scholarly journals Oral Myxoma in a Steer

2018 ◽  
Vol 46 ◽  
pp. 4
Author(s):  
Maria Helena Barros Pinto ◽  
Guilherme Reis Blume ◽  
Jussara Teixeira Medeiros ◽  
Ubirajara Oliveira Bilego ◽  
Fabiano José Teixeira De Sant'Ana
Keyword(s):  
Drinking Water ◽  
Oral Cavity ◽  
Alcian Blue ◽  
Clinical Signs ◽  
Surgical Excision ◽  
Northeastern Brazil ◽  
Blue Staining ◽  
Malignant Neoplasms ◽  
Current Case ◽  
Myxoid Matrix

Background: Myxoma is a benign neoplasm of mesenchymal cells producing a myxomatous matrix rich in mucopolysaccharides. This tumor occasionally has been described in older dogs and cats, and rarely occurs in other species. In ruminants myxomas can be found in the rumen and omasum, but there are no reports of these neoplasms involving the oral cavity of cattle. Only one case of myxoma was diagnosed in a 40-year study of 606 neoplasms in cattle in South Africa. Similar retrospective studies done in cattle from southern and northeastern Brazil also detected a single case of cutaneous myxoma. The current study reports the clinical and pathological findings of a rare occurrence of bovine oral myxoma.Case: A 22-month-old male crossbreed steer (Bosindicus) from the municipality of Rio Verde, GO (17°44′42″S 50°55′00″W), Brazil, presented a history of sialorrhea. There is no another affected animal in the herd. Clinical evaluation revealed mild swelling in the lower incisive gum. Treatment with flumetasone IM for three consecutive days was performed. Two months after this procedure, there was a considerable increase in the size to a flat, firm mass of 16x13x9 cm. Other clinical signs included emaciation and severe difficulty in feeding and drinking water. After surgical excision, fragments of the tumor were collected for histopathology. There is no local recurrence within approximately one year of the surgery. Microscopically, the lamina propria was found to be expanded and replaced by a nonencapsulated, moderately cellular, poorly demarcated, neoplastic proliferation. The lesion was composed of numerous loosely arranged bundles of cells in an abundant myxoid matrix. The bulk of the tumor parenchyma was formed by spindle or stellate cells with poorly demarcated borders and scant, eosinophilic cytoplasm. The nuclei were oval and hyperchromatic. Mild anisocytosis and anisokaryosis were present, along with rare mitotic figures. The myxoid matrix presented strong positive labeling to mucin by the Alcian blue staining. Based on the anatomopathological and histochemical findings, a diagnosis of myxoma was established.Discussion: Neoplasms of connective tissue originate from poorly differentiated fibroblasts and can produce collagenous (fibroma/fibrosarcoma) or mucinous (myxoma/myxosarcoma) stroma. In some cases, it is difficult to establish a histopathological classification and to distinguish between benign and malignant neoplasms, for which assessment of cell morphology, mitotic index, and biologic behavior are required. Very few cases of myxoma have been previously reported in cattle, this neoplasm and it was never diagnosed in the oral cavity of this species. Thre majority of neoplasms diagnosed in the oral cavity of cattle are squamous cell carcinomas and papillomas, although sporadic cases of lingual fibroma, lingual mastocytoma, odontoma and ameloblastic fibroma have been described. In the current case, the steer presented weight loss and difficulty in feeding and drinking water, probably due to the large volume of the neoplasm. Similar clinical signs can occur in cattle affected by other types of large neoplasms in the oral cavity. After surgical excision, the animal of the current report presented general improvement and considerable weight gain. The myxoma-related pathologic findings observed in the present case are similar to those described in other studies. Because myxoma is considered an infiltrative neoplasm, postoperative recurrence can occur; however, this was not noted in the current case and reports of myxoma in other species. The main differential diagnosis for myxoma is fibroma; the presence of mucin (Alcian blue positive) in the intercellular matrix as seen in the current case confirms the diagnosis of myxoma.

scholarly journals Maxillary odontogenic myxoma presenting mainly on nasal manifestation: a unique CT appearance of ‘floating’ tooth

2020 ◽  
Vol 7 (1) ◽  
pp. 163
Author(s):  
Najlaa Raihana Juhari ◽  
Chong Aun Wee
Keyword(s):  
Computed Tomography ◽  
Oral Cavity ◽  
Aggressive Behavior ◽  
Maxillary Sinus ◽  
Unusual Case ◽  
Surgical Excision ◽  
Lytic Lesion ◽  
Malignant Neoplasms ◽  
Odontogenic Myxoma ◽  
Radiographic Appearance

<p class="abstract">An odontogenic myxoma is a benign odontogenic tumor with locally aggressive behavior. It is relatively rare in the oral cavity. The diagnosis poses a challenge because its features overlap with those of other benign and malignant neoplasms. We present an unusual case of odontogenic myxoma with involvement of the maxilla extending to the maxillary sinus in a 17-year-old lady. A unique computed tomography (CT) appearance revealed a well circumscribed lytic lesion arising from the left maxilla causing expansion and thinning of the maxillary cortex. There is a discernible tooth with adjacent amorphous calcification in a round formation noted within the lesion. Biopsy revealed an odontogenic myxoma. The patient however did not undergo surgical excision as was not consented at the time of this write ups. This paper highlights the unique radiographic appearance of the pathology that has not been reported so far as well as to discuss its clinical significance.  </p>

scholarly journals Oral masses in African pygmy hedgehogs

2019 ◽  
Vol 31 (6) ◽  
pp. 864-867
Author(s):  
Gabriela Del Aguila ◽  
Cristian G. Torres ◽  
Francisco R. Carvallo ◽  
Carlos M. Gonzalez ◽  
Federico F. Cifuentes
Keyword(s):  
Oral Cavity ◽  
Clinical Signs ◽  
Surgical Excision ◽  
Gingival Hyperplasia ◽  
Mesenchymal Tumors ◽  
Caudal Portion ◽  
Neural Origin ◽  
Oral Neoplasms ◽  
The Right ◽  
Privately Owned

African pygmy hedgehogs ( Atelerix albiventris) frequently develop oral neoplasms, and most of these neoplasms are malignant. We characterized oral masses detected in hedgehogs at clinical examination. During a 1-y period, we diagnosed oral cavity masses in 27 privately owned hedgehogs; 16 were female and 11 were male, with ages of 2–7 y (mean: 4.3 y). Eight masses were non-neoplastic and were diagnosed as gingival hyperplasia (GH). Nineteen masses were neoplastic, of which 17 were squamous cell carcinomas (SCCs) and 2 were mesenchymal tumors (1 spindle cell tumor of probable neural origin, and 1 hemangiosarcoma). The GHs were noninvasive, exophytic, and did not recur after surgical excision. The SCCs were highly invasive tumors that induced facial deformation and were located in the caudal portion of the oral cavity, with 12 of them arising from the right-caudal maxilla. Thus, clinical signs, growth pattern, and anatomic location can be used to suspect a diagnosis of SCC among the other possible diagnoses, such as GH, in this location. However, histopathology is necessary for confirmation. Also, hemangiosarcoma should be considered among the differential diagnoses.

scholarly journals Mixossarcoma esplênico em cão

2017 ◽  
Vol 45 ◽  
pp. 4
Author(s):  
Taís Teixeira Zambarda ◽  
Mariana De Jesus De Souza ◽  
Jéssica Moreira Cannavon ◽  
Clarisse Felten ◽  
Saulo Petinatti Pavarini ◽  
...  
Keyword(s):  
Alcian Blue ◽  
Ultrasound Examination ◽  
Abdominal Cavity ◽  
Blue Staining ◽  
Alcian Blue Staining ◽  
Malignant Neoplasms ◽  
Histopathological Analysis ◽  
Small Animals ◽  
Immunohistochemical Examination ◽  
Neoplastic Cells

Background: Myxosarcomas (MXS) are malignant mesenchymal neoplasms originated from mainly mucin producing fibroblasts than collagen. Despite malignant neoplasms, MXS is believed to have low metastase generation ability. Myxosarcomas reports in dogs are widespread, usually involving trunk and limbs subcutaneous tissue. The aim of this report is to describe clinical, pathological, and immunohistochemistry aspects of a rare case of splenic myxosarcoma in a dog.Case: A 10-year-old, intact male Basset Hound, weiging 25 kg, showing signals such apathy, dark soft-stooled stools, progressive thinning, and increasing abdominal enlargement, perceived three months ago was brought to clinical consultation. Physical examination showed extremely pale oral and ocular mucosas, in addition to mild dehydration (6%), 35.4°C rectal temperature, and a very bulging abdomen, with no fluids or gases, evidence at abdominal percussion. A complete blood count (CBC) revealed neutrophilic leukocytosis and anemia. Patient´s abdominal cavity ultrasound examination showed an heterogeneous mass, occupying large part of cavity, and apparently from spleen origin. A spleenic multilobulated mass measuring 25 x 12 x 20 cm was obtained after exploratory laparotomy. The mass showed predominantly soft consistency with some firm areas, and no visible mesentery or other abdominal organs adhesions. Mass and spleen histopathological examination were routinely processed for histological analysis with haematoxylin and eosin and alcian blue staining. In addition, fragments of the neoplasm were submitted to immunohistochemistry (IHC) which confirmed myxosarcoma diagnosis. The owner returned to hospital two months after, complaining for apathy, prostration, anorexia, and abdominal pain. A new ultrasound examination were suggestive of liver and kidneys neoplasms. The tutor opted for patient´s euthanasia. However, dog´s necropsy was not authorized.Discussion: Myxosarcomas are malignant tumors considered rare in small animals, affecting mainly middle age or advanced age patients. Corroborating with the present case, the main clinical signs identified in cases of splenic neoplasias, in general, are abdominal distention and algia, emaciation, prostration, anemia, hypothermia, and inappetence. Regarding neutrophilic leukocytosis and anemia in CBC, those alterations are atributable to paraneoplastic syndromes commonly observed in small animals. The diagnosis of myxosarcoma was based on the pathological and IHC findings. The mesenchymal origin of the neoplastic cells was confirmed by the expression of vimentin and by the absence of cytokeratin labeling in the immunohistochemical examination. It was possible to confirm the diagnosis due to the presence of large amount of mucopolysaccharides between the neoplastic cells, demonstrated through Alcian Blue staining. Although rare, there have been reports of metastasis from cardiac myxosarcoma in humans and splenic myxosarcomas in dogs. The patient’s resubmission in two months with a new nonspecific clinical picture and documentation of hepatic and renal masses supports the possibility of agressive metastatic disease in the present case, despite the non-authorization of the autopsy examination. It was concluded by the present case report that MXS, although uncommon in small animals, should be included as a differential diagnosis in cases of abdominal neoplasias. The histopathological analysis and the immunohistochemical examination of neoplasms are important and should be considered in order to establish diagnosis and prognosis in dogs. Despite not confirmed by post-morten examination, agressive metastic disease seems likely in the present report, and emphasize MXS´malignat nature.

scholarly journals Equine coital exanthema caused by equid alphaherpesvirus 3: a report of an outbreak in northeastern Brazil

2021 ◽  
Vol 41 ◽  
Author(s):  
Givaldo B. Silva Filho ◽  
Hisadora A.S.C Bom ◽  
Silvio M.C. Fonseca ◽  
Érica A. Costa ◽  
Beatriz S.A.S. Santos ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Oral Cavity ◽  
Molecular Diagnosis ◽  
Clinical Signs ◽  
Rio Grande ◽  
The State ◽  
Northeastern Brazil ◽  
Semiarid Region ◽  
Blood Samples ◽  
Northeastern Region

ABSTRACT: Equine coital exanthema is a venereal infectious disease poorly reported in horses in Brazil and was never described in the northeastern region of the country. This work aims to describe the clinical and pathological aspects of an outbreak of equine coital exanthema caused by equid alphaherpesvirus 3, occurred in a herd of horses at the semiarid region of the State of Rio Grande do Norte. Main clinical signs consisted of anorexia, hiporexia, fibrinous or purulent secretion in the penis mucosa and vagina. Two mares presented mild to minimal lesions that consisted of scars in the mucosa of the vagina and in the perivulvar region. In a stallion the disease consisted of severe, multifocal, umbilicated-exanthematous ulcers of approximately 1cm in diameter on the penis mucosa. Other areas where ulcers and crusts were focally observed included the skin of the scrotum and on the lips and mucocutaneous junctions of the oral cavity. Histologically, the main lesion consisted of multifocal severe ulcerative and fibrinous necrotizing balanoposthitis and mild multifocal necrotizing, lymphocytic dermatitis in the lips and scrotum. The equide alphaherpesvirus 3 DNA was amplified in blood samples and penis mucosa using the PCR technique. This is the first report of molecular diagnosis of equine coital exanthema affecting horses in northeastern Brazil. Further studies should be carried out in order to investigate the epidemiology and the importance of this herpetic disease in the country.

scholarly journals Clinical and Complementary Diagnosis of Sinus Neoplasia in Horses

2021 ◽  
Vol 49 ◽  
Author(s):  
Tatiana Yumi Mizucina Akutagawa ◽  
Ricardo De Francisco Strefezzi ◽  
Carla Bargi Belli ◽  
Raquel Yvonne Arantes Baccarin ◽  
Luis Cláudio Lopes Correia Da Silva ◽  
...  
Keyword(s):  
Early Diagnosis ◽  
Oral Cavity ◽  
Clinical Signs ◽  
Surgical Excision ◽  
Anaplastic Carcinoma ◽  
Clinical Aspects ◽  
Ossifying Fibroma ◽  
Complementary Methods ◽  
Poorly Differentiated Carcinoma ◽  
Poorly Differentiated

Background: Sinus neoplasms are reported as low frequency in horses. Its clinical characteristics are often nonspecific, depend on complementary methods for diagnosis, and when diagnosed, generally they are already advanced, limiting therapeutic possibilities. The objective of this case series was to detail clinical aspects and complementary exams for sinus neoplasms for early diagnosis, comparing them with the literature.Cases: Four horses were treated at the College of Veterinary Medicine and Animal Science of the University of São Paulo, with different clinical signs and previous diagnoses, which when evaluated by respiratory endoscopy, radiography, oral cavity evaluation and histopathological exams, revealed the diagnosis of anaplastic carcinoma, poorly differentiated carcinoma, ossifying fibroma and lymphoma. Previous diagnosis, based mainly on clinical signs, were sinusitis secondary to apical infection, ethmoidal hematoma, sinus cyst and sinusitis secondary to periapical disease. The cases of anaplastic carcinoma (case 1) and lymphoma (case 4) presented with an advanced degree of the disease with involvement and destruction of paranasal structures and adjacent tissues, in addition to a poor general condition, which made surgical treatment impossible and led to euthanasia. In these cases, previous treatment was made to apical infection and periodontal disease with secondary sinusitis, but negative evolution led to suspicion of neoplasia, confirmed by histopathological exam of incisional biopsy of the mass in oral cavity. Benign ossifying fibroma (case 3) presented with progressive respiratory difficulty due to occlusion of the lumen of some nasal meatus and radiographic signs of invasion and deformation of the adjacent bones, it was submitted for surgical excision and there was no recurrence until hospital discharge. The poorly differentiated carcinoma (case 2) was a multilobulate neoformation in the ethmoidal region, similar to ethmoid hematoma in endoscopic and radiographic evaluation, it was submitted for excision and two sessions of electrochemotherapy with bleomycin, associated with administration of piroxicam, which obtained a good result until the period of 1 year after discharge.Discussion: It was found that many characteristics are common with these types of neoplasms, and the clinical signs, such as nasal secretions, airway obstruction, increased facial volume, severe alterations in oral cavity, although unspecific, suggest the differential diagnosis for neoplasms. It is important to differentiate from other diseases noting the evolution and growth of these tumors, like in cases 1 and 4, especially the growth to internal tissues, using complementary methods described here, like endoscopic and radiographic examination. Late identification or even manipulation of neoplasms, without proper diagnosis, leads to a few prognoses regarding life. When it is possible to perform surgical excision, complementary methods are important to guide the procedure, and definitive diagnosis is made through histopathologic exam and some need immunohistochemistry analysis. Cases 2 and 3 had surgical access, were submitted to excision and treatment with good results, both with close monitoring in first months and prolonged quality of life. These results highlight the importance of complementary methods for early diagnosis, correct intervention and monitoring of evolution.Keywords: sinus neoplasia, paranasal sinus, tumor, head, horses.

scholarly journals Renal Myxoma in a Feline

2019 ◽  
Vol 47 ◽  
Author(s):  
Thayná Oliveira Da Silva ◽  
Fernanda Zuliani ◽  
Noeme Sousa Rocha ◽  
Carlos Eduardo Fonseca Alves
Keyword(s):  
Veterinary Medicine ◽  
Incidence Rate ◽  
Alcian Blue ◽  
Renal Tumors ◽  
Blue Staining ◽  
Benign Tumors ◽  
Renal Neoplasms ◽  
Feline Infectious Peritonitis ◽  
Presenting Symptoms ◽  
Myxoid Matrix

Background: Renal neoplasms are a rare condition in felines, with metastatic lymphoma presenting the highest incidence rate. Secondary renal neoplasms are more frequent (88%) than primary renal tumors, with primary mesenquimal renal neoplasms accounting for 22% of the cases and the incidence of benign tumors not exceeding 5%. Myxomas are neoplasms in undifferentiated mesenchymal cells with abundant reproduction of the myxoid matrix, with few few case reports about this type of neoplasm in the veterinary literature. This study reports the first case of renal myxoma in a young feline afflicted by granulomatous nephritis and diagnosed with FIP (Feline Infectious Peritonitis).Case: A 9-month-old, male, mixed breed feline, was admitted into the Veterinary Hospital maintained by the School of Veterinary Medicine and Animal Science, Botucatu, Brazil, presenting symptoms such progressive weight loss and occasional episodes of emesis for one week, progressing to anorexia, hematochezia, vocalization, lack of coordination, spasms, anuria and inability to defecate. A physical examination revealed moderate dehydration, low temperatures (< 33ºC), dyspnea (36 mpm), slight hyperglycemia (187 mg/dL) and distension of the abdomen and of the urinary bladder. The hematological assay and the serum biochemistry assay revealed neutrophilic leukocytosis, thrombocytopenia, anemia and slight uremia. In view of the severity of the neurologic signs and lack of response to the clinical treatment, the owner opted to euthanize the animal. The necropsy revealed diffused jaundice, with kidney injuries observed through the pale coloration of the tissue and irregular surface with multiple off-white small nodules distributed in a marked and diffuse way. The same injury pattern was observed markedly in the lungs and discretely in the spleen and liver. The material collected was fixed in a 10% formalin solution, and processed according to the routine technique (Hematoxylin & Eosin). The remaining samples were submitted to a histochemical analysis with the Alcian Blue and Masson’s Trichrome stains, in addition to an immunohistochemical expression test. The histopathological examination with H&E staining revealed multiple focuses of pyogranulomatous injuries in the kidneys, lungs, spleen, uvea and leptomeninges, corroborating the diagnosis of feline infectious peritonitis (FIP). In addition, there was a neoplastic proliferation of fusiform cells among an abundant myxoid matrix, evident in Alcian Blue staining. Normal renal tissue, such as glomeruli or tubules, were occasionally observed inside the neoplastic proliferation. Masson’s Trichrome technique was used to exclude the possibility of a fibroblastic origin. In addition, immunohistochemistry (IHC) was performed to confirm the diagnosis of myxoma using the Vimentin, pan-cytokeratin and p63 antibodies. Discussion: Kidney tumors are rare in veterinary medicine, but have an incidence rate four to five times greater in cats than in dogs. The veterinary literature describes myxomas located in joints, cardiac valves and ureter, but reports of myxomas afflicting the kidneys are more commons in human medicine. This tumor should be included in the differential diagnosis process for young cats with suspicions of renal neoplasms, however, to differentiate between neoplasms with a myxoid component in benign tumors. This is the first reported case of renal myxoma afflicting a young feline with feline infectious peritonitis (FIP) in the veterinary literature.

scholarly journals LARYNGOTRACHEITIS VIRUS IN CHICKENS

1967 ◽  
Vol 125 (3) ◽  
pp. 409-428 ◽  
Author(s):  
Betsy G. Bang ◽  
Frederik B. Bang
Keyword(s):  
Alcian Blue ◽  
Plasma Cells ◽  
Giant Cells ◽  
Functional Restoration ◽  
Nasal Fossa ◽  
Blue Staining ◽  
Alcian Blue Staining ◽  
Cell Nuclei ◽  
Histochemical Change ◽  
Laryngotracheitis Virus

Infectious laryngotracheitis can be produced in chickens as an experimental model of severe nonfatal rhinitis and sinusitis. Inoculated intranasally into unanesthetized baby chicks it remains limited to the nasal fossa, produces acute desquamation of all nasal epithelia, results in functional recovery of the respiratory epithelium, but leaves important residual abnormalities. From the earliest recognizable lesions through 4½ months' convalescence, the principal changes are as follows: 1. Initial lesions, or small syncytia of intranuclear "inclusions", first identifiable in the mucociliated cells of the shallowest portion of the epithelium at about 21 hr postinoculum (the inner surface of the maxillary conchal scroll). 2. Acute sloughing, (about 3 to 7 days), marked by: (a) spread of lesions from cell to cell via multinucleated "giant cells" which progressively slough and desquamate respiratory, olfactory, and sinus epithelia, epithelial neural elements and blood vessels; (b) appearance of numbers of eosinophilic leukocytes along the basement membrane at the sites of lesions just previous to sloughing; intensive infiltration of the submucosa with small lymphocytes after sloughing begins; (c) histochemical change in the intracellular mucus of the cells which comprise the syncytia: this mucus stains with Alcian blue alone when stained with AB-PAS; and (d) all cartilages of the maxillary conchae become flaccid, and the cell nuclei and matrix lose both basophilic and Alcian blue staining properties, effects which recede by about the 8th day. 3. Repair (about 8 to 21 days), marked by rapid initial spread of a sheet of epithelial cells over the infiltrated subrmucosa, appearance of numbers of plasma cells circulating in the tissues, formation of encapsulated secondary nodules, and mucosal adhesions. 4. Convalescence (about 1 to 4½ months when experiments terminated), marked by functional restoration of the mucociliary lining of the nasal fossa. However, at 4½ months eight specimens all show complete metaplasia of the olfactory organ (end nerves, supporting cells, and glands of Bowman) to mucociliated epithelium, all show abnormal formation and alignment of mucous acini, and about 50% have severe persistent sinusitis.

Histochemical observations on the tegumentary epithelium and interproglottidal glands of Moniezia expansa (Rud., 1805) (Cestoda, Cyclophyllidea)

Parasitology ◽  
1969 ◽  
Vol 59 (3) ◽  
pp. 505-518 ◽  
Author(s):  
R. E. Howells ◽  
D. A. Erasmus
Keyword(s):  
Alcian Blue ◽  
Regional Differences ◽  
Succinic Dehydrogenase ◽  
Neck Region ◽  
Secretory Activity ◽  
Blue Staining ◽  
Alcian Blue Staining ◽  
Light Microscope Level ◽  
Gland Cells ◽  
Moniezia Expansa

Regional differences in the tegumentary tissue of Moniezia expansa, as revealed at the light-microscope level by histological and histochemical techniques, are described and evidence for secretory activity by the interproglottidal glands is presented.In very immature proglottides the interproglottidal glands are at the ‘precryptic’ stage. Gland cells may be differentiated from other tegumentary cells by their high RNA content and in certain gland cells the presence of an alcian blue staining material.In mature proglottides the glands consist of rosette-like clusters of cells around crypt-like intuckings of the tegument. Two types of cells are found in the gland, small alcian blue-staining cells which are most numerous in the neck region of the crypt, and larger cells, the predominant gland cells, which do not stain with alcian blue but possess non-specific esterase activity. No other tegumentary cells in Moniezia exhibit this activity. Esterase and phosphatase activity is found in the tegument and crypt of the glands and in the interproglottidal folds.The non-enzyme histochemistry confirms and extends the observations of previous workers.Cytochrome oxidase and succinic dehydrogenase were detected in the tegumentary cells and tegument. Very strong reactions were given in the neck and scolex, with a progressive diminution of activity posteriorly along the strobila. Very low activities were recorded in the tegument of the glands.

Oral (Drinking Water) Two-Generation Reproductive Toxicity Study of Bromodichloromethane (BDCM) in Rats

2002 ◽  
Vol 21 (2) ◽  
pp. 115-146 ◽  
Author(s):  
M. S. Christian ◽  
R. G. York ◽  
A. M. Hoberman ◽  
L. C. Fisher ◽  
W. Ray Brown
Keyword(s):  
Drinking Water ◽  
Reproductive Toxicity ◽  
Clinical Signs ◽  
Sperm Parameters ◽  
Feed Consumption ◽  
Exposure Level ◽  
Organ Weights ◽  
Reduced Body ◽  
Body Weights ◽  
Adult Exposure

Bromodichloromethane (BDCM) was tested for reproductive toxicity in a two-generation study in CRL SD rats. Thirty rats/sex/group/generation were continuously provided BDCM in drinking water at 0 (control carrier, reverse osmosis membrane-processed water), 50, 150, and 450 ppm (0,4.1 to 12.6, 11.6 to 40.2, and 29.5 to 109.0 mg/kg/day, respectively). Adult human intake approximates 0.8 μg/kg/day (0.0008 mg/kg/day). P and F1 rats were observed for general toxicity (viability, clinical signs, water and feed consumption, body weights, organ weights [also three weanling F1 and F2 pups/sex/litter], histopathology [10/sex, 0-and 450-ppm exposure groups]) and reproduction (mating, fertility, abortions, premature deliveries, durations of gestation, litter sizes, sex ratios, viabilities, maternal behaviors, reproductive organ weights [also three weanling F1 and F2 pups/sex/litter], sperm parameters, and implantations. F1 rats were evaluated for age at vaginal patency or preputial separation. Ten P and F1 rats/sex from the 0-and 450-ppm exposure groups and rats at 50 and 150 ppm with reduced fertility were evaluated for histopathology (gross lesions, testes, intact epididymis, all F1 dams for number of primordial follicles). Developmental parameters in offspring included implantation and pup numbers, sexes, viabilities, body weights, gross external alterations, and reproductive parameters (F1 adults). Toxicologically important, statistically significant effects at 150 and/or 450 ppm included mortality and clinical signs associated with reduced absolute and relative water consumption, reduced body weights and weight gains, and reduced absolute and relative feed consumption (P and F1 rats). Significantly reduced body weights at 150 and 450 ppm were associated with reduced organ weights and increased organ weight ratios (% body and/or brain weight). Histopathology did not identify abnormalities. Small delays in sexual maturation (preputial separation, vaginal patency) and more F1 rats with prolonged diestrus were also attributable to severely reduced pup body weights. Mating, fertility, sperm parameters, and primordial ovarian follicular counts were unaffected. The no-observable-adverse-effect level (NOAEL) and the reproductive and developmental NOAELs for BDCM were at least 50 ppm (4.1 to 12.6 mg/kg/day), 5125 to 15,750 times the human adult exposure level, if delayed sexual maturational associated with severely reduced body weights is considered reproductive toxicity. If considered general toxicity, reproductive and developmental NOAELs for BDCM are greater than 450 ppm (29.5 to 109.0 mg/kg/day), or 36,875 to 136,250 times the human adult exposure level. Regardless, these data indicate that BDCM should not be identified as a risk to human reproductive performance or development of human conceptuses.

Determination of the L-ascorbic acid requirements in Wistar osteogenic disorder Shionogi rats for prolonged carcinogenesis experiments

1996 ◽  
Vol 30 (4) ◽  
pp. 337-346 ◽  
Author(s):  
S. W. Y. Chan ◽  
P. C. Reade
Keyword(s):  
Animal Model ◽  
Ascorbic Acid ◽  
Drinking Water ◽  
Normal Level ◽  
Physical Condition ◽  
Wistar Rats ◽  
Clinical Signs ◽  
Supplement Group ◽  
Palatal Mucosa

Wistar Shionogi rats of the ( od/od) substrain with the osteogenic disorder are unable to synthesize L-ascorbic acid ( L-AA) and appear to be an appropriate animal model for studying the effect of L-AA in carcinogenesis. To determine the minimal L-AA requirements of these animals for prolonged survival in a satisfactory physical condition during experimentation, four concentrations of L-AA (0.33 g/l, 0.67 g/l, 1.67 g/l and 3.33 g/l) were administered via drinking water to four groups of animals ( n=2). Their water intake per cage was recorded three times weekly and the plasma L-AA levels were determined at the start, after 2, 4, 8 and 12 weeks and at the termination of the experiment. To simulate the procedures to be undertaken in oral mucosal carcinogenesis experiments, the animals were gently restrained and a designated amount of sterile NaCl was applied to the palatal mucosa three times a week for 26 weeks. The L-AA supplement group with the lowest concentration (0.33 g/l L-AA) achieved mean plasma levels of 7 ± 1.38 μM, approximately one-eighth that of the normal level (mean plasma L-AA level in outbred Wistar rats was found to be 58 ± 3 μM) whilst those in the higher supplement group (3.33 g/l L-AA) achieved a mean of 18 ± 1.25 μM. All of the animals employed in the present study survived for 26 weeks and showed no clinical signs of L-AA deficiency during this period.

Sign in / Sign up

Export Citation Format

Share Document