| It has been proved that the somatostain genetic engineering live vector vaccine could promote growth of most domestic animals in laboratory. In this study, five experiments were done to fatherly investigate the influences of the vaccine on the growth and reproductive performance of swine in five aspects, which including the immune dosages, immune age, pig breeds, carcass quality and sows. It has made significantly foundations for the development and application in pig production.1, Immune dosages: Ninety-six three-way crossbred [Yorkshire × (Landrace × Yorkshire)] finishing pigs, with weight of 30kg, were randomly divided into 4 groups each with 24 pigs. In group A B C and D, the pigs were immunized with different dosages of somatostatin genetic engineering live vector vaccine, 4.8 × 10~7PFU per pig(Group A), 2.4 × 10~8PFU per pig(Group B), 1.2× 10~9PFU per pig(Group C) and physical salt water (Group D). Their weights were measured on the day before immunization and on 90 days post immunization. Feed intakes were also measured during the experiment. The results showed that the mean increase rate of weight per pig in Group B was 11.5%, which was significantly higher than those in other groups. The feed to gain ratio in Group B was 3.37, which was less than those in other groups. It indicated that the vaccine could promote the growth and feed efficiency of finishing pigs. The immunizing dosage of the vaccine was 2.4 × 10~8PFU per finishing pig.2 Immune age in finishing pigs: Twenty-four three-way crossbred [Yorkshire× (Landrace × Yorkshire)] finishing pigs at age of 60, 75, 90, 105, 120 days were respectively assigned to experiment group and control group (12 finishing pigs for each group). They were inoculated with somatostatin genetic engineering live vector vaccine (experiment group) and physical salt water(control group). Their weights were measured on the day...
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