​Histomorphological and Immunohistochemical Studies on Ovaries of Crossbred Dairy Cows with Ovarian Hypoplasia

Abstract

Background: Anatomical abnormalities of the ovaries can be responsible for a variety of reproductive problems, ranging from subfertility to sterility. The current study was aimed to evaluate the ovaries for histological variations and for the identification of Insulin-like Growth Factor Binding Protein - 2 (IGFBP-2) by Immunohistochemistry. IGFBP-2 was produced by ovarian tissues and was subjected to dynamic changes during follicle growth, differentiation and degeneration. Methods: The study was conducted on the genitalia of 100 dairy cows / heifers collected from Meat Technology Unit, Mannuthy. Out of these 100 animals, three showed ovarian hypoplasia. Tissue samples from different regions were fixed in 10 per cent neutral buffered formalin. Standard procedures were adopted for histoarchitectural studies and samples were subjected to immunohistochemistry. Result: Hypoplastic ovaries were appeared as small, wrinkled, flattened and elongated structures. Histologically, the ovary was not demarcated into a cortex and medulla distinctly. The ovaries were mostly devoid of ovarian follicles and corpora lutea. In partial hypoplastic ovaries, higher number of atretic follicles were noticed when compared with the normal ovary. Some of these atretic follicles showed a thickened zona pellucida. The granulosa cells surrounding the oocyte were degenerated. Tissue samples from the animals with ovarian hypoplasia showed a strong immunoreaction (for IGFBP-2) in the primordial and atretic follicles. The staining intensity and percentage of immunoreactive cells was comparatively higher than that of the control group. More number of IGFBP-2 blocked the positive effect of FSH and suppress steroidogenesis. The overall percentage of positive immunoreactive cells was more than 50 per cent with strongly positive staining intensity.