Abstract:
Consumer discrimination against meat products from animals treated with hormones has provided the impetus to investigate alternative ways of boosting feed conversion efficiency and growth rates of animals and to manipulate the reproductive capacity of animals. In view of the longevity of the immune response to specific antigens and the realization that antibodies are capable of neutralizing or mimicking the actions of hormones, vaccination techniques have been explored as alternatives to hormone administration to boost animal productivity. To date, only two commercial vaccines are available to improve the efficiency of production, although neither is related to the stimulation of growth efficiency: Fecundin (registered product, Glaxo Pty Ltd) is designed to improve lambing percentages, and Vaxstrate (registered product, Arthur Webster & Co.) to prevent reproductive activity. In this review, recent advances in vaccine development are explored together with some of the problems encountered in research in this field.