A. Boos

Immunohistochemical assessment of oestrogen receptor and progesterone receptor distribution in biopsy samples of the bovine endometrium collected throughout the oestrous cycle

Abstract The study was designed to determine the distribution of oestrogen receptors (OR) and progesterone receptors (PR) in specific endometrial cell population during the oestrous cycle. Uterine biopsy samples and blood were obtained from five clinically healthy cows at Days 1 (initiation of behavioural oestrus), 8, 15 and 19 of the oestrous cycle. All animals conceived after biopsy regimen. Immunoperoxidase staining techniques at light microscopic level were used to localise OR and PR. Specific positive staining reactions for both receptors were always limited to cell nuclei. Immunoreactivity was scored semiquantitatively. In the surface epithelium, OR were detectable throughout the oestrous cycle and exhibited a significant increase from Days 8 to 15. In stromal cells and glandular epithelial cells, however, staining intensities for OR were strong at behavioural oestrus (Day 1). Significantly lower immunoreactivities were recorded at cycle Day 15. At oestrus, and to a lesser extent at Day 8, a significant gradient in oestrogen receptor content was evident, showing increasing immunoreactivity with the depth of the endometrial tissue. In surface epithelial cells, significantly more progesterone receptor immunoreactivity was evident at Day 8 as compared with Days 1, 15 and 19. In glandular epithelia, only some PR stained at oestrus, many of them occurred at Day 8 and very few could occasionally be seen at Days 15 and 19. In stromal cells, PR exhibited a somewhat different quantitative staining pattern, i.e. many occurred at Days 1, 8 and 19. A significant decrease in immunoreactivity was observed between Days 8 and 15. While occasionally recorded smooth muscle cells of the myometrium could exhibit even strong immunoreactivities for both receptors, such cells of the tunica media of blood vessels were almost devoid of OR and PR. Caruncular tissue districts, in a few cases included in biopsy specimens, did not differ substantially from intercaruncular endometrium in OR and PR contents. Endothelial cells, granulocytes and lymphocytes always were devoid of specific nuclear staining. In the present study, OR and PR contents of the bovine endometrium exhibit cell type and location specific reaction patterns during the oestrous cycle. This suggests that different cell types within this target organ can respond in a different manner to identical hormonal stimuli.

Collagen Types I, III and IV in the Placentome and Interplacentomal Maternal and Fetal Tissues in Normal Cows and in Cattle with Retention of Fetal Membranes

The increase in uterine mass during pregnancy requires the establishment of sufficient blood supply to and strong supportive elements within the uterus. These needs are correlated with the remodelling and production of ECM materials. Therefore, placentomes and interplacentomal parts of the uterine walls and adherent allantochorion were collected from 45 cows at slaughter. Additional placentomes were obtained from 5 cows at premature cesarean section and at term in 5 cows releasing their fetal membranes in time or in 5 animals with retention of the fetal membranes, i.e. in total 60 pregnancies. Unfixed cryostat sections from 4 animals per month of pregnancy and 5 animals per peripartal group (in total 51 pregnancies) were used to immunolocalize collagen types I, III, and IV by an indirect FITC method. Collagen types I and III co-localize within the uterus. The tensile strength of the pregnant uterus is mainly represented by high contents of collagen type I within the allantochorion and subepithelial endometrial and subserosal meshes. Chorionic villi are fixed within caruncular crypts by two mechanisms: crypt openings are narrow and supplied with thick edges containing collagen types I and III. Collagen type IV contributes to all basement membranes and encloses connective tissue cells within the maternal crypt stroma, the stratum compactum and the perimetrial connective tissue. At term, fetal membranes and placentomes are edematous and at the light-microscopic level no distinct differences are visible between connective tissue fibers of placentomes from animals retaining the fetal membranes and those releasing them in time. In conclusion, collagen types I, III and IV exhibit type- and location-specific distribution patterns within the uterus of the pregnant cow. These may additionally be influenced by the stage of pregnancy, thus reflecting the dynamic processes at the stromal level.

Immunohistochemical assessment of prostaglandin H-synthase in bovine endometrial biopsy samples collected throughout the oestrous cycle

The study was designed to determine the distribution of prostaglandin H-synthase (PGS) also known as cyclooxygenase in specific uterine cell populations during the oestrous cycle. Endometrial biopsy samples were obtained from a total of 10 clinically healthy cows at days 1 (initiation of behavioural oestrus), 8, 15, and 19 of the oestrous cycle. All animals conceived after biopsy regimen. Data of semiquantitatively scored immunoreactivities were analysed using analyses of variance, t-tests for paired data and correlation analyses. Biotin-streptavidin-peroxidase immunostaining technique was employed to localise PGS. Specific staining was consistently present in endothelial cells of arteries but not capillaries and venules. A gradient of staining intensity was clearly apparent within the endometrium: surface epithelial cells and stromal cells located near the endometrial surface are consistently stained more intensely than glandular epithelial cells and stromal cells lying deeper in the endometrium. Days of oestrous cycle also influenced PGS immunoreactivities. Generally, higher immunoreactivities were recorded in surface epithelium, uterine glands and endometrial stromal cells at cycle days 1 and 19 as compared to cycle days 8 and 15. Minimal scoring values were mainly found at cycle day 8. The results of the present study suggest that the amount of bovine endometrial PGS varies considerably with the day of cycle in the above mentioned cell-type- and location-restricted manner. Therefore, the capacity of the bovine uterine mucosa for prostaglandin production may--amongst other factors--depend on the cycle-restricted availability of the respective enzyme systems.

Activity of alkaline phosphatase in uterine flushings of dairy cows affected with ovarian cysts or endometritis.

Both uterine horns of 14 dairy cows with ovarian follicular cysts, and four animals affected with purulent endometritis were flushed via catheter using 30 ml phosphate buffered saline, following evisceration at a local abattori. Activity in the flushing media of alkaline phosphatase (ALP) and aspartate aminotransferase (GOT) were examined. Ovaries were prepared for light microscopy. Amount and morphological integrity of luteinized tissue found on the ovaries were reflected by correspondent levels in ALP activity, which was higher in the media taken from the ipsilateral to the luteal tissue situated uterine horns (651 +/- 228 vs 244 +/- 62 u/l, n = 3). Only cows having relatively large amounts of luteal tissue on the cystic ovaries (as in luteinized follicular cysts) exhibited very high ALP activity in uterine flushings (2693 +/- 1348 u/l, n = 2). Results suggest the existence of local relationships between luteal tissue in the ovary and the ipsilateral uterine horn in cows with ovarian follicular cysts.

Activity of Δ5-3β-Hydroxysteroid dehydrogenase, succinate dehydrogenase, and glucose-6-phosphate dehydrogenase in bovine luteinized follicular cysts and corpora lutea of estrous cycle: A quantitative histochemical study☆

Abstract Genital organs and blood samples of dairy cows were obtained from the local slaughter-house. Fourteen luteinized follicular cysts (LFC) and 20 corpora lutea of estrous cycle (CLC) were used for the quantitative enzyme histochemical demonstration of Δ 5 -3 β -hydroxysteroid dehydrogenase (3 β -OHSDH), succinate dehydrogenase (SDH) and glucose-6-phosphate dehydrogenase (G-6-PDH) activities, employing a computerized microscope photometer. Progesterone concentrations were determined in blood serum by radioimmunoassay. Luteal tissue samples were grouped in several developmental stages according to micromorphological criteria. The enzyme activities per volume unit were the same for all luteal cells regardless of their position within the cyst wall. The pattern of enzyme activities in luteal tissue was influenced by local cell composition and the fraction of steroidogenic cytoplasm in luteal tissue which varied according to the distance from the cyst cavity. In LFC and CLC, activities of 3 β -OHSDH and SDH in large (LLC) and small luteal cells (SLC) and luteal tissue, as well as relative amounts of 3 β -OHSDH-positive tissue fractions, and serum progesterone values exhibited a distinct pattern, depending on the morphological development of luteal tissue samples. G-6-PDH did not show these relations. Activities of 3 β -OHSDH and SDH were higher in LLC than in SLC. Activities of G-6-PDH, however, were distinctly higher in SLC. 3 β -OHSDH and SDH showed a positive correlation in LLC, SLC, and luteal tissue. There was no interrelation between G-6-PDH and the other enzymes tested. Enzyme activities in LLC and SLC were positively correlated. 3 β -OHSDH and SDH exhibited a positive correlation to serum progesterone concentrations, while G-6-PDH did not. The results of the present quantitative enzyme histochemical study indicate that the structural development of bovine luteal tissue of LFC and CLC is paralleled by corresponding 3 β -OHSDH and SDH activities, which, in turn, are positively related to serum progesterone concentrations. All enzymes tested are more active in LFC than in CLC, indicating a functional equivalency or almost predominance in luteal tissue of LFC compared to that of CLC. Serum progesterone concentrations, however, were lower in animals bearing LFC than in those having CLC. Since histochemical characteristics of LFC are similar to those of CLC, the results suggest that LFC regress spontaneously within a period similar to normal estrous cycle length, because no focal regeneration could be found, such as is typical for corpora lutea of pregnancy.

Osteological investigations of the incidence of cranial alterations in domestic ducks (Anas platyrhynchos f. dom.) with feather crests.

The feather crest of the domestic duck (Anas platyrhynchos f. dom.) represents a peculiar mutation of the integument of the head, which has been known since the 17th century. In literature this is described as a variety with malformations in skull and brain anatomy in which various central nervous deficiencies in affected birds are possible. Our examinations demonstrated several conspicuous anatomical alterations in the skulls of domestic ducks with feather crests. Osteophytes of different size in the hypodermis of the crest integument were found as well as cranial perforations located in the parieto-occipital region. In morphometric studies, a significant increase in the capacity of the cranium was found in Crested ducks compared to other examined breeds (Abacot Ranger, German Pekin ducks). This increase in cranial capacity in Crested ducks results from the occurrence and enlargement of a tentorial fatty depot during craniogenesis. The formation and enlargement of the fat body can influence cranium growth as long as the cranial bones are not entirely fused. Thus, in comparison to other phenotypically similar domesticated birds like the crested chicken, the expression of feather crests in domestic ducks demonstrates symptomatologic differences. In conclusion, our examinations demonstrate that the skulls of Crested ducks show various peculiar morphological alterations whose genesis is up to now not known with satisfactory accuracy. Further investigations are continuing to assertain whether there are linkages between cranial alterations (malformations of the calvaria, osteophytes, increased capacity of the cranium) and the extremely high prenatal and postnatal mortalities and numerous abnormalities described in crested breeds of the domestic duck.

Superfusion of bovine luteal tissue slices: Basic secretion, influence of LH on progesterone secretion and influence of superfusion on the preservation of the tissue

Abstract Bovine luteal tissue slices collected at different stages of the estrous cycle were superfused and progesterone secretion was measured over a period of 8 h. The average basal progesterone secretion by 1 g of tissue ranged between 200 and 800 ng/ml medium and remained stable for 8 to 12 h after an adaptation phase of 1 h. There was no difference in the hormone secretion of tissue slices collected at different stages of the estrous cycle. Slices of luteal tissue removed from five animals on days 12 13 of the cycle were stimulated with different doses of luteinizing hormone (LH) (0.1, 1,10,100, 1000 ng/ml). The mean progesterone secretion increased to 604 ± 45,607 ± 50, 878 ± 107, 756 ± 112, and 766 ± 117 ng/ml, respectively. The hormone secretion of control samples (0 ng LH/ml medium) was 443 ± 25 ng/ml. With an LH dosage of 10 ng/ml and more, the difference as opposed to the control values was statistically significant (P ⩽0.01). Histological and histochemical examination of the luteal tissue prior to and after the superfusion experimental revealed degenerative alterations in the central areas of the tissue slice. Peripheral parts of the tissue, however, were not affected to the same extent. Our results suggest that superfusion within a period of 8 to 12 h represents an appropriate method for the analysis of progesterone secretion in bovine luteal tissue slices.

Ontogeny and occurrence of the corpus fibulae in the domesticated goat (Capra aegagrus f. hircus).

Osteological characteristics are often used to identify animal species in a cheap and rapid manner. In this context it is believed that the corpus fibulae of the goat is represented by a tight cord of connective tissue--the so-called ligamentum fibulare. The results of the present morphometric study indicate, however, that in nearly 60% of the 143 examined animals, the corpus fibulae is a pin-shaped flattened piece of bone which may additionally be accompanied by a pyramid-shaped bone lying closely to the caput fibulae. The length of the corpus fibulae increases with age and varies greatly between individuals but its centre is located close to the border between the proximal and the intermediate third of the tibia. The cartilaginous fetal anlage is either transformed to bone or catabolised during fetal live. Desmal ossification should play an important role in the growth of the corpus fibulae since no cartilage could be detected in kids and adult goats.

Morphogenesis of the osteo-architecture in the carnassial region of the feline mandible, as demonstrated by microfocal radiography

For the first time, osteogenesis was observed using direct magnifying microradiography, a noninvasive technique that has a high power of resolution. Thus, it was possible to correlate different stages of bone maturation in the feline mandible with specific functional demands. Our observations suggest a relationship between osseous structure and the mode of feeding and content of the diet.