not taking anything out of context, just stating that infact land animals that do eat other animals are halal and gave the example of a chicken. so there is more to it than just the statement. no argument here, just further elaboration so you and everyone else can think about it 
secondly, if parasites are present in herbivores and then the herbivores are eaten by a carniovore and I eat the carnivore I get parasites, well I would get parasites by eating te herbivore as well since the herbivoe has parasites.
Now if the point is more about toxic buildup, then there can be a point, however in that case fish eat smaller fish and at each level the toxins build up and it is an issue.
just having a discussionm we can agree, we can disagree, we can debate issues, question..etc etc. No harm no foul mon ami