Yeah looks like salt water. Have seen large lakes and salt water. I'm five minutes from the ocean. Used to live right on the ocean. You could hear the waves at night and the smell the ocean.
I wonder if this is someplace in Africa or Asia and these aren't domesticated cattle. They might be Bantengs, which live in Asia, Java, and Borneo. They have similar horns.
when I was a young-un
people would swim their cows across to the beach for the winter
I never saw them do it but they did