Showing papers in "Anatomia Histologia Embryologia in 1993"

Etude Morpho‐Structurale des Papilles Linguales chez le Buffle (Bubalus bubalis)

Abstract: Summary Morphostructural characteristics of lingual papillae in buffalos The morphostructural characteristics of lingual papillae in 30 adult buffalos were studied by SEM. In this species, dorsal lingual surface papillae shos different shape so that their classification is complicated. Topography and morphology of conical and vallate papillae presents significant aspects. Particularly, the conical papillae have a different morphological organization when they are localized over the side of the tongue apex or over dorso-lateral tract of the tongue body. The functional aspects are discussed.

Gross Anatomy of the Canine Portal Vein

Abstract: The gross anatomy of the portal vein of 21 dogs was studied by venous portography, corrosion casting, and gross dissection. The portal vein in all specimens originated by confluence of the cranial and caudal mesenteric veins. Its large tributaries were the splenic and gastroduodenal veins, which entered the portal vein between its origin and the hepatic porta. At the hepatic porta, the portal vein divided into a short right branch and a larger left branch. The right branch ramified in the caudate process of the caudate lobe and in the right lateral lobe of the liver. The left branch was essentially the continuation of the portal vein from which successive branches passed to each of the remaining lobes of the liver and the papillary process of the caudate lobe.

The anatomy of the cloacal bursa (bursa of Fabricius) in the helmeted guinea fowl (Numida meleagris galeata).

Abstract: The cloacal bursa (bursa of Fabricius) in the guinea fowls appeared either as an oval blind sac with a short thick stalk in one group or had a pointed cranial blind end with a slightly bulging middle part that was followed by a thick caudal stalk in the other group. Both groups of bursae originated from the proctodeal wall of the cloaca and were placed dorsal to the rectum. The average length of the bursa was 18 mm while the average width at the mid section was 15 mm. The internal surface showed about 12-14 primary folds. Histologically, the outline of the bursa was well established by day 18 of incubation. The primary folds had also been formed. Lymphocytes had already been encountered within the framework of the bursa at this day. The epithelium bordering the tunica propria was composed principally of two layers of cuboidal cells. Epithelial buds had also formed and some were already detached from the epithelial lining. The blood vessels present were positioned just beneath the outer covering. At day 19 of incubation, most of the epithelial buds had two layers of cells arranged in a circumscribed manner while a few had three layers of cells. Blood vessels had increased in number and were deeper placed inside the bursa than previously. At day 20, the cells of the upper layer of the epithelium were dorsoventrally flattened and stained paler than the cells of the lower layer. It was possible to distinguish the cortex from the medulla and the basement lining between both zones was distinct. Tiny vesicles within the cytoplasm of the epithelial cells at the mucosa and follicles were observed. Macrophages were also observed within the gland. At day 21, blood vessels were observed in the cortex of the follicles. The maximum number of primary folds (14) had been formed. At day 22, several follicles had severed connections with the mucosal epithelium. The mucosal lining had dropped to a single layer of cells in some areas. Goblet cells were observed amongst the mucosal cells. A plasma cell had first appeared. By day 25, dead cells had increased quite in number and there was also an increase in number of medium and small-sized lymphocytes within the gland. By day 26, the upper layer of the surface epithelium was composed primarily of tall columnar cells with numerous large vacuoles. Macrophages had suddenly increased within the thin interfollicular spaces and most of them were crowded internally with various sizes of debris.(ABSTRACT TRUNCATED AT 400 WORDS)

Retinal Photoreceptor Fine Structure in the Red‐Tailed Hawk (Buteo jamaicensis)

Abstract: The retinal photoreceptors of the red-tailed hawk (Buteo jamaicensis) consist of rods, single cones and double (unequal) cones present in a ratio of about 2:1:5. In the light-adapted state, the rods are slender elongated cells with outer segments that reach to the retinal epithelial (RPE) cells. The inner segment displays an ellipsoid of mitochondria, plentiful polysomes, some rough ER and Golgi zones. The rod nucleus is located deep within the outer nuclear layer and the synaptic spherule displays both invaginated (ribbon) and superficial (conventional) synaptic sites. Single cones show a thin tapering outer segment, a large electron lucent oil droplet at the apex of the inner segment and an ellipsoid of mitochondria. Double cones consist of a larger chief member which displays a thin tapering outer segment and an electron dense oil droplet as well as a smaller accessory cone which shows no oil droplet, an ellipsoid and a paraboloid of glycogen. As in the single cone, polysomes, RER and Golgi zones are also noted in the inner segments of both members of the double cone. Near the external limiting membrane the chief and accessory cones show membrane specializations indicative of junctions on their contiguous surfaces. All cone photoreceptors are of a smaller diameter than is normally reported for avian species. Both single and double cones display several invaginated synapses as well as numerous superficial synaptic sites.

Use of monoclonal antibodies for immunohistochemical study of bovine spleen on frozen sections.

Abstract: Summary Many monoclonal antibodies reactive with bovine leukocyte differentiation antigens are now available. Immunohistochemical staining on frozen sections using these monoclonal antibodies permits study of the functional morphology of bovine lymph nodes. Our study confirms usually accepted notions (B and T dependent-zones) and supplies complementary data about the repartition of CD4 cells (particularly intrafollicular positive cells), yb T cells, MHC II expression and dendritic leukocytes.

Intramuscular Distribution of Fibre Types in the Gluteus Medius of the Horse: A Histochemical Analysis

Abstract: Summary The results from a recent study by Bruce and Schurg (1990) indicate that the gluteus medius (Gm) of the horse is a complex muscle subdivided by an internal tendinous sheet into two regions (dorsal and ventral) which may subserve different functions. In the present study, both regions were found to contain a similar proportion of histochemically-determined muscle fibre types. Fibre type composition did not generally vary over the length of the muscle at the same relative depth. In contrast, there was a significant tendency for the percentage of type I fibres to increase gradually in accordance with depth. These histochemical results do not suggest that the two regions of the Gm assume distinct functional roles; they do, however, indicate that at a given relative depth the muscle fibre type distribution is relatively uniform over the length of the muscle. Nevertheless, care should be exercised in sampling and interpreting data obtained from limited biopsy of equine Gm, due to the substantial histochemical variation of fibre type compositon as a function of sampling depth.

Regularities and irregularities in the structure of the seminiferous epithelium in the domestic fowl (Gallus domesticus). I. Suggestion of the presence of the seminiferous epithelial cycle.

Abstract: A cellular association demarcated by two perpendiculars which were drawn between adjacent bundles of elongate spermatids from the tubular lumen to the basement membrane, was made the unit of histometrical observation in this study (provisionally called a "column"). Cell counting revealed that the average numbers per column of various types of germ cells do not show any significant differences among 5 fowls and between paired testes. The frequency of spermiogenic steps (numbered 1-8) was investigated in each column. A definite and common pattern was found in the frequency distribution in the 5 fowls observed. A relationship between spermiation and younger spermatid steps was also investigated in each column. The spermiation was found at different steps, but most frequently at step 2 (30.6%). Based on these observations and referring to other author's information, an average time interval between two successive spermiations was calculated roughly at 3.3 +/- 1.2 days. Theoretically, this value is equal to an average length of one epithelial cycle. Such a variable cycle may have caused irregular cellular associations in this species.

Veränderungen der Muskelfasertypenverteilung im M. longissimus dorsi von Ebern während des Wachstums, dargestellt mit verschiedenen histochemischen Methoden

Abstract: Summary Changes in the distribution of muscle-fiber-types from the M. longissimus dorsi of male pigs. A Histochemical Approach Samples of the M. longissimus dorsi from growing up pigs were taken by a shooting-biopsy. The types of muscle-fibers could be demonstrated by two different histochemical staining procedures. With these two histochemical staining procedures significant differences between the different structure of the muscle-fibers during increasing age of the pigs could be detected.

Loads on Muscles, Tendons and Bones in the Hind Extremities of Sheep – A Theoretical study*

Abstract: Muscle forces and bending moments were calculated with a two-dimensional non-linear force and moment analysis (according to the Finite Element Method) during the foot-lowering phase, stance phase and stem phase in the hind legs of sheep. During the foot-lowering phase, the largest production of force is detectable in the m. biceps femoris and the highest bending moment in the proximal third of the metatarsal bone. The lowest influence of force resulted during the stance phase. During the stance phase, high forces are detectable only in the patellar ligament and middle-high forces in the m. flexor digitalis profundus. In contrast, bending forces are almost equal in strength in the metatarsus and tibia. The strongest forces are detectable in the m. quadriceps femoris and extreme demands of the patellar ligament as well as of the flexors in the proximal ankle joint during the stem phase.

Anatomical Studies on the Spinal Cord Segments of the Impala

Abstract: Summary The anatomy of the spinal cord segments was studied and recorded for the impala. The root attachment lengths were greatest at C3, T10 and L3 cord segment levels in the respective regions. As to the root emergence length the greatest lengths were observed at C7, T]0> L5 and S1 cord segment levels respectively. The interroot interval was longest at C2, T8 and L1 segments respectively. The longest cord segments were C2, T13, L2 and S2 segments. The widest cord segments of their respective regions were C7, T1, L5 and S1 cord segments. As to segment volume C3, T13, L2 and S1 were the most voluminous cord segments in the respective cord regions. Statistical analysis revealed a high correlation among all of the study parameters suggesting a high degree of multicolinearity. Gross anatomical relationships concerning the location of the spinal cord segments with respect to the vertebrae were studied. The cord segments C], Ts–T4 and Li–L3 were within their vertebral limits. In the impala the spinal cord terminated at the midlevel of S4 vertebra.

Ultrastructure of the rete testis in the cat (Felis domestica, L.).

Abstract: Summary The rete testis (RT) in the cat comprises three distinct and sequential parts: septal or adlobular; mediastinal and tunical parts. This last part is followed by the small extratesticular rete testis. The whole of the RT tubules and/or channels is lined by single low columnar and/or cuboidal epithelium with ultrastructural peculiarities of secretory and absorptive functions. The Golgi apparatus polarity (cis-trans surfaces), its relation with the long profiles of the ER, mainly with the rough ER, and presence of apical uncoated electrondense granules are suggestive of active release of macromolecules, probably glycoproteins. The absorptive function is proposed through the observation of a conspicuous microvacuolar-vesicular apical complex in epithelial cells. Moreover spermatozoa phagocytosis is also noticed, mainly in the septal part of the RT.

The structure of the harderian gland of the guinea fowl at embryonic and post embryonic stages.

Abstract: Summary The Harderian gland of the guinea fowl is a bright, pink and relatively large orbital organ situated at the ventromedial aspect of the orbit. It possesses a single duct that has its exit on the convex medial surface. The outline is irregular with its caudal half narrower than the rostral half, and possessing a slight constriction about the mid point. Histologically, the gland had been outlined with the existence of a large contorted lumen by day 18 of incubation. The surface epithelial lining showed two layers of cells all through and lymphocytes were also present. By day 19 of incubation, certain zones of the surface epithelium had become pseudostratified and some of these cells contained vacuoles indicative of secretory materials within their cytoplasm. By day 21, few definitive acini with lumina had been observed and at day 23, the epithelium had assumed only a single layer of cells that were tall columnar cells, except at the junctions of the folds. By day 24, the tunica propria seemed to have completely disappeared with the acini occupying every available space. Plasma cells were seen three days after hatching.

Liver histology of Reindeer calves during the winter season

Abstract: Summary Seventeen reindeer calves were divided into three groups and liver biopsies were taken during the winter. Group 1 consisted of 6 animals allowed to graze freely under natural conditions, those in groups 2 (n = 5) and 3 (n = 6) were kept in pens and fed with lichens, the diet being designed to achieve a slight (group 2) or moderate (group 3) weight loss. Weight losses from November to April averaged 14.9%, 13.2% and 24.8% in the three groups respectively. The relative volumes of the different structures in the liver were determined by light microscopic morphometry. The mean size of the hepatocytes was slightly greater in March than in January in groups 1 and 2, and slightly smaller in group 3 (no statistical differences) and then decreased markedly. These changes could also be seen in the sinusoidal lumina. The decrease in the size of the hepatocytes may reflect a shortage of amino acids in the cells or it may be hormone-mediated. Unlike the situation in cows, there was no fatty accumulation in the hepatocytes. This may be a species adaptation to an annual period of starvation.

The Arterial System of the Wood Mouse, Apodemus sylvaticus: The Pelvic Region

Abstract: Summary In this paper we describe the origin, arrangement and variations of the major pelvic arterial trunks in the wood mouse, Apodemus sylvaticus. Seventy-six specimens have been analyzed by injection of coloured latex solution through the left ventricle of the heart and subsequent dissection of the pelvic region. Measurements of the origin of the major arterial trunks have been performed taking into account the number of anterior and posterior branches arising from its origin. Only the values of the internal iliac artery and the pudendoepigastric trunk show significant differences according to the number of previous branches. In general terms, the pattern of the pelvic arteries in the wood mouse agrees with those reported to for other rodent species. Nevertheless, some differences have been detected, especially in the origin of the major arterial trunks and the constitution of the internal iliac

Adrenal renin is localized in lysosomal granules.

Abstract: Summary Both renin and cathepsin B were co-localized in identical granules of adrenocortical cells. At day 16 of gestation, many renin-containing granules were observed and gold particles showed homogeneous intragranular distribution; whereas, those for cathepsin B was distributed heterogene-ously. At day 18 of gestation, renin immunoreactivity was decreased or undetectable, whereas cathepsin B was still demonstrated at the same level as on day 16 of gestation.

Ultrastructure of developing and mature caprine leukocytes.

Abstract: Summary Transmission electron microscopy demonstrated that, based on the structural uniqueness of the granules, caprine granulocytes are easily distinguishable from each other from the promyelocyte stage onwards. The neutrophils had the smallest granules which varied in size and were, in mature cells, either spherical to dumb-bell in shape; in mature cells the granule contents were compact and finely granular. The primary granules were smaller than the secondary granules. The eosinophil granules were large and typically had internal crystalloid structures; a second group of spherical granules with moderately coarse non-crystalloid sub-structure was present in smaller numbers in promyelocytes and myelocytes only. The basophil granules were also large, lackes crystalloids but showed variation in coarseness of granule substance, ranging from finely granular to markedly coarse. Mature granulocytes lackes Golgi apparatus and rough endoplasmic reticulum and ribosomes which were present in promyelocytes, myelocytes, metamyelocytes and bands. The monocytes had moderate numbers of spherical granules, rough endoplasmic reticulum, mitochondria and ribosomes, as well as prominent Golgi apparatus, and the cytoplasm had many small vacuoles.

Histochemical identification of the striated muscle of the canine esophagus.

Abstract: Summary Histochemistry on the cervical, thoracic, and abdominal esophageal muscle of immature, young, and adult normal dogs revealed type IIA striated musculature in contrast to some other species. No other types or subtypes were observed. This suggests that esophageal muscle type is established at birth and does not vary or that any variation has been completed by 4 weeks-of-age unlike some canine limb musculature.

The Anatomy of the Omasum of some Zambian Game Species

Abstract: Summary The gross anatomy of the omasum of 11 different Zambian game species are described. These include Roan Antelope, Sable Antelope, Wildebeest, Kudu, Kafue Lechwe, Puku, Reedbuck, Impala, Bushbuck, Oribi and Duiker. Lamellar area and papilla density and shape are reported.

The laterocranial fascia structures in the upper and forearm and the differences in the insertion of the M. biceps brachii in domestic mammals

Abstract: Summary Structures of the laterocranial Fascia in the Upper- and Forearms of Domestic Mammals, including Differences in the Aponeuroses of the M. biceps brachii The laterocranial fascia of the upper arm and forearm, as well as aponeurotic relationships of the Musculus biceps brachii were investigated on each of ten forelimbs from horses, cattle and swine. Ten canine biceps were also investigated. Equine and bovine fascia contain elastic components. An as-yet undescribed ligament-like aponeuroses of the laterocranial forearm fascia to the Fossa radialis humeri was seen in all three species studied. The laterocraniale fascia of the upper and forearm form a common passage for the Musculi hrachialis et extensor carpi radialis. In the case of the horse, the ulnar aponeurotic tendon of the biceps muscle crosses below the Ligamentum collaterale cubiti medialis. In cattle, on the other hand, it runs between the two branches of the collateral ligament, to attach on the olecranon. This portion of the equine tendon protrudes into the joint. It has connective tissue character in young animals, but becomes fibrocartilaginous in older horses. The radial aponeuroses of the canine biceps exhibits two branches. A situation similar to that seen for the ulnar aponeuroses of the equine Musculus biceps brachii is observed on the inside surface of the porcine Ligamentum cubiti mediate, in which a wedge of connective tissue protrudes into the joint, taking on fibrocartilaginous character in older animals.

Branching Mode of the Middle Rectal Artery from the Prostatic Artery in the Dog

Abstract: Summary The branching mode of the middle rectal artery from the prostatic artery was studied by gross dissection in 50 male dogs. The prostatic artery arose at the level of the lst-3rd sacral vertebra from the internal pudendal artery, and gave off the ductus deferential and the middle rectal arteries, and supplied the prostate. The middle rectal artery ran caudally along the pelvic peritoneum, and supplied the rectum ampulla. The branching mode of the middle rectal artery could be classified into four types. Nineteen cases on the right side and 22 cases on the left side showed that the middle rectal artery was a first visceral branch of the prostatic artery. Fifteen cases on the right side and 11 cases on the left side showed that it was a second visceral branch of the prostatic artery which gave off the ductus deferential artery as its first visceral branch. Nine cases on the right side and 7 cases on the left side showed that it arose at the prostatic artery ramifying at the surface of the prostate. Seven cases on the right side and 10 cases on the left side showed that it arose at the urethral branch of the prostatic artery.

Regularities and irregularities in the structure of the seminiferous epithelium in the domestic fowl (Gallus domesticus). II. Co-ordination between germ cell associations.

Abstract: It was investigated in the domestic fowl, whether a mechanism for a synchronous start of the proliferation of the differentiating spermatogonia in a transversely cut seminiferous tubule (called the "co-ordination" between germ cell association) operates effectively in this species. A trapezoid-shaped cellular association demarcated by two perpendiculars from the tubular lumen to the basement membrane was the unit of observation (provisionally called a "column" Each column is composed of a bundle of elongate spermatids and the neighbouring, various types of germ cells). The extent of closeness of the co-ordination was examined in a total of 2,650 columns, based on the continuity of the spermiogenic step-number of the youngest generation of spermatids within adjacent columns. In no case did all columns in a tubular cross section show the same-step spermatids. In most cases (50.2% of 2,650 columns), the same number was kept in only 2 to 6 adjacent columns. The arrangement of different but consecutive numbers (e.g., 1-2-3 or 1-2-1) was observed in a total of 882 columns. The co-ordination mechanism, therefore, is considered to work, albeit incomplete, among a limited number of adjacent columns in this species.

Influence of Adrenalectomy on the Developing Rat Thymus During Peri‐Weaning Period

Abstract: Summary Adrenalectomy of 17-, 18- and 19-day-old male and female rats did not cause any changes in the weight of thymus 4 days later. Adrenalectomy on day 20 of age induced a significant hypertrophy of the thymus 4 days later. These results indicate that on day 20 of age, just before weaning, the thymus is under some inhibitory regulation by the adrenal gland.

Changes in the Peritoneum during the Development of the Testis, Epididymis and Ductus Deferens in the Pig

Abstract: Summary The development of the peritoneal folds of the testis, epididymis and ductus deferens of the pig prior to testicular descent was studied in 18 to 82 days-old embryos/fetuses. The parietal attachment of the mesonephros, mesonephric and paramesonephric ducts and gubernaculum constituted the urogenital mesentery. This could be divided in a cranial and a caudal part. The first fixed the mesonephros and had a mesogonad as a secondary fold. The second had two branches, one laterally to the umbilical artery belonging to the gubernaculum (Plica gubemacularis) and the medial to the artery contained the meso- and paramesonephric ducts. The mesogonad was related caudally with Plica gubemacularis. The fold of the meso- and paramesonephric ducts could also be divided in two parts. The caudal was a primary component of the urogenital mesentery, while the cranial was first ventral and later lateral to the mesogonad (mesorchium) and appeared as a secondary fold of the urogenital mesentery (cranial part). A vascular fold contributed to separate the suspensory ligament of the testis from the developing mesorchium. The proposed meaning of the terms used might be useful for comparative studies.

Morphometric Studies on Hearts and Coronary Arteries of the Fetal and Adult Oxen

Abstract: Quantitative investigations were performed on hearts and coronary arteries of 10 fetal and 7 adult oxen. Relative heart weights were 0.42% in adults and 0.80% in fetuses. An interesting observation was that left coronary artery predominated by a ratio of 2.55 in adults and 1.41 in fetuses although the percentage of left ventricular weight was similar in both adults and fetuses. Linear regressions were also determined between ventricular weights and coronary arterial diameters.

Lectin histochemistry of glycoconjugates in horse salivary glands.

Abstract: The glycoconjugate content of major horse salivary glands was investigated by means of horseradish peroxidase-conjugated lectins. Qualitative differences were observed in the terminal sugar residues of secretory glycoproteins and glycoconjugates linked to the apical surface of excretory duct epithelial cells. Mucous acinar cells in mandibular and sublingual glands contained oligosaccharides with D-galactose, alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas mandibular, sublingual and parotid serous cells contained only oligosaccharides with terminal alpha- and beta-N-acetylgalactosamine residues. The apical portion of striated and interlobular duct lining cells of mandibular and sublingual glands stained for alpha- and beta-N-acetylgalactosamine and for N-acetylglucosamine. In parotid gland the cytoplasm of intercalated duct cells and the apical surface of striated duct epithelial cells stained for alpha-N-acetylgalactosamine.

Differentiation of ependymal surface of lateral ventricles in fetus and newborn rabbits: observations by SEM.

Abstract: Summary The ultrastructural modifications that occur on the ependymal surface of the lateral ventricles of prenatal rabbit brains at 25, 27, 29 days of pregnancy, of term fetuses (30–31 days) and of 5, 10, 15 day old newborn rabbits, were studied by a SEM On the ependymal surface the cilia, usually associated in tufts and the microvilli, variable in size and number, that surround them, show a rate of development correlated to the age The results show the early differentiation of the surface features commensurated with early cerebrospinal fluid (CSF) functioning

Anatomy of the development of the digestive tract and shape of the external body during the embryonic period of the goat (Capra hircus)

Abstract: The purpose of this work has been to establish the pattern of prenatal growth and normal development of the digestive tract and annex glands during goat embryonic stages. 21 embryos with ages ranging from 14 to 34 days (1.69 to 5.90 cm CR) as determined by registering the mating time, were obtained by cesarean section. This material was histologically processed to obtain complete serial sections of the stomatodaeum, foregut, midgut, hindgut and cloaca. In this work, it is chronologically described the morphogenesis and histogenesis of the mouth, hypophysis, pharynx and its derivatives, stomach, intestine, liver, pancreas and cloaca. The results obtained establish chronological comparisons with the development of the lamb and gives information on the unitary origin of the gastric compartments in ruminants.

Modelos Matematicos Aplicados al Crecimiento Gástrico Ovino durante la Vida Intrauterina

Abstract: Summary Mathematical models describing the histomorphometric growth of ruminant stomach during prenatal life One hundred forty four ovine embryos and feti were used in an investigation to determine mathematical models describing the histomorphometric growth of tissues and compartments of the ruminant stomach. The results indicate that during prenatal life the diameter of the gastric chambers increase more slowly than the length. The tissue layers of the gastric walls, particularly the muscular tunic of all compartments demonstrated a uniform tendency toward more rapid development than the compartment walls proper.

Sur L'innervation de la Syrinx Chez le Canard (Anas platyrhinchos)

Abstract: The innervation of the Syrinx was studied in 15 female Peking Ducks of 10 to 12 months old by using L.M. and E.M. In this organ a nervous plexiform net is present located in the connective below the epithelium along the membrana tympaniformis medialis. This net-work is made of the nervous trunks which repeatedly anastomise among themselves and display during their course acapsulate ganglions. However, no specialized contact device were encountered at the periphery.

Histology and Histomorphometry of the Tibial Diaphyseal Growth in Two Turkey Strains during the First Six Weeks after Hatching

Abstract: Summary The comparative cortical growth of the tibio-tarsus was studied during the first six weeks after hatching in two turkey strains, a light and a heavy one. At one day post-hatching the cortical appeared to be constituted in both strains of an embryonary non-active fibrous bone tissue which had completely disappeared at one week. On and after one week the cortice was constituted of a fibrolamellar adult bone tissue elaborated on the periosteal part of the cortex. Its vascular pattern depended on the strain and on the thickness of the cortical faces. The histomorphometrical studies showed that the growth in thickness was earlier and faster in the heavy strain with a Total Diaphyseal Surface twice larger at 6 weeks but a Diaphyseal Cortical Ratio not significantly different since 3 weeks of age.