Sexagem fetal em pequenos ruminantes por meio da visibilização do tubérculo genital

Abstract

The objective of this study was to verify the accuracy of sexing and fetal number estimation in small ruminants, with different numbers of fetuses, by transrectal ultrasonographic examination. Fifty-four fetuses from 36 Santa Inês sheep were evaluated. Twenty four simple pregnancies, ten double and two triple pregnancies and 23 fetuses from 11 Anglo Nubian goats were evaluated from three single pregnancies, five double, two triple and One quadruple. The evaluations were performed at 55 and 65 days of gestation, using a transrectal ultrasonography, using a dual frequency linear transducer (6.0 and 8.0 MHz). Fetal sex was diagnosed, taking into account the location of the genital tubercle or the visualization of the external genitalia. The experimental design was completely randomized. The accuracy of the diagnosis of fetal sexing was evaluated using the Chi-square test (X2) and the normality test used was Shapiro-wilk, both considering a 5% significance level. The gestational period interfered (P <0.05) in the accuracy of fetal sexing in both species. In the caprine species, the sexing accuracy was 64.71% on the 55th day of gestation and 100% on the 65th day. In the ovine species, 82.61% and 95.83% accuracy were obtained for the 55th and 65th day of gestation, respectively. Fetal sex did not interfere (P> 0.05) in the sexing accuracy, in both species, during the evaluated periods, nor was it influenced (P> 0.05) by the type of gestation. The accuracy of the diagnosis for fetal number estimation was 75.0%, 80% and 100% for single, double and triple pregnancies, respectively on the 55th day of pregnancy and 100%, 83.33% and 100% on the 65th day Of gestation in the caprine species. For the ovine species, the precision was 88.89% and 96% in the simple gestations, 70% and 90% in the double and 100% and 100% in the triples, for the diagnoses performed on the 55th and 65th day of gestation, respectively. Thus, B-mode ultrasonography is an efficient method to perform early diagnosis of fetal sex and to determine the number of fetuses in the small ruminants on the 65th day of gestation, in addition, the accuracy of fetal sexing is not influenced by the type Gestation or fetal sex.