Right the number of total mobilised forces for period of the war(1915-1918) was 1 100 000-1 200 000.Not that we have such army in any particular moment of the war.Also these number include men that are in army service but they never enter in trenches.
And I doupt that at Dobro pole bulgarian soldiers were bare footed, hungry they were and overall morale was very low aswell.After this defeat some 9 000 troops rebeled and headed toward Sofia where they were defeated.Veterans who survived three wars were killed by their own in front of their capital.