Alvin F. Weber

Structural changes in the nuclear body in the adrenal zona fasciculata of the calf following the administration of ACTH

The nuclear body was studied in parenchymatous cells of the adrenal zona glomerulosa and zona fasciculata of untreated calves of both sexes, of male calves which had been given only ACTH, and of male calves given ACTH and simultaneously subjected to sodium depletion by means of a unilateral parotid fistula. The nuclear body was observed to show structural and positional changes exclusively in the zona fasciculata, apparently in specific response to ACTH administration, leading to the development of a multilocular body. The latter body consisted in general of several single- or double-walled locules or large vesicles which often were collectively enclosed in a singular encompassing membrane. In the course of development the multilocular body was found to move from the vicinity of the nucleolus toward the nuclear membrane and in some instances to become contiguous with it. The nature and possible function of the nuclear body is discussed.

Nuclear Bodies: Their Prevalence, Location, and Ultrastructure in the Calf

Nuclear bodies, averaging 0.8 to 1.2� in diameter, were observed in various parenchymatous and interstitial cells of the calf. They were most prevalent and complex in structure in the parenchymatous cells of the adrenal cortex, and consisted of a fibrillar outer portion and a central or core area of varying size that was composed of electron-opaque particulate matter. These bodies, as far as the authors are aware, are of unknown significance.

Electron microscopic studies of the distal border of the canine olfactory epithelium

The structure of the distal border of the olfactory epithelium from 25 normal adult dogs of various breeds was studied with the electron microscope. Sections of vesicles of olfactory cells were found to contain 6–16 characteristic cilia; it is estimated that a total of 100–150 olfactory cilia are probably present on each cell. The basal corpuscles of the cilia contained two accessory structures, namely the basal feet and the cross-striated rootlet fibers. The rootlet fibers consisted of a striated bundle of several fine, closely adherent filaments. Microtubules and multivesicular bodies were found in the olfactory cells. The supporting cells were easily recognized by their unique bushy microvilli, electron opaque cytoplasmic organelles, and smaller-sized multivesicular bodies. In addition to the usual supporting cell type, an apparent fourth cell type was observed. It contained short, sparse microvilli. This cell type was easily identifiable by the presence of a more electron translucent cytoplasm, and was postulated to be a precursor of the usual supporting cell type.

Ultrastructural studies of the bovine graafian follicle and corpus luteum.

SummaryOvaries were obtained from normal adult dairy cows at all days of the estrous cycle. The largest Graafian follicle and corpus luteum were excised and prepared for electron microscopic study.In the follicle wall, membrana granulosa cells contained granular endoplasmic reticulum and mitochondria with villous or lamellar cristae. The theca interna cells during proestrus and estrus contained ribosomes separated from endoplasmic reticulum. The latter during these periods assumed tubular and tortuous shapes. Mitochondria during these periods assumed rounded shapes, were occasionally cup-shaped, and developed tubular cristae.In the corpus luteum, the large luteal cells during metestrus and diestrus contained an abundance of agranular, tubular, branching membranes of endoplasmic reticulum and Golgi apparatus. Mitochondria were large, with tubular cristae, but smaller mitochondria, with irregular or villous cristae, were also present. ‘Transitional bodies’ of the latter mitochondria to another form were observed. Cup-shaped and annular mitochondria were present during diestrus. In the small luteal cells, large vesicular membrane formations were present and often associated with lipid bodies. The cells were lipid-laden. Lysosomes and granular bodies were present during luteal regression.The observed features of the granulosa cells are related to protein synthesis, those of the pre-ovulatory theca interna cells and metestrus-diestrus large luteal cells to steroid synthesis, and those of the small luteal cells to lipid storage.

Qualitative and quantitative morphological studies of the cells of the membrana granulosa, theca interna and corpus luteum of the bovine ovary

SummaryOvaries from normal adult dairy cows were obtained at all days of the estrous cycle. The largest Graafian follicle and corpus luteum were excised, prepared for light microscopy, examined morphologically, and quantitations of nuclear sizes were made using a planimetric technique.During the 3–4 days before ovulation, membrana granulosa cells ceased growing in size, and their nuclei decreased in size and frequently appeared pyknotic. Theca interna cells during this time formed two populations: large epithelioid cells with round nuclei, that enlarged significantly, and smaller fibroblast-type cells with spindle-shaped nuclei, that did not enlarge. During the 3–4 days after ovulation, the membrana granulosa cells of the ovulatory follicle and their nuclei enlarged significantly and contributed to the “large luteal cell” population of the corpus luteum. The spindle-shaped theca interna cells of the ovulatory follicle assumed rounded shapes and, together with some paraluteal and trabecular luteal cells (both, probably, of theca externa origin), contributed to the “small luteal cell” population of the corpus luteum. The epithelioid theca interna cells of the same follicle dispersed into the ovarian stroma. Eosinophils and mast cells were commonly observed among the theca cells during this time.The observations are interpreted in relation to periestrual ovarian hormone synthesis. It is suggested that the epithelioid theca interna cells during proestrus and estrus may secrete estrogens and that the large luteal cells during diestrus may secrete progesterone.

XY sex-reversal syndrome in the domestic horse

The XY sex-reversal syndrome occurs when a phenotypic mare is born that has the karyotype of a stallion. The syndrome is manifested by both genotypic and phenotypic heterogeneity. The sex-reversed genetic condition occurs frequently within certain pedigrees where XY females have been found and can be readily detected by chromosome karyotyping. The phenotypic spectrum ranges from the feminine mare with a reproductive tract that is within normal limits to the greatly masculinized mare. Pedigree analysis suggests that there are two modes of inheritance: (1) an X-linked recessive or autosomal sex-limited dominant transmitted through the female and (2) an autosomal sex-limited dominant or a Y chromosomal mutation with variable expression transmitted through the male. The proportion of female to male progeny of the 69 top-producing Arabian stallions in the world is 53 to 47, indicating that the occurrence of genetic defects affecting the sex ratio such as the XY sex-reversal syndrome is relatively infrequent. In nine cases where the sex ratios of stallions deviated significantly from the expected sex ratio, the incidence of female infertility also increased. Cytogenetic screening of young animals would provide for early detection and avoid the expense and disappointment of continuous breeding attempts. Just as importantly, it would aid in the reduction and the possible elimination of this genetic condition from breeding herds.

Quantitative ultrastructural analysis of the follicular and luteal cells of the bovine ovary

SummaryOvaries were obtained from normal adult dairy cows at all days of the estrous cycle. The largest Graafian follicle and corpus luteum were excised, prepared for electron microscopic study, and their cell components quantitated using the linear scanning method and the counting of membrane crossings.The results indicated that in the theca interna cells during proestrus and estrus and in the large luteal cells during late metestrus and diestrus, enlarged mitochondria occupied an increased cytoplasmic percentage volume. During proestrus and estrus in the theca interna cells, the concentration of membranes of endoplasmic reticulum and Golgi apparatus also increased. The cytoplasmic percentage volumes of lipid bodies and of lysosomes increased in the small luteal cells; during luteal regression, they also increased in the large luteal cells. Similar rates of increase during follicular maturation, and decrease during luteal regression, occurred for measurements of succinic dehydrogenase and mitochondria.The quantitative observations were related to the production of steroid hormones by the ovary, and to the cyclic growth and regression of follicular and luteal cells. It was noted that an increased cytoplasmic percentage volume of mitochondria, an increased concentration of agranular cytoplasmic membranes, and low levels of lipid bodies and lysosomes, were generally present at times when ovarian steroid elaboration and cell growth were maximal.

X trisomy in an Airedale bitch with ovarian dysplasia and primary anestrus

A 79,XXX chromosome complement was detected in a four-year-old Airedale Terrier bitch examined for primary anestrus. Serum concentrations of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were markedly elevated. Ovaries contained solid epithelial cords and large masses of interstitial cells but lacked follicles and corpora lutea. Somatic abnormalities were not observed. X trisomy is reviewed in six species in which it has been described.

Left Cranial Vena Cava in a Horse

A complete left cranial vena cava (LCVC) was found in a normal horse. The LCVC was well developed, but there was a complete absence of the right cranial vena cava. The azygous vein was normally distributed on the right side of the thoracic vertebral bodies but passed ventral to the aortic arch to empty into the cranial vena cava on the left close to the origin of the aortic arch. The LCVC passed over the dorsal aspect of the left atrium to reach the coronary sulcus on the caudal aspect of the heart. The LCVC opened into the right atrium via a 5 cm diameter orifice (orifice of coronary sinus). The vena cordis magna joined the LCVC 6 cm from the orifice of the coronary sinus. Complete dissection of the horse revealed no other developmental abnormalities. This case is compared with similar cases in the literature.

A chromosomal reciprocal translocation (1q+; 14q−) in a boar siring reduced litter sizes

In our initial cytogenetic surveillance of boars one of 15 was found to be hypoprolific. It averaged 7.1 piglets per litter in over 51 monospermic matings with sows which, with other boars averaged 10.8 piglets per litter. Cytogenetic evaluations revealed only the hypoprolific boar to have an abnormal karyotype, namely {38XY, t(1;14) (q2.12, q2.2)}. This represents a new type of 1;14 reciprocal translocation, and also the first report of a reciprocal translocation for swine in the United States.