Not realistic
Where did the rabbits come from?
10,000 rabbits is quite a lot of rabbits. Your army would need to spend a great deal of energy capturing that many live rabbits. Or your army has spent quite some time breeding rabbits and caring for them. Or you have a large force of rabbit-wranglers. Somewhere. Who are now out of work. Either way, that's not realistic.
An army on the march might trap a few rabbits, but not enough to feed the troops, and no where near enough to stockpile this sacrificial bounty. Rabbits run fast and wouldn't hang around near incoming armies, their foragers, etc.
How much blood?
Nevermind how they got the rabbits, assuming they have them... Rabbits weigh, on average, 1.2 kg1. They average 56 ml of blood per kg2. That means that if you could get 100% of the blood out of your rabbits, that's 672 liters.
But you can't get 100% out. Some will remain in the flesh. Some will stain the fur and not be usable. And much will soak into the ground. So even if your army manages to get 50% of the blood as usable ground lubricant, that's only about 336 liters. By the time you spread that around your army, it won't present any challenge to the cavalry.
How long to get the blood?
Each soldier has to kill his own rabbit. No squeamishness here. Cutting the throat and draining blood into a bucket will take at least 10 minutes per rabbit. ("Squeeze hard, lads! Get every drop!") You then have to pour each bucket into a larger vat, or pass the bucket up the line to the next guy. If you want to toss the rabbits out there, too, that'll take some more time. Oh, and this is a sacrifice. There's ritual involved. So make that 20 minutes. And you can't rush, else you botch the ritual or spill the bucket.
So now your men have to carry buckets sufficient for all this blood and wine. And not spill it. And transfer it from the back of the line to the front. I'd say you're looking at roughly an hour, minimum, not counting the time to ready the rabbits, wine, and buckets.
That's assuming the back row has 1 bucket per man. They kill the rabbit, say the words, and pour the wine, then pass their bucket up the middle line. Middle line men kill the rabbit, say the words, pour the wine and pass to the front. Front line repeats. Then they pour the buckets out, 3 paces in front of their line. If you have fewer buckets -- a reasonable guess, since buckets are not a standard field kit item -- then it takes longer.
So probably at least 3 or more hours of passing out creatures, capturing the rabbits that get dropped, passing out wine, capturing the rabbits that squirmed free, and then passing out buckets. That time would be better spent setting up spears at 45 degree angles, or honing small trees into spikes to repel their horses.
Now add the wine!
So let's assume we collect 75% of the blood and 100% of the wine (no one cheats and drinks their allotment. It's for the gods!) That gives us a total of 5,504 liters of liquid.
But how does that work out?
If you stack your men in a square of 3 rows, that means you have about 833 men on a side. That's 3,332 men on the outer line. If all the wine/blood is poured outside this line, that's about 1.65 liters of blood-wine per person on the front line.
Less than two liters of liquid. Some of that will run off. Some will soak in. And some will pool on the ground making the potential trip-hazard you are after.
Conclusion:
Horses are generally able to move over wet ground without dying3. I mean, they do it every day. I do not believe this degree of coverage will present any challenge at all to them. Wet morning grass is as dangerous as your frontage of blood-wine.
There's no way to directly threaten the army via rabbit blood and wine. Unless the gods intervene more directly4.
Better to focus on spears or spikes set at 45 degree angles to repel their horses.
4 (Yes, Richard, orbitally launched rabbit-sicles are a completely different set of questions but those questions don't really fit into the framework of this particular question...)