Veterinary World最新文献

Background and aim: Haemonchus contortus is a highly pathogenic blood-feeding nematode of small ruminants, responsible for severe anemia, production losses, and mortality. Excessive use of synthetic anthelmintics, especially benzimidazoles, has led to widespread drug resistance, prompting a need for alternative therapeutics. Nicotiana tabacum (tobacco) contains bioactive alkaloids such as nicotine, which target nematode acetylcholine receptors and may provide sustainable parasite control. This study aimed to isolate, characterize, and evaluate the in vitro and in vivo anthelmintic efficacy and safety of alkaloid-rich fractions of N. tabacum against benzimidazole-resistant H. contortus in goats, in line with the One Health approach and the United Nations Sustainable Development Goals (SDGs 2, 3, 12, and 15).

Materials and methods: Leaves of N. tabacum were authenticated and subjected to sequential solvent extraction. Alkaloid fractions were confirmed by TLC and HPLC. In vitro assays, including adult motility and egg hatch tests, were conducted at concentrations of 1-5 mg/mL against resistant H. contortus isolates. The most active fraction (ethyl acetate) was administered orally in naturally infected Beetal goats (n = 25) at low (0.8 mg/kg), medium (1.2 mg/kg), and high (1.6 mg/kg) doses for 14 days, alongside negative (saline) and positive (oxfendazole 4.5 mg/kg) controls. Fecal egg counts, hematology, and liver enzyme levels were analyzed to determine efficacy and safety.

Results: The ethyl acetate fraction exhibited complete (100%) adult worm mortality at 3-5 mg/mL and total egg-hatch inhibition at 4-5 mg/mL (p < 0.05). The LD₅₀ for adult worm mortality was 0.323 mg/mL. In vivo, the high-dose group (1.6 mg/kg) achieved a 76.2% fecal-egg-count reduction, exceeding oxfendazole (69.7%). No significant changes in alanine aminotransferase or aspartate aminotransferase were observed (p > 0.05), confirming hepatic safety, while serum proteins and red-blood-cell indices improved significantly (p < 0.05).

Conclusion: Purified alkaloid fractions of N. tabacum, particularly the ethyl acetate extract containing nicotine, demonstrated strong, dose-dependent anthelmintic activity, and safety against benzimidazole-resistant H. contortus. These findings support N. tabacum as a sustainable, plant-based alternative to synthetic anthelmintics. The work advances the One Health framework and contributes directly to SDG 2 (Zero Hunger), SDG 3 (Good Health and Well-being), SDG 12 (Responsible Consumption and Production), and SDG 15 (Life on Land).

Background and aim: Vitrification is a promising cryopreservation technique for conserving the genetic resources of Aceh cattle; however, it may induce cryoinjury and follicular apoptosis. Pituitary extract (PE), containing follicle-stimulating hormone (FSH) and luteinizing hormone (LH), can potentially mitigate apoptosis and maintain follicular viability. This study investigated the effect of bovine PE supplementation in vitrification media on the expression of caspase-3, FSH receptor (FSHR), and LH receptor (LHR) in vitrified ovarian tissue of Aceh cattle.

Materials and methods: A factorial, completely randomized design was employed using five vitrification media, PE at 0, 200, 400, and 600 μg/mL, and commercial bovine PE (Gibco, 300 μg/mL), combined with three vitrification durations (0, 7, and 14 days), each in triplicate. Post-vitrification ovarian tissue was evaluated by immunohistochemistry for caspase-3, FSHR, and LHR expression. The intensity scores (IS) were analyzed using the Kruskal-Wallis and Mann-Whitney U tests (p < 0.05).

Results: PE supplementation significantly (p < 0.05) reduced caspase-3 expression across all follicular stages, indicating decreased apoptosis, whereas vitrification duration alone showed limited effects. The lowest caspase-3 IS (negative) occurred in the 600 μg/mL PE group after 7 days. Both PE concentration and vitrification duration significantly influenced FSHR and LHR expression (p < 0.05), with strong positive interactions between the two factors. FSHR and LHR expression increased progressively from primordial to antral follicles, suggesting preserved gonadotropin responsiveness. Optimal follicular preservation and receptor integrity were achieved at 600 μg/mL PE following 7 days of vitrification.

Conclusion: Supplementation of vitrification media with 600 μg/mL bovine PE effectively suppresses follicular apoptosis while enhancing FSHR and LHR expression, maintaining ovarian functionality after vitrification. These results highlight PE as a low-cost, multi-hormonal alternative to single-gonadotropin supplements in cryopreservation media, supporting sustainable genetic conservation of Aceh cattle. Integrating locally derived PE into cryopreservation protocols could improve post-thaw follicular survival, reduce dependency on commercial reagents, and strengthen reproductive biotechnology for indigenous livestock conservation.

Background and aim: Rabies remains a fatal but preventable zoonotic disease causing nearly 59,000 human deaths annually worldwide, including approximately 75 cases/year in Vietnam. Despite the National Rabies Prevention and Control Program (2022-2030) targeting zero human deaths, community-level awareness and responsible dog management remain key determinants of program success. This study assessed knowledge, attitudes, and practices related to rabies prevention and dog management among residents of Hung Yen province.

Materials and methods: A community-based cross-sectional survey was conducted among 210 residents from Khoai Chau, Van Lam, and Yen My districts between November and December 2022. Data were collected using a structured, pre-tested questionnaire covering demographics, rabies knowledge, and dog ownership practices. Descriptive statistics and Chi-square tests were performed in R software, with p < 0.05 considered statistically significant.

Results: Among 210 respondents, 82.4% had heard of rabies, and 60.7% demonstrated good knowledge. Most knew that dog bites transmit rabies (97.7%), but 39.9% were unaware that scratches can also cause infection. More than half (52.6%) still believed traditional remedies could prevent rabies, and 39.7% did not seek medical care after dog bites. Younger respondents (18-40 years) had significantly better knowledge (odds ratio = 1.90; p = 0.04). Among 85 dog owners, 82.4% vaccinated their dogs, yet 21.2% allowed dogs to roam freely, and 91.8% did not spay or castrate them. Higher socioeconomic status and urban residence were associated with better dog management practices.

Conclusion: Despite Hung Yen's low rabies fatality, notable gaps persist in community awareness and responsible pet ownership. Misconceptions about transmission routes and reliance on traditional treatment threaten progress toward the 2030 rabies-free goal. Strengthened One Health-based education, targeting older adults and low-income rural groups, is recommended to promote timely post-exposure prophylaxis and sustainable dog vaccination and population control programs.

Background and aim: Toxoplasma gondii is an obligate intracellular protozoan responsible for reproductive losses in sheep and significant zoonotic transmission to humans. Despite its known presence in Algeria, regional epidemiological data remain inconsistent. This study aimed to determine the seroprevalence of T. gondii and identify associated risk factors among aborted ewes in Tebessa Province, northeastern Algeria, within a One Health framework.

Materials and methods: A cross-sectional survey was conducted from September 2019 to October 2020 across three communes (Tlidjen, Al Ater, and Negrine). Serum samples (n = 297) were collected from recently aborted Ouled Djellal ewes aged 2-5 years. Anti-T. gondii immunoglobulin G antibodies were detected using the Toxo-Screen DA direct agglutination test at a 1:40 dilution. Risk factors, including location, parity, gestational stage, farming system, and presence of carnivores, were analyzed by χ² tests and multivariate logistic regression using R v4.0.3.

Results: The overall seroprevalence was 48.48% (144/297). Significant differences were observed across communes (Tlidjen 59.03%, Al Ater 42.72%, Negrine 30.00%; p < 0.001). Higher prevalence was recorded in sedentary (58.54%) than transhumant (26.09%) systems (odds ratio [OR] = 5.28; 95% confidence interval [CI]: 2.83-9.85; p < 0.001) and in farms with carnivores (63.31% vs. 28.91%; OR = 2.90; p < 0.001). Multiparous ewes were less likely to be seropositive than primiparous ones (OR = 0.55; p = 0.047). No significant association was found for gestation stage (OR = 1.58; p = 0.111).

Conclusion: The high seroprevalence of T. gondii in aborted ewes indicates active environmental transmission and considerable reproductive and zoonotic risks in Tebessa. Strengthened farm biosecurity, feline population management, and public awareness of meat hygiene are urgently needed. Integrating veterinary, environmental, and public health surveillance will improve toxoplasmosis control within the One Health framework.

Background and aim: Insulin-like growth factor-1 (IGF-1) plays a crucial role in folliculogenesis and oocyte maturation by regulating oxidative stress and apoptotic pathways. However, the optimal IGF-1 concentration for small ruminant oocytes, particularly the native Kacang goat, remains undefined. This study aimed to determine the optimal IGF-1 dose for improving oocyte quality during in vitro oocyte maturation (IVM) by evaluating oxidative stress and apoptosis markers.

Materials and methods: Ovaries (n = 120) were collected from local slaughterhouses, and cumulus-oocyte complexes were aspirated, selected, and randomly divided into four groups: Control (0 ng/mL IGF-1) and treatments with 50, 100, and 150 ng/mL IGF-1 supplementation. Mature oocytes were analyzed for oxidative stress biomarkers, including superoxide dismutase (SOD-1), glutathione (GSH), and malondialdehyde (MDA), using an enzyme-linked immunosorbent assay, and for apoptosis regulators, B-cell lymphoma 2-associated X protein (BAX), B-cell lymphoma-2 (BCL-2), and cytochrome c, using immunocytochemistry. Data were analyzed using one-way analysis of variance and Duncan's post hoc test (p < 0.05).

Results: IGF-1 supplementation produced concentration-dependent effects. The 100 ng/mL group (T2) exhibited the highest SOD-1 (2.07 ± 0.60) and GSH (8.07 ± 1.79) levels (p < 0.05), while MDA increased with higher IGF-1 doses, indicating a threshold beyond which oxidative stress is induced. Anti-apoptotic BCL-2 and cytochrome c expressions peaked at 50 ng/mL IGF-1 (10.73 ± 1.56 and 11.73 ± 0.99, respectively), whereas the pro-apoptotic marker BAX was lowest in the same group and increased at higher doses. The findings suggest that 50 ng/mL IGF-1 effectively maintains redox balance and mitochondrial stability through phosphatidylinositol 3-kinase/protein kinase B-mediated regulation.

Conclusion: This study demonstrates, for the 1^st time, a dose-dependent, biphasic effect of IGF-1 on oxidative and apoptotic pathways in Kacang goat oocytes. An optimal concentration of 50 ng/mL IGF-1 enhances oocyte maturation by balancing antioxidant defense and anti-apoptotic mechanisms, whereas higher concentrations induce oxidative stress. These findings establish a breed-specific IVM optimization protocol that supports genetic preservation and sustainable reproductive biotechnology for indigenous goats.

Background and aim: The gut microbiota of broilers plays a pivotal role in nutrient absorption, immune modulation, and mineral metabolism. Feed additives can influence these microbial and physiological processes, yet their integrated effects remain insufficiently understood. This study aimed to intelligently evaluate the impact of various feed additives on the intestinal microbiota and mineral composition of broiler chickens and to develop machine learning (ML) models for clustering and classification of diet-associated mineral and microbial profiles.

Materials and methods: A total of 385 Arbor Acres broilers (7 days old) were allocated into 11 groups, including one control semi-synthetic diet (SSD), one group with a semi-synthetic deficient diet (SSDD), and nine experimental groups receiving SSDD with different additives: Probiotics (Soya-bifidum and Sporobacterin), dietary fibers (cellulose, lactulose, and chitosan), enterosorbents (enterosgel and activated carbon), and ultrafine particles (UFPs) (Cu and Fe). Microbiota composition was assessed by 16S ribosomal RNA sequencing, and body mineral composition was determined through inductively coupled plasma mass spectrometer. To overcome data scarcity, synthetic records were generated using conditional tabular generative adversarial networks. K-means and hierarchical agglomerative clustering were used for mineral profile grouping, while logistic regression, SVM, and decision tree models classified diet types.

Results: Hierarchical clustering revealed six distinct mineral profile groups (Silhouette = 0.524), with SSD and SSDD forming separate clusters. Feed additives such as UFPs, chitosan, and activated carbon induced similar mineral patterns. Key differentiating biomarkers were cobalt, zinc, strontium, arsenic, and lithium (p < 0.05). The decision tree classifier achieved 74% accuracy in predicting diet types based on microbiota data. Alpha diversity analysis showed enhanced microbial richness in groups fed lactulose, enterosgel, cellulose, or activated carbon.

Conclusion: ML effectively elucidated complex relationships between diet, microbiota composition, and mineral metabolism in broilers. The integration of clustering and predictive models demonstrates the feasibility of intelligent feeding systems tailored to optimize gut health and nutrient utilization. Future studies integrating multi-omics data and broader farm-level validation will strengthen precision nutrition frameworks for sustainable poultry production.

Background and aim: Zoonotic malaria poses an emerging challenge in Southeast Asia, where rapid urbanization and deforestation increase human-wildlife interactions. Macaques are important natural reservoirs for Plasmodium species due to their evolutionary proximity to humans. Understanding host-specific immune responses to malaria in free-living macaques may aid biomarker discovery and guide surveillance strategies. This study aimed to characterize serum proteomic profiles in three wild macaque species, Macaca fascicularis (Mf), Macaca leonina (Ml), and Macaca arctoides (Ma), naturally infected with zoonotic Plasmodium spp., and to identify conserved proteins with biomarker potential.

Materials and methods: Blood samples from 61 macaques (25 Ml, 32 Ma, 4 Mf) were screened for Plasmodium species using nested polymerase chain reaction (PCR). Serum proteomes were analyzed using liquid chromatography-tandem mass spectrometry, followed by bioinformatics-based differential protein expression analysis, pathway enrichment, gene ontology classification, and construction of protein-protein interaction (PPI) networks. Comparative analyses were performed across species to identify conserved expression signatures.

Results: Nested PCR confirmed Plasmodium infections in 20.00% of Ml, 50.00% of Ma (34.78% zoonotic), and 100% of Mf samples. Proteomic profiling identified 9,525 serum proteins, of which 698 were differentially expressed across species. Thirty-six proteins formed robust PPI subnetworks linked to immune defense, apoptosis, DNA repair, calcium signaling, and cytoskeletal remodeling. Ml exhibited predominant protein upregulation, whereas Mf and Ma showed downregulation trends, indicating species-specific immune adaptations. Notably, six of nine previously reported malaria-associated proteins (including CARD domain-containing protein, interleukin 1 receptor-associated kinase 1, and non-specific serine/threonine protein kinase) were consistently expressed across all species, supporting their potential as conserved biomarkers.

Conclusion: Free-living macaques demonstrate distinct proteomic responses to Plasmodium infection, with Ml mounting a stronger immune response relative to Ma and Mf. The identification of conserved immune-related proteins highlights their translational potential as biomarkers for zoonotic malaria in humans. These findings advance the understanding of host-parasite interactions in natural macaque populations and provide a foundation for selecting optimal primate models, improving surveillance, and developing targeted interventions against zoonotic malaria.

Background and aim: The rapid expansion of Thailand's pet industry has influenced dog owners' purchasing behaviors and feeding practices, with potential implications for canine health. Non-communicable diseases (NCDs) such as obesity, renal disease, cardiovascular disease, and diabetes mellitus are increasingly recognized in companion animals, yet the links between diet and these conditions remain underexplored in emerging pet markets. This study aimed to assess the purchasing and feeding behaviors of Thai dog owners, their knowledge of canine nutrition, and the association between diet type and NCD occurrence.

Materials and methods: Data were collected between October 2023 and September 2024 using two survey approaches: An online questionnaire completed by 411 dog owners across Thailand and face-to-face interviews with 201 owners at Chulalongkorn University's Small Animal Teaching Hospital. A total of 612 valid responses were analyzed using descriptive statistics, Chi-square tests, and multiple logistic regression to identify risk factors for NCDs.

Results: Owners prioritized palatability, price, and brand when purchasing food, relying primarily on personal research over veterinary advice. Of respondents, 211 fed commercial diets (valued for convenience and nutritional balance), whereas 190 preferred homemade diets, often lacking supplementation. Mixed feeding was common and carried the highest NCD risk (adjusted odds ratio = 1.783; 95% confidence interval: 1.173-2.710; p = 0.007). Among 169 diagnosed cases, obesity was most prevalent (70.4%), followed by cardiovascular disease (40.2%), renal disease (23.1%), and diabetes mellitus (8.9%). Age was significantly associated with renal and cardiovascular disease, while breed predisposed small dogs to heart disease. Only 35.2% of homemade diets were nutritionally balanced.

Conclusion: Diet type is strongly linked to NCD occurrence, with mixed commercial-homemade feeding posing the greatest risk. Obesity emerged as the most common NCD, with age and breed further influencing disease susceptibility. Knowledge gaps in nutrition and limited veterinary involvement highlight the urgent need for structured educational programs and national guidelines. Within a One Health framework, improving canine feeding practices not only enhances pet welfare but also supports broader household and public health.

Background and aim: Apicomplexan parasites of the genus Sarcocystis exhibit complex two-host life cycles involving birds as both intermediate hosts (IH) and definitive hosts (DH). Despite Colombia's exceptional avian diversity, knowledge of Sarcocystis species in its wild birds remains limited. This study aimed to characterize the morphology and genetic identity of Sarcocystis species infecting three Colombian birds, the Great Kiskadee (Pitangus sulphuratus), American black vulture (Coragyps atratus), and Andean condor (Vultur gryphus).

Materials and methods: Muscle samples from the three species were examined histologically using hematoxylin and eosin, periodic acid-Schiff, and toluidine blue staining. Transmission electron microscopy (TEM) was performed on P. sulphuratus samples to assess ultrastructural features. DNA was extracted and subjected to polymerase chain reaction amplification and sequencing of 18S ribosomal RNA, cytochrome c oxidase subunit 1, and internal transcribed spacer 1 region. Sequences were compared to GenBank data, and phylogenetic analysis was performed using the Maximum Likelihood method.

Results: Two Sarcocystis species were identified. A novel species, Sarcocystis cooperii n. sp., was described from the Great Kiskadee, representing the first record of this species in South America. TEM revealed thin-walled (<1 μm), flat cysts with knob-like blebs corresponding to type 1a morphology. Molecular data showed 99.9% similarity with Sarcocystis sp. ex Accipiter cooperii, confirming its identity as S. cooperii n. sp., with the Cooper's hawk acting as the putative DH. The Sarcocystis sp. detected in C. atratus and V. gryphus was genetically identical to isolates from Brazilian birds and closely related to S. lari, indicating a shared lineage among scavenging Cathartiformes.

Conclusion: This study expands current knowledge of avian Sarcocystis diversity in the Neotropics, documenting S. cooperii n. sp. in P. sulphuratus and the first record of Sarcocystis sp. in two Cathartiformes species in Colombia. These findings underscore the ecological importance of synanthropic and scavenging birds in Sarcocystis transmission dynamics and highlight the need for further research on host-parasite relationships and potential conservation implications for endemic avifauna.