horses have cannabinoid receptors at the level of dorsal root ganglia, blood vessels, and synoviocytes that can be up or down- regulated by inflammatory conditions, justifying the possible efficacy of exogenous cannabinoids (i.e., phytocannabinoids) in managing several painful pathologies in this animal species. However, the current use of supplements containing cannabidiol (CBD) in equines is based on anecdotal evidence, without the support of sufficient pharmacokinetic studies. In humans, the concentration peak of CBD and the area under the concentration-time curve (AUC) are both strongly influenced by food administration. Also, in equids, the oral bioavailability of some drugs can be influenced by the meal but no information is available about CBD. This study investigated the pharmacokinetics of CBD following single oral administration of two different formulations of pure CBD (oil and paste), dosed at 1 mg/kg, at two different times about food administration. CBD oil and CBD paste were administered orally at 1 mg/kg to eight healthy horses according to a cross over design, and blood samples were taken at pre-fixed time-points for the pharmacokinetic analyses. The obtained pharmacokinetic data did not allow for statistically significant differences between formulations (paste or oil) and feeding time (fed and fasted status). However, following treatment with the paste, the Cmax was achieved in a shorter time range compared to the oily formulation, indicating that it could be a better formulation to consider in future equine studies.

Introduction: Animal health is essential to ensure the highest level of animal welfare and to conserve resources. Especially in naturally ventilated barns, the airborne entry of pathogens is difficult to avoid. For instance, birds in naturally ventilated turkey barns are frequently infected by highly pathogenic avian influenza and the airborne route may play a role. In this study, a naturally ventilated turkey barn was equipped with filter modules that allow a conversion to a mechanically ventilated barn.

Methods: Four filter modules with two filter stages were adapted to a turkey barn and the curtains were closed to induce a slight overpressure in the barn. Air samples were taken over the course of 16 months in front of and behind the filter units to assess the filter efficiencies. Filter efficiencies were evaluated by the reduction of particle classes (PM1, PM10, nanoparticles), microorganisms (total bacteria, molds, yeasts), and the detection of potentially pathogenic bacteria and viruses by PCR tests.

Results: Particle reduction rates were 94.17% for PM1, 94.27% for PM10, and 95.80% for nanoparticles, respectively. Total bacteria counts were reduced by 95.88%, molds by 94.64%, and yeasts by 66.03%. Ornithobacterium rhinotracheale was significantly retained in the filter units. The results for influenza A also indicated that the entry of potentially infectious particles could be prevented.

Discussion: The flexible switch from a naturally to a mechanically ventilated barn with filtered supply air can be an innovative solution to avoid airborne pathogen entry in risky situations and may represent a component in the strategy to control epidemic diseases.

Aim: Clostridium species, such as Clostridium perfringens, C. baratii, C. colicanis, Paraclostridium bifermentans, and Paeniclostridium sordellii, are Gram-positive, anaerobic, endospore-forming bacteria with diverse pathogenic mechanisms. While these species are commensals in the guts of variable animal species, such as anteaters, they are less frequently found in humans. The diet of anteaters, which includes chitin and formic acid, plays an important role in their specific dietary habits, as well as in clostridial metabolism.

Methods and results: This study investigates the metabolic diversity and responses of anteater clostridial isolates to various substrates, namely chitin, chitosan, cellulose, N-acetyl-D-glucosamine (NAG), and glucose. All tested clostridia were able to grow in the presence of chitin, cellulose, NAG, and glucose, but varied in metabolite production. However, the presence of chitosan surprisingly showed an antimicrobial effect against clostridia, especially Pae. sordellii, P. bifermentans, and C. colicanis. The results demonstrate significant variations in fermentation profiles, and metabolite production across substrates and clostridial species. Acetate production was detected as common for all tested clostridia despite species variability and incoming substrates, as well as lactate, butyrate, propionate, and formate for some strains.

Conclusion: In relation to digestion, anteater clostridia could play an important role in chitin and its degradation products, which, in the end, can influence clostridial occurrence and pathogenicity via chitosan.

A 10-month-old intact female Cane Corso dog was referred to the Veterinary Teaching Hospital of the University of Perugia (PG-VTH) for severe hemolytic anemia and thrombocytopenia. The dog had never traveled abroad and was regularly treated with antiparasitic products. On physical examination, the dog showed lethargy, delayed growth, weight loss, pale mucous membranes, and abdominal pain. The temperature was normal, and on examination, no ectoparasites were observed on the animal's body surface. The main laboratory findings were hemolytic anemia, thrombocytopenia, and elevated liver enzymes. Babesia infection was initially diagnosed by blood smear evaluation via May-Grünwald-Giemsa staining and then confirmed by real-time polymerase chain reaction analysis; further sequencing analysis attributed the infection to Babesia vulpes (B. vulpes). An initial treatment with imidocarb dipropionate was only partially effective, while resolution of the infection was reached afterward with a combination of Malarone^® and azithromycin therapy. To the authors' knowledge, this report describes the first case of B. vulpes infection in a dog in Italy.

Aerosolized endotoxins such as Lipopolysaccharide (LPS), found in livestock environments, induce an inflammatory mediator cascade. Poultry are commonly exposed to LPS over the growth cycle; however, little is known regarding the cumulative impact of intramuscular LPS injection and its effects on immune cellular metabolism, pathway preferences, and clearance response. Utilizing a LPS model in chickens can offer insight into host immune responses and provide a better understanding of immune tolerance to this endotoxin and major component of Gram-negative bacteria. Therefore, the study objectives were to compare metabolic phenotypes and immune profiles of isolated peripheral blood mononuclear cells (PBMC) from two ages of adult White Leghorn roosters before and post-LPS injection. A total of 20 adult White Leghorn roosters aged 1 yr. or 2.5+ yrs. were randomly assigned to sterile saline or 1 mg/kg body weight LPS (Escherichia coli O55:B5, LPS) injected intramuscularly across 4 sites in breast and thigh muscles. Body weight was recorded before injections at baseline and 24 h post-injection (hpi). Cloacal temperature and blood collections were performed at baseline, 6 hpi, and 24 hpi. PBMC were isolated for Agilent Seahorse XF metabolic analysis and multicolor flow cytometry. Plasma was collected for a C-reactive protein (CRP) enzyme-linked immunosorbent assay. Statistical analysis was performed using the MIXED procedure with fixed effects of age, injection status, and age X injection interaction followed by Tukey-Kramer adjustment (SAS 9.4), with significance denoted at p ≤ 0.05. Aged roosters were found to have fewer CD3⁺CD8α⁺ T cells at baseline compared to younger roosters (p < 0.05) while generally displaying delayed immunometabolic changes post-LPS injection compared to younger roosters. Young roosters administered LPS had significantly reduced CRP at 6 hpi compared to control, while aged roosters significantly increased CRP production by 24 hpi (p < 0.05). Both ages responded similarly to inhibitory assays, suggesting that the ability to respond was not different based on age. Overall, results suggest adult roosters may respond differently to LPS injection based on age and immune cell presence, likely due to accumulated exposure to LPS in poultry environments.

Kidney diseases are observed in various wild animal species, more often noted in captive than in free-ranging animals. There are few reports in roe deer (Capreolus capreolus). Two kidney malformations were encountered while reviewing and collecting the roe deer samples. Kidney malformations were found in samples from two roe deer in Central Poland, one in 5-year-old female near Węgrów (50 km northeast of Warsaw) and one in 7-year-old male near Rawa Mazowiecka (75 km southwest of Warsaw). The female had a smaller (5 cm long and weighed 20 g) shrunken kidney (no prominent histopathological changes) and compensatory hypertrophy of the other kidney (weighting 85.8 g). A diagnosis of renal hypoplasia was made. The male had a smaller kidney (4.5 cm long and weighed 15.3 g) and normal-sized the other kidney (7.5 cm and 55.6 g). Massive mononuclear infiltrates composed mainly of lymphocytes and plasma cells in the renal interstitium, with hyperplasia of the connective tissue and multifocal glomerular sclerosis, were found in both kidneys. Diagnosis of chronic interstitial nephritis was made.