Foaling Patterns at Two Standardbred Studs in the Southern Hemisphere

Aims: The aim of this study was to examine the foaling patterns of Standardbred mares foaling outdoors at studs at latitude 45 degrees south. 

Methods: Data were collected prospectively by stud masters at 2 commercial Standardbred studs, generating 222 reproductive records and 439 foaling records. Data were transcribed, recorded into a customised MS Access database and examined for normality; descriptive statistics were performed using SPSS v17 (SPSS Inc, Chicago, Illinois, USA). 

Results: The average gestation length was 349 ± 10 days. Service date and foaling date both had a significant effect on gestation length (r2 = 0.598 and r2 = 0.248, P<0.001) with gestation length decreasing with later service or foaling dates. The timing of the parturitions was bimodally distributed with the primary peak around 02.00 h and a secondary smaller peak (29% of all foalings) around 13.00 h. [...]