1: Is index capable of being used on the slaves, or are they just making
bad decisions? Try disabling seq scans on the slave servers for testing
and see if they can use the index. Use "set enable_seqscan = FALSE;"
If they can't use the index then, then they are likely in the wrong
locale, and you'll need to re initdb them to get them to use an index.
If they can use the index then we have tuning issue.