Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern Maryland
Abstract Background Equine granulocytic anaplasmosis (EGA) is a common disease in adult horses, but clinical disease in foals is rarely reported. The relationship between equine maternal and neonatal antibodies to Anaplasma phagocytophilum is unclear. Hypothesis/Objectives That mares in an endemic r...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2023-09-01
|
| Series: | Journal of Veterinary Internal Medicine |
| Subjects: | |
| Online Access: | https://doi.org/10.1111/jvim.16812 |
| _version_ | 1797729011669925888 |
|---|---|
| author | Emily K. Rule Ashley G. Boyle Darko Stefanovski Eman Anis Jennifer Linton Olivia Lorello |
| author_facet | Emily K. Rule Ashley G. Boyle Darko Stefanovski Eman Anis Jennifer Linton Olivia Lorello |
| author_sort | Emily K. Rule |
| collection | DOAJ |
| description | Abstract Background Equine granulocytic anaplasmosis (EGA) is a common disease in adult horses, but clinical disease in foals is rarely reported. The relationship between equine maternal and neonatal antibodies to Anaplasma phagocytophilum is unclear. Hypothesis/Objectives That mares in an endemic region would be seropositive for A. phagocytophilum and that mare and foal serum IgG concentrations for A. phagocytophilum would correlate. Additionally, we hypothesized that foal IgG concentrations for A. phagocytophilum acquired by passive immunity would decline by 6 months of age. Animals Twenty‐two healthy mare‐foal pairs. Methods This prospective observational study investigated serum IgG concentrations specific for A. phagocytophilum in mares and foals using an immunofluorescent antibody test (IFA). The association between foal titer (as a binary variable) and age in months was assessed using a mixed‐effects logistic regression. Results A positive correlation between newborn foal antibody titers and mare titers was identified at both the pre‐foaling (τa = 0.38, τb = 0.50, P = .009) and foaling timepoints (τa = 0.36, τb = 0.47, P = .01). In A. phagocytophilum seropositive neonates, it was unlikely that a positive titer would be detected by 3 months of age (OR = 0.002, P = .02, 95% CI: 0.00001‐0.38). Three out of 20 foals seroconverted between 3 and 6 months of age. Conclusions and Clinical Importance Transfer of specific passive immunity to A. phagocytophilum occurred in 80% of foals born to seropositive mares and declined by 3 months of age. A. phagocytophilum infection should be considered in foals displaying clinical signs consistent with EGA. |
| first_indexed | 2024-03-12T11:22:40Z |
| format | Article |
| id | doaj.art-0fc2f2b4ab5a4b008962ff29b5304ccf |
| institution | Directory Open Access Journal |
| issn | 0891-6640 1939-1676 |
| language | English |
| last_indexed | 2024-03-12T11:22:40Z |
| publishDate | 2023-09-01 |
| publisher | Wiley |
| record_format | Article |
| series | Journal of Veterinary Internal Medicine |
| spelling | doaj.art-0fc2f2b4ab5a4b008962ff29b5304ccf2023-09-01T14:18:40ZengWileyJournal of Veterinary Internal Medicine0891-66401939-16762023-09-013751889189210.1111/jvim.16812Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern MarylandEmily K. Rule0Ashley G. Boyle1Darko Stefanovski2Eman Anis3Jennifer Linton4Olivia Lorello5Department of Clinical Studies, New Bolton Center University of Pennsylvania Kennett Square Pennsylvania USADepartment of Clinical Studies, New Bolton Center University of Pennsylvania Kennett Square Pennsylvania USADepartment of Clinical Studies, New Bolton Center University of Pennsylvania Kennett Square Pennsylvania USADepartment of Pathobiology, New Bolton Center University of Pennsylvania Kennett Square Pennsylvania USAB.W. Furlong and Associates Califon New Jersey USADepartment of Clinical Studies, New Bolton Center University of Pennsylvania Kennett Square Pennsylvania USAAbstract Background Equine granulocytic anaplasmosis (EGA) is a common disease in adult horses, but clinical disease in foals is rarely reported. The relationship between equine maternal and neonatal antibodies to Anaplasma phagocytophilum is unclear. Hypothesis/Objectives That mares in an endemic region would be seropositive for A. phagocytophilum and that mare and foal serum IgG concentrations for A. phagocytophilum would correlate. Additionally, we hypothesized that foal IgG concentrations for A. phagocytophilum acquired by passive immunity would decline by 6 months of age. Animals Twenty‐two healthy mare‐foal pairs. Methods This prospective observational study investigated serum IgG concentrations specific for A. phagocytophilum in mares and foals using an immunofluorescent antibody test (IFA). The association between foal titer (as a binary variable) and age in months was assessed using a mixed‐effects logistic regression. Results A positive correlation between newborn foal antibody titers and mare titers was identified at both the pre‐foaling (τa = 0.38, τb = 0.50, P = .009) and foaling timepoints (τa = 0.36, τb = 0.47, P = .01). In A. phagocytophilum seropositive neonates, it was unlikely that a positive titer would be detected by 3 months of age (OR = 0.002, P = .02, 95% CI: 0.00001‐0.38). Three out of 20 foals seroconverted between 3 and 6 months of age. Conclusions and Clinical Importance Transfer of specific passive immunity to A. phagocytophilum occurred in 80% of foals born to seropositive mares and declined by 3 months of age. A. phagocytophilum infection should be considered in foals displaying clinical signs consistent with EGA.https://doi.org/10.1111/jvim.16812colostrumequine granulocytic anaplasmosisfoalIgGmaternal immunity |
| spellingShingle | Emily K. Rule Ashley G. Boyle Darko Stefanovski Eman Anis Jennifer Linton Olivia Lorello Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern Maryland Journal of Veterinary Internal Medicine colostrum equine granulocytic anaplasmosis foal IgG maternal immunity |
| title | Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern Maryland |
| title_full | Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern Maryland |
| title_fullStr | Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern Maryland |
| title_full_unstemmed | Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern Maryland |
| title_short | Transfer of naturally acquired specific passive immunity against Anaplasma phagocytophilum in foals in Southeastern Pennsylvania and Northern Maryland |
| title_sort | transfer of naturally acquired specific passive immunity against anaplasma phagocytophilum in foals in southeastern pennsylvania and northern maryland |
| topic | colostrum equine granulocytic anaplasmosis foal IgG maternal immunity |
| url | https://doi.org/10.1111/jvim.16812 |
| work_keys_str_mv | AT emilykrule transferofnaturallyacquiredspecificpassiveimmunityagainstanaplasmaphagocytophiluminfoalsinsoutheasternpennsylvaniaandnorthernmaryland AT ashleygboyle transferofnaturallyacquiredspecificpassiveimmunityagainstanaplasmaphagocytophiluminfoalsinsoutheasternpennsylvaniaandnorthernmaryland AT darkostefanovski transferofnaturallyacquiredspecificpassiveimmunityagainstanaplasmaphagocytophiluminfoalsinsoutheasternpennsylvaniaandnorthernmaryland AT emananis transferofnaturallyacquiredspecificpassiveimmunityagainstanaplasmaphagocytophiluminfoalsinsoutheasternpennsylvaniaandnorthernmaryland AT jenniferlinton transferofnaturallyacquiredspecificpassiveimmunityagainstanaplasmaphagocytophiluminfoalsinsoutheasternpennsylvaniaandnorthernmaryland AT olivialorello transferofnaturallyacquiredspecificpassiveimmunityagainstanaplasmaphagocytophiluminfoalsinsoutheasternpennsylvaniaandnorthernmaryland |