BMC Veterinary Research最新文献

Background: Increasingly exposed to emerging sanitary risks, extensive livestock farming systems are confronted with the imperative of incorporating biosecurity measures in their production models in order to limit the risk of introduction and diffusion of animal pathogens. Yet, ex-ante assessment methods of the likelihood of biosecurity measures implementation are poorly documented. Our study aimed at comparing alternative methods of elicitation of preferences to assess the attitude of extensive livestock farmers towards biosecurity measures. We used, as a case study, the Regional Porcine Sanitary Plan (RPSP) elaborated for the free-range pig sector of Corsica Island to meet the newly established national disease prevention requirements of France in the face of risk of African Swine Fever introduction.

Methods: The RPSP imposed (1) a fencing of the breeding pigs' area, (2) the neutering of the pigs not used for breeding, and (3) a management process of dead pigs' carcasses found on pastures. We evaluated four attributes of the sanitary plan, including (1) proportion of the implementation cost covered by state subsidies, (2) mandatory carcass management, (3) people allowed to neuter gilts, (4) the age limit for neutering. We performed interviews of a sample of free-range pig farmers using three methods in parallel, namely (1) direct qualitative elicitation, (2) attributed-based stated choices and (3) semi-quantitative ranking of attributes.

Results: Farmers' preference for a high subsidization of the sanitary plan and for enforcing the neutering of pigs at an early age was consistent across all used methods. Participants expressed heterogeneous preferences for the two other attributes. Half of the respondents were reluctant to entrust veterinarians with neutering gilts while the other half deemed veterinarians' intervention compulsory. Contradictory preferences were obtained on rendering carcass management mandatory depending on the elicitation method.

Conclusion: Our study demonstrates the added value of using choice-based methods, where respondents weigh the individual costs and benefits associated with different options, in combination with qualitative or semi-quantitative ranking methods in which farmers express their opinions and give more consideration to their community interest. It also reveals potential issues of heterogeneities among farmers' preferences that need to be taken into consideration in similar surveys.

Background: Although several risk factors have been suggested for uterine torsion, the pathogenesis is still unclear. Therefore, the current study aims to investigate the pathogenesis of uterine torsion by assessing the histological, histochemical, and immunohistochemical changes that occur in the placenta obtained from uterine torsion cases. Immunohistochemical changes include investigation of the expression of estrogen receptors (ERs), progesterone receptors (PRs), and the vascular endothelial growth factor (VEGF) in the placental tissue.

Methods: Forty intrapartum dairy cows were included in this investigation. The cows were divided into two equal groups. The first group was the uterine torsion (UT) group, while the second group was the normal control group (Ctrl). After caesarian section treatment, placentas were collected from all animals in the study. Histopathological, histochemical, and immunohistochemical examinations were performed. Estrogen receptors, progesterone receptors, and vascular endothelial growth factor expression in the placenta were evaluated.

Results: The results revealed numerous trophoblast giant or binucleate cells in the trophoblastic epithelium. Through Masson's trichrome technique, the distribution of collagen fibers as shiny, blue-colored stripes on the fetal mesenchyme was observed. Additionally, the results showed a strong, intense PAS-positive reaction in the cytoplasmic vesicles of most trophoblastic cells due to mucopolysaccharides. The immunohistochemical findings of the UT placenta revealed moderate to weak staining for ERs in contrast to those of the Ctrl placenta, which revealed moderate staining for ERs. In addition, non-statistical differences in the expression of PRs were found between the two tested groups. For VEGF, strong positive immunoreactivity was found in the Ctrl group compared to the UT group, which exhibits a general absence in many trophoblast cells.

Conclusion: It can be concluded that significant variation was observed in the placentas obtained from buffaloes suffering from UT compared to those obtained from normal pregnant ones. These significant variations were involved in the decreased expression of ERs and VEGF in the UT group compared to the normal Ctrl one. Investigating the expression of these placental molecules may monitor the changes in the placental tissue and provide insight into the pathogenesis of UT.

Background: The Highly Pathogenic Island (HPI) found in Yersinia pestis can be horizontally transferred to E. coli, enhancing its virulence and pathogenicity. Ubiquitin (Ub) acts as an activator of the NF-κB pathway and plays a critical role in the inflammatory response. However, the precise mechanism by which Ub and the regulated TLR4/NF-κB pathway contribute to HPI-induced intestinal inflammation in E. coli remains unclear.

Results: In this study, we established Ub overexpression models of small intestinal epithelial cells (in vitro) and BALB/c mice (in vivo) and infected these models with HPI-rich E. coli. We investigated the role of the Ub-regulated TLR4/NF-κB pathway in E. coli HPI-induced intestinal inflammation through qPCR, ELISA, immunofluorescence, immunohistochemistry, and H&E staining. Our findings confirmed that E. coli HPI promoted the expression of Ub, TLR4, and NF-κB in IPEC-J2 cells and induced the translocation of NF-κB p65 protein to the nucleus. Further investigations revealed that Ub overexpression enhanced epithelial cell damage induced by E. coli HPI. This was accompanied by up-regulation of mRNA levels of TLR4, MyD88, NF-κB, IL-1β, and TNF-α, as well as increased release of the inflammatory factors IL-1β and TNF-α. In a mouse model with Ub overexpression infected with E. coli HPI, we observed that Ub overexpression promoted E. coli HPI-induced intestinal inflammation. Mechanistically, E. coli HPI induced intestinal epithelial cell damage by inducing Ub overexpression and modulating the TLR4/NF-κB pathway.

Conclusions: In conclusion, this study sheds light on the significant role of the Ub-regulated TLR4/NF-κB pathway in E. coli HPI-induced duodenitis, offering novel insights into the pathogenesis of E. coli infections.

Background: An advanced curriculum for training Total Laparoscopic Gastropexy (TLG) was developed using the CVLTS-composed simulator based on an ergonomic model of a canine abdominal cavity. The performance of Veterinary surgeons trained in basic laparoscopic surgical skills during 15 training TLG sessions (experimental group, n = 10) was compared to the TLG performance of veterinary surgeons with intermediate (n = 10) or advanced (n = 6) laparoscopic skills. The transfer of surgical skills to a live model was assessed by performing TLG in fattening pigs under operating room conditions using barbed sutures. Experimental group performance after accomplishing the TLG training curriculum and all groups' performance during TLG in the in vivo model were videotaped and evaluated by external Minimally Invasive Surgery (MIS) experts using the GOALS and TLG-specific ranking (SRS) scales. Also, a quantitative assessment comprising time, smoothness of movements, and angular displacement using a Hand Movement Assessment System (HMAS) was performed. Besides, a postmortem biopsy recovered from the gastropexy site three months after surgery to evaluate gross and microscopic characteristics by histopathology was analyzed.

Results: GOALS and SRS scores (P < 0.05), and time, smoothness of movements, and angular displacement during TLG (P < 0.01) significantly improved in the Experimental group after training. They also compared their performance with expert and intermediate groups (P < 0.05) performances. The learning curve for intracorporeal suture stabilized since the tenth (out of 15) training session. Besides, trainees achieved significant TLG skills' in vivo transfer, with no significant difference from the intermediate and expert group performances. The presence of mature collagen (100% of cases), cartilage and bone metaplasia, and foreign body reaction (25% of cases) were found at histopathology evaluation of the gastropexy site, evidencing normal healing.

Conclusion: The TLG training curriculum supported the acquisition of TLG surgical skills in the training box and their transfer to the in vivo model. The experimental group's TLG performance in vivo did not significantly differ from the intermediate and expert groups. The clinical outcome and histopathological findings evidenced complete gastropexy-site healing.

Background: Infectious diseases including Newcastle disease (ND) impair poultry productivity and represent a significant burden to sustainable agriculture in Nigeria. This study aimed to investigate the active circulation and seroprevalence of Newcastle disease virus (NDV) caused by virulent forms of avian paramyxovirus type-1 (APMV-1) in poultry at live bird markets (LBMs) across Nigeria.

Methods: A cross-sectional study of 18 LBMs was conducted within three states in Nigeria (Kano, Oyo, and Abuja). Paired swab and tissue samples (n = 413) were collected from birds on FTA cards and tested for APMV-1 using real-time reverse transcription polymerase chain reaction (rRT-PCR). A subset of rRT-PCR-positive samples were selected for whole genome sequencing based on the originating species (chicken, duck, geese), date, and market location to provide a broad range of isolates for characterisation. Blood samples (n = 405) were also collected from birds and the seroprevalence of APMV-1 antibodies was measured using an enzyme-linked immunosorbent assay (ELISA).

Results: APMV-1 RNA was detected in 21.5% (89/413) of samples from LBMs by rRT-PCR. At least one APMV-1 positive sample was detected in 55.6% (10/18) of LBMs. The largest proportion of APMV-1-positive markets was in Kano (83.3%, 5/6), whereas the lowest was in Oyo (16.7%, 1/6). Assessment of genetic data demonstrated that genotype XIV.2 APMV-1 was circulating within Nigeria with the viruses detected clustering closely with other Nigerian isolates described previously. The seroprevalence of APMV-1 in birds was 45.9% (186/405) and 94.4% (17/18) of LBMs had at least one APMV-1 seropositive sample (i.e., with at least one APMV-1-antibody-positive bird). The LBMs in Kano had the lowest seroprevalence (88.3%, 5/6).

Conclusions: This study demonstrated that APMV-1 continues to circulate in LBMs in Nigeria. LBM traders, poultry producers, and related industry and policy stakeholders should be aware of the occurrence of APMV-1 and how ND may negatively impact upon poultry production and the livelihoods of poultry farmers and LBM traders. Training initiatives aimed at improving the knowledge of APMV-1 infection and improvements in biosecurity practises and the role of disease mitigation through vaccination are required to reduce the impact of this threat to food security.

Background: The global rise in multidrug-resistant bacteria has significantly undermined the efficacy of traditional antibiotics. Multidrug-resistant Streptococcus suis (S. suis), a pathogen capable of infecting pigs and humans, has been identified as a critical threat, causing severe meningitis and rapid mortality. In response, researchers have increasingly focused on herbal compounds as non-traditional antimicrobial agents, which can inhibit bacterial growth while minimizing the risk of resistance development. This study investigates the mechanism through which andrographolide (AP) restores the susceptibility of S. suis to aminoglycoside antibiotics.

Methods: The intracellular ΔpH in S. suis was assessed using the 2',7' -bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCCF-AM) probe to evaluate alterations in the proton motive force (PMF) following treatment with AP. Non-targeted metabolomics was employed to confirm changes in the metabolic profile of S. suis upon exposure to AP. Finally, an in vivo infection model was utilized to evaluate the therapeutic efficacy of AP in combination with antibiotics.

Results: Extensive in vitro experiments demonstrated that AP significantly enhances the activity of aminoglycoside antibiotics against diverse pathogens, including S. suis. Further studies revealed that bacterial death results from AP-mediated upregulation of the S. suis PMF, which enhances cellular uptake of tobramycin (TOB). Moreover, AP significantly upregulated pyruvate metabolism in S. suis, accelerated the tricarboxylic acid (TCA) cycle, and increased nicotinamide adenine dinucleotide (NADH) production. This metabolic shift further augmented the PMF. Combining AP with aminoglycoside antibiotics significantly reduced bacterial load and organ lesions in various organs in mice.

Conclusion: AP holds promise as an adjuvant to aminoglycoside antibiotics for combating S. suis-induced infections, offering a theoretical foundation for clinical applications.

A comprehensive morphological description of Argyrosomus regius (Asso, 1801) gills was conducted through the gross and scanning electron microscopic examinations in addition to the morphometric analysis of the number, length of the gill rakers and the space between them. The medial surface of the 1st gill arch was differed than that of the other three gill arches. Four gill arche's lateral surfaces contained pear-shaped, circular, and oval-shaped spine groups with varying sizes. The medial surface of the 1st gill arch only had different sizes of pear-shaped and oval groups of spines, while the other gill arches had the same-shaped groups of spines beside the presence of small circular groups. The lateral rakers of the 1st gill arch were long, and only one border carried pointed spines, while its medial rakers were triangular. The rakers of the 2nd, 3rd, and 4th gill arches appeared flask like medially and laterally. There were few folds and tubercles appearing on the primary gill filament surfaces; some folds appeared like the helix on the surface of their parts near the gill arch convex border. This is the first anatomical study on Argyrosomus regius gills and we aimed to reveal the unique structural specifications for gill rakers that related to its feeding behavior and we will contribute to a better understanding of its ecological niche and feeding strategies in its natural environment.

Background: The Universal Declaration of Animal Rights (UDAR), adopted in 1977 by an international NGO inspired by the Universal Declaration of Human Rights and made public the following year, aimed to establish a universal code for human conduct toward animals. The declaration was revised twice, in 1989 and 2018, but it failed to be internationally recognised or adopted. While its global influence remained limited, misinterpretations of its scope and context have proliferated in legal and veterinary documents. To gauge its impact on scientific literature, a scoping review across three databases (Scopus, Web of Science Core Collection, and Google Scholar) was conducted for publications citing the UDAR from 1979 to 2022.

Results: In terms of research field, the UDAR is mostly cited in the fields of law (27%), philosophy, ethics, and religion (17%), clinical medicine (17%), and basic medicine (11%). The 1978 UDAR version was most often cited. Among 305 screened publications, 47.9% contained erroneous or misleading claims about the UDAR. Common errors included linking the UDAR to UNESCO (34.8%) and conferring it universal endorsement or legally binding value (10.2%). More than half (57%, 59/103) of the mentions in the ethics section contained errors, namely confusing UDAR with other animal protection texts. Regarding the type of animal use, most misleading claims were found in scientific publications focusing on the use of animals in research.

Conclusions: The misappropriation of the UDAR risks providing a false sense of legitimacy and moral compass to editors, reviewers, and readers regarding animal use and highlights that the authors are unaware of ethical or regulatory frameworks governing the proper use of animals in science. This is particularly relevant because the 1978 version, which is antithetical to animal use in science, was most often cited, raising concerns about the governance of animal research in some institutions and the efficacy of the peer review process in detecting these errors. Finally, UDAR mentions grew more than the estimated growth of scientific publications worldwide, thus suggesting an increase in its influence.

Background: The definition of wildlife health continues to expand with the recognition that health is more than the absence of disease. Practitioners are working to integrate concepts such as vulnerability, adaptation, and resilience into wildlife health research, surveillance, and management actions. Here, we performed a scoping review to identify scholarly articles from 2008 onwards with a focus on climate change impacts on wildlife health. Searches were conducted in Web of Science, Zoological Record, Scopus, Ovid CAB Abstracts, and ProQuest Dissertations and Theses. Articles were screened for relevance and fed into an AI-based thematic analysis that identified recurring themes across the literature. Each theme was manually reviewed and refined to help describe the scope and depth of existing literature, identify key themes, and assess potential knowledge gaps.

Results: In total, 2,249 citations were retrieved of which 372 were included in further analysis after applying a set of inclusion/exclusion criteria. On closer inspection, 30.4% (113/372) of the papers were focused on climate-associated impacts on vector distribution. For this reason, two thematic analyses were performed, one which only included the subset of papers focused on climate change and vector distribution (n = 113) and another including the remaining papers focused on climate-associated impacts on wildlife health (n = 259). Amongst the subset of papers focused on vector distribution, top themes included concepts related to pathogen transmission dynamics, human/public health, and pathogen prevalence, while health papers focused on concepts related to increasing temperatures, species home ranges and distribution, and changing environmental variables.

Conclusions: A large number of the papers retrieved in the literature search focused on how climate change impacts the distribution and abundance of host, vector, and pathogen species, remaining disease-centric in their approach. Papers including themes related to management actions were limited reflecting some uncertainty on how best to respond and prepare for climate change. Further discussion is needed on how wildlife health concepts can be used to help inform on-the-ground management actions in the face of climate uncertainty, this includes the collection of baseline health data and research into health metrics that could be used as indicators of resilience at the ecosystem level.

Background: Globally, the increase in antimicrobial resistance is of great concern. In Denmark, the pig sector is accountable for the majority of antimicrobial usage in animals. As new-born piglets are at risk of developing infectious omphalitis, and many pigs are treated by antimicrobials within the first days of life, an early and accurate diagnosis of the disease is imperative to maintain animal welfare and reduce the antimicrobial usage. The aim of the present study was to compare histopathological and microbiological findings in piglets clinically diagnosed with and without omphalitis during the first three days after birth.

Results: A total of 98 case piglets with omphalitis and 98 control piglets without omphalitis, based on clinical examinations during the first three days of life, were included. Of the 196 piglets, 79 (38 cases and 41 controls) presented histopathological omphalitis. Post mortem, the volume of the umbilicus was significantly enlarged in cases compared to controls (p = 0.01). Except for a group of bacteria unidentified by matrix-assisted laser desorption ionisation time-of-flight (MALDI-TOF) (p = 0.02), no apparent association was found between histopathologically diagnosed omphalitis and the prevalence of specific pathogens (p > 0.05). The frequency of histopathologically diagnosed omphalitis tended to increase with increasing age in both cases and controls. The frequency of piglets with both histopathological omphalitis and arthritis/synovitis was significantly different among cases and controls (p = 0.05). This was due to all controls, and none of the cases, with arthritis/synovitis presented histopathological omphalitis.

Conclusion: The clinical differentiation between omphalitis cases and controls did not correspond to the histological diagnosis of omphalitis in zero-to-three days old piglets. An inaccurate clinical diagnosis complicates prudent use of antimicrobials in pig herds. In addition, animal welfare may be hampered in infected piglets due to lack of treatment and in healthy piglets due to the antimicrobial effect on the gut microbiome.