BMC Veterinary Research最新文献

Good hygienic milking practices including the disinfection of the cow teat skin before and after milking aimed at preventing the occurrence of new intramammary infections (IMI) in dairy cows. This practice is generally performed using disinfectants, and in the current context of attention to the emergence of resistances, it is of greatest interest to evaluate alternative solutions that can expand treatment options. We assessed the efficacy of a pre-dipping and a post-dipping product based on the bacteriocin-containing culture of Lactococcus cremoris strain FT27, as compared to commercial disinfectants. FT27 was selected for the bactericidal activity in vitro against food pathogens. In the present study, it also revealed a high bactericidal activity against the main mastitis pathogens, most likely related to Nisin A production, according to genomic and proteomic analysis. The lactococcus-based preparations were applied in two commercial dairy farms in Northern Italy. Overall, 298 dairy cows were enrolled, 141 in the treated group (TR), and 157 in the control group (CTR). The cows were sampled at quarter level every two weeks for 3 months. During the trial, all cows showed a good health status. The hygiene level for udder, flanks and legs was generally good (on average < 3 score); the udder hygiene was significantly worse (P < 0.01) in the CTR group. The teat apex hyperkeratosis was overall low (on average < 2 score). We recorded no significant differences between the two experimental groups in the Somatic Cell Count (SCC) values and the bacteriological results. The overall frequency of new IMI was low, ranging 0.6 - 0.5% for S. aureus in the TR or CTR group respectively, to 2.6-4.4% for NASM. Regarding Str. spp., the new IMI accounted for 1.7% or 1.9% in the TR or CTR group, respectively. Notably, the incidence of S. aureus new IMI did not increase during the study, even though neither of the two herds segregated the positive cows. The non-inferiority test showed that the Lactococcus-based pre- and post-dipping products had an efficacy comparable to proven commercial disinfectants in maintaining udder health and preventing new IMI, thus representing a possible alternative to current teat dip products.

The study was focused on the anatomical characteristics of the Egyptian long-eared hedgehog's oral cavity by using gross and scanning electron microscopic examinations. The upper lip had an elongated T-shaped snout-like structure. The hard palate had a triangular rostral part (which had a semicircular area and a caudal ridged area with the first 3 or 4 ridges) and a caudal part (which contained seven or eight slightly oblique ridges with raphae). The diamond-incisive papilla is flanked on both sides by a groove and a fissure. The hard palate surface had glandular openings and a microplicae system. The uneven, soft palate's surface had multiple grooves and folds with 12-16 Gemmal papillae. The Gemmal papillary surface had three to four taste pores with microplicae and glandular openings. The dorsal lingual surface had six filiform subtypes: pointed (on the tip, rostral border, and median apical region), triangular (on the lateral apical and circumvallate regions), bifurcated (on the median tip only), leaf-like (on the median body region), branched (on the lateral root region), and small pointed papillae (on the median root). There were two fungiform subtypes: ovals (on the rostral border and lateral region) and rounds (on the median apical region and body). The caudal root part had a triangular arrangement of three circumvallate papillae. In conclusion, the finding confirmed its oral cavity adaptation with its insectivorous feeding habits and Egyptian environment.

Background: Sodium butyrate is a potential antibiotic growth promoter and has had advantageous effects on the poultry industry.

Methods: Evaluating the effect of sodium butyrate on the intestinal villi and the humoral part of innate immunity of the male Cobb 500 broiler using scanning electron microscopy and quantitative real-time PCR analysis, the control group and treated group of Cobb 500 with SB supplemented received water containing 0.98 mg sodium butyrate.

Results: The administration of sodium butyrate changed the villi characters, as the shape changed from tongue to long tongue. They were mainly parallel to each other and long finger-like at the duodenum. The tips of the villi in the control group appeared thin-slight curved with a prominent center in the duodenum, thin rectangular in the jejunum, and ileum in the control group. In contrast, in the treatment group, they changed to thick rectangular in the duodenum and ileum zigzag shape in the jejunum. The epithelium lining of the duodenal villi showed a dome shape, the jejunal villi showed a polygonal shape, and the ileal villi appeared scales-like. The epithelium lining showed irregular microfolds and many different-sized pores, and the treatment group showed islands of long microvilli in the duodenum and solitary long microvilli in the ileum. Real-time PCR of AvBD 1, 2, 10, and 12 significantly (P < 0.01). The better expression of AvBD 1, 2, and 12 was determined in the duodenum, while AvBD 10 was in the jejunum.

Conclusion: Sodium butyrate enhanced the chicks' growth and small intestine parameters, modified the morphology of the intestinal villi, and improved the humoral part of innate immunity.

Background: Nipah virus (NiV) is a zoonotic pathogen that poses a significant threat because of its wide host range, multiple transmission modes, high transmissibility, and high mortality rates, affecting both human health and animal husbandry. In this study, we developed a one-step reverse transcription droplet digital PCR (RT-ddPCR) assay that targets the N gene of NiV.

Results: Our RT-ddPCR assay exhibited remarkable sensitivity, with a lower limit of detection of 6.91 copies/reaction. Importantly, it displayed no cross-reactivity with the other 13 common viruses and consistently delivered reliable results with a coefficient of variation below 10% across different concentrations. To validate the effectiveness of our RT-ddPCR assay, we detected 75 NiV armored RNA virus samples, mimicking real-world conditions, and negative control samples, and the RT-ddPCR results perfectly matched the simulated results. Furthermore, compared with a standard quantitative real-time PCR (qPCR) assay, our RT-ddPCR assay demonstrated greater stability when handling complex matrices with low viral loads.

Conclusions: These findings show that our NiV RT-ddPCR assay is exceptionally sensitive and provides a robust tool for quantitatively detecting NiV, particularly in stimulated field samples with low viral loads or complex matrices. This advancement has significant implications for early NiV monitoring, safeguarding human health and safety, and advancing animal husbandry practices.

Background: We aimed to investigate the association between selected inflammatory and immune variables and survival of dogs with myxomatous mitral valve disease (MMVD). We evaluated data of 62 client-owned dogs with MMVD, grouped into preclinical, stable congestive heart failure (CHF) and unstable CHF. Univariate Cox proportional hazards regression analysis was used to quantify the association of white blood cell count, concentrations and percentages of T lymphocytes and their subtypes (T helper lymphocytes, cytotoxic T lymphocytes, double positive T lymphocytes, double negative T lymphocytes) and B lymphocytes with survival. P values < 0.1 in individual groups and P values < 0.05 in the group of all patients were considered significant. Spearman correlation coefficients between significant covariates were calculated to assess the relationships among variables and with survival.

Results: In the preclinical group, percentage of double positive T lymphocytes was negatively associated with survival (hazard ratio (HR) = 2.328; P = 0.051). In the unstable CHF, T lymphocyte (HR = 1.613; P = 0.085), cytotoxic T lymphocyte (HR = 1.562; P = 0.048), double positive (HR = 1.751; P = 0.042), and double negative T lymphocyte (HR = 1.613; P = 0.096) concentrations were negatively associated with survival, as well as cytotoxic T lymphocyte (HR = 1.502; P = 0.007) concentration in the group of all patients. The percentage of T helper lymphocytes was positively associated with survival in the unstable CHF (HR = 0.604; P = 0.053) and in the group of all patients (HR = 0.733; P = 0.044). The concentration of cytotoxic T lymphocytes positively correlated with left atrial to aortic ratio (LA/Ao) (rho = 0.259, P = 0.037), and peak velocity of early diastolic mitral flow (rho = 0.259, P = 0.039), whereas the percentage of T helper lymphocytes negatively correlated with left atrial to aortic ratio (LA/Ao) (rho = -0.212, P = 0.090) and early to late mitral flow ratio (rho = -0.232, P = 0.072).

Conclusions: Cytotoxic T lymphocytes, T helper lymphocytes, double positive and double negative T lymphocytes as well as biomarkers cardiac troponin I, N-terminal pro-B-type natriuretic peptide, C-reactive protein are implicated in the progression of MMVD.

Background: Pigeons (Columba livia) are mainly raised as a source of animal protein, racing, leisure and as an experimental animal. The present study investigated the morphology of the esophagus in the young and adult domestic pigeon, Columba livia domestica.

Methods: Ten young and ten adult, normal, and healthy pigeons were collected from the local breeders. Samples from different parts of esophagus and crop were examined grossly, by stereomicroscopy, scanning and light microscopy.

Results: The esophagus consisted of a long cervical part, a crop, and a short thoracic part. The crop was represented by a thin-walled outpouching with two lateral diverticula. The mucosa presented wavy fine folds in the cervical esophagus, irregular folds in the lateral diverticula giving it a corrugated appearance, and prominent longitudinal folds with several gland openings in the middle and lower parts of the crop, as well as in the thoracic esophagus. The density of gland openings was higher in adult pigeons than that in young pigeons. The mucosa of the esophagus was lined by non-keratinized stratified squamous epithelium. The shape, height, and branching of the mucosal folds differed between young and adult pigeons. Mucous-secreting alveoli were detected in the middle part of the crop as well as in the thoracic esophagus, but not in the cervical esophagus or lateral diverticula of the crop.

Conclusion: The variations between the young and adult pigeons suggest a functional adaptation of adult pigeons to their diet compared to young pigeons.

Canine distemper virus (CDV) is a highly contagious and often fatal disease affecting wild and domesticated carnivores. The virus is a single-stranded RNA virus from the genus Morbillivirus and the family Paramyxoviridae. While domestic dogs are the most common hosts, the virus poses a significant threat to endangered wildlife due to its broad host range. This study aimed to characterize the CDV Haemagglutinin (H) gene in golden jackals and explore the molecular evolution of the virus in an underrepresented host. A total of 88 brain samples from hunted golden jackals were tested for the presence of CDV viral nucleic acid, and the H gene of positive samples was amplified and sequenced using the Sanger method. Phylogenetic analysis, conducted using maximum likelihood methods, revealed that all Serbian sequences clustered within the Arctic lineage. Notably, the analysis identified a tyrosine (Y) at position 549 of the H protein, a mutation commonly associated with wildlife hosts, instead of the histidine (H) typically found in domestic strains. Additionally, a mutation at position 310 was observed, which could potentially affect the protein's function and virus-host interactions. These findings provide valuable insights into the genetic diversity and evolutionary dynamics of CDV in golden jackals, with broader implications for understanding the virus's adaptability to different hosts. Further research is needed to investigate the functional impact of these mutations, particularly their role in vaccine efficacy and disease transmission across wildlife and domestic species.

Background: The hedgehogs have been recently identified as possible reservoir of Middle East respiratory syndrome coronavirus like (MERS-CoV-like). These viruses were classified as a distinct Betacoronavirus erinacei (BCoV-Eri) species within the MerBCoV-Eriirus subgenus. As coronaviruses are known for their ability to jump between different hosts, including humans, this can pose a particular threat to people in direct contact with hedgehogs, such as those working at animal asylums. Our previous studies have shown the presence of BCoV-Eri strains in animals collected in the wildlife rehabilitation centre. This study aimed to investigate the presence of CoV in subsequent hedgehogs collected from the urban area of Poland and their molecular characteristics.

Results: Monitoring for the presence of coronavirus infection in hedgehogs revealed five positive individuals. The presence of BCoV-Eri was found in a total of 20% of animals tested. Our analyses revealed no correlation between CoVs positivity and animal health conditions but a higher probability of such infection in juveniles and females. The whole genome of two Polish Hedgehog coronavirus 1 strains were sequenced and compared with available counterparts from European and Asian countries. Phylogenetic analysis showed that both CoV strains formed common cluster with other similar MerBCoV-Eriirus, but they were also found to be genetically variable and most changes in the S protein were identified. Our analysis revealed that some S protein sites of the Hedgehog coronavirus 1 strains evolved under positive selection pressure and of five such sites, three are in the S1 region while the other two in the S2 region of the Spike.

Conclusions: BCoV-Eri is to some extent prevalent in wildlife asylums in Poland. Given that the S protein of BCoVs-Eri is highly variable and that some sites of this protein evolve under positive selection pressure, these strains could potentially acquire a favourable feature for cross-species transmission. Consequently, the threat to humans working in such asylums is particularly high. Adequate biosecurity safeguards, but also human awareness of such risks, are therefore essential.

Background: Zinc nanoparticles (NPs) are characterized by high bioavailability, small size, and high absorbability. The purpose of this experiment was to determine the effect of Zn-NP feed supplementation on ruminal fermentation, microbiota, and histopathology in lambs. In vitro (24 h), short-term (STE, 28 d), and long-term (LTE, 70 d) experiments were performed. The lambs in STE were fed a basal diet (BD) composed of 350 g/d ground barley and 700 g/d meadow hay (Control), BD enriched with ZnO-NPs (80 mg Zn/kg of diet, ZnO-NPs), and BD enriched with Zn phosphate-based NPs (80 mg Zn/kg of diet, ZnP-NP). The in vitro gas production technique was used in incubated rumen fluid from STE. The lambs in LTE were fed BD (Control), BD enriched with ZnO-NPs (40 mg Zn/kg of diet, ZnO-NP40), BD enriched with ZnO-NPs (80 mg Zn/kg of diet, ZnO-NP80) and BD enriched with ZnO (80 mg Zn/kg of diet, ZnO-80).

Results: After 24 h of incubation, dry matter digestibility was higher for ZnO-NP and ZnP-NP substrates than the control in an in vitro experiment (P < 0.001). The total bacterial population in the STE was lower (P < 0.001) in the ZnP-NP group than in the control and ZnO-NP groups, but the protozoan populations were not significantly different. The ammonia-N concentration in LTE was lowest in the ZnO-NP80 group (P = 0.002), but the activities of carboxymethyl cellulase (P < 0.001) and xylanase (P = 0.002) were higher in the ZnO-NP40, ZnO-NP80, and ZnO-80 groups than in the control group. Morphological observation after STE and LTE revealed histological changes (e.g. inflammation of the epithelium or edema of the connective tissue) in the rumen of lambs.

Conclusion: Zn-NP supplementation up to 70 d improved feed-use efficiency and influenced ammonia-N concentration and activities of hydrolases in the rumen. The active ruminal fermentation affected the health of the ruminal papillae and epithelium in the lambs, regardless of the application's form, dose, or duration. However, by affecting rumen microbial fermentation, Zn-NPs could alter fermentation patterns, thereby increasing the capacity of host rumen epithelial cells to transport short-chain fatty acids.

Curcumin, the main polyphenol component of turmeric powder, has garnered increasing attention as an effective supplement in fish diets. A comparative trial was conducted to evaluate the impacts of dietary supplementation with different forms of curcumin (free, in combination, or nanoparticles) on hemato-biochemical parameters, reproductive capacity, and related gene expressions of red tilapia (Oreochromis niloticus x O. mossambicus) broodstock. Fish (n = 168) were fed an isonitrogenous (30% CP), isocaloric (18.72 MJ kg - 1) diet containing basal diet (Control), 60 mg kg-1 of either free curcumin (Cur), curcumin/nano-curcumin blend (Cur/NCur), or nano-curcumin (NCur) for 56 days. Red tilapia broodstock (155 ± 5.65 g) were stocked at a male: female ratio of 1:3. Blood samples and gonads were collected to assess hemato-biochemical parameters, reproductive capacity, and related gene expression at the end of the feeding trial. The results indicated that the values of hematological parameters (RBCs, WBCs, hemoglobin), total protein, albumin values, and reproductive hormones (T, LH, and FSH) were significantly increased, while liver function enzymes were decreased in the NCur group (P < 0.05). Reproductive performances (GSI, gonad maturation, total number of fry per female) were significantly improved in the NCur group compared with those in other groups (p < 0.05). The expression of reproductive genes (CYP19A1A, FSHR, LHR, FOXL2A, ESR1, ESR2A, and PGR) were significantly up-regulated in the gonads of fish fed NCur. Collectively, feeding red tilapia diets containing NCur led to noticeably better results followed by Cur/NCur blend, then free Cur compared to the control diet. These results indicate the superiority of NCur over its free or blended form, suggesting that a diet containing about 60 mg/kg of NCur is beneficial for enhancing hemato-biochemical parameters, improving reproductive performance, and enhancing the gonadal architecture of red tilapia.