If they are Windows XP you can do the following:
wmic /node:@serverlist.txt /namespace:\\root\SecurityCenter path AntiVirusProduct get /value
for Vista+:
wmic /node:@serverlist.txt /namespace:\\root\SecurityCenter2 path AntiVirusProduct get /value
That will run wmic against all of the servers in the serverlist.txt file
And if you need a powershell way of doing it, check here: http://blog.powershell.no/2011/06/12/use-windows-powershell-to-get-antivirus-product-information/
Here is the reference for the state of the AV product from the powershell script linked above. You can use this to make sure the AV is installed (if a server comes back with "No Instance Available"), enabled and up to date.
"262144" {$defstatus = "Up to date" ;$rtstatus = "Disabled"}
"262160" {$defstatus = "Out of date" ;$rtstatus = "Disabled"}
"266240" {$defstatus = "Up to date" ;$rtstatus = "Enabled" "Consolas">}
"266256" {$defstatus = "Out of date" ;$rtstatus = "Enabled"}
"393216" {$defstatus = "Up to date" ;$rtstatus = "Disabled"}
"393232" {$defstatus = "Out of date" ;$rtstatus = "Disabled"}
"393488" {$defstatus = "Out of date" ;$rtstatus = "Disabled"}
"397312" {$defstatus = "Up to date" ;$rtstatus = "Enabled"}
"397328" {$defstatus = "Out of date" ;$rtstatus = "Enabled"}
"397584" {$defstatus = "Out of date" ;$rtstatus = "Enabled"}