母兔配种后10小时血清中若干生理指标与子代性比的相关

CORRELATION BETWEEN OFFSPRING SEX RATIO AND SOME PHYSIOLOGICAL INDEXES OF THE FEMALE RABBIT SERUM AT 10 HOURS AFTER MATING

测定日本大耳白兔母兔配种后１０小时血清中的１０项生理指标，并与母兔所产每窝仔兔的性比（雄性个体所占比率）进行对应分析（窝仔数＜６的数据未参与此项分析）。结果表明：母兔血清中ＦＳＨ、Ｔ（睾酮）、 Ｎａ＋和Ｍ２＋的浓度在高、低两个性比组间有显著差异， Ｔ３（三碘甲状腺原氨酸）的差异接近显著水平（Ｐ＜０．１）；并且，ＦＳＨ和Ｔ３与子代性比里显著负相关（ｒ分别为－０．５０和－０．４６），Ｍｇ２＋与子代性比里显著正相关（ｒ＝０．３９）；同时，Ｍｇ２＋／Ｃａ２＋、Ｍｇ２＋×Ｎａ＋、Ｍｇ２＋×Ｋ＋和Ｔ３×ＦＳＨ与子代性比的相关分别为０．４０、０．４３、０．３９和－０．５３（Ｐ＜０．０５）。

It has been reported that the physiological conditions of female parents before concep- tion and /or at the time of conception could influence sex ratio (SR) of offspring (percent of male). in the previous studies, we verified the conclusion of Schenk by adding glucose to the ration of female parents in mice and rabbits. And it was found that glucose having the effect of increasing female offspring could also reduce the levels of T (testosterone) of the maternal serum. The present study is presenting the relationship between some physiological indexes of female rabbit serum at 10 hours after mating and the SR of the offspring. Ten physiological indexes including FSH, LH, T, E2 (estradiol), T3 (triiodothyronine), Ins (insulin), K+, Na+, Ca^2+ and Mg^2+were used in this study. Six hormones were measured by radioim- munological assay, 4 ions were measured by atomic-absorption flame photometry. Fifty two females and 19 males of Japanese large-ear and white rabbits at 6-8 month of age were selected. Mating were completed within 4 days. Time of mating and blood collection were at 8-9 A. M. and 6-7 P.M. the day respectively. The SR of each litter was calculated. According to the SR value, the female rabbits were divided into high SR group (HSRG) and low SR group (LSRG). The corresponding data of litter size<6 and that of the median SR values (0. 63>SR>0. 38) were eliminated. The results of the t test showed that there were significant difin the level of FSH, T, Na+ and Mg^2+ between the HSRG and the LSRG. However, it was found that the LH level of the female rabbit serum was not associated with the SR of the offspring, which was different from the results of James' experiment. And it seems that the effect of FSH on the SR is not the result of male selective abortion, since there is no difference in the litter size between the 2 groups. As far as the ion concentration is concerned, there is no evidence for proving that the value of K+/(Ca^2++Mg^2+) are in relation to that of the SR. In addition, the difference of T3 concentration between these 2 groups is near the significant level (p< 0.1). Some difference of insulin concentration as well appears in 2 groups but insignificant. Furthermore, the correlation analysis, in which those data of the median SR values, which were eliminated from the above t test, were used here, indicates that the SR of the offspring shows significant negative correlations with the level of FSH and T3 (r=-0.50 and-0.46 respectively) and significant possitive correlation with the level of Mg^2+ (r= 0.39). And the correction coeffcients of the SR with Mg^2+ /Ca^2+, Mg^2+×Na+, Mg^2+ × K+ and T3×FSH are 0.40, 0.43, 0.39 and -0.53 respectively. The results suggest that there are interaction effects between the related two factors on the SR of the progeny. Finaly, by means of multiple regression, 3 factors (T3, FSH and Mg^2+) that closely related with the SR of the offspring were involved in the regression equation: SR=0.95847-0.00134T3-0.00902FSH+0.22322 Mg^2+ (R=0.7420, P<0. 01). From this study, the authors suggest that there exist coordination in some extent among those theories concerning the SR of the offspring associated with the physiological conditions of the mother.