What is the difference between homologous and heterologous immunoglobulins?

Homologous immunoglobulin is the human (from the similar species) immunoglobulin. In case of inoculation in animals as in veterinary procedures homologous immunoglobulin is that from the blood of animals of the similar species of the animal undergoing treatment. Heterologous immunoglobulin is that obtained from animals of dissimilar species from the individual into which it will be inoculated.

The homologous immunoglobulin is safer as it is collected from beings of the similar species of the individual in which it will be inoculated and thus the risk of the antibodies to be known as foreign and to trigger an immune response is lower. Heterologous immunoglobulins are more prone to being destroyed by the own antibodies of the individual.