Infectious laryngotracheitis (ILT) is an acute respiratory disease of poultry caused by gallid alpha herpesvirus I (GaHV-1) commonly recognized as Infectious laryngotracheitis virus (ILTV). Prevention and control of the disease is built on biosecurity and vaccination. Particularly, chicken embryo origin (CEO) vaccines have proven to be the most protective vaccines against the disease. However, it has been demonstrated that CEO vaccines have inherent virulence which is easily triggered if the vaccine is allowed to circulate in naive or poorly vaccinated flocks. Also, the CEO vaccines establish latency; therefore, vaccinated birds carry the virus for life and under stress the vaccine virus can be reactivated. In recent years, the use of recombinant ILT vaccines has significantly expanded as it offers a safer vaccination alternative for the control of the disease. However, experimental evidence has shown that recombinant Herpesvirus of turkey Laryngotracheitis (rHVT-LT) vaccines induce partial protection because under challenge with virulent strains, virus replication still occurs in the trachea of vaccinated chickens. In order to better understand the role that the dose of rHVT-LT vaccine plays in protection; whether rHVT-LT vaccinated chickens can transmit virus after challenge, and how the combination of rHVT-LT and CEO vaccines benefit the control of ILT, the objective of this work was threefold: 1) To evaluate the protection efficacy of a rHVT-LT vaccine when administered at standardized doses of 6000, 3000 and 1000 plaque forming units (PFUs) and the effect of the rHVT-LT vaccination in transmission of the challenge virus to contact naive chickens; 2) To evaluate the replication and protection efficacy of a rHVT-LT vaccine when administered at a double commercial dose (13000 PFU); and 3) To evaluate the effect of rHVT-LT vaccination in CEO replication and how this vaccination strategy enhances protection and limits challenge virus transmission to contact naive chickens. Independent of the rHVT-LT vaccine dose, vaccinated chickens showed significant reduction in clinical signs, maintained body weight gain after challenge, and lessened the challenge virus replication. However, despite reduction of challenge virus replication in the trachea, challenge virus was transmitted from rHVT-LT vaccinated chickens to contact naive chickens, whereas in CEO or rHVT + CEO vaccinated chickens transmission of the challenge virus to naive chickens was impeded. Finally, it was concluded that priming with rHVT-LT reduced CEO virus replication and the addition of a CEO vaccination provided a more robust protection than rHVT alone.