Open Access
Research (Published online: 19-08-2023)
15. Longitudinal humoral immune response and maternal immunity in horses after a single live-attenuated vaccination against African horse sickness during the disease outbreak in Thailand
Nutnaree Kunanusont, Machimaporn Taesuji, Usakorn Kulthonggate, Khate Rattanamas, Thanongsak Mamom, Kosin Thongsri, Thawijit Phannithi, and Sakchai Ruenphet
Veterinary World, 16(8): 1690-1694

Nutnaree Kunanusont: Clinic for Horse, Faculty of Veterinary Medicine, Mahanakorn University of Technology, 140 Cheum-Sampan Rd. Nong Chock, Bangkok 10530 Thailand.
Machimaporn Taesuji: Clinic for Horse, Faculty of Veterinary Medicine, Mahanakorn University of Technology, 140 Cheum-Sampan Rd. Nong Chock, Bangkok 10530 Thailand.
Usakorn Kulthonggate: Clinic for Horse, Faculty of Veterinary Medicine, Mahanakorn University of Technology, 140 Cheum-Sampan Rd. Nong Chock, Bangkok 10530 Thailand.
Khate Rattanamas: Department of Immunology and Virology, Faculty of Veterinary Medicine, Mahanakorn University of Technology, 140 Cheum-Sampan Rd. Nong Chock, Bangkok 10530 Thailand.
Thanongsak Mamom: Department of Pathology, Faculty of Veterinary Medicine, Mahanakorn University of Technology, 140 Cheum-Sampan Rd. Nong Chock, Bangkok 10530 Thailand.
Kosin Thongsri: Department of Veterinary and Remount, Division of First Livestock and Agriculture, The Veterinary Hospital, Royal Thai Army, 57 Koh Samrong Subdistrict, Mueang District, Kanchanaburi Province 71000 Thailand.
Thawijit Phannithi: Department of Immunology and Virology, Faculty of Veterinary Medicine, Mahanakorn University of Technology, 140 Cheum-Sampan Rd. Nong Chock, Bangkok 10530 Thailand.
Sakchai Ruenphet: Department of Immunology and Virology, Faculty of Veterinary Medicine, Mahanakorn University of Technology, 140 Cheum-Sampan Rd. Nong Chock, Bangkok 10530 Thailand.

doi: 10.14202/vetworld.2023.1690-1694

Article history: Received: 13-04-2023, Accepted: 10-07-2023, Published online: 19-08-2023

Corresponding author: Sakchai Ruenphet

E-mail: rsakchai@hotmail.com

Citation: Kunanusont N, Taesuji M, Kulthonggate U, Rattanamas K, Mamom T, Thongsri K, Phannithi T, and Ruenphet S (2023) Longitudinal humoral immune response and maternal immunity in horses after a single live-attenuated vaccination against African horse sickness during the disease outbreak in Thailand, Veterinary World, 16(8): 1690-1694.
Abstract

Background and Aim: African horse sickness (AHS) has become a newly emerging disease after an outbreak in northeastern Thailand in March 2020. Mass vaccination in horses with live-attenuated AHS virus (AHSV) vaccine is essential for AHS control and prevention. This study aimed to monitor the longitudinal humoral immune response before and after a single vaccination using a live-attenuated vaccine against AHS in stallions, mares, and pregnant mares, including maternal immunity in foals born from pregnant mares during the outbreak in Thailand.

Materials and Methods: A total of 13 stallions and 23 non-pregnant and 21 pregnant mares were vaccinated with live-attenuated AHSV vaccines. Serum samples from selected horses were collected on the day of vaccination and 1, 6, 8, 9, 10, and 12-months post-vaccination. Furthermore, seven serum samples of foals born from vaccinated pregnant mares were collected on parturition date and 1, 3, and 6-months old. The antibody titer against AHS in all collected serum samples was evaluated using a commercial enzyme-linked immunosorbent assay kit. All data were analyzed for mean and standard deviation for each group of samples using a spreadsheet program. Antibody titers between times were analyzed using a one-way analysis of variance as repeated measurement, and antibody titers between horse groups were analyzed using a general linear model for statistically significant differences when p < 0.05.

Results: In stallion and non-pregnant mare groups, there were no statistically significant differences in antibody titers in all 6 time periods after vaccination. The antibody titer in the pregnant mare group showed a non-statistically significant difference between each gestation stage, except at 8 months post-vaccination. Furthermore, increasing antibody titers on days 1 and 3 after receiving colostrum in foals indicate the major role of transcolostral antibody transfer for AHS.

Conclusion: This study demonstrated that a single AHS vaccination using a live-attenuated vaccine could stimulate high antibody titers sufficient for AHS control and prevention during the outbreak in Thailand. Similarly, the antibody response of vaccinated horses of both genders, including various stages of pregnant mares, was statistically not different.

Keywords: African horse sickness, antibody, maternal immunity, stage of gestation, vaccination.