Veterinary Sciences最新文献

The cornea is essential for proper ocular function, yet its histological structure varies considerably among animal species. Of particular importance are the palisades of Vogt in the limbal region, as they serve as a niche for limbal epithelial stem cells involved in corneal epithelial regeneration. This study was conducted on 73 eyeballs collected from 18 species of non-human primates originating from the Wrocław Zoological Garden (Poland). Eyeballs were fixed, processed, and embedded in paraffin. Four-micrometer sections were stained with Mayer's H&E and PAS. Microscopically, the cornea showed either a four-layered pattern (anterior corneal epithelium, corneal stroma, Descemet's membrane, posterior corneal epithelium) or a five-layered pattern when Bowman's layer was present. A four-layered cornea occurred in the ring-tailed lemur, gray mouse lemur, Guianan squirrel monkey, Angolan colobus, and L'Hoest's monkey, while the remaining species showed a five-layered structure with Bowman's layer. The anterior corneal epithelium varied between species in thickness and number of cell layers (central region: 2-3 to 10-15 layers; 11.81 ± 0.43 µm to 44.23 ± 0.69 µm; peripheral region: 4-5 to 9-11 layers; 8.63 ± 2.57 µm to 42.45 ± 8.61 µm). Bowman's layer ranged from 1.18 ± 0.01 µm to 3.22 ± 0.05 µm. The corneal stroma thickness differed markedly (237.96 ± 9.64 µm to 1438.29 ± 16.38 µm), as did Descemet's membrane (4.92 ± 0.20 µm to 43.45 ± 0.49 µm), along with PAS reaction intensity. In the limbus, palisades of Vogt ranged from weakly to clearly developed; well-defined crypt-like structures were observed in the red-bellied lemur, red ruffed lemur, black-and-white ruffed lemur, Guianan squirrel monkey, L'Hoest's monkey, Celebes crested macaque, and yellow baboon. The limbal epithelium also varied in thickness (5-6 to 15-17 cell layers). These results confirm distinct species-specific differences in corneal and limbal morphology that may reflect ecological conditions and functional adaptation. The presented data provides a comparative reference for veterinary ophthalmology and for studies on corneal epithelial regeneration involving limbal stem cells.

In Australian Cattle Dogs (AUCDs), cystinuria was reported to be an autosomal dominant trait caused by a 6 bp deletion in the SLC3A1 gene (type II-A). Here we report an androgen association in this breed. A family of 11 adult AUCDs (five intact and one neutered male and five females) was genotyped for the SLC3A1 c.1095_1100del variant, and urine was examined for concentrations of cystine, ornithine, lysine, and arginine (COLA). Among this family, three males and five females tested heterozygous for the mutation, while all other AUCDs were homozygous for the wild-type allele. The two heterozygous intact males had severe COLA-uria, which decreased markedly after castration. Neither the third heterozygous male with a history of cystine calculi but already castrated nor the five heterozygous females exhibited increased COLA-uria. Heterozygosity for the 6 bp deletion in the SLC3A1 gene was associated with cystinuria in intact male AUCDs, but not in females. Castration of the heterozygous males reduced the cystinuria. Either the type II-A cystinuria in the AUCDs is an androgen-associated dominant trait, or this family also has another type III (androgen-dependent) cystinuria. Larger surveys are needed to further define the type(s) of cystinuria and effects of castration in AUCDs.

In this study, a multienzyme isothermal and lateral flow dipstick combination assay for PPRV detection was established, the designed primers and probes targeting the N gene were screened and optimized, and analytical sensitivity, specificity, and repeatability of developed method were systematically evaluated. The experimental results demonstrated that this method is easy to operate, can complete detection within 30 min at 42 °C, and is capable of detecting all lineages of peste des petits ruminants virus (PPRV) without cross-reactivity with other viruses. The limit of detection could reach 10 copies/μL. Repeatability validation showed that the coefficients of variation (CV) for both intra-assay and inter-assay experiments were below 3.0%. The positive detection rate for clinical samples could reach 100%. The test results are visually interpretable via fluorescence and lateral flow strips. In conclusion, this method exhibits high analytical sensitivity, specificity, and excellent repeatability, enabling rapid diagnosis of peste des petits ruminants (PPR).

This experiment aimed to investigate the effects of replacing alfalfa hay with Glycyrrhiza stem and leaf silage (moisture content: 45%) on rumen in vitro fermentation parameters, nutrient digestibility, and dynamic changes of microbial community composition. In vitro fermentation was conducted with 0% (control group G0A100), 50% (G50A50), and 100% (G100A0) alfalfa hay replaced by semi-dry silage of Glycyrrhiza stems and leaves with 45% moisture content for 72 h. Cumulative gas production (GP), fermentation parameters, microbial community composition at different time points, and post-fermentation nutrient digestibility were determined, with comprehensive evaluation by principal component analysis (PCA) and gray relational analysis (GRA). Results showed that GP of G50A50 and G100A0 was significantly higher than G0A100 at 3 h (p < 0.05), and that of G50A50 was significantly higher than the other two groups at 24 h (p < 0.05). pH of G50A50 was significantly lower than the other two groups at 3 h (p < 0.05). In vitro dry matter digestibility (IVDMD) at 24 h and 72 h, in vitro neutral detergent fiber digestibility (IVNDFD) at 12 h, and in vitro acid detergent fiber digestibility (IVADFD) at 12, 24 and 72 h of G0A100 and G50A50 were significantly higher than G100A0 (p < 0.05). PCA comprehensive scores ranked as G0A100 (0.170) > G50A50 (0.141) > G100A0 (-0.311). GRA comprehensive scores ranked as G50A50 (0.792) > G0A100 (0.756) > G100A0 (0.681). LEfSe analysis indicated distinct microbial biomarkers at 72 h, and KEGG functional profiles were highly consistent among groups. Under the experimental conditions, 50% Glycyrrhiza stem and leaf silage is recommended to replace alfalfa hay in dairy cow diets.

Salinity stress represents a critical environmental constraint that significantly limits the development of tilapia aquaculture in brackish water environments. Its substantial impacts on fundamental physiological processes in fish, particularly osmotic balance, energy metabolism, and antioxidant defense mechanisms, have become a major scientific concern in aquaculture research. To systematically elucidate the molecular mechanisms underlying the response of genetically improved farmed tilapia (Oreochromis niloticus) to salinity stress and to test the hypothesis that it adapts through metabolic reprogramming for energy reallocation under such conditions, this study employed an integrated transcriptomic and metabolomic approach. Through a rigorously controlled experimental design with freshwater (0‱) as the control group and brackish water (24‱) as the experimental group, we conducted a comprehensive analysis of dynamic changes in gene expression profiles and metabolite spectra in the liver tissues of experimental fish. The study yielded the following key findings: First, salinity stress significantly suppressed growth performance indicators, including body weight and length, while simultaneously inducing extensive transcriptomic restructuring and profound metabolic remodeling in liver tissue. A total of 1529 differentially expressed genes (including 399 up-regulated and 1130 down-regulated genes) and 127 significantly differential metabolites were identified. Second, the organism achieved strategic reallocation of energy resources through coordinated suppression of multiple energy-consuming anabolic pathways, particularly steroid biosynthesis and fatty acid metabolism, with the remarkable down-regulation of Fasn, a key gene in the fatty acid synthesis pathway, being especially prominent. Energy-sensing and metabolic homeostasis regulatory networks played a central coordinating role in this process, guiding the organism through metabolic reprogramming by regulating downstream metabolic nodes. From a multi-omics integrative perspective, this study provides in-depth insights into the sophisticated metabolic remodeling and energy allocation strategies employed by GIFT to cope with salinity stress. These findings, particularly the suppression of fatty acid biosynthesis and the reprogramming of glycolysis/gluconeogenesis pathways, not only elucidate the molecular mechanisms by which teleosts achieve environmental adaptation through energy reallocation, but also provide actionable molecular targets for the selective breeding of salinity-resilient tilapia strains.

Gastrointestinal nematodes (GIN) represent a major constraint to sheep production, and sustainable alternatives to routine anthelmintic use are increasingly required. This study compared two parasite control strategies in Zerasca sheep: routine albendazole treatment administered twice yearly (T) and a long-term non-chemical approach based on rotational grazing (relocation to a new pasture when grass height fell below 10 cm) combined with quarterly veterinary monitoring (NT). Twenty-four adult ewes (n = 12 per group) were monitored over an eight-month period. Mean faecal egg counts (EPG) differed significantly between groups (T: 210 ± 78; NT: 529 ± 89; p = 0.0007). In group T, EPG values decreased markedly 7 days after treatment but increased again by 150 days, resulting in no persistent differences between groups over time. Despite higher parasite burdens, NT sheep showed significantly higher body condition scores compared with treated animals (3.00 ± 0.61 vs. 2.51 ± 0.53; p = 0.0014). Haematological parameters were largely comparable between groups, although mild reductions in RBC, HGB, and HCT were observed in both. Treated sheep exhibited higher AST activity (p < 0.0001) and transient increases in ALT and BUN following treatment. Hair cortisol concentrations did not differ significantly between groups. Overall, these findings suggest that a non-chemical parasite management strategy, when combined with controlled grazing and veterinary monitoring, may maintain acceptable parasite levels while supporting body condition and stable welfare indicators, potentially reducing reliance on routine anthelmintic treatments.

Animal-derived E. faecium poses a public health risk due to its capacity to acquire antimicrobial resistance (AMR) and virulence genes. However, the pathogenicity and cross-host transmission potential of strains originating from unique environments, such as the Qinghai-Tibet Plateau, remain poorly understood. In this study, a strain of E. faecium was isolated from yak feces. We constructed a phylogenetic tree and identified AMR and virulence genes via whole-genome sequencing. Antimicrobial susceptibility testing was performed to determine its resistance phenotype. An in vivo mouse infection model was established to assess pathogenicity, and transcriptomic analysis was utilized to investigate the host's molecular response mechanisms in infected intestinal tissue. The results indicated that this yak-derived strain is closely related to human clinical isolates, suggesting a risk of cross-host transmission. The strain harbored the AMR genes AAC(6')-Ii, msrC, and eatAv and exhibited resistance to penicillin, kanamycin, erythromycin, and clindamycin. The strain harbored key virulence genes, such as bopD, Acm, and ClpP. Infection with this strain caused characteristic inflammatory damage in mouse intestinal tissue, as revealed by histopathological examination, including epithelial necrosis, vascular congestion, and inflammatory cell infiltration. Transcriptomics further delineated a complete "Recognition-Response-Damage" signaling axis: pathogen recognition through Toll-like receptors and NOD-like receptors activates the NF-κB and MAPK signaling pathways. This activation is accompanied by significant upregulation of various inflammatory factors and recruits immune cells via chemokine signaling, ultimately leading to tissue damage. Our findings provide insights into the pathogenic pathway of this strain from genetic determinants to phenotypic manifestations, providing a theoretical foundation for assessing the public health risk posed by animal-derived E. faecium and for developing targeted intervention strategies.

Severe crusting dermatosis affecting the mucocutaneous junctions, pressure points, and trunk of dogs fed low-quality dry food was first reported in the United States in the 1980s. Since then, only a few cases have been documented. Twenty-two adult dogs owned by private individuals were evaluated. All dogs exhibited thick crusts forming plaques and marked scaling on the face-particularly around the lips, nasal bridge, and eyelids-as well as on the paw pads, dorsal digits, abdomen, and dorsum. Pruritus ranged from moderate to severe, and all dogs showed varying degrees of lethargy and reduced activity. Each dog was fed a low-quality commercial diet. A presumptive diagnosis of dermatosis associated with poor-quality food was made. Skin biopsies from nine dogs revealed similar histopathologic changes, characterized by epidermal hyperplasia, severe parakeratotic hyperkeratosis with spongiosis, and exocytosis of lymphocytes and neutrophils. The skin lesions resolved within 15-30 days after switching to a high-quality diet. This case series highlights that dermatosis associated with low-quality food should remain in the differential diagnosis for dogs presenting with symmetric crusted and scaly lesions on the face, mucocutaneous junctions, and paws, particularly when nutritional deficiencies are suspected.

Skin development undergoes significant molecular changes during early life stages in mammals. This study investigated transcriptomic differences in skin tissues between newborn (Y0) and one-year-old (Y1) Dezhou donkey foals using RNA-sequencing technology. Skin samples were collected from 13 Dezhou donkeys (7 newborns and 6 one-year-olds) and subjected to transcriptome analysis using the Illumina NovaSeq 6000 platform. A total of 133.66 Gb of clean data was obtained, yielding 252,342 transcripts and 204,683 unigenes. Differential expression analysis revealed 9878 significantly differentially expressed genes (DEGs) between age groups, with 4252 up-regulated and 5626 down-regulated genes in Y1 compared to Y0. Functional enrichment analysis identified key pathways, including ECM-receptor interaction, PI3K-Akt signaling, WNT signaling, and TGF-β signaling pathways. Notable findings included up-regulation of keratin genes (KRT1) and WNT family genes (WNT3, WNT4, WNT5, WNT6, WNT7, WNT10) in one-year-old foals, while collagen genes (COL1A, COL4A, COL5AS) and TGF-β signaling components (TGFB2, TGFB3, BMP5) were down-regulated. These results suggest that skin maturation involves enhanced barrier function, hair follicle development, and reduced collagen synthesis rates, providing insights into mammalian skin development mechanisms and potential applications in veterinary medicine and comparative biology.

Intestinal emphysema is a rare pathological condition observed in humans and animals, characterized by the presence of multiple gas-filled cysts within the intestinal wall. In pigs, it is occasionally observed at slaughter, without affecting carcass suitability for human consumption or impairing farm profitability. Despite investigations, the etiology and pathogenesis of intestinal emphysema remain poorly understood. Therefore, this study aimed to provide further morphological insights into porcine intestinal emphysema through histopathological, histochemical and immunohistochemical methods. A total of ten slaughtered heavy pigs were examined, showing gross lesions consistent with intestinal emphysema. Gaseous cysts were predominantly located in the submucosal and mesenteric layers, at least partially lined by lymphatic endothelial cells. The cysts were separated by fibrous connective septa and were almost invariably associated with granulomas, consisting of epithelioid macrophages and multinucleated giant cells. Overall, the immunohistochemical patterns of porcine intestinal emphysema overlap with those described in humans and support the hypothesis that lesions likely originate within the lymphatic vessels.