CNAME and TTL

[sumsum 2000]

Hi,
I am having only a forward only option in bind configuration.
When i dig on some host which has CNAME, the cache contains  a longer TTL
for the CNAME than the TTL for the  final resolution of the IP.

However, in the example below, the CNAME  is  queried again when the TTL
for a336.g.akamai.net. is up.

I was expecting that the TTL for CNAME will be used from the cache and the
lookup will not happen again until the TTL has not expired.
Is there a way to avoid additional lookups when the value is already
present in the cache for CNAME entries.

root at titan# dig  emp.bbci.co.uk

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-14.mlos2.mwg <<>> emp.bbci.co.uk
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27673
;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;emp.bbci.co.uk. IN A

;; ANSWER SECTION:
emp.bbci.co.uk. 436 IN CNAME emp-live.bbc.net.uk.
emp-live.bbc.net.uk. 253 IN CNAME emp.bbci.co.uk.edgesuite.net.
emp.bbci.co.uk.edgesuite.net. 3368 IN CNAME a336.g.akamai.net.
a336.g.akamai.net. 6 IN A 58.27.124.225
a336.g.akamai.net. 6 IN A 58.27.124.200
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