农林科学最新文献

Lactococcus petauri is an emerging bacterial pathogen associated with disease outbreaks in freshwater and marine fish species worldwide. While it has been increasingly reported in countries bordering the Mediterranean Sea, no official records of L. petauri have yet been made in Italy for saltwater species. This study reports, for the first time, the presence of L. petauri in European seabass (Dicentrarchus labrax) farmed in land-based tanks along the south-western coast of Italy, based on a retrospective analysis of previously isolated strains. Although only a single isolate was positive, the finding is of notable significance as it originated from a sample collected in 2012. This temporal aspect highlights the likelihood that L. petauri has been circulating in Italian aquaculture systems for at least a decade. The isolate also exhibited a broad antimicrobial resistance profile, including resistance to amoxicillin, fluoroquinolones and trimethoprim/sulfamethoxazole. The historical misidentification of L. petauri is linked to its clinical similarity with Lactococcus garvieae. This highlights the value of re-analysing archived strains with modern tools and underlines the need for accurate diagnostics in aquaculture. The detection in D. labrax extends the known host range and suggests a longer, undetected presence in the Mediterranean.

Decapod iridescent virus 1 (DIV1) causes severe disease outbreaks in shrimp and crab culture areas. A simple, rapid, and visual DIV1 assay is important for the control of viral diseases. This study presented a novel DIV1 detection method that combines recombinase polymerase amplification (RPA) and lateral flow strip (LFS). After selecting primers and probes, we optimised the concentration of the reverse primers, reaction time, as well as reaction temperature of RPA-LFS detection. RPA can amplify the target gene within 18 min at a constant temperature of 38°C, and LFS can observe the amplification results within 3 min. Importantly, there is no cross-reactivity with other infectable shrimp viruses and pathogens, such as WSSV, IHHNV, TSV, EHP, CMNV, YHV, MrNV samples, as well as Vp_AHPND. In addition, RPA-LFS has high detection sensitivity, with a lower detection limit of 1.12 × 10¹ copies/μL. Using 110 field samples, the results of qPCR recommended by WOAH (OIE) and RPA-LFS were identical, indicating that RPA-LFS is as reliable as qPCR. The RPA-LFS assay is a valuable tool for the rapid and accurate detection of DIV1.

This study reports the first detection of Babesia aktasi and Anaplasma phagocytophilum in a bezoar goat (Capra aegagrus), providing insight into the presence of these pathogens in wild caprinae. The infected goat exhibited a localised ocular infection but showed no clinical signs of acute piroplasmid or Anaplasma infections. Microscopic examination of blood smears revealed low parasitemia of intra- and extraerythrocytic piroplasms and intragranulocytic morulae, consistent with chronic infection. PCR and sequence analysis confirmed that the Babesia species detected was B. aktasi, a recently described piroplasmid previously reported in domestic goats. Phylogenetic analysis placed the B. aktasi haplotype within the Babesia sensu stricto clade, closely related to sequences from domestic goats in Türkiye and an uncharacterised Babesia sp. from a red deer. The A. phagocytophilum strain detected in this study belonged to ecotype 1, which includes human pathogenic strains. These findings raise the possibility that bezoar goats may contribute to the natural maintenance of B. aktasi and A. phagocytophilum, highlighting their potential involvement in the enzootic cycles of these pathogens alongside domestic caprinae. Given that bezoar goats are the ancestors of modern domestic goats and that their habitats overlap in Anatolia, further research is needed to better understand the transmission dynamics, vector associations and zoonotic potential of these pathogens.

The blowflies (Calliphoridae) represent a significant portion of schizophoran fly diversity, comprising approximately 2000 known species. Among them, the genus Calliphora Robineau-Desvoidy is one of the largest, with over 100 species primarily distributed in the Holarctic Region and Australasia. Blowflies include several ubiquitous species and are primarily recognised for their medical and veterinary importance. In the Afrotropics, Calliphora was previously known from only two species: the native Calliphora croceipalpis Jaennicke and the introduced Calliphora vicina Robineau-Desvoidy. Two new distinctive species of Calliphora collected during recent fieldwork in Ethiopia are described using methods of integrative taxonomy. Calliphora teraramma sp. n. is characterised by peculiar male genitalia, with large cerci and a minute phallus. Calliphora mesay sp. n. is characterised by morphological and molecular traits, a close relative of the cosmopolitan C. vicina. In addition, we developed a cytochrome c oxidase subunit I (COI) barcode reference library for Palaearctic and Afrotropical Calliphora species, including 33 newly generated barcodes. Molecular species delimitation analyses using the software Automatic Barcode Gap Discovery (ABGD) and Assemble Species by Automatic Partitioning (ASAP), implemented through the recently developed integrative platform Spart Explorer, largely support morphological species concepts.

Hippobosca equina, a common ectoparasite of horses, poses a significant challenge to equine health worldwide. This study provides a molecular characterization of H. equina and examines its impact on host immune responses and oxidative stress. Genetic analysis of samples from various regions revealed notable homogeneity, indicating limited genetic variation among populations. Phylogenetic analysis demonstrated close genetic relationships among sequences from Egypt, France, Kazakhstan and Portugal, while also showing comparable but more distant identities to sequences from China, Denmark, Finland and other countries. Infested horses exhibited elevated levels of pro-inflammatory cytokines, including IL-6, TNF-α and IFN-γ, relative to uninfested control horses, indicating a strong immune response to the parasite. Additionally, there was a significant increase in oxidative stress markers, including malondialdehyde, catalase, glutathione peroxidase and nitric oxide, indicating substantial cellular damage. These findings highlight the dual impact of H. equina infestations on horse health, prompting both immune activation and oxidative stress. This study emphasizes the importance of targeted pest management strategies that consider the genetic uniformity of parasites and host physiological responses. By providing valuable insights into the complex host-parasite interactions between H. equina and equine hosts, this research enhances our understanding of equine ectoparasites and suggests potential avenues for improving horse health and welfare.

Sedation is important for safe equine dental procedures, but it is unknown if there is a higher risk of sedation causing hypothermia in procedures performed during cold months. The authors hypothesize that sedation for a dental procedure will significantly decrease rectal body temperature in cold as compared to warm ambient temperatures. Adult equids (N = 246), from a private equine dentistry practice, that underwent dental equilibration, were selected for the study. Each horse's weight was estimated and sedation was administered intravenously (0.01 mg/kg detomidine and 0.01 mg/kg butorphanol) and intramuscularly (0.5 mg/kg xylazine and 0.03 mg/kg acepromazine). Ambient and serial rectal temperatures (presedation [PRE], 15 min after initial intravenous sedation [POST15], and at the end of the procedure [END]) were recorded. Statistics included Shapiro-Wilks test, Spearman's correlation coefficient, and a Friedman test with Dunn's posthoc test (significant at P < .05). Ambient temperatures ranged from -7.8 °C to 30 °C. The median (95% confidence interval) rectal temperature was PRE: 37.4 (37.2 °C-37.7 °C), POST15: 37.5 (37.2 °C-37.8 °C), and END: 37.4 (37.1 °C-37.7 °C). POST15 temperatures were significantly increased from PRE (P = .001) to END (P = .005) temperatures. PRE to END temperatures were not significantly different (P > .9). There was a weak positive correlation between ambient and POST15 temperatures (rho = .26, P < .001) and END temperatures (rho = .25, P < .001). Seven animals became hypothermic (<36 °C), only 2 at ambient temperatures below 4.44 °C. Rectal body temperature in equids after sedation at ambient temperatures between -7 °C and 30 °C remains at a safe level in most instances, suggesting dental procedures can be performed under sedation during cold weather.

Atypical porcine pestivirus (APPV) is responsible for congenital tremor (CT) type A-II in pigs, a globally distributed neurological disease, with many unresolved questions regarding its pathogenesis and pathology. This descriptive case-control study assessed the viral load of APPV and its association with lesions in the central nervous system (CNS), as piglets born with severe clinical signs of CT recovered from clinical disease. The virus was found in all pigs with CT across 3 age groups (newborn, 3-week-old, 4- to 5-month-old CT pigs) using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The highest viral load was observed in the spinal cord of newborns and in the cerebellum of older groups. No APPV was detected in control pigs. Histologic evaluation revealed variable vacuolization in the CNS white matter of CT-affected pigs, which was most prominent in the spinal cord, cerebellum, and cerebrum of newborns, and in the cerebellum and cerebrum of 3-week-old pigs. Transmission electron microscopy demonstrated hypomyelination in newborn and 3-week-old CT pigs, but myelin levels comparable to those of control pigs in 4- to 5-month-old CT pigs. This research demonstrates the prolonged presence of APPV in the CNS of pigs born with severe signs of CT. Variable white matter vacuolization and hypomyelination can be found up to 3 weeks of age, but myelin levels normalize in older pigs, suggesting a delayed myelination process. Further research is needed to confirm the primary cellular target for APPV in the CNS and to understand how the virus affects the myelination process.

Neoplasia is rarely reported in European hedgehogs (Erinaceus europaeus). A retrospective search was conducted by contacting multiple veterinary diagnostic laboratories for cases of lymphoma in European hedgehogs. This resulted in 5 cases, from which clinical, gross, histologic, and immunophenotyping findings were recorded. Most animals (3/5) had skin masses involving the cervical region, 1 hedgehog had dyspnea and lethargy associated with hydrothorax, whereas another exhibited icterus and lethargy. The primary site of the lymphoma was the skin, particularly the neck or head (3/5), the thymus (1/5), and multicentric (1/5). Immunophenotyping confirmed B-cell lymphoma in 2 skin cases, a T-cell lineage for the thymic and multicentric cases, and undetermined for the remaining skin lymphoma. CD3, PAX5, and CD79a were reliable immunohistochemistry markers in formalin-fixed tissues in European hedgehogs. Although uncommon, lymphoma should be considered in the differential diagnosis for adult European hedgehogs with skin nodules, especially those seeming to originate from the neck.

Renal oxalosis has been reported in New and Old-World monkeys. Occasional reports describe a low prevalence of subclinical renal oxalosis, but these typically lack supporting evidence of primary oxalosis or toxicity and may be a natural background lesion. In a retrospective cross-sectional postmortem observation study, 12 of 156 (7.7%) African green monkeys (AGMs) (Chlorocebus sabaeus) from the Behavioural Science Foundation (St. Kitts) colony had histological evidence of oxalate-induced nephrosis (renal oxalosis). Histologically, affected tubules from both the cortex and medulla were ectatic; expanded several times normal size; and lined by attenuated, degenerative, regenerative, or necrotic epithelium with intraluminal, pale yellow, translucent, variably shaped, crystals that were birefringent under polarized light (calcium oxalate). The tubules were often surrounded by multinucleated macrophages. To identify independent predictors of renal oxalosis, we fit a multivariable logistic regression model with robust ("sandwich") standard errors, including sex, age, and birth origin, as categorical covariates. Several enrichment food items were found to be oxalate-rich: sweet potato (95.9 mg/100 g), pumpkin (64.6 mg/100 g), and bananas (169 mg/100 g). There was a significant increase in the prevalence of calcium oxalate concretions with age, from 0% in young monkeys to 18.6% in aged individuals, likely due to longer exposure to oxalate-rich produce and a cumulative effect. Due to the large ingestion of oxalate-rich foods, diet is suspected to be a major cause of subclinical oxalosis in the St. Kitts AGM, raising awareness of this potential background finding during their use as laboratory animals in toxicologic and other research studies.

Hepatic hemosiderosis has not been systematically studied in African green monkeys (Chlorocebus sabaeus). We aimed to determine the prevalence of histologic hepatic hemosiderosis in this species, demographic predictors of its presence and severity, and the quantitative relationship between histological grade and hepatic iron concentration. We evaluated liver samples of 155 African green monkeys from a research colony in St. Kitts (24 juveniles, 89 adults, 42 geriatrics) using histology (hematoxylin and eosin, Perls Prussian blue) to semiquantitatively grade (0-4) hemosiderin deposits. Quantitative hepatic iron was measured via coupled plasma mass spectrometry in 146 samples. Overall, 63.9% (99/155; P < .001 vs 50%) exhibited histological hemosiderin deposits. The grade distribution was 52 (33.5%) grade 0, 29 (18.7%) grade 1, 23 (14.8%) grade 2, 25 (16.1%) grade 3, and 26 (16.8%) grade 4. Wild-caught origin was protective (odds ratio (OR) = 0.10, 95% confidence interval (CI) = 0.04-0.29, P < .001), while geriatric age was associated with iron accumulation (OR = 8.92, 95% CI = 2.06-10.61, P = .003). Ordinal regression confirmed lower odds of higher grades in wild-caught (OR = 0.095, 95% CI = 0.047-0.193, P < .001) and higher odds of higher grades in adult monkeys (OR = 4.2, 95% CI = 1.43-12.35, P = .009). Trend tests (z = 9.81, P < .0001) and Spearman's ρ = 0.82 (P < .0001) confirmed a strong association between pathology and iron burden. Recommended iron requirements may be excessive for certain life stages in this species. Colony-born and younger animals are at highest risk, while adult males show protection. Histological grading correlates strongly with quantitative iron measures, validating its use as a semiquantitative surrogate.