Table 1.

Summary of the clinical signs, the specific bacterial loads of CSF, and the histopathological lesions in the brain found in piglets post-infection with S. suis ST7 (piglets 17, 24, and 43) and ST2 (piglets 4, 5, and 34).

Animal Number	Symptoms post-infection	Bacterial CFU per ml of CSF	Histopathological findings
Meningitis-free animals1
17	Day 1: 40.4°C fever Day 2: no fever	None	No fibrinous or purulent lesion in the brain, meninges, or CP
24	Day 1: 41.1°C then 40.4°C fever Day 2: 40.7°C fever, which cleared by the end of the day	None	No fibrinous or purulent lesion in the brain, meninges, or CP
43	Day 1: 41.1°C then 41.3°C Day 2: 41.3°C, which cleared by the end of the day Day 14: 40.3°C, which cleared by the end of the day	None	No fibrinous or purulent lesion in the brain, meninges, or CP
Animals suffering from meningitis2
4	42.1°C fever, ataxia, kyphosis, body tremors, abdominally reinforced breathing	3.33 × 107	Moderate multifocal fibro-purulent meningitis and moderate multifocal plexus chorioiditis
5	41°C fever, ataxia, body tremors, convulsions	5.43 × 107	High grade multifocal fibro-purulent meningitis and moderate multifocal plexus chorioiditis
34	41.7°C fever, body tremors, abdominal reinforced breathing, nystagmus, opisthotonus	3.03 × 107	Moderate multifocal fibro-purulent meningitis (no comment on the state of the CP)

¹Piglets were euthanized after observation of 23 days following the experimental ST7 infection.

²Piglets were euthanized for predefined animal welfare reasons if a high fever persisted (at least 40.5°C), along with apathy and/or anorexia over a 36 h time period or if severe clinical signs, such as opisthotonus, convulsions, inability to rise, or acute polyarthritis were presented.