Mighty Tyrannosaurus rex was evidently one sick puppy

       Tyrannosaurus rex and its close relatives suffered from the potentially life-threatenin disease trichomonosis, which is still carried by pigeons, a study published on Wednesday showed.
       Some of the world's most famous T rex specimens, such as "Sue" at the Field Museum in Chicago and the specimen at the Carnegie Museum of Natural History in Pittsburgh, have holes in the lower jaw, which is a classic symptom of trichomonosis, the study by a team of US and Australian researchers showed.
       "The holes in tyrannosaur jaws occur in exactly the same place as in modern birds with trichomonosis," says Ewan Wolff, a paleontologist from the University of Wisconsin-Madison who worked on the study.
       "The shape of the holes and the way that they merge into the surrounding bone is very similar in both animals."
       Trichomonosis is carried mainly by pigeons these days, but they are generally immune to the disease. Birds of prey are particularly susceptible to trichomonosis if they eat infected pigeons.
       Palaeontologists previous thought the holes in T rex were caused by tooth gouges or bacterial infections, but according to the study, which was puvlished in the peer-reviewed open-access PLoS ONE, the position and nature of the holes indicate that the dinosaur had a trichmonosis-typre disease.
       The disease appeared to be quite common in tyrannosaurs and could have been deadly to those that were infected.
       "As the parasites take hold in serious infections, lesions form bone. As the lesions grow, the animal has troble swallowing food and may eventually starve to death," says Steve Salisbury of the University of Queensland.
       Researchers have found no other dinosaurs that had the disease, and believe it was spread between tyrannosaurs by biting or even through cannibalism.