Some of the reviews indicate that the cows on the trail are a problem, but I think that's mostly the perspective of people who don't spend much time around cows. The cows are almost entirely on the Buena Vista half of the trail, if you are walking the half between Lexington and the Interstate 81 overpass, you're not going to see any cows. But if you walk the other half of the trail, you'll walk past some big, photogenic bovine beauties. Just enjoy the scenery and keep moving.
Cows are large, and can be intimidating, so I understand the natural inclination to be wary of them. Here's the thing: If you don't intentionally mess with or bother the cows, you're not likely to have any problem with them. Cows are naturally a little afraid of people and will move out of your way when you approach. If a cow is laying down, it might stay where it is. Just step slightly off the trail and keep going. A spooked cow can be dangerous because they'll jump and run in random directions to try to get away from whatever has spooked them. The secret is to not sneak up on them, talk and laugh and let them hear you coming. Don't intentionally try to upset them, justkeep moving in an nonthreatening manner as you pass them, and you'll find that walkers and cows can enjoy the trail together without any problem.
Yes, there is a lot of cow manure on the Buena Vista half of the trail. This is a "nature trail." Manure is natural. Watch where you're going and you'll be able to navigate around and over the manure without any problem.
There are a number of gates that cross the trail as you pass through private farm land. Each gate is outfitted with a ladder, turnstile, or small pedestrian gate to allow easy passage for trail walkers. On my walk today I passed by some of the owners of the private farmland, working with their animals. I smiled and waved, they smiled and waved back. A little courtesy goes a long way, and is generally well received.
Just treat this trail as you would any other, don't litter, be respectful of the land, and enjoy the scenery ... cows and all.