Study On The Fetal Growth And Development Of Jianzhou Daer Goats(Capra Hircus)

Jianzhou Daer goat is a kind of meat goat breed which selected from the crossing generation of Nubian goat and the local Brown goat, which has characteristics like similar size and appearance, grow fast, good meat production performance and meat quality, high reproductive performance, strong stress resistance, et al, and can adjust to the south subtropical humid climate and feeding-and-management condition of our country. In order to have a deep insight into the laws of Jiangzhou Daer goat's fetal growth development, and guide the raising management work in its gestation period and birth date, which can provide a reference of Jiangzhou Daer goat's early breeding. This experiment took the fetus of Jiangzhou Daer goat as a research object, firstly observed its appearance changes, then measured the weight and length of the fetus. We measured the weight of visceral organs at the age of 60,75,90,105.120,135 and after birth 3 days. Moreover, we measured their primary muscle tissues from the fetus of 90.105,120. and 135 days respectly, analyzed their fiber diameter of the longissimus dorsi and semitendinosus. The main results are as follows:1.Jianzhou Daer goat's fetus have the basic forming at the age of 45 days firstly, when we could observed their heads, limbs and tails, secondly the matured ears and hoofs appeared at the age of 90 days, thirdly at the age of 105 days the body covered with hair, in the end the bodily form were closed to the newborn lambs at the age of 135 days.2.The average weight of Jianzhou Daer goat's fetus was 6.17 g at the age of 45 days, when the age was after birth 3 days, the average weight of Jianzhou Daer goat's fetus was 2958.64 g. The speed of ponderal growth got to the peak during the age of 105 to 120 days and the average daily gain could be as high as 58.34g.Meanwhile, the average body length of Jianzhou Daer goat's fetus was 5.38 cm and 48.68 cm at the age of 45 and after birth 3 days. The increasing of its body length was mainly concentrated in the days before 120, where its body length was 82.69% of the length at 3 days after birth, thus the period of the age from 105 to 120 days was the cross point of the rapid growth phase of body weight and length.3.Its heart, liver, lung, and kidney developed a little early and were relatively mature, grow rather quickly from the days of 105 to 120. Spleens and lungs developed lately and were relatively matured, and the dynamiting was mainly sustained after the age of 120 days. The effects of sex on internal organs of the Jianzhou Daer goat'fetus were mainly concentrated in the days after 120, and the visceral organ weight of ram was higher than ewes.4.The fastigium of the fetus of Jianzhou Daer goat's muscle growth was mainly concentrated from 90 to 120 days, when the longissimus muscle, gluteal muscles and quadriceps became matured relatively early than the supraspinatus, infraspinatus muscle, semitendinosus and adductor. Except semitendinosus, gender showed significant difference to the muscle tissue weight after the age of 105 days(P<0.05).5.The thickening of the fetus of Jianzhou Daer goat's longissimus dorsi and semitendinosus was mainly happened from the days of 105 to 120.