Variations of the Extensor Digitorum Brevis Muscle in the Dog

The variation of the extensor digitorum brevis (EDB) muscle was examined in 113 hindlimbs of dogs. Four types were discriminated in this muscle. Of the three heads of the muscle, the medial head went to the 2nd digit in types I and II, and to the 2nd and 3rd digits in types III and IV. The middle head went to the 3rd digit in types I and IV, and to the 3rd and 4th digits in types II and III. The lateral head went to the 4th digit in all the types. Type II was the most common of the four (78.76 %). Type III was found in 8.85%, type 1 in 973% and type IV in 2.66%.     

Intercalated duct cells in the chicken pancreatic islet with special reference to the alloxan administration.

The intercalated duct cells were observed in the A and B islets of the chicken pancreas. These cells adhered with each other by intercellular junctional complexes at the apical side. They had many microvilli projecting into the lumen. Abluminally, they displayed extended slender cytoplasmic processes between islet endocrine cells. Administration of alloxan resulted to denser cytoplasm and a more prominent thickening of cytoplasmic processes of the intercalated duct cells, although the blood glucose levels did not show appreciable changes by the treatment. The intercalated duct epithelial cells appeared clearly as stellate cells. The lysosomes increased in size and number with passage of time after alloxan administration. The present findings may suggest that intercalated ducts are not only anatomically important as a structure passing through the islet but also play physiologically by protecting the islet endocrine cells.     

Binocular Dissecting Microscopic Studies on the Density of Toruli Tactile in the La Mancha Goat

The Merkel cells and associated nervous terminal plates have been called toruli tactiles (TT). These structures can be ubiquitously seen on the shaved hairy skin after staining with a methylene blue solution. Four La Mancha goats of both sexes were examined for the density of TT. TT were visually located under a binocular dissecting microscopic (14x) and then the number of TT in the field was directly counted. The density of TT in different corporal areas of the body surface was estimated from the mean of several two-cm square samples of skin. The results obtained are as follows: The mean number per two-cm square on the whole body surface ranged from 10.06-11.36 in the male specimen and from 12.98-14.32 in the female specimen. The density of TT was rather high in the temporal and buccal areas, on the neck, chin and cranial breast, and on the lateral surface of the arm, thigh and leg. Density was moderate in the fronto-parieto-occipital area (female), on the loin and buttocks, in the upper costal, lower caudo-costal, xiphoid-umbilical and umbilical-pubic areas, and on the lateral surface of the forearm. TT were absent or very few in number on the nose and chin, the scrotum, caudal-pubic area of males, the udder, the vulva, and the digitorum manus et pedis.     

Histological Studies on the Endocrine Pancreas in the Dog

Based on histological structure and cellular formation, the endocrine pancreas (pars endocrina pancreatis) (PEP) or pancreatic islet (insulae pancreaticae), was divided into two types in the dog. One type of PEP was the islet of Langerhans. In the glandular lobule, the islet was surrounded by exocrine acini. The other type of PEP, in general, exhibited a feature of a neuro-insular complex. It was found within the interlobular connective tissue of the pancreas. This type of PEP was attached to a nerve bundle or ganglion. In the pancreas of the immature dog, a large population of endocrine cells was recognized to form a blood islet within the neuro-insular complex.     

Density of Toruli Tactiles in the Japanese Monkey

Two Japanese monkeys of both sexes were examined for density of Toruli tactiles (TT) on the shaved skin stained with methylene blue solution. Each Torulus tactilis was located by the aid of a binocular loupe and marked with white lacquer. The distribution of marked TT was estimated by a mean of TT per 2cm square (2CS) of skin on the body surface. The results obtained are as follows. The mean per 2CS on the entire body surface was approximately 8.7 in the female specimen and approximately 10.0 in the male specimen. The density of distribution of TT was highest in the temporal and buccal areas, on the neck, loins and the dorsal and lateral surfaces of the arms and forearms. Density was moderate in the parieto-occipital and gluteal areas, the back, the ventral surface of the cranial half of the trunk and the lateral surface of the thigh. Density was low, to near absence in the circumanal area, on the nose, upper eyelids, cars, ischial callosities, external genitals, palms and soles.     

Early organogenesis of the caprine stomach

Early organogenesis of the caprine stomach was studied in a series of 11 embryos ranging from 6.5 mm neck-rump length (NRL) to 13.3 mm crown-rump length (CRL). In embryos with 6.5-6.7 mm NRL, a part of the primordial proper esophagus extended to the dorsal side of the primordial stomach. The primordial proper esophagus and its extension were lined with a simple epithelium and stained dark brown with Con A III, while the primordial stomach was weakly stained. In embryo with 7.3 mm NRL, the esophageal extension was separated from the proper esophagus by constriction, and became a primordial forestomach situated in an area outside the omental sac. In embryos with 8.3 mm NRL-10.7 mm CRL, primordial forestomach and primordial stomach were united and formed a spindle shaped primordial ruminant stomach with foregut rotation. The primordial ruminant stomach was similar to the primordial simple stomach except that it was more flattened laterally with the convex at the area of 'lesser curvature'. Primordial rumen, omasum and abomasum appeared from the spindle shaped primordial ruminant stomach in an embryo with 12.9 mm CRL. In an embryo with 13.3 mm CRL, primordial reticulum originated from an area between the primordial rumen and omasum.