Number 3 is ideal, but 2 and 4 are fine, too.  This article is from October 31, 2013 THE SCOOP ON POOP from THE SIGHTHOUND SIDE OF LIFE
First, it’s perfectly normal for your new Sighthound — permanent pack member or foster pup — to have mushy poop for the first couple of days. Normal mushy can just be part of the adjustment period. To help get things on the right track, here are a few of our tried and true methods:
• a spoonful of canned pumpkin with each meal. (You can substitute butternut squash, but don’t use pumpkin pie filling!)
• a bit of bland rice or well cooked pasta added to each meal of kibble.
• a probiotic, such as Fortiflora.
If number 5 turns into 6 or 7 or lasts for more than three days, contact your vet. Your vet may recommend withholding food for a day and then using over-the-counter Imodium to firm things up. For the average Greyhound, one capsule twice a day is useful.
If things still don’t get firm after all the above, it’s time for to bring in a sample to your vet. It’s quite common for hookworm, among other parasites, to linger in a dog’s intestines even after one or even more treatments. Panacur is a safe, inexpensive de-wormer . . . but you may have to add it to you dog’s food for up to seven days depending on the parasite and then still need to repeat the process in two weeks. It’s an inconvenience, but important for the long term health of your dog.
If the fecal is negative, it’s time to consider a food change. While the traditional accepted method is to gradually mix in the new food as an increasing portion of your dog’s kibble over the course of a week, the purpose of that strategy is to prevent loose stools. If that ship has already sailed, you can make a faster change. We’ve found skipping one meal and then offering a half-size portion of the new food at the next meal time works pretty well. If there are no ill effects from the reduced portion, they can go back up to their normal amount of the new food at the following meal.
Many of our volunteers endorse switching to a grain-free and/or minimal ingredient food. One of our volunteers battled liquid poo for months in her ex-racer – which cleared up in one day after switching to a different kibble with a different protein source. When switching, eliminate all treats and food extras like yogurt or salmon oil just to make sure you can isolate what is causing the problem. You can add treats back after your pup is stabilized on a food that agrees with him.
Finally, the last thing you ever want to see in poop is a spot of red and we understand the panic it causes. But here’s something to put your mind at ease: A spot or couple of drops of bright red blood, especially after a bout of diarrhea, is almost always nothing to worry about. It’s the brown blood and the metallic, coppery smell in stool that necessitates a trip to the vet.
We hope this information helps and we wish nice firm poop for you and yours! And extra thick and strong poop bags for everyone!