Effect Of Inhibin Gene Vaccine Immunization On Recover Of Reproductive Performance And Lactation In Cows

Reproduction and lactation are important indicators for the evaluation of performance of dairy cattle, in order to investigate inhibit gene immunization reproduction and lactation performance in dairy cows,16Holstein cows were randomly divided into four groups (three test groups and a control group) in in the present study (four cows for each group). The three test groups of cows(one week after postpartum) were intramusularly immunized with high(5×1010CFU),middle (5×109CFU) and low (5×108CFU) dosage of inhibin C500the-pXAIS recombinant bacteria (3mL per cow), and the control group was injected with hydroxide saline (3mL per cow). Booster immunization with the same dosage as the primary immunization was performed once at4-week interval. Postpartum uterine involution and ovarian function were studied by usage of B ultrasonic diagnostic techniques. Besides changes of antibody levels, reproductive hormones such as estrogen(E2), progesterone(P4), follicle stimulting hormone(FSH) and luteinizing hormone(LH) in the plasma samples were also analyzed. In addition, the average daily milk yield and the total milk production within40days after the primary immunization were studied in the experiment.The results showed that:(1) The immune group P/N values in the three immunized groups were higher than the control group, difference was obvious for the high and middle group compared to the control group (P<0.05); the positive antibody percentage was100%one week after the booster immunization.(2) The uterine gravid horn recovery (28.75±1.92days) in the high dosage group was significantly faster than the other groups (P<0.05);(3) The average diameter of the dominant follicle in the high dosage group was higher than the other groups, and the amount of follicle waves was lower in comparison with the other groups.(4) Contents of the follicle stimulating hormones were substantially higher than the other groups during the experimental observation, follicle-stimulating hormone levels in the plasma were significantly higher than that in the control group (P<0.05) one week after the booster immunization(the fifth week after the primary immunization),; However, difference between the two groups was not signiticant for the other three kinds of hormones (E2, P4, FSH, LH) except for the similar change rules;(5) Difference among all the groups was not significant for the average daily milk yield (P>0.05), but the total milk production within40days after the primary immunization was remarkably higher than the control group (P<0.05).Immunization against inhibin gene vaccine can cause effective immune response after the booster immunization, stimulate secretion of FSH, shorten the recovery time of uterine gravid horn and improve lactation performance of the dairy cows.