Blood flows in tributaries of the portal vein: anatomical and angiographic studies in normal beagle dogs.

Liver anatomy, particularly its vascularization, has been investigated in many studies in dogs. Knowledge of blood flow from the main tributaries of the portal vein (PV) is necessary to explain the preferential sites of secondary lesions within the liver based on the site of the initial malignant lesion. How these flows come together was established in an earlier ex vivo study. Here, we highlight in vivo the blood flows from the main PV tributaries and their distribution in the liver of normal dogs. Portographs of the main PV tributaries were obtained in seven dogs after injection of an angiographic contrast medium. After euthanasia, the livers and their portal vascularization (PV and tributaries) were extracted for a comparative corrosion cast study. Flows were demonstrated in the cranial mesenteric vein, caudal mesenteric vein and splenic vein. However, no proper flow could be distinguished for the gastroduodenal and ileocolic veins. All these tributaries primarily supply the lateral liver lobes (right or left). Most of our observations indicate that the cranial mesenteric, caudal mesenteric and splenic veins primarily supply the right lateral lobe and the caudate process of the caudate lobe and secondarily the left lateral lobe, left medial lobe and the quadrate lobe. The two other tributaries (gastroduodenal and ileocolic veins) primarily supply the right lateral lobe and the caudate process of the caudate lobe.

Normal canine prostate gland: repeatability, reproducibility, observer-dependent variability of ultrasonographic measurements of the prostate in healthy intact beagles.

Most prostatic diseases in dogs are associated with prostatomegaly, and transabdominal ultrasonography has become the imaging modality of choice for evaluation of the prostate gland in the dog. The aim of the present study was to assess the reproducibility, the repeatability and interobserver variations of sonographic measurements of prostate and to determine which measurement had the lowest variability. Length and height of prostate gland were measured on longitudinal views, width of the prostate gland and height of left and right lobes of the gland on transversal views. The within-day and between-day variabilities of the prostatic parameters were determined by performing 1350 (270 length, 270 height, 270 width, 270 height of right lobe and 270 height of left lobe) examinations on ten healthy intact beagle dogs on six different days, in a two-week period (three days for the five dogs, three different days for the five others). Three observers with different levels of experience in ultrasonography performed the examinations. The lowest within-day and between-day standard deviation and coefficient of variation values were observed for the width of the prostate. The width of the gland measured on transverse frozen images seems to be the most reliable measurement for evaluating size of prostate glands in healthy dogs, although the shape, position, outline, and echogenicity of the prostate should also be assessed.

Normal feline brain: clinical anatomy using magnetic resonance imaging.

The purpose of this study was to provide a clinical anatomy atlas of the feline brain using magnetic resonance imaging (MRI). Brains of twelve normal cats were imaged using a 1.5 T magnetic resonance unit and an inversion/recovery sequence (T1). Fourteen relevant MRI sections were chosen in transverse, dorsal, median and sagittal planes. Anatomic structures were identified and labelled using anatomical texts and Nomina Anatomica Veterinaria, sectioned specimen heads, and previously published articles. The MRI sections were stained according to the major embryological and anatomical subdivisions of the brain. The relevant anatomical structures seen on MRI will assist clinicians to better understand MR images and to relate this neuro-anatomy to clinical signs.

Magnetic resonance imaging of normal nasal cavity and paranasal sinuses in cats.

A detailed description of the nasal cavity and paranasal sinuses in clinically normal cats using magnetic resonance imaging (MRI) is presented. The heads of seven normal cats were imaged using a 1.5-T MR unit and two sequences spin echo (SE) T1-weighted and fast spin echo (FSE) T2-weighted. Eighteen relevant MR scans were taken in the transverse (12 scans) and dorsal (six scans) planes. Anatomical structures were identified and labelled using anatomical texts, sectioned specimen heads and previous studies. MR scans revealed the soft-tissue structure of the head. Identified relevant anatomical structures seen on MRI will assist clinicians to better understand MR images and evaluate pathological conditions that affect the nasal region.

Ultrasonographic evaluation of the adrenal glands in healthy dogs: repeatability, reproducibility, observer-dependent variability, and the effect of bodyweight, age and sex.

Adrenal length and width were determined from two-dimensional ultrasound longitudinal images. In study 1, 540 measurements of adrenal glands were attempted from five healthy beagle dogs by three different observers with different levels of expertise in ultrasonography, to determine the variability of adrenal gland measurements. Of these, 484 measurements were included in the statistical analysis, since 16 measurements of the left adrenal gland and 40 for the right could not be visualised by the observer. In study 2, a single measurement of both adrenal glands was taken from each of 146 dogs by the most trained observer from study 1, and the effects of different health status (healthy dogs v dogs with non-adrenal diseases), bodyweight, age and sex were assessed. A total of 267 measurements were included in the statistical analysis. The lowest intra- and inter-day coefficient of variation values were observed for the left adrenal gland and by the most trained observer. The health status had no statistically significant effect on adrenal gland length or width, whereas age had a significant effect only for the left adrenal gland (the greater the age, the greater the width or length) and sex had a significant effect only for the right adrenal gland (the width was larger in males and the length larger in females). The bodyweight had a significant effect for the length of both adrenal glands (the greater the bodyweight, the greater the length), but not the width. The differences between sd and coefficient of variation values for the width of the left adrenal gland were not statistically significant between the three observers, whereas they were statistically significant for the right adrenal gland.

The topography of the lymph vessels of mammary glands in female cats.

Malignant tumours of the mammary gland in the female cat metastasize, especially through the lymphatic system. However, the anatomical knowledge of this system in cats is not sufficient to develop a reasoned model for the extirpation of these glands in the case of malignant tumours. A study of the topography of the collector vessels in 50 female cats was conducted by indirect injection in vivo of India ink inside the mammary parenchyma. All the lymph nodes were controlled by microscopic examination and lymph vessels were examined after clearing. The success rate of the colouration of the lymph vessels was 76.4%. Clearing showed several principal routes of drainage, different for each gland. Contrary to the presentation observed in the bitch, no evidence existed in any of the 65 cases of lymphatic plexuses connecting the two mammary glands of each row in the female cat. The result of this study is in favour of the development of a new model for the surgical extirpation of mammary tumours in cats.

Lymph drainage of the mammary glands in female cats.

The mammary gland is a common site of neoplasms in the female cat. All the malignant tumors metastasize to a lesser or a greater extent through the lymphatic system. However, the anatomical knowledge of this system is not sufficiently well known in cats to develop a reasoned model for the extirpation of these glands in case of malignant tumors. A study of the lymph drainage in 50 female cats was done by indirect injection in vivo of India ink inside the mammary parenchyma. After a waiting interval, mammary glands were extracted and the thoracic cavity opened. All the lymph nodes were examined after clearing. The success rate of the colorations of lymph nodes and lymph vessels was 91.8%. Out of the 100 observed mammary chains, the two intermediate mammary glands (T2, A1) may drain caudally to the superficial inguinal lymph center and/or cranially to the axillary lymph center. The T1 gland always drains exclusively cranially and A2 exclusively caudally. The two mammary glands (T1 and A1) often drain towards the sternal cranial lymph nodes, but 100% of the T2 drain towards it. This research assumes that the limit between the two directions of drainage can exist only between glands T2 and A1. The results obtained with the study of the 1st, 2nd, 3rd, and 4th mammary glands permit production of new and more complete data of functional significance that will eventually aid block dissection surgical technique in the removal of malignant tumors in cats.

Mophometric study of the aortic arch and its major branches in rat fetuses on the 21st day of gestation.

The anatomy and embryology of the aortic arch and its branching tributaries (brachiocephalic trunk, left common carotid artery and left subclavian artery) in man and animals are well substantiated. However, the anatomical variations and morphometry of the aortic arch and its branching tributaries in rat fetus at the 21st gestation day have not been studied. Pregnant rats were hysterectomized and the arterial systems of 114 fetuses were injected with a polymerisable resin through the umbilical artery. After maceration, the vascular casts were dissected out and prepared for observations under a scanning electron microscope (SEM). The resulting SEM pictures were studied with a picture analyser and different vessel parameters (diameters, lengths and angles) were measured. The success rate of the microvascular cast injection was 46.5%. Out of the 53 observed aortic arch casts, 98.1% showed the classical branching pattern and one (1.9%) had no brachiocephalic trunk. Morphological analysis showed many differences, which were not linked to the litter. The statistical processing of the measurements enabled us to determine that the aorta diameter after the branching of the left subclavian artery was the most replicable parameter. Moreover, the results revealed some strong correlations between different parameters. There are probably no discrete categories among the various observed parameters as diameters and angles. Some parameters show very little variability and can thus be used as reference points for further studies such as the comparison of a control population with a population treated with a relevant xenobiotic.

An immunohistochemical study of bovine palatine and pharyngeal tonsils at 21, 60 and 300 days of age.

An immunohistochemical study was performed on three groups of young cattle (21, 60 and 300 days of age). Tonsils (palatine and pharyngeal) and mucosae (nasal and oral) were removed. Eight monoclonal antibodies (specific for CD3, CD2, CD4, CD8, WC1, cell-surface IgM, cell-surface IgG and MHC class II molecules) and an avidin/biotin complex method on frozen sections were used. The immunological cytoarchitecture of bovine tonsils is similar to that of human tonsils. Nevertheless, these lymphoid tissues are not fully developed during the first weeks of life: T and B dependent areas not well-differentiated, few germinal centres, few intra-epithelial WC1+ T lymphocytes. In contrast, at 2 months, tonsils possess all the elements of a mucosa-associated lymphoid tissue (MALT). Tonsillar or mucosal epithelium is infiltrated by a large number of CD8+, WC1+ T lymphocytes and cells which express MHC class II molecules. Between 21 and 60 days, the number of WC1+ T lymphocytes increase markedly in the tonsillar epithelium. These results accredit the hypothesis that the presence of antigens has an effect on the localization of these lymphocytes at these sites.

Injection technique and scanning electron microscopic study of the arterial pattern of the 20 gestation days (G20) rat fetus.

A technique to obtain microvascular corrosion casts of the G20 rat fetus and the normal pattern of the main arteries of the G20 rat fetus are described. The casts were studied by means of scanning electron microscopy (SEM). The arterial pattern is similar to that described in the adult; however, several variations have been found. It is concluded that the use of vascular corrosion casts studied by SEM may be particularly helpful to observe the extremely small arteries of rat fetuses. Moreover, we suggest that this technique may be useful in practical teratological studies.

Study of the distribution of albendazole-sulphoxide (ABZ-SO) in fertilized egg compartments.

In order to use the chicken embryo in teratogenic studies, it is necessary to know the internal volume in which a xenobiotic distributes. The inoculation of a xenobiotic in one of the compartments of the fertilized egg is the usual technique used in these studies. Neither the concentration nor the moment in which the xenobiotic comes into contact with the chicken embryo have been considered. Predicting the internal volume of distribution in the egg from some of the external parameters that do not interfere with the normal development is necessary. A simple method to calibrate these external parameters and their correlation with the different compartments of the fertilized eggs as well as the different distribution of the xenobiotic in these compartments has been successfully demonstrated. After injection of ABZ-SO, the maximum concentration in the embryo is reached by 36 h. The mean AUC for the albumen (sharp and obtuse end), yolk, and embryo were 78.4, 40.7, 79.2, and 10.8 micrograms.h/ml respectively. The results obtained about the kinetics of the diffusion of ABZ-SO indicate that this compound does not have a homogeneous distribution in all the compartments of the fertilized egg. These results highlight that whenever fertilized eggs are used as a screening for the possible toxicity of a drug or other substances, the dose of the xenobiotic to be injected has to be precisely determined in accordance with the total volume and the stage of embryonic development selected to be affected, starting from the previous knowledge of when and how much substance accedes to the embryo.

The morphometric study of the 19-day chicken embryo skeleton (gallus domesticus).

A series of 40 chicken embryos were processed after 19 d of incubation by dissection, diaphanisation, skeleton stained with alizarin red and examined by image analysis. Six bones (femur, tibiotarsus, tarsometatarsus, humerus, ulna and carpometacarpus) and 4 parameters (perimeter, area, the largest and the smallest Feret diameter) were evaluated. The smallest Feret diameter proved unusable. The coefficients of variation for the other 3 parameters were comparable for the 6 bones. All the bones were valuable for comparing morphometric values between a control population and a population treated with a xenobiotic in order to quantify the chemical's influence on ossification.

Transplacental transport of netobimin metabolites in ewes.

Neither netobimin (NTB) nor its metabolite albendazole (ABZ) were found in plasma after an oral administration of 20 mg/kg of NTB to pregnant ewes during the last third of gestation. ABZ metabolites, albendazole sulphoxide (ABZSO) and albendazole sulphone (ABZSO2) were found in plasma 30 min and 2 h, respectively, after administration. The maximal plasma concentration (Cmax) of ABZSO was detected at 11.6 +/- 1.0 h and for ABZSO2 at 16.5 +/- 2.3 h. The plasma levels of the latter remained constant for 36 h, and decreased as ABZSO was removed from the blood. Jugular plasma levels of both metabolites did not differ significantly from those observed in the ovarian vein, suggesting that there were no exchanges between foetal and placental tissues. Both metabolite concentrations were similar in the umbilical vein and artery and in the amniotic and allantoic fluids, their values were half the maternal plasma concentration, leading to the conclusion that there was transplacental movement of metabolites. Both metabolites reached the foetus and could be responsible for the teratogenicity of NTB in sheep.

Histochemical and morphometric study of the cricoarytenoideus lateralis muscle in the horse.

Histochemical and morphometric parameters of the cricoarytenoideus lateralis muscle of the horse are presented. Using myosin ATPase staining after acid preincubation, 3 fibre types (I, IIA and IIC) were identified. Using NADH-TR staining, type I fibres showed high oxidative capacity, whereas type II fibres had high or low oxidative capacity. The type I to type II ratio was of 35:65. This ratio remained constant in the age range examined. Statistically significant (p < 0.01) differences were found in values for fibre size between groups of horses weighing more than 500 kg and less than 400 kg. Mean area of type II fibres was greater (p < 0.001) than that of type I fibres. There were no significant differences in mean area between left and right muscles in the group of animals with less weight. In contrast, significant differences (p < 0.05) in mean area between left and right muscles were found for type I fibres in the group of animals exhibiting a higher weight. The histographical distribution of fibre type areas was unimodal. Most adult horses showed muscle fibre type grouping in the left muscle.

Muscular pathology in equine laryngeal neuropathy.

Three adductor muscles of the larynx, the cricoarytenoideus lateralis (CAL), the arytenoideus transversus (AT) and the ventricularis (Ve), from 36 horses were examined histologically. The neurogenic changes seen in each muscle were evaluated qualitatively. In addition, in 6 horses with clinical and subclinical signs of neurogenic atrophy, measurements of muscle fibre area were performed. Neurogenic changes observed in the Ve were less than in CAL and AT. Measurements of muscle fibre area also demonstrated that CAL and AT showed a wider range of pathological changes than did Ve. The results show that denervation does not uniformly affect all adductor muscles of the larynx. On the other hand, the appearance in some animals of fibre type grouping in the right AT to the same or to a greater extent than in the left AT supports the classification of equine laryngeal neuropathy as a distal axonopathy.

Morphometric study of the recurrent laryngeal nerve in young 'normal' horses.

Quantitative measurements were made on cross-sectional preparations of the distal part of the recurrent laryngeal nerve (RLN) from nine young mixed-breed horses to establish reference values for the total number of myelinated fibres, mean fibre diameter and percentage of thickest fibres (over 9.5 microns) and to delineate diameter distribution curves. The total number of myelinated fibres, mean fibre diameter and percentage of thickest fibres for the left RLN were significantly lower than those of the right RLN (P < 0.005). The distribution of fibres was unimodal. The fibre diameter ranged from 1 micron to 17 microns. Approximately, 95 per cent of fibres had a diameter larger than 5 microns.

[Lymphaticovenous communication in the mammary gland of the female dog]. / Communications lymphatico-veineuses dans la glande mammaire de la chienne.

Lymphaticovenous Communications were searched in the mammary glands of 24 bitches. Injections of indian ink into the interstice of living animals were followed after death by the filling of the veins with latex and barium sulphate. Afterwards, the used techniques were: microdissection, angiography, clarification and histological section. The results obtained would seem to prove the existence of Lymphovenous Anastomoses. The roles of these communications in the canine mammary gland neoplasia are discussed.

[Topography of the lymphatic collecting ducts of the mammary glands of the dog]. / Topographie des collecteurs lymphatiques mammaires de la chienne.

The topography of the lymph drainage was examined by in vivo injections of india ink into the mammary parenchyma of 73 female dogs. Only one gland was injected at a time on each side. Only the cranial abdominal mammary gland had direct drainage to the axillary as well as to the superficial inguinal nodes. The principal routes of drainage differ for each gland. The glands on each side are completely independent as regards their lymph drainage. The cranial thoracic mammary glands on each side had their own collecting duct which led to the sternal lymph nodes. The results of this study suggest to develop a new model for the surgical extirpation of mammary tumors in the bitch.

The urethral muscle (musculus urethralis) of the female calf. Anatomical, histological, histochemical and morphometrical data.

Parts of the female urethra were examined topographically and microscopically in the female calf. The thickness and the straight course of the fibres of the musculus urethralis could best be analyzed in the ventromedian region of the urethra. Examination of the surface area and the distribution of the two primary metabolic fibre types showed that the urethral muscle is capable of contracting quickly with predominantly anaerobic metabolism. The different relationships between type I and type II fibres could be determined also in relation to the position of the lamina propria mucosae.