RG Live WotLK 3.3.5a

https://www.wowhead.com/quest=654/tanaris-field-sampling#comments:id=2973:reply=438680

Just finished this quest and I can happily report that they've finally nerfed it. Seriously nerfed. The first of each type of beast dropped the required sample and the quest log said 'complete'. Went back to the NPC and was able to hand it in. Will probably take about two minutes to complete, now. Strangely, they haven't changed the quest text that says you need 8 of each sample.

https://www.wowhead.com/quest=654/tanaris-field-sampling#comments:id=2973:reply=147026

Confirmed, they nerfed the quest, though the Quest text has not been altered. You just need to kill 1-1-1 of each mobs