BMC Veterinary Research最新文献

{"title":"Short-term effects of a synbiotic diet on thyroid and sex hormones in Sarabi Dogs.","authors":"Ali Khatami, Hadi Pourjafar, Mehrdad Neshat Gharamaleki","doi":"10.1186/s12917-025-04763-3","DOIUrl":"https://doi.org/10.1186/s12917-025-04763-3","url":null,"abstract":"<p><strong>Background: </strong>Synbiotic products are those Functional foods/feeds that contain both probiotic and prebiotic strains and have health-promoting effects beyond probiotics or prebiotics alone. This study aimed to investigate the effect of synbiotic feed containing the probiotic strain Lactobacillus acidophilus La5 (10¹² cfu/g) and inulin (5%) on changes in Thyroid hormones (T3, T4), TSH, LH, FSH, and Testosterone in male dogs throughout 24 days.</p><p><strong>Materials and methods: </strong>In addition to the basic feed, the dogs in the treatment group also received the synbiotic supplement at 5% in each of their three meals during 24 days. Then, the serum levels of LH, FSH, TSH, and Testosterone were measured with an ELISA kit and finally, the obtained data were statistically analyzed.</p><p><strong>Results: </strong>The results showed that the consumption of this formulated synbiotic feed had no negative effect on the profile of Thyroid hormones (T3: from 1.09 ± 0.51 to 0.95 ± 0.40 ng/ml [p > 0.05]; and T4: from 6.60 ± 4.33 to 4.70 ± 4.29 µg/dl [p > 0.05]) as well as TSH (from 0.07 ± 0.09 to 0.03 ± 0.00 mIU/L [p > 0.05]), Testosterone (from 1.56 ± 0.66 to 1.26 ± 0.93 ng/ml [p > 0.05]), FSH (from 4.72 ± 1.12 to 11.55 ± 3.42 mIU/ml [p = 0.008]), LH (from 0.56 ± 0.48 to 0.31 ± 0.15 mIU/ml [p > 0.05]), and the changes in the amounts of these hormones was in the normal range during 24 days.</p><p><strong>Conclusion: </strong>It concluded that the consumption of synbiotic feed (L. acidophilus + inulin, at the rate of 5%) in male dogs has no significant adverse effects were observed within the study period on Thyroid, TSH, and sex hormones and it seems that it may be used for a long time to take health-promoting effects without harming hormonal activities.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"314"},"PeriodicalIF":2.3,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12046685/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143954095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A premier case report of a congenital pseudocyst of the testis (cystis spuria testiculi congenita) in a three-week-old calf.","authors":"Jędrzej M Jaśkowski, Maciej Kaptur, Bartłomiej M Jaśkowski, Serhii Kulynych, Marek Gehrke","doi":"10.1186/s12917-025-04775-z","DOIUrl":"https://doi.org/10.1186/s12917-025-04775-z","url":null,"abstract":"<p><strong>Background: </strong>Cysts in the testicular parenchyma are extremely rare in bulls and are typically detected during ultrasound examinations. In contrast, pseudocysts are exceedingly uncommon. This paper describes a case involving a large pseudocyst in a few-day-old calf.</p><p><strong>Case presentation: </strong>The circumference of the identified structure was 25 cm, with a length of 14 cm and a width of 8 cm. The skin of the scrotum was movable, and the consistency of the formation was elastic. The structure was positioned obliquely, with its apex reaching the proximal part of the ankle. Ultrasonography revealed the presence of a large normoechoic fluid space, with small, irregularly shaped fragments of tissue exhibiting significant hyperechogenicity. The structure was surgically excised. Histopathological analysis indicated changes consistent with a pseudocyst. The bull's karyotype was normal (60XY), and the biochemical and haematological parameters were within physiological ranges. Testosterone concentrations on the day of surgery and at 10 months of age were measured at 0.02 ng/ml and 0.07 ng/ml, respectively.</p><p><strong>Conclusions: </strong>This case report represents the first documented instance of an abnormally large testicular pseudocyst in a bull. The surgical removal of the pseudocyst was performed safely and successfully, with no adverse effects observed on the calf's subsequent growth and development.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"306"},"PeriodicalIF":2.3,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12046683/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143976359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro expression of the goose astrovirus Cap protein delivered with a duck enteritis virus vector.","authors":"Liu Chen, Yinchu Zhu, Tao Yun, Weicheng Ye, Zheng Ni, Jionggang Hua, Yuan Fu, Cun Zhang","doi":"10.1186/s12917-025-04654-7","DOIUrl":"https://doi.org/10.1186/s12917-025-04654-7","url":null,"abstract":"<p><strong>Background: </strong>Goose astrovirus (GAstV) is an emerging pathogen that is widely distributed throughout China and can cause visceral gout, resulting in serious economic losses for the goose industry. Open reading frame 2 (ORF2) of this virus encodes the precursor capsid protein, which is essential for the assembly and antigenicity of these virions. To construct a bi-valent vaccine for controlling GAstV and duck enteritis virus (DEV) infection, an infectious bacterial artificial chromosome (BAC) clone of the DEV vaccine strain pDEV-EF1 was used to establish a recombinant DEV vector for GAstV ORF2 gene delivery.</p><p><strong>Methods: </strong>GAstV ORF2 expression frame was inserted into the US7 and US8 intergenic region of DEV genome by Red E/T two-step recombinant technology, then the recombinant virus rDEV-GAstV ORF2 was rescued by transfecting recombinant clone pDEV-GAstV ORF2 into chicken embryonic fibroblasts (CEFs). The expression of ORF2 in CEFs and formation of virus-like particles (VLPs) were analysed by Western blotting, indirect immunofluorescence assay (IFA) and immunogold electron microscopy (IEM), individually. And protein celluar localization was analysed by IFA.</p><p><strong>Results: </strong>Using this rDEV-GAstV ORF2 vector to infect CEFs was sufficient to elicit GAstV Cap protein expression, as confirmed by Western blotting and IFA. IEM also revealed the formation of VLPs within cells expressing this Cap protein.</p><p><strong>Conclusions: </strong>DEV is a good viral vector for GAstV ORF2 gene delivery and these results provide a basis for the development of a bivalent vaccine for controlling DEV and GAstV infections.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"311"},"PeriodicalIF":2.3,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12046716/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143972911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alterations in tidal volume over recording time during pulmonary function testing by barometric whole-body plethysmography in client-owned cats: a multicenter retrospective investigation.","authors":"Wei-Tao Chang, Laín García-Guasch, Hannah Gareis, Bianka Schulz, Yoshiki Yamaya, Pei-Ying Lo, Chin-Hao Chang, Hui-Wen Chen, Chung-Hui Lin","doi":"10.1186/s12917-025-04774-0","DOIUrl":"https://doi.org/10.1186/s12917-025-04774-0","url":null,"abstract":"<p><strong>Background: </strong>Pulmonary function assessment in small animal clinical patients typically relies on tidal breathing analysis, such as placing cats in a barometric whole-body plethysmography (BWBP) chamber. Despite its wide application in various clinical scenarios, the recording time for BWBP has not been standardized. Variability in resting tidal volume (TV) during natural breathing is significant, impacting the detection of airflow limitation in obstructive airway disease. This multicenter investigation aimed to examine the consistency of TV alterations over the BWBP recording period across different regions, identify influential factors associated with signalment or emotion of the cat, and determine whether the recording time for BWBP in clinical cats could be shorter than in previous studies.</p><p><strong>Results: </strong>This is a multicenter retrospective study. A total of 131 BWBP recordings from clinical cats across four sites in different countries were enrolled. Ventilatory parameters calculated from short sections using 5 and 20 breaths at the first site showed no significant difference (P > 0.05). Among all sites, TV of the initial period (TV-initial, median 32.5 mL, range 4.9-162.9) was significantly greater than TV of the middle (TV-mid, 29.9 mL, range 6.7-144.6) (P < 0.001) and the late (TV-late, 27.5 mL, range 5.1-144.8) (P < 0.001) period of the recording, while TV-mid and TV-late were not significantly different (P = 0.19). The trend of alterations in TV was not affected by site, emotional status, health status, age, or gender. Forest plots with 95% confidence intervals of TV generated from short sections, alongside conventional data averaging breaths over a 5-minute period (TV-All), showed acceptable margins of error at all sites. TV-mid and TV-late were closest to TV-All, whereas TV-initial was larger than TV-mid, TV-late, and TV-All.</p><p><strong>Conclusions: </strong>TV in clinical cats within the BWBP chamber tends to decrease with recording time. When a shorter section of breaths is desired for clinical evaluation, selecting 5 or 20 breaths from the beginning period of recording would have a higher TV, which might be advantageous for investigating obstructive airway problems. Alternatively, breaths selected from the middle or later stages of recording would be more representative of relaxed breathing over a longer period of time.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"304"},"PeriodicalIF":2.3,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12044765/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143965494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maternal supplementation of Lonicera flos and Scutellaria Baicalensis mixed extracts improve reproduction performance and metabolic health through modulating gut microbiota during pregnancy.","authors":"Mu Wang, Shengnan Yin, Jinghua Cheng, Yuqiang Guo, Huiyuan Lv, Siwen Jiang, Jian Peng, Yuanfei Zhou","doi":"10.1186/s12917-025-04753-5","DOIUrl":"https://doi.org/10.1186/s12917-025-04753-5","url":null,"abstract":"<p><strong>Background: </strong>This study aimed to evaluate the impacts of dietary supplementation with a combination of plant extracts on performance, metabolic health, and gut microbiota of sows. A total of 1003 crossbred pregnancy sows (DanBred Landrace × DanBred Yorkshire, mean parity 4.44 ± 1.84) were assigned to one of the two dietary treatments: a control group (CON, basal diet) and a Lonicera flos and Scutellaria baicalensis mixed extracts group (LSE, basal diet supplemented with 0.5 g/kg of mixed extracts).</p><p><strong>Results: </strong>Supplementation of LSE increased (P < 0.05) the numbers of total born, litter weight and average piglet weight on L21 d, average daily feed intake, and survival rate of piglets during lactation. Compared to CON, LSE group reduced (P < 0.05) interleukin-6 (IL-6) concentration in the feces and plasma on G109 d, while increased (P < 0.05) interleukin-10 (IL-10) concentration on G109 d and on L3 d. Supplementation of LSE had lower (P < 0.05) plasma reactive oxygen species levels on G30 d and on L3 d, and had a reducing tendency (P = 0.07) for thiobarbituric acid reactive substances concentrations and a trend toward increased (P = 0.08) value of homeostatic model assessment of insulin sensitivity of sow plasma on G109 d. In addition, supplementation of LSE increased (P < 0.05) the abundance of Firmicutes and Proteobacteria and decreased (P < 0.05) the abundance of Bacteroidetes and Spirochaetes on G109 d. The abundance of Christensenellaceae_R_7_group, UCG_002, Clostridium_sensu_stricto_1, Escherichia_Shigella, un_f__Christensenellaceae, Bacteroides, and Terrisporobacter were significantly increased (P < 0.05) in the LSE diet group. The abundance of Christensenellaceae_R_7_group, UCG_002 and un_f__Ruminococcaceae were positively correlated with plasma IL-10 (P < 0.01), and negatively correlated with plasma IL-6 and TBARS levels.</p><p><strong>Conclusions: </strong>This study demonstrates that dietary supplementation with Lonicera flos and Scutellaria baicalensis mixed extracts (LSE) at 0.5 g/kg during gestation significantly improves reproductive performance and metabolic health in sows, likely through modulating gut microbiota composition.The observed improvements in performance and health parameters coincide with microbiota-driven inflammation attenuation and redox balance restoration, suggesting a gut-immune axis regulatory role of LSE.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"305"},"PeriodicalIF":2.3,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12044769/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143971914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of different oxygen concentrations on oxidative stress and some biochemical parameters in the transfer of adult rainbow trout (Oncorhynchus mykiss).","authors":"Utku Duran, Sena Çenesiz","doi":"10.1186/s12917-025-04770-4","DOIUrl":"https://doi.org/10.1186/s12917-025-04770-4","url":null,"abstract":"<p><strong>Background: </strong>Transfer operations are one of the stress sources that cause mortality in fish. This study investigated the effects of different dissolved oxygen concentrations on oxidative stress and several biochemical parameters during the transfer of adult rainbow trout (Oncorhynchus mykiss). The aim was to determine the optimum dissolved oxygen concentration to minimize stress and potential tissue damage during transfer.</p><p><strong>Result: </strong>The study analyzed GSH-Px, SOD, and LDH enzyme activities; MDA, Cp, TOS, TAS, OSI, cortisol, glucose, urea, uric acid, creatinine, Ca, Mg, and MDA levels; as well as Cp, TOS, TAS, and OSI values in serum and muscle tissue. Findings indicated that transfer and preparation for transfer induced oxidative damage in fish. Comparing different dissolved oxygen levels, it was observed that hypoxic and hyperoxic conditions increased ROS levels, suppressed the antioxidant mechanism, and caused oxidative stress.</p><p><strong>Conclusions: </strong>Among the tested conditions, transfer under normoxic conditions with a dissolved oxygen concentration of 10 mg/L was the most effective in minimizing oxidative stress and tissue damage. This suggests that maintaining adequate oxygen levels during transfer plays a crucial role in reducing physiological stress in rainbow trout.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"302"},"PeriodicalIF":2.3,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12042426/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144061325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of canine distemper virus (CDV) neutralising antibodies in small ruminants during peste-des-petits-ruminants virus (PPRV) surveillance in Zambia.","authors":"Sara Lysholm, Nicola Logan, Johanna F Lindahl, Mikael Berg, Elin Johansson, Pernilla Karlsson Bergkvist, George Dautu, Ricky Chazya, Brian J Willett, Musso Munyeme, Jonas Johansson Wensman","doi":"10.1186/s12917-025-04732-w","DOIUrl":"https://doi.org/10.1186/s12917-025-04732-w","url":null,"abstract":"<p><p>Canine distemper virus (CDV) is endemic in Zambia, while peste-des-petits-ruminants virus (PPRV) has not been detected. This study screened 962 farmed goats and 237 small ruminants at informal markets for PPRV antibodies using c-ELISA. A subset (n = 29) was re-analysed with virus neutralisation assays (VNA) for antibodies to PPRV and CDV due to cross-reactivity concerns. c-ELISA indicated 6.44% PPRV seroprevalence on farms and 3.80% at markets. While VNA detected no PPRV antibodies, 45% (13/29) tested positive for CDV, possibly suggesting cross-reactivity. Given the study's limitations, further research is needed to determine whether PPRV is present in Zambia and assess potential cross-reactivity.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"303"},"PeriodicalIF":2.3,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12042581/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143973905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of multidrug-resistant and pathogenic Plesiomonas shigelloides from endangered crested ibis (Nipponia nippon).","authors":"Jing Xia, Lele Shao, Xuanyi Chen, Yi Ji, Wulin Ma, Keyuan Chen, Guoqiang Qiu, Houhui Song, Yongchun Yang","doi":"10.1186/s12917-025-04755-3","DOIUrl":"https://doi.org/10.1186/s12917-025-04755-3","url":null,"abstract":"<p><p>Plesiomonas shigelloides (P. shigelloides) is a gram-negative, thermotolerant, motile, and pleomorphic microorganism that acts as an opportunistic pathogen, capable of causing abscesses, enteric infections, and even sepsis in humans and other animals, thereby posing a threat to human and animal health worldwide. The crested ibis (Nipponia nippon) is a globally endangered avian species with a limited population and is vulnerable for various infections. To gain a better understanding of the prevalence of P. shigelloides in the endangered crested ibis, fecal samples from the crested ibis at the Xiazhu Lake Crested Ibis Breeding Research Center, China were collected and analyzed. The results confirmed that 45.6% (36/79) of the fecal samples tested positive for P. shigelloides. Antibiotic susceptibility testing showed that 27.8% (10/36) of P. shigelloides isolates were multidrug-resistant, with resistance to ampicillin and amikacin being 100% and 77.8%, respectively. Subsequently, ten representative isolates were subjected to whole genome sequencing, and resistance and virulence genes were analyzed. The evolutionary tree of the genomes show that these strains have different origins, with one strain closely related to a strain from human. Finally, the pathogenicity experiment demonstrated that several strains exhibit pathogenicity in both mice and waterfowl, with two strains displaying lethal pathogenicity in mice. To the best of our knowledge, this is the first report of multidrug-resistant and pathogenic P. shigelloides isolated from the crested ibis, suggesting a potential threat to this endangered species and broader public health implications.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"299"},"PeriodicalIF":2.3,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12038971/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143973507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel presentation and pathophysiology of heavy parasitic burdens in Weddell seals (Leptonychotes weddellii) during sedation.","authors":"Michelle R Shero, Kathy Burek-Huntington, Robert McCorkell, Steven A Nadler, Caroline L Rzucidlo, Amy C Klink, Allyson G Hindle, Jennifer M Burns, Shawn Johnson","doi":"10.1186/s12917-025-04740-w","DOIUrl":"https://doi.org/10.1186/s12917-025-04740-w","url":null,"abstract":"<p><strong>Background: </strong>Marine mammals act as sentinel species, with top predators' overall health reflecting their ecosystem, integrated across multiple trophic levels. Yet apparently healthy wild animals may have significant subclinical pathology that goes undetected due to unknown medical histories. Marine mammals, particularly phocid seals, often suffer from heavy parasite burdens. While there are documented cases of severe respiratory infections resulting in complications during sedation, there have been no reports of gastrointestinal parasites contributing to poor outcomes during examinations requiring sedation or anesthesia. This report describes two unique presentations of high intestinal parasite loads that purportedly predisposed Weddell seals (Leptonychotes weddellii) to complications under sedation, and characterizes underlying pathology.</p><p><strong>Case presentation: </strong>Two adult female Weddell seals exhibited prolonged apnea and vomiting while under intravenous sedation, that led to aspiration and mortality despite resuscitation attempts. Post-mortem examination revealed a severe Diphyllobothrium tapeworm impaction in the duodenum, with the parasitic mass causing a partial or complete obstruction. In both cases, the stomach was remarkably distended, suggesting the parasitic mass slowed gastric emptying. Both animals' stomachs contained a high parasite burden with roundworms embedded into the mucosa. Histological analysis identified underlying pathological conditions that were likely parasite related, including chronic pneumonia associated with lungworm infestations, reactive, depleted and fibrosed lymph nodes, granulomatous lymphadenitis and hepatitis. Further examination in one of the animals revealed severe gastritis and necrotizing duodenitis at the site of the cestode infection.</p><p><strong>Conclusions: </strong>To our knowledge, this is the first description of a significant gastrointestinal parasitic impaction being linked to acute distress during sedation in a marine mammal. We provide an in-situ depiction of the severe cestode infection. It is noteworthy that both animals in this case study exhibited histopathology consistent with chronic inflammation across multiple organ systems. Whether animals were sufficiently immunocompromised that rapid parasite growth became unchecked, or whether the parasite infestation led to dysfunction in other organs remains unresolved. We discuss the potential for premedication with prokinetic agents that increase esophageal sphincter tone to mitigate complications in future late-summer Weddell seal handlings.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"300"},"PeriodicalIF":2.3,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12039106/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143973100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sheep challenged with sheep-derived type II Mycobacterium avium subsp. paratuberculosis: the first experimental model of paratuberculosis in China.","authors":"Meng-Yuan Li, Wei-Kang Meng, Wei Ma, Yu-Lin Ding, Bo Yang, Wei-Hong Zhao, Hasi Bayaer, Alateng Bagen, Rui-Bin Chen, Siqin Tunala, Rong Zhang, Chen-Guang Du, Li Zhao, Yong-Hong Liu","doi":"10.1186/s12917-025-04765-1","DOIUrl":"https://doi.org/10.1186/s12917-025-04765-1","url":null,"abstract":"<p><strong>Background: </strong>Paratuberculosis (PTB), caused by Mycobacterium avium subsp. paratuberculosis (MAP), is difficult to diagnose in the early stages and poses substantial challenges in prevention, control, treatment, and eradication. A well-defined animal model can help identify disease markers and serve as a platform for vaccine and drug development. This study used sheep as a ruminant model for experimental MAP infection research.</p><p><strong>Methods: </strong>Nine 3-month-old lambs with negative MAP antigen and antibody were divided into three groups (control group A and inoculated groups B and C). The inoculated groups were challenged with sheep-derived type II MAP. After exposure, we recorded clinical signs, assessed fecal shedding, tested blood MAP levels, and performed fecal cultures. We also measured MAP-specific antibodies and monitored IFN-γ and IL-10 responses in vivo. At 255 days after inoculation, we performed autopsy, tissue culture, pathomorphological observation, and bacterial organ burden (BOB) testing.</p><p><strong>Results: </strong>All six sheep in groups B and C were infected, regardless of the challenge dose and exhibited emaciation; two had intermittent soft stools. Intermittent MAP shedding in feces was observed from 60 to 255 days after exposure. Typical MAP colonies formed after 4-6 weeks of fecal and tissue culture, and Ziehl-Neelsen staining showed positive results. In the groups challenged with MAP, some blood samples tested positive for MAP and MAP-specific antibodies were detected in some serum samples. IFN-γ response was significantly higher in groups B and C than that in group A from day 60 post-exposure, whereas the IL-10 response was higher than that in group A from day 120 post-exposure. In the infected groups, the ileal lesions were the most severe and were classified as grade 3 PTB granulomatous inflammation (multibacillary lesions). BOB levels varied across different tissues.</p><p><strong>Conclusions: </strong>To the best of our knowledge, this is the first experimental MAP challenge study on sheep in China. Polymerase chain reaction detection was more sensitive than MAP culture, whereas enzyme-linked immunosorbent assay was less sensitive for detecting MAP-specific antibodies. IFN-γ and IL-10 responses may serve as targets for monitoring PTB progression. The severity of ileal lesions and acid-fast bacilli grading play crucial roles in the understanding of infection dynamics. Currently, early PTB diagnosis requires a combination of multiple sample types and detection methods.</p>","PeriodicalId":9041,"journal":{"name":"BMC Veterinary Research","volume":"21 1","pages":"298"},"PeriodicalIF":2.3,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12039145/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143963625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}