The premier institute for veterinary research in Tamil Nadu is located in:

Chennai
Thanjavur
Coimbatore
Madurai

The correct answer is Chennai.

The Tamil Nadu Veterinary and Animal Sciences University (TANUVAS) is a state university located in Chennai, Tamil Nadu, India. It was established in 1989 by the Tamil Nadu Veterinary and Animal Sciences University Act, 1989. The university offers undergraduate, postgraduate, and doctoral programs in veterinary science and animal sciences. It also has a number of research centers and institutes.

The university has a main campus in Chennai and four regional campuses in Coimbatore, Madurai, Tiruchirappalli, and Vellore. The main campus has a number of academic and research departments, as well as a library, a hospital, and a farm. The regional campuses offer undergraduate and postgraduate programs in veterinary science and animal sciences.

The university is affiliated with a number of veterinary colleges and animal science colleges in Tamil Nadu. It also has a number of research centers and institutes, which conduct research in areas such as animal health, animal production, and animal welfare.

The university is recognized by the Veterinary Council of India and the Indian Council of Agricultural Research. It is also a member of the Association of Indian Universities and the Association of Commonwealth Universities.

The university has a strong research focus and has produced a number of research papers and publications. It has also received a number of awards and recognition for its research work.

The university is committed to providing quality education and research in veterinary science and animal sciences. It is also committed to serving the needs of the livestock sector in Tamil Nadu and the country.

The other options are incorrect because they are not the locations of the premier institute for veterinary research in Tamil Nadu.