Hey,
I find that with new charges, the best way to get them feeding on a regular schedule, is to allow them the first week or so (7-14 days), to adjust and acclimate; make no attempt at feeding. (Feeding trials can begin after the adjustment period).
However, if you feel you have the confidence to begin feeding trials sooner, that of course is pretty discretionary, and can take place at any time during the acquisition of your blood. I sometimes do begin feeding trials a few days after first receiving an animal and have even fed some successfully on their first day in their new home.
My preferred method for feeding new animals, is to offer food from a pair of 12 inch forceps. The food is offered at night, when the feeding response is most likely to be at its highest. The food is warmed up in a small container using hot water, if it is a frozen thawed mouse and is then presented to the snake with the head of the animal first. Sometimes the snake will sniff around the food item first before grasping it, or it will grab it immediately. The idea is to be able to release the food as quickly as possible with little to no hesitation as this can startle the snake and can cause it to drop it. Sometimes tapping the snake with the food gently on its nose, after it has shown some interest in the food will elicit a feeding response.
Make sure that the food is always warmed up enough, as bloods and short-tails, will zero in on the heat and will target the heat source, using scent as a secondary que.
If the snake is in its hide box, you can offer it food in front of the opening of the hide box with the forceps and hold it there while you wave the food in front of the hide spot and tap the opening gently with the mouse to attract its attention. If all is well, and the snake has been made to feel secure in its new home, it should strike and redraw along with the mouse into its hide with the food.
Also, it is important that the lights in the room be dimmed as they do not like to feed (with exceptions), when the lights are too bright. Albeit, a great feeder will feed at anytime of the day with lights dimmed or off. If feeding from forceps does not work, try placing the food in front of the hide spot opening and leaving it there over night. Even placing the food half into its hide with the rear portion of the mouses body sticking out of the box will work.
Be sure to feed when the room is quiet and with as little distraction as possible. Always use fresh food!
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"Until we lose our self, there is no way of finding our self."
-Henry Miller.