农林科学最新文献

Duck plague, caused by a highly contagious α-herpesvirus, poses a major threat to waterfowl farming. Although UL50 homologs have been studied in mammalian α-herpesviruses such as HSV-1 and PRV, their role in avian herpesviruses remains unknown. Here, we investigated the function of the DEV UL50 gene, which encodes a conserved viral dUTPase, using bioinformatics, molecular biology, and virological approaches. Sequence analysis confirmed that DEV UL50 retains conserved catalytic motifs and structural features characteristic of α-herpesvirus homologs. A UL50-deleted mutant (ΔUL50) was constructed using the Red recombination system. In vitro, ΔUL50 exhibited reduced replication efficiency in DEFs, characterized by smaller plaques and lower viral titers, although overall growth kinetics were broadly similar to the WT. Notably, in duck DRG neurons, ΔUL50 replication was nearly abolished. GFP-reporter BAC viruses further confirmed that ΔUL50 failed to spread in DRG neurons but retained propagation in DEFs, indicating a cell-type-dependent replication defect. In vivo, ΔUL50 displayed markedly reduced viral loads and attenuated virulence, with no mortality and milder clinical and histopathological changes. These findings demonstrate that UL50 is dispensable but replication-supportive, particularly in non-dividing neuronal cells, highlighting its role in DEV pathogenicity and extending understanding of α-herpesvirus biology beyond mammalian systems.

Current vaccines against paratuberculosis offer incomplete and variable protection that raises questions on the ruminant immune responses to Mycobacterium avium subspecies paratuberculosis (Map) infection, particularly at the mucosal level. Thus, this study examined the immune responses established in the jejunum of goats vaccinated with oral, intradermal, or subcutaneous inactivated vaccines 11 months post-vaccination and 10 months after experimental Map challenge. In general terms, the mucosal response of non-challenged animals was not affected by vaccination. However, the quantification of immune cell populations, cytokine expression, recall responses of tissue-isolated mononuclear leukocytes, and secretory IgA levels in vaccinated and challenged animals with focal lesions suggested a local Th1 polarization. In contrast, those with diffuse lesions exhibited features compatible with the early development of a more Th2-biased response. The vaccination route played a lesser role in the immune response than lesion severity. Orally vaccinated and challenged goats, showed reduced local IL-1β and IL-17A expression, which may explain the milder lesions observed in these animals, despite their high bacterial burden, as these cytokines participate in macrophage recruitment, granuloma formation, and bacterial clearance. Nevertheless, owing to the high variability among challenged animals, larger sample sizes would allow robust conclusions to be drawn in further studies.

Equine squamous cell carcinomas (eSCCs) are common, and a proportion are likely induced by Equus caballus papillomavirus 2 (EcPV-2). Accurate prediction of clinical outcomes is challenging with no recognized prognostic criteria or consistent histopathological classification scheme for eSCC. The aims of this study were to histopathologically subtype a large case series of eSCCs (genital and ocular) and correlate them with p16 and HER-2 expression, equine papillomavirus infection status, and various clinical and histopathological parameters to predict tumour behavior and prognosis. One hundred and eighty-five samples were examined and subtyped histologically. HER-2 and p16 immunohistochemistry (IHC) and in situ hybridization (ISH) for the EcPV-2 E6/E7 oncogenes were performed on a subset of cases, and follow-up survival data were analyzed. The results were compared and correlated with published guidelines on the categorization of human SCC. Six histopathological subtypes of SCC, according to the WHO, were identified for the first time in horses: usual/invasive (most common), verrucous, pseudoglandular, papillary, warty, and basaloid, with different histological subtypes demonstrating prognostic significance. HER-2 and EcPV-2 statuses were not associated with prognosis in horses with SCC. p16 expression is not associated with EcPV-2 status but could be a potential prognostic factor. ISH demonstrated EcPV-2 genetic material in the majority of eSCCs, except for the papillary subtype, which includes mature, not just pre-cancerous, eSCCs. Widespread HER-2 expression in eSCCs could suggest a role for this cell receptor as a potential therapeutic target.

The use of artificial intelligence has been a revolution in human medicine in the last years. Machine learning (ML), a subset of artificial intelligence, has allowed the use of a large amount of data to search for associations of clinical significance. Although the use of ML with laboratory biomarkers in veterinary medicine is limited in comparison with the human side, the number of studies published in this field is increasing in recent years. This review addresses some basic concepts and gives a general overview of the use of ML in the area of biomarkers in veterinary medicine. It is especially focused on two species of each companion (dogs and cats) and farm (bovine and porcine) animals, and provides information about the advances made in the last years, indicating how ML using laboratory data can contribute to the diagnosis and monitoring of selected diseases and, in case of farm animals, also to better control and improve their productive performance. In addition, possible new applications such as optimizing laboratory management, refining diagnostics or improving treatment monitoring based on the experience in humans are outlined. This narrative review can contribute to a better knowledge about the possible use of ML in laboratory biomarkers in veterinary and animal sciences for current and future applications.

AIM (apoptosis inhibitor of macrophage), also known as CD5L, is a macrophage-derived scavenger protein with broad immunomodulatory roles in mammals. Secreted by tissue macrophages, AIM circulates bound to IgM pentamers, which stabilize the protein in blood; free AIM is released during inflammation to influence immune signaling and cellular homeostasis. (Yang et al. 2023). In cats, AIM exhibits distinctive structural and biochemical properties, existing as both a three-domain (37 kDa) and a four-domain (45 kDa) variant generated through exon 3 duplication (Evangelista et al. 2025), and binding IgM approximately 1000-fold more tightly than murine AIM due to a species-specific positively charged cluster in its third SRCR domain (Miyazaki et al., 2018). These differences suggest feline AIM may function distinctly from human/mouse AIM. Feline injection-site sarcomas (FISS) arise in the context of chronic inflammation and frequently contain abundant tumor-associated macrophages (TAMs)associated with tumor aggressiveness and progression (Gomes et al., 2025). Given AIM's macrophage origin and its established roles in inflammatory regulation, autophagy signaling, and complement-mediated tumor targeting, we propose a directional hypothesis: that the high-affinity IgM-binding of feline AIM constrains free AIM availability in vivo, shifting the functional balance away from complement-mediated tumor cytotoxicity and toward macrophage-intrinsic M2-polarizing pathways, thereby promoting an immunosuppressive tumor microenvironment that contributes to FISS progression. Exploring AIM in this context may provide new perspectives for investigation in feline tumor immunology.

Long non-coding RNAs (lncRNAs) are involved in various regulatory processes during muscle development. Our previous RNA-seq study identified LNC_003296 as being significantly differentially expressed between ovariectomized Small-tailed Han sheep (OR-STH) and their non-ovariectomized counterparts (STH). Through biotinylated RNA pull-down assays and RNA immunoprecipitation (RIP), we further demonstrated that LNC_003296 directly interacts with Hsp70. Protein stability and degradation experiments revealed that LNC_003296 enhances the protein stability of Hsp70. Overexpression of either LNC_003296 or Hsp70 promoted myoblast proliferation, facilitated differentiation, and contributed to skeletal muscle fiber formation. Conversely, their knockdown suppressed cell proliferation and inhibited differentiation. In summary, these data indicate that LNC_003296 can bind to Hsp70 and enhance its protein stability, thereby influencing the proliferation and differentiation of myoblasts.

Congestive heart failure (CHF) secondary to myxomatous mitral valve disease (MMVD) is managed with diuretics, yet the prognostic value of short-term hemodynamic responses remains unclear. This retrospective study evaluated 50 dogs with ACVIM stage C or D MMVD hospitalized for CHF. We assessed changes in body weight, echocardiographic parameters, and renal values before and after intravenous (IV) diuretic therapy to determine their association with survival. IV diuretic therapy led to significant reductions in body weight and echocardiographic indices, including the left atrium-to-aortic root ratio (LA/Ao), normalized left ventricular internal diameter in diastole (LVIDDN), and early diastolic transmitral flow velocity (all P < 0.005). Conversely, blood urea nitrogen and creatinine concentrations significantly increased (P < 0.001). However, neither short-term changes in these variables nor post-treatment values were associated with long-term survival. Baseline LA/Ao and LVIDDN were related to survival in univariable analysis, while prior oral diuretic therapy was the only independent predictor in the multivariable model (Hazard Ratio 4.21; P < 0.001). Dogs with prior diuretic use had shorter median survival (194 days) than those without (459 days). Thus, short-term echocardiographic improvements reflect effective decongestion rather than long-term prognosis. Prognostic evaluation should prioritize baseline assessments and treatment history.

Staphylococcus aureus (S. aureus) is a Gram-positive bacterium that serves as a major pathogen causing bovine mastitis. One of the key intracellular survival mechanisms of S. aureus involves the induction of autophagy. The capacity of S. aureus to subvert autophagy for intracellular survival and replication is strongly linked to its broad array of virulence determinants, which play pivotal roles in infection establishment and immune evasion. One of these virulence factors is phenol-soluble modulin alpha (PSMα), an amphipathic small peptide that plays a key role in the pathogenesis of S. aureus. Utilizing gene-edited S. aureus strain and bovine mammary epithelial cells (BMECs, MAC-T), this study elucidates the involvement of PSMα in autophagy induction during S. aureus infection. The results demonstrated that PSMα knockout attenuated S. aureus-induced autophagy, weakened the activation of the PI3K/Akt/mTOR pathway, and reduced intracellular bacterial load. Our findings elucidate a PSMα-dependent autophagy induction mechanism in S. aureus infection, which is associated with the intracellular survival of S. aureus.

Myxomatous mitral valve disease (MMVD) is leading cause of acquired heart failure in small-breed dogs. Although the American College of Veterinary Internal Medicine (ACVIM) staging is widely used in practice, how each stage and the degree of cardiac remodeling affect survival has not been clearly defined. We aimed to determine whether severe remodeling in dogs with preclinical (stage B2) disease is associated with survival differences compared with dogs with congestive heart failure (CHF; stage C) and less severe remodeling. This retrospective study analyzed 270 dogs with MMVD, stratified by the left atrium-to-aortic root ratio as having mild (<1.9), moderate (1.9-2.2), and severe (≥2.2) left atrial enlargement. Survival for dogs with stage B2 disease with severe LA enlargement did not differ significantly from dogs with stage C disease with mild-to-moderate enlargement. However, within the subgroup with severe LA enlargement, dogs that developed CHF had significantly shorter survival than those that remained in stage B2 (360 vs. 654 days; P = 0.032). Severe LA enlargement in dogs with preclinical disease contributes to a poor prognosis comparable to that of CHF with mild-to-moderate enlargement, indicating that stage alone may be insufficient for determining prognosis and that LA remodeling should also be considered.