INFLUENCE OF IMMUNONEUTRALIZATION OF SOMA TOSTATIN ON TURKEY GROWTH AND BODY CONFORMATION

Male and female birds were randomly divided into groups of 20 each. Th e first group (20 males, 20 females) consisted of experimental birds w hich were immunised at 5, 26, 54 and at 76 days of age using a conjuga te of cyclic somatostatin (SRIF 28, M.W. 1638,12 CSAV UOCHAB Prague, D r. Barth), and bovine serum albumin (BSA) emulsified in a complete Fre und adjuvant (cF.A.). Birds were immunised with 350 mug SRIF/1 kg five weight in 0.5 volume of inoculum and injected subcutaneously at 10 si tes on the lower part of the distal end of the wing. The second group (20 males and 20 females) consisted of control birds which received 0. 5 ml cF.A. at the same age, applied in the same manner. Body weight wa s measured at weekly intervals. In week 14 a carcass analysis was perf ormed in half of the turkey hens from both groups. Carcass evaluation was made in the remaining birds in week 18. Besides total carcass weig ht, weights of breast, leg muscles, abdominal fat and sizes of breast and leg bones were recorded. Turkey hens immunized against SRIF achiev ed better weight gain during fattening period (Fig. 1). An increase in weight gain was observed after the second immunization with SRIF. Aft er the third immunization with SRIF (54 days) weight gain was 170 g. T he difference in weight gain was significant after the fourth immuniza tion with SRIF in week 12 (P<0.01). At this point the difference in we ight was 535 g(10,5 %)in favour of the experimental group. From week 1 4 to the end of the experiment (week 18) a gradual equalization of wei ght differences between the groups was observed. Active immunization a nti somatostatin had similar effects in both males and females. Howeve r, the effect was less strong in male turkeys, and weight differences between the control and experimental were detected around week 9, i.e. , after the third round of immunization (190 g). The highest weight di fferences were recorded at the end of the observation period, when imm unized males were 450 g heavier than the males in the control group. L ive weight differences between groups were reflected in the weights of the main parts of the carcass of both male and female birds (Tab. I). In week 14 carcass weight of both female groups was similar (5180 g f or control and 5160 g for experimental group). However, significant di fferences in breast muscle weights were observed in this period (Tab. I). The breast muscle of immunized turkey hens was 151 g heavier than that of the control turkey hens (P<0.05). These differences expressed in relative values (breast muscle weight/carcass weight x 100) were al so statistically significant (P<0.01). Higher breast muscle weight in experimental turkey hens was also recorded in week 18. Weights of othe r body parts did not show any absolute or relative differences (Tab.I) . In week 18 immunized toms were 500 g heavier than their control coun terparts in week 18 (8754 g versus 8252 g). Half of this weight accoun ted for differences in the breast muscle, which was statistically heav ier (P<0.05) in the experimental group (Tab. I). The share of the brea st muscle from the total carcass weight was 1.5% higher in the experim ental group than in the control group (P<0.05). There were no absolute or relative differences in other parts. Relatively higher growth of t he breast area in experimental groups is also confirmed by the length of sternum in comparison with measurements of other skeletal parts (Ta b II). In week 14 experimental turkey hens had longer sternum (+0.6 cm ) and its ossified parts (+1.3 cm) (P<0.01). No changes were observed in the length of other skeletal parts in both experimental and control groups (Tab II).