BMC Veterinary Research最新文献

Background: Camel milk is known to have hypoglycemic properties. Previous studies found that camel milk exosomes (CM-exo) may regulate cellular glucose metabolism through the inhibition of mitochondrial complex I, but this hypothesis has not been verified by other experiments. The objective of this study was to verify the hypothesis that CM-exo regulated glucose metabolism in hepatocytes by inhibiting mitochondrial complex I pathway. AML12 cells were treated with extracted exosomes from camel milk and the effect of the CM-exo on cell viability was examined by cell counting kit (CCK)-8 assays. The glucose content of the cell culture medium was measured to determine the glucose consumption of the cells. Lactate release from the cells was determined by measuring the lactate content in the cell culture medium. The glycogen content of AML12 cells was detected. The activity of complex I and the contents of ATP, NAD⁺ and NADH were measured. The protein expression levels of adenosine monophosphate-activated protein kinase (AMPK) and phosphorylated AMPK (p-AMPK) were detected by western blotting. The AML12 cells were treated with medium containing CM-exo and gluconeogenic substrates and the glucose content in the cells was determined. The protein expression levels of ten-eleven translocation methylcytosine dioxygenases (TET3), hepatocyte nuclear factor 4α-Promoter 2 (HNF4α-P2), phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G6PC), glycogen synthase kinase 3β (GSK3β) and phosphorylation of GSK3β (p-GSK3β) were detected by western blotting.

Results: The results of this study showed that a high dose of CM-exo inhibited the viability of AML12 cells. It promoted glucose consumption, glycogen content and lactate release in AML12 cells, inhibited complex I activity, ATP content, NAD⁺ content, and NAD⁺/NADH ratio, and increased NADH content. The CM-exo increased the protein levels of p-AMPK, p-GSK3β, the protein expression ratio of p-AMPK/AMPK, p-GSK3β/GSK3β and decreased the glucose content and the protein expression levels of intracellular TET3, HNF4α-P2, PEPCK and G6PC.

Conclusions: By inhibiting the activity of mitochondrial complex I in hepatocytes, CM-exo inhibited oxidative phosphorylation, oxidation of NADH to NAD⁺ and synthesis of ATP, enhanced glycolysis, activated AMPK and resulted in decreased gluconeogenesis and increased glycogen synthesis.

Background: In human medicine, questions regarding heritable disorders are dealt with by clinical geneticists and genetic counselors and both the field, their roles and the tools they use are well-defined. Even though the prevalence of diseases is far higher and scientific literature agrees on expectations towards an increased importance, this does not seem to be the case in veterinary medicine. While we hypothesize that there will be an overlap, some characteristics uniquely linked to veterinary medicine might not be covered.

Methods: To investigate this in-depth and in an attempt to define the field, we compared the internationally accepted definitions and its subparts on genetic counseling in human medicine with what is found in veterinary literature and what was seen in cats and dogs presented at our dedicated small animals clinical genetics/genetic counseling clinic. The results were used in a stepwise analysis that lead to a set of three potential definitions (i.e. on what genetic counseling is, who provides it and which tools are used) that fullfill four criteria (i.e. definitions have to be clear/self-explanatory, minimally sufficient, complete and valid).

Results: The short version of the definition of genetic counseling in veterinary medicine is: "Genetic counseling is the process of helping animal owners and breeders understand - and adapt to - the medical, psychological, familial implications of genetic contributions to disease." Genetic counseling in small animal practice is currently provided by veterinarians and the tools that are used, can be divided in five categories. The signalment of the patients revealed that both cats (30%) and dogs (70%) and various breeds, the two sexes (37% males, 63% females) and all age categories (puppy/kitten-senior) were represented. Furthermore, 73% of the patients were referred by or needed to be referred to other disciplines.

Conclusion: These definitions are derived from human and veterinary literature, and an evaluation based on patient data has demonstrated that these definitions meet all the criteria of a correct definition (i.e. clear, minimally sufficient, complete and valid). With these definitions and case descriptions, our aim is to contribute to the formal foundation of genetic counseling in veterinary medicine.

Background: Campylobacter jejuni (C. jejuni), a major global cause of foodborne bacterial diseases, accounts for more than 90% of all reported cases. Poultry is considered a major reservoir for the transmission of Campylobacter to humans. While extensive research has been conducted abroad on the occurrence and epidemiology of C. jejuni in laying hens, there are scant reports on its prevalence in layer chickens in China. The present study was designed to isolate C. jejuni from 482 cloacal swabs collected from seven laying hen farms located in Hubei Province between January and March 2024. Furthermore, the study aimed to explore the genetic diversity, antibiotic resistance, and virulence gene profiles of the isolated strains.

Results: The overall prevalence of C. jejuni amounted to 4.36% (21/482). Whole-genome sequencing of these 21 isolates revealed 11 distinct sequence types (STs) and eight clonal complexes (CCs), with ST-6522 and CC-443 emerging as the predominant genotypes. Antimicrobial susceptibility testing against 11 antibiotics revealed high resistance rates among C. jejuni isolates, particularly towards ceftriaxone and enrofloxacin, where resistance was universal (100%). Similarly, high resistance levels were also observed for doxycycline (95.24%), ceftiofur (80.95%), tilmicosin (76.19%), and amoxicillin-clavulanic acid (57.14%). Through genomic resistance gene prediction, a total of eighteen resistance genes were identified within the 21 C. jejuni isolates. The most frequently occurring resistance genes were the gyrA (T86I) point mutation (95.14%), cmeR (95.14%), and tet(O) (95.14%). Notably, a robust correlation was discernibled between enrofloxacin resistance and the gyrA (T86I) point mutation, as well as between resistance to ceftriaxone and tilmicosin and the presence of the cmeR gene. Conversely, the correlations between other antibiotic resistance phenotypes and their corresponding resistance genes were less robust. A comprehensive analysis of virulence genes isolated from C. jejuni strains revealed a total of 117 virulence genes, categorized according to their functional roles. These categories encompass adhesion (cadF, jlpA, porA, pebA), invasion (ciaB), motility (flaA, flgB, flhB), toxin production (cdtA, cdtB, cdtC), and immune modulation (htrB, wlaN).

Conclusions: Our results revealed the high resistance rate of C. jejuni from laying-hens in hubei Province, China, which will help the farms take the necessary action to develop effective mitigation strategies for reducing Campylobacter infection in poultry.

Background: Equine gastric ulcer syndrome (EGUS) is a frequent disease in horses that comprises two different entities: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). This disease considerably reduces the quality of life of affected horses and can negatively affect performance. Saliva contains biomarkers, such as oxytocin, that have been used as a welfare indicator and can develop a function as a protective factor against stress-induced changes in gastric function due to its gastric antisecretory and antiulcer effects. The objective of this work was to evaluate changes in salivary oxytocin concentrations in healthy and EGUS horses. For this purpose, an immunoassay based on AlphaLISA technology was validated for the quantification of salivary oxytocin and applied in a total of 102 horses divided into 5 groups: 25 with both EGUS, 23 with only EGGD, 21 with only ESGD, 19 horses with other diseases, and 14 healthy horses.

Results: The analytical validation of the method showed good precision and linearity under dilution. Salivary oxytocin concentrations in healthy horses were higher compared to horses with both ESGD and EGGD and only EGGD. Salivary oxytocin concentrations in horses with only ESGD were higher compared to horses with both ESGD and EGGD and horses with only EGGD. In addition, salivary oxytocin concentrations in horses with other diseases different from ESGD were significantly increased compared to horses with both ESGD and EGGD and horses with only EGGD.

Conclusions: This report validates a new assay that can measure oxytocin in saliva in horses in a precise and accurate way. The lower oxytocin values in horses with EGGD and both EGGD and ESGD than in horses with ESGD, horses with other diseases, and healthy horses could indicate a possible relation of oxytocin with this disease.

Background: A normal visceral arrangement is called situs solitus, whereas a state of visceral arrangement in a mirror-like positional relationship is called situs inversus (SI). Among the SI, the state in which the positions of only some thoracoabdominal organs are reversed is called situs inversus partialis, and the state in which the positions of all thoracoabdominal organs are reversed is called situs inversus totalis (SIT). Clinical information on dogs with SIT is limited.

Case presentation: A 4-month-old Shiba Inu was referred with depression and neurological symptoms as the chief complaints. Computed tomography (CT) revealed the patient had SIT with an extrahepatic portosystemic shunt (EHPSS) and azygos continuation of the caudal vena cava. In addition, complete reversal of the lung lobes and cardiovascular system in the thoracic cavity was confirmed. The patient underwent surgery for partial attenuation of the EHPSS on day 8 after the initial examination. On day 124, after the initial examination, a second surgery was performed for complete attenuation. Under celiotomy, the positions of all abdominal organs, except for the rectum, were inverted; thus, SIT was confirmed via gross observation. In addition, the use of braided nylon sutures partially attenuated the concurrent portocaval shunt. At the conclusion of this study, approximately 6 years had passed since the second surgery, and the patient had a good general condition without any medications.

Conclusion: In SIT, the complex anatomy of the abdominal organs and vessels is difficult to identify via gross observation. In contrast, CT is effective in detecting vascular abnormalities, confirming the anatomical position of each organ, and allowing for the definitive diagnosis of SIT.

Background: Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are significant zoonotic protozoa causing gastrointestinal diseases in humans and animals. However, their prevalence and genotypic characterization in ostriches (Struthio camelus) remain poorly understood. This study aimed to investigate the occurrence and genetic diversity of these parasites in farmed ostriches by the Yellow River in Zhengzhou City, central China. A total of 156 fecal samples were collected and analyzed using polymerase chain reaction (PCR) to determine the prevalence and assess the potential epidemiological roles of ostriches in transmission.

Results: The overall prevalence of Cryptosporidium spp., G. duodenalis and E. bieneusi was 2.56% (4/156), 1.28% (2/156) and 12.2% (19/156), respectively. C. baileyi and G. duodenalis assemblage B were identified in ostriches. Six E. bieneusi genotypes were identified in this study, comprising four previously reported genotypes (EbpA, EbpC, Henan-IV, and Type IV) and two novel genotypes (designated as COW1 and COW2, which differed from known genotypes by two single nucleotide polymorphisms). Among these, EbpC was identified as the predominant genotype. All six genotypes were phylogenetically assigned to zoonotic group 1.

Conclusions: Our findings suggest that ostriches harbor zoonotic genotypes of G. duodenalis and E. bieneusi, indicating they may serve as potential reservoirs for human infection. This underscores the need for effective control measures to prevent environmental contamination and reduce the risk of transmission to humans and other animals.

Background: The therapeutic potential of exosomes derived from mesenchymal stem cells (MSCs) is increasingly recognized in veterinary medicine. This study explored the feasibility of a microcarrier-based three-dimensional (3D) culture system for producing the exosomes (cEXO). Investigations were conducted to enhance production efficiency, ensure stability, and evaluate the therapeutic potential of cEXO for anti-inflammatory applications while assessing their safety profile.

Results: The microcarrier-based 3D culture system improved efficient production of cEXO, yielding exosomes with acceptable profiles, including a size of approximately 81.22 nm, negative surface charge, and high particle concentration (1.32 × 10⁹ particles/mL). Confocal imaging proved dynamic changes in cell viability across culture phases, highlighting the challenges of maintaining cell viability during repeated exosome collection cycles. Characterization via transmission electron microscopy, nanoparticle tracking analysis, and zeta-potential measurements confirmed the stability and functionality of cEXO, particularly when stored at -20 °C. Functional assays showed that cEXO exerted significant anti-inflammatory activity in RAW264.7 macrophages in an inverse dose-dependent manner, with no observed cytotoxicity to fibroblasts or macrophages. Acute toxicity testing in rats revealed no adverse effects on clinical parameters, organ health, or body weight, supporting the safety of cEXO for therapeutic use.

Conclusions: This study highlights the potential of a microcarrier-based 3D culture system for scalable cEXO production with robust anti-inflammatory activity, stability, and safety profiles. These findings advance the development of cEXO-based therapies and support their application in veterinary regenerative medicine.

Background: Calprotectin (S100A8/A9) is a protein related to innate immunity that is considered a biomarker of inflammation. Currently, there is a commercially available automated assay for the measurement of calprotectin concentration (Bühlmann fCal Turbo^® assay), which has been previously validated for saliva and serum of swine and for saliva of horses, and in the canine species it has been validated for use with fecal samples, but it has not been previously validated in canine saliva or serum. Thus, the aim of this study was to perform an analytical validation of an automated assay for the measurement of calprotectin in the saliva and serum of dogs. In addition, changes in this protein in saliva and serum of three diseases with different pathogenic mechanisms - leishmaniasis, pyometra and hyperadrenocorticism - were evaluated. Finally, in these diseases, the correlation of salivary and serum calprotectin with the serum levels of three acute phase proteins (APPs), including C-reactive protein (CRP), haptoglobin (Hp) and ferritin, was also assessed.

Results: The analytical validation results showed that the assay was precise (coefficients of variation < 15% in all cases), accurate (the dilutional parallelism for serum and salivary calprotectin showed observed-to-expected ratios with a mean of 96.9% and 97.2%, respectively), and presented a limit of detection of 0.038 mg/L. When this assay was applied to the different diseases, a significant increase in the concentration of salivary calprotectin in dogs with leishmaniasis (p = 0.0002) and in those with pyometra (p = 0.002), compared to healthy ones, was observed, whereas no significant differences were found in serum. Furthermore, a significant positive moderate correlation was obtained between salivary calprotectin and serum CRP (r = 0.5; p = 0.001) and haptoglobin (r = 0.5; p = 0.002), and between calprotectin and CRP (r = 0.67; p < 0.001) in serum.

Conclusions: Calprotectin (S100A8/A9) can be measured in dog saliva and serum samples by the automated method validated in this study, and when measured in saliva it could be used as a potential biomarker of inflammation and immune activation in the dog.

Background: Betaine is an effective antioxidant and lipopolysaccharide (LPS) is an inflammatory stimulus that can disrupt the antioxidant system. However, the precise mechanisms of betaine's antioxidant activity remain undetermined. This study aimed to examine the impact of betaine on growth, antioxidant capacity, and inflammatory cytokine production in LPS-challenged goslings. In this study, 168 healthy Jiangnan White Goslings (males, 15 days old) were selected and randomly categorized into four groups. There were 7 goslings per replicate and 6 replicates for each treatment. This study employed a 2 × 2 factorial arrangement, the goslings were provided a diet containing 0% or 0.06% betaine and were injected with physiological saline or LPS.

Results: Subsequent analyses revealed that on day 21 of LPS treatment, there was a significant decrease in gosling's ADFI, ADG, and BW, whereas dietary betaine supplementation improved ADFI and BW in LPS-stressed individuals (p = 0.08, p = 0.09). LPS challenge significantly upregulated pro-inflammatory interleukin-1β (IL-1β) mRNA (p < 0.05), whereas betaine significantly lowered these levels (p < 0.05). During the LPS stress period (days 16-21), the superoxide dismutase (SOD) activity and total antioxidant capacity (T-AOC) were significantly reduced, while malondialdehyde (MDA) levels were increased in the liver and jejunal mucosa (p < 0.05). Betaine administration reversed these changes and significantly increased SOD and T-AOC levels while decreasing the MDA content (p < 0.05). However, both LPS and betaine did not affect the mRNA levels of SOD1 or glutathione peroxidase 4 (GSH-Px4) in the liver or jejunal mucosa during the stress (days 16-21) or recovery (days 22-28) periods.

Conclusions: In summary, these analyses revealed that dietary betaine administration can effectively abrogate LPS-induced oxidative liver damage.

Background: Avian hepatitis E virus (HEV) has caused economic losses in the poultry industry and has shown a broad spectrum of infections. In 2022, a quail farm (YangLing, China) exhibited a decrease in egg production, an increase in mortality and hepatosplenomegaly. These characteristics were similar to those of avian HEV infection. To determine whether avian HEV existed on this farm and further clarify the pathogenicity caused by avian HEV under experimental conditions, the livers and spleens were collected from the diseased quails in the field for gross lesion observation and avian HEV detection; then, the pathogenicity was characterized.

Results: In the field, the results showed enlargement of the liver and spleen and hemorrhage spots on the liver, and the amplified fragment (330-bp length) of HEV shared 100% identity with the Chinese avian HEV strain. The pathogenicity of this virus in quail was characterized by decreased egg production, seroconversion, viremia, fecal virus shedding, liver lesions and HEV antigen in the liver under experimental conditions. These differences indicated that there may be other pathogens or factors causing this disease together on the quail farm in addition to avian HEV, and further detection should be performed.

Conclusions: Overall, this is the first study to detect HEV RNA in quails, and an avian HEV strain can successfully infect quails under experimental conditions.