Abstract
Figures and Tables
Fig. 1
Distribution of experimentally induced Mycoplasma (M.) hyosynoviae-associated clinical cases. Clinical observations were collected daily from 0 to necropsy across all groups. A Chi-squared test was used to compare the distribution of clinical cases (p < 0.05). Overall, a higher percentage of cases was seen in animals inoculated with isolate 3491 than 3496. The intravenous (IV) route led to a more rapid development of clinical signs compared to intranasal (IN) injection. Moreover, IV and 10 mL inoculation with isolate 3491 led to longer duration of clinical disease than 3496 (p < 0.05). The results for the negative control group are not depicted above since there was a complete absence of clinical cases for those animals.
![jvs-17-489-g001](/upload/SynapseData/ArticleImage/0118jvs/jvs-17-489-g001.jpg)
Fig. 2
Mean lameness score (mean + SEM) across M. hyosynoviae inoculated groups. All observations were taken daily from 0 to necropsy. The clinical lameness scoring system varied from 0 to 3 corresponding to no lameness, slight, moderate, or severe clinical signs. The Chi-squared and the Friedman's tests were used to compare the distribution of severity of cases across groups (p < 0.05). A significantly higher mean lameness score was observed for animals inoculated IN with 10 mL of isolate 3491 than for all other groups between 10 to 14 (p < 0.05). Results for the negative control group are not shown because of the lack of clinical lameness for those animals.
![jvs-17-489-g002](/upload/SynapseData/ArticleImage/0118jvs/jvs-17-489-g002.jpg)
Fig. 3
Percentage of quantitative polymerase chain reaction assays (qPCR) positive joints for M. hyosynoviae by isolate, individually or combined. Overall, a higher percentage of qPCR positive samples was found in all cases for two anatomical locations: the humero-radial and coxi-femoral joint. However, a broad distribution of this pathogen is seen given that at least 30% of any given joint sample tested positive for the organism. The control group was not included here since none of the joint samples in that group tested positive for M. hyosynoviae by qPCR.
![jvs-17-489-g003](/upload/SynapseData/ArticleImage/0118jvs/jvs-17-489-g003.jpg)
Fig. 4
Distribution of the percentage of M. hyosynoviae qPCR positive joints by isolate and anatomical location. Significant differences in the proportion of M. hyosynoviae tested positive joints were found when comparing across inoculated groups by anatomical location. Asterisks mark the inoculated groups (isolate and/or volume of inocula) that differ significantly for each joint cavity (p < 0.05). A higher percentage of M. hyosynoviae positive joints was found for the following groups: 5 mL IN 3491, 10 mL IN 3491, and 10 mL IN 3496 for the humero-radial joint, 2 mL IV 3491 and 3496 for the coxi-femoral joint, and 2 mL IV 3496 for the femoro-tibial joint compared to other challenged and control groups (p < 0.05). Data for the control group are not depicted due to the absence of detection for this bacterium.
![jvs-17-489-g004](/upload/SynapseData/ArticleImage/0118jvs/jvs-17-489-g004.jpg)
Fig. 5
Box-plot whiskers depicting the comparative analysis of M. hyosynoviae microscopic alterations by joint cavity. Histopathology scores (ranging from minimum to maximum) are depicted across all panels. (A) Scapulo-humeral joints. (B) Humero-radial joints. (C) Coxi-femoral joints. (D) Femoro-radial joints. (E) Tibio-tarsal joints. Statistical analysis was conducted by comparing all groups using the non-parametric one-way ANOVA Kruskal-Wallis test followed by multiple comparisons with Dunn's test. Different letters above the box-plot whiskers data indicate significantly differences across groups (p < 0.05).
![jvs-17-489-g005](/upload/SynapseData/ArticleImage/0118jvs/jvs-17-489-g005.jpg)
Table 1
Odds ratio comparing diseased vs. non-diseased animals based on the defined M. hyosynoviae-associated disease diagnostic criteria
![jvs-17-489-i001](/upload/SynapseData/ArticleImage/0118jvs/jvs-17-489-i001.jpg)
*Both qPCR and histopathological metrics were used as binary outcomes (i.e., 0 or 1), as part of the diagnostic criteria used to predict clinical disease post-exposure to M. hyosynoviae. The comparison was set to test the effects of the impact of having M. hyosynoviae in the joint in addition to a significantly altered microscopic score. OR and 95% CI are depicted for all joint cavities assessed in the study. The OR threshold of significance is equal to 1 since the presence of this value within the 95% CI indicates absence of differences in the ratio between diseased and non-diseased animals given the criterion of interest. †These values in the table indicate that both the humero-radial and femoro-tibial joints showed no significant difference between the diseased and non-diseased animals.
Acknowledgments
References
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)
![crossref](/image/icon/bnr_ref_cross.gif)