Veterinary Research Communications最新文献

Canine leptospirosis is a public health concern due to its zoonotic potential, as infected dogs may act as asymptomatic carriers and shed Leptospira without showing clinical manifestations. The epidemiological boundaries of leptospirosis become blurred in areas where environmental and socio-economic conditions favor pathogen persistence and transmission. A preliminary epidemiological survey was conducted to detect Leptospira DNA in dogs in Soledad municipality, characterized by poverty, unplanned urban growth, limited sanitation services, and recurrent flooding, to estimate infection frequency and assess their potential role as Leptospira carriers. A descriptive, cross-sectional study was performed in dogs. DNA was extracted from blood and urine samples and analyzed by PCR targeting the 16S rRNA (rrs) and lipL32 genes. Sequences generated were compared through BLASTn. Only the rrs sequences underwent phylogenetic analysis. A total of 154 dogs were enrolled. Sixteen breeds were represented, with mixed-breed predominating (43.50%; 67/154). Overall, infection rate was 9.1% (14/154). Based on rrs and lipL32 sequence identity, and rrs phylogeny, all positive samples were associated with pathogenic Leptospira, most closely related to Leptospira interrogans. Of these, 7.14% (11/154) showed renal shedding, compatible with chronic carriage, while 1.95% (3/154) tested positive in blood, suggesting recent infection. Our findings underscore the need to consider dogs as potential chronic carriers and support the integration of preventive measures into public health programs to reduce transmission risk in the municipality and northern Colombia.

The hybrid marbled goby (Oxyeleotris marmoratus ♀ × Oxyeleotris lineolatus ♂) is a high-value aquaculture species in China, with rapidly increasing production in recent years. While Streptococcus agalactiae is a well-known pathogen in various fish species, its association with marbled goby has not been previously reported. Here, we present the first confirmed case of S. agalactiae infection in farmed hybrid marbled goby. Infected fish exhibited typical signs of streptococcosis, including erratic swimming, hemorrhages at fin bases, skin ulcers, and cloudy or hemorrhagic eyes. A Gram-positive bacterial strain, designated ZH2208, was isolated from diseased fish. Morphological, biochemical, 16 S rRNA sequencing, and phylogenetic analyses identified the isolate as S. agalactiae, serotype Ia-a dominant serotype previously associated with tilapia infections in Guangdong, China. Challenge experiments using doses of 1 × 10⁴ and 1 × 10⁷ CFU/fish confirmed the high virulence of ZH2208, resulting in 50% and 100% mortality, respectively. Eleven virulence genes involved in host invasion, hemolysis, immune evasion, and blood-brain barrier penetration were detected by PCR. Histopathology revealed typical lesions in gills, liver, spleen, kidney, and brain, including acute inflammation, hemorrhage, and neuronal degeneration. Notably, pronounced swim bladder swelling with distinct hemorrhagic spots was observed. Antibiotic susceptibility testing showed that ZH2208 was sensitive to enrofloxacin and doxycycline but resistant to several common aquaculture antibiotics, highlighting its multidrug-resistant profile. In conclusion, this study provides the first comprehensive characterization of S. agalactiae infection in hybrid marbled goby. These findings support the development of effective prevention and control strategies, including vaccination and rational antibiotic use, to manage streptococcal disease in goby aquaculture.

Light is a critical environmental regulator of biological function in poultry, significantly influence on physiology, behavior, growth, production, and reproduction. Beyond its role in vision, light acts as a potent zeitgeber that synchronize circadian rhythms, and modulate neuroendocrine signaling and metabolic pathways essential for health and welfare. This review systematically evaluates current evidence on the role of modulated light environments in poultry production systems. For this purpose, comprehensive literature search was conducted using PubMed, Web of Science, Scopus, and Google Scholar to retrieve peer-reviewed studies published between 2000 and 2025. Studies were selected based on predefined inclusion criteria focusing on light spectrum, intensity, photoperiod, and light source in relation to poultry physiology, behavior, performance, and reproduction, while studies involving non-avian models or insufficient methodological detail were excluded. Collectively, the reviewed evidence demonstrates that variations in light wavelength, intensity, and duration significantly regulate feed intake, stress physiology, immune competence, and locomotor activity, and overall flock health. Blue and green wavelengths are consistently linked with enhanced growth performance and muscle development, whereas red light preferentially stimulates reproductive activity via activation of the hypothalamic-pituitary-gonadal axis. Optimized lighting programs improve egg production, shell quality, and hatchability while reducing aggression, feather pecking, and other maladaptive behaviors. Furthermore, light modulation also influences melatonin secretion and thermal regulation, thereby strengthening resilience against environmental stress. Emerging precision-lighting technologies, particularly LED systems and dynamic photoperiod schedules, provides new opportunities to enhance productivity, animal welfare, and sustainability. However, response variability among species, genotypes, and management systems underscore the need for integrative approaches that combine photobiology with genetics, nutrition, and welfare science. This review highlight mechanistic insights, practical implications and future directions for designing precision lighting program for to achieve poultry production goals.

The aim of this study was to describe the ultrasonographic and computed tomographic findings of a rare case of an atypical lipoma located in the abdominal cavity of a 13-year-old neutered male Schnauzer weighing 10.3 kg. The animal had a history of dyslipidemia and hypothyroidism, and, due to this clinical background, additional diagnostic tests were requested. On B-mode ultrasonography, an amorphous, hyperechoic, and homogeneous structure with well-defined borders was visualized in the mid-abdominal region, measuring approximately 10.3 cm in length and 6.8 cm in height. Subsequently, interventional ultrasonography was performed to obtain a guided sample. Because of the difficulty in delineating and evaluating adjacent organs, the animal was referred for computed tomography, which identified a well-defined expansile mass with smooth margins and homogeneous density, exhibiting attenuation values consistent with adipose tissue. The integration of imaging modalities, combined with image-guided sampling, proved essential for complementing the clinical assessment and guiding the diagnostic process.

The spore-forming bacterium Paenibacillus larvae causes a devastating brood disease of honey bees (Apis mellifera) named American foulbrood (AFB). It occurs worldwide and can lead to the death of whole colonies. Presence and prevalence of this pathogen in Palestine were unknown. Therefore, for two consecutive years, a field survey was conducted to screen Palestinian beekeeping locations for P. larvae. Honey samples were collected from 10 colonies each of eight apiaries throughout the West Bank in spring, summer, and fall. The presence of the bacterium was identified microbiologically, via PCR and DNA sequencing. Bacterial genotypes were analysed by repetitive element-PCR fingerprinting using ERIC primers. We unexpectedly detected spores in 87.5% of the inspected apiaries, 22.3% of 130 inspected colonies contained spores. 62.1% of the colonies with spores were lost during the study period. Whereas clinical symptoms of the disease were absent, parameters like reduced brood production and or spotty brood pattern proved to be helpful but indirect indicators for the disease. The detection of P. larvae is the first record of this fatal pathogen in Palestine. The genotype ERIC I was found six apiaries, the more virulent ERIC II genotype was present in two apiaries and is the first report of ERIC genotypes in Palestine. The study emphasizes the need for immediate steps toward efficient treatment limiting the spread of this harmful bacterium within the country and in neighboring countries.

A Loop-Mediated Isothermal Amplification (LAMP) assay coupled with Nucleic-acid Lateral Flow Immunoassay (NALFIA) was developed to differentiate B. abortus S19, the vaccine strain, from other Brucella Species, including wild-type B. abortus. LAMP assay was carried out by targeting the eryC gene, which is absent in B. abortus S19. Specific ligands on the test and control lines of the LFA strip were spotted. The presence of a colored band only on the control line indicated the presence of B. abortus S19. In contrast, a colored line on both test and control lines indicated the presence of other Brucella Species. The assay was found to be very specific, as it did not cross-react with any other bacterial genera. The assay was found to be very sensitive, and the limit of detection was found to be 1.76 pg of genomic DNA of bacteria. In spiked milk samples, the assay could detect 2.89 × 10³ CFU of bacteria. Thus, the assay, which has discriminatory power in the detection of B. abortus S19 and other Brucella Species, can be used as nucleic acid-based DIVA in clinical samples of suspected cases of bovine brucellosis, which can be a potential source of transmission in both humans and animals.

This study investigated the toxicological effects of chronic cadmium (Cd) exposure (0, 100, 300, and 500 μg/L for 28 days) on juvenile crucian carp (Carassius auratus), assessing impacts on gill tissue and gut microbiota using a multi-faceted approach. Histological analysis revealed concentration-dependent gill damage, including severe lamellar fusion and desquamation, with a parallel increase in apoptotic cells confirmed by TUNEL staining. Biochemically, Cd induced significant oxidative stress, as shown by decreased superoxide dismutase (SOD) activity, lowered levels of reduced glutathione (GSH) and total antioxidant capacity (T-AOC), and elevated malondialdehyde (MDA), a marker of lipid peroxidation. Gene expression analysis confirmed the activation of endoplasmic reticulum (ER) stress and pro-apoptotic pathways, with upregulation of chop and bax and downregulation of bcl2. Furthermore, Cd exposure profoundly restructured the gut microbiota, leading to pronounced dysbiosis and loss of microbial homeostasis. Collectively, these findings demonstrate that chronic Cd exposure induces gill damage in juvenile C. auratus through interconnected oxidative stress, ER stress, and apoptosis, while concurrently causing significant disruption to the intestinal microbial ecosystem.

Eucoleus garfiai is a parasitic nematode that infects the tongue epithelium of both wild and domestic suids. Despite reports from several countries, data concerning its molecular characterisation and true prevalence remain limited because detection often relies on less sensitive methods. One hundred wild boar tongues were collected from the Central Black Sea Region of Türkiye. Each tongue was divided into three sections, and the epithelial layer was meticulously examined under a stereomicroscope for parasites. Morphological identification was performed using light microscopy. Morphometric data were obtained from 209 male and 697 female specimens. Molecular confirmation was achieved by PCR amplification and sequencing of the 18 S rRNA gene of representatives from three provinces. The overall prevalence was 83% (83/100), the highest reported prevalence globally. A total of 906 parasites were collected, with a mean intensity of 10.9 parasites per infected host. The parasites were located exclusively in the anterior (62.4%) and middle (37.6%) thirds of the tongue. The morphological and morphometric features were consistent with previous descriptions of E. garfiai. Histopathological analysis revealed the presence of hyperkeratosis, parakeratosis, and a mild inflammatory infiltrate. Phylogenetic analysis of the 18 S rRNA sequences (deposited in GenBank under accession numbers PV111295, PV111296, PV111297) confirmed the identity of the isolates and revealed a distinct Turkish genotype. The prevalence of the condition was significantly higher in animals older than four years. This study reports the highest prevalence of E. garfiai to date, which is attributed to the use of a highly sensitive detection method. This study provides the first molecular characterisation and phylogenetic analysis of the parasite from Türkiye, confirming its presence with confidence. These findings underscore the necessity for refined diagnostic techniques in epidemiological studies and lay the foundation for future research on the parasite's biogeography.