Utilização da ultra-sonografia para diagnosticar alterações uterinas em cabras, gestação, perdas embrionária-fetal e sexo fetal em ovelhas

Abstract

Four experiments have been performed to evaluate the efficiency of ultrasound to detect precocious uterine alterations, pregnancy and sex of the fetus in goat and sheep. The first study determined the incidence of hydrometra and mucometra in Saanen, Alpine American, Boer and Anglo-Nubiana breeds submitted to ultrasound examination to detected early pregnancy using linear (6.0 and 8,0 MHz) and micronconvex (5.0 and 7,5 MHz) transducers. The females that showed uterine liquid or mucus were examined 15 days later to confirm the pathological state and treated with 0.5 mg prostaglandin that did not present estrus. Out of the 143 females examined, 63 (41.9%) were pregnant, 67 (51.6%) were non-pregnant, 11 (6.4%) had hydrometra and 2 (1.6%) had mucometra, corresponding to an incidence of 11%. Moreover, out of the 13 treated females 100% were pregnant. It was concluded that ultrasound is an important tool to detect uterine alterations and that prostaglandin is an efficient treatment for hydrometra and mucometra. The second study tested the viability transrectal linear (6.0 and 8.0 MHz) versus transvaginal micro-convex (5.0 and 7.5 MHz) ultrasound transducers for pregnancy diagnosis in Saint Ines sheep (n = 145). In Group (G) I females (n = 30) were between 15th to 29th days of gestation, in Group II (n = 28) were between 30th to 59th days, in Group III (n = 35) were between 60th to 89th days, in Group IV (n = 32) were between 90th to 139th days and Group V (n = 20) was formed by non-pregnant females. The average time, in seconds, to accomplish the pregnancy diagnosis using either transrectal or transvaginal method was 9.02±5.57 and 11.74±7.06 in GI, 13.90±16.49 and 11.37±12.19 in GII, 56.07±41.21 and 128.33±66.23 in GIII, 5.37±3.40 and 2.69±1.90 in GIV and 14.27±17.60 and 20.35±18.17 in GV, respectively. The transrectal examination was faster (P<0.05) in GI, GIII and GV and slower in GIV and equal (P> 0.05) in GII. It was concluded that pregnancy diagnosis in sheep can be carried out through both methods considering the accessibility, however, the transrectal method was suggested to be faster. In the third study Saint Ines sheep was used to determine the efficiency of ultrasound to evaluate embryonic-fetal development, especially to determine the date of first sign of pregnancy. Sixty pregnant sheep 15th to 45th days of gestation were subjected to ultrasound using a linear transrectal transducer with double frequency (6 and 8 MHz). The identification of earliest and the latest parameters of evaluation were performed between days 15th to 19th (16.7±1.3), day for intra-uterine fluid. The presence of embryonic vesicle was determined between days 16th to 22th (18.6±1.4), day of embryo between 18th to 26th (22.8±1.9), placentoms between days 20th to 29th (25.1±2.0), heartbeat between days 24th to 29th (25.9±1.4), amniotic membrane between days 24th to 32th (27.4±1.8), head and upper body differentiation between days 30th to 37th (33.4±2.2), fetus movement between days 30th to 38th (34.2±2.0), umbilical cord between days 32th to 39th (35.1±1.5), button of the anterior and posterior members between days 34th to 39th (36.7±1.5), ocular globe between days 39th to 43th (40.9±1.2). These results allowed to conclude that the first signs of gestation can be identified as soon as day 15 days of gestation. However, it is wise diagnose pregnancy after day 24 when it is possible to visualize the fetus and the heart beat. In the fourth study the objective was ultrasound during the initial phase of pregnancy to determine embryonic and fetal losses and to identify the sex of the conceptus of Saint Ines sheep. The females (n = 132) were examined in the 30th day to confirm pregnancy and determine embryo viability or loss. The sex or loss of the fetus was determined on days 40th, 50th and 60th using a linear transrectal transducer (6.0 and 8.0 MHz). The sex was identified through the localization of the genital tubercle or the visualization of the external genital. Out of the 160 conceptus examined there was 10.0% (16/160) of losses, being 5.6% (9/160) during embryonic phase and 4.4% (7/160) during the fetal phase, showing no difference (P> 0.05) between both phases. In single gestation there was less conceptus losses 3.9% (73/76) (P< 0.05) which occurred between days 40th and 50th day as well 50th and 60th. One concludes that the ultrasound is an efficient tool to diagnosis early gestation, to monitor embryonic and fetal loss and to identify to the sex Saint Ines of embryos from 50th day of gestation.