Sex differentiation in goat fetus

Reproduction in domestic animals, as a major source of food and other products for human, has great importance and study of related subjects including sex differentiation and gonadogenesis during fetal life can solve many questions on normal development and various disorders of urogenital system. Since studies on sex differentiation in goat fetus are scarce, this study was performed. Twenty-five goat fetuses with 5-40 mm crown-rump lengths [CRL] were obtained from slaughter-house and fixed in 10% formalin solution immediately. The development and features of external genitalia of these fetuses as well as their sex differentiation were then examined. In externally indifferentiated fetuses, the cranial half of the body was cut away at the diaphragmatic level and serial sections, 6-micron thick, were prepared and the ovarian and testicular differentiation was studied. Results showed that considering the development of the external genitalia, external sex differentiation occurs at 31 mm CRL in male fetuses and at 33 mm CRL in female fetuses. Microscopic studies suggested that testicular tissue differentiation occurs at 23 mm CRL with formation of tunica albuginea and medullary cords. Ovarian tissue differentiation occurs at 38 mm CRL with establishment of cortical and medullary regions

Morphological and histometrical studies of lymphatic patches of buffalo large intestine in different ages

The objectives of this investigation were to describe the distribution, morphological structure and determination of the gut-associated lymphatic tissue [GALT] area in the buffalo large intestine where it is the site of damage in many diseases like bovine virus diarrhea [BVD], colitis and colonic infection. The macroscopic results showed that buffalo large intestine contained two lymphatic patches: A- ileocecal lymphatic patch [ICLP] which was located at the ileocecal entrance and it has an elliptical shape. B-colonic lymphatic patch [CLP] which was located in the proximal loop of ascending colon with tongueform, fingerform or crownform shapes and it was placed 24.99 +/- 1.27 cm distal to ICLP. The average elevation of ICLP was increased significantly up to 3-year-old but it decreased in 3-5-year-old [P<0.05], which indicates the beginning of the regression in ICLP. The area of ICLP was increased significantly from 6-12 months [8.6 +/- 3.96 cm[2]] to 3-5-year-old [17.4 +/- 9.13 cm[2]], [P<0.05]. The elevation of CLP was less than ICLP and did not show any significant differences in the elevation of CLP in different ages. The average area of CLP patches was increased with the age. In buffalo, like cattle, there were two types of lymphatic nodules: the propria nodules and the lymphoglandular complex. In propria nodules, lymphatic follicles were mainly in the lamina propria and in the lymphoglandular complexes, the lymphatic follicles were almost completely located under the muscularis mucosa. The number and diameter of lymphatic follicles of ICLP were more than CLP. The number and diameter of lymphatic follicles were decreased in two types of patches by age but more interesting finding was observation of more significant regression in CLP with the age