A case of suspected lysosomal storage disease in a neonatal Japanese black calf

A 5-day-old Japanese black calf was necropsied and intracytoplasmic vacuolations were histologically observed in many tissues. In the central nervous system, intracytoplasmic inclusions and vacuoles were found in neuronal cells. Intracytoplasmic inclusions were more conspicuous in the nuclei containing large nerve cells, especially in the brain stem and spinal cord. These inclusions were stained weak positive to positive with alcian blue, Giemsa, Luxol fast blue and periodic acid-Schiff stains but not with oil red O. Ultrastructurally, neuronal inclusions were observed in lysosomes and consisted of an amorphous electron-dense substance and occasional membranous structures. These findings seem to differ from the cases of bovine lysosomal diseases that have been reported, and this case may be another type of lysosomal storage disease.     

Primary erythrocytosis in a Japanese black calf: a case report

An 8-month-old Japanese Black heifer with severe erythropoietic symptoms was subjected to clinical, histological and cytological examinations. During the 1 month clinical observation period, severe increases in RBC count, packed cell volume and haemoglobin concentration were observed. The plasma erythropoietin (Epo) concentration of the heifer (20.7 mIU/ml) was similar to that observed in normal control heifers. Blood gas examinations of the arterial and venous blood revealed low levels of partial pressure O(2) (PaO(2)), partial pressure CO(2) (PaCO(2)) and O(2) saturation (SaO(2)), while the blood pH was within the normal range. Gross lesions could not be detected. However, microscopic observation revealed severe proliferation of erythroblasts in the bone marrow and in the spleen without evidence of neoplastic changes. Based on these clinical and pathological examinations, we diagnosed the heifer as being the first case of primary erythrocytosis in Japanese Black cattle.     

Optic pathway degeneration in Japanese black cattle

Degeneration of the optic pathway has been reported in various animal species including cattle. We experienced a case of bilateral optic tract degeneration characterized by severe gliosis in a Japanese black cattle without any obvious visual defects. To evaluate the significance, pathological nature and pathogenesis of the lesions, we examined the optic pathway in 60 cattle (41 Japanese black, 13 Holstein and 6 crossbreed) with or without ocular abnormalities. None of these animals had optic canal stenosis. Degenerative changes with severe gliosis in the optic pathway, which includes the optic nerve, optic chiasm and optic tract, were only observed in 8 Japanese black cattle with or without ocular abnormalities. Furthermore, strong immunoreactivity of glial fibrillary acidic protein was observed in the retinal stratum opticum and ganglion cell layer in all 5 cattle in which the optic pathway lesions could be examined. As etiological research, we also examined whether the concentrations of vitamin A and vitamin B12 or bovine viral diarrhea virus (BVDV) infection was associated with optic pathway degeneration. However, our results suggested that the observed optic pathway degeneration was probably not caused by these factors. These facts indicate the presence of optic pathway degeneration characterized by severe gliosis that has never been reported in cattle without bilateral compressive lesions in the optic pathway or bilateral severe retinal atrophy.     

Encephalitic sarcocystosis in a newborn calf

Sporozoan schizonts were seen in histologic sections of cerebrum from a Hereford calf that died immediately after birth. Schizonts appeared in endothelial cells of small vessels in the gray and white matter. Rosette and palisade configurations of merozoites in schizonts, as well as the size of schizonts (15 to 40 X 21 microns) and merozoites (8 microns), resembled Sarcocystis stages described in cattle, and differentiated the organisms from Toxoplasma that infects nerve cells and undergoes endodyogeny. Specific identification of the infecting agent was not successful because tests of sera from the calf were not possible. Developmental, morphologic, and ultrastructural differences in schizogonic stages of the heteroxenous sporozoan species infecting cattle are poorly known and are presently unreliable criteria for species identification. Encephalitis, meningitis, and necrosis occurred in cerebral, cerebellar, and brain stem gray and white matter infiltrated with plasmacytes, lymphocytes, and macrophages. Microthrombi were often seen in small blood vessels within the reaction foci. Herd-mate sera tested against S cruzi were negative. The herd from which the calf was born was exposed to a variety of free-ranging domestic, feral, and wild scavengers with free access to dead range animals. Consequently, the cattle were undoubtedly exposed to infective cysts in feed or water contaminated by feces from carnivores.     

Brain abscess in a Japanese black calf: utility of computed tomography (CT)

Computed tomography (CT) was used for diagnosis of brain abscess in a 6-month-old, Japanese black calf presented with neurological dysfunction, compulsive circling and vision disturbance. CT images showed asymmetric lateral ventricles, and presence of intra-cranial multiple low absorption lesions surrounded by capsule suggestive of abscess in the right cerebral hemisphere. Postmortem examination revealed marked swelling of right cerebral hemisphere and olfactory bulb. Multilocular large abscess containing creamy pus was found to occupy most area of periventricular and lateral ventricle. Fusobacterium necrophrum was isolated from the abscess contents as the causative agent. These results demonstrate that CT is useful tool for tentative diagnosis of bovine brain abscess.     

Fibrous vaginal hamartoma in a newborn calf

A 2-day-old female Holstein calf was presented for abnormal structures protruding from the vulva at birth. A diagnosis of fibrous vaginal hamartoma was made, based on macroscopic and histologic examinations of the abnormal tissue. Management of this case involved surgical mass ablation.     

Spinal dysraphism in a newborn Holstein-Friesian calf

Spinal dysraphism, not associated with vertebral defect or arthrogryposis, was found in a 3-day-old Holstein-Friesian calf that was clinically diagnosed as having encephalopathy. The dysraphic lesion occurred in the sixth (C6) and seventh (C7) segments of the cervical spinal cord. Microscopically, the lesion was characterized by hydromyelia, syringomyelia, anomaly of the ventral median fissure, abnormal running of the myelinated nerve fibers in the white column, and absence of the central canal due to a developmental defect of the ependymal cells.     

Congenital hepatic fibrosis in a newborn calf

Congenital hepatic fibrosis was observed in a newborn calf. Light microscopy revealed that periportal areas were linked via connective tissue to the central vein regions and to other periportal areas. Hyperplastic fibers were positive for type I collagen. A remarkable increase in the number of myofibroblasts that were positive for alpha-smooth muscle actin and vimentin was observed in the inner wall of the sinusoids, indicating the occurrence of various fibrogenesis. Ultrastractually, foci of cells resembling cholangiole epithelium cells were observed within the sinusoids, thereby suggesting either ductal plate dysplasia or a bile duct anomaly.     

Diffuse cutaneous mastocytosis in a newborn calf

Previously reported cases of congenital cutaneous mast cell tumours in calves were characterized by multiple discrete nodules. The calf presented herein is, to the authors' knowledge, the first documented case of congenital diffuse cutaneous mastocytosis. The entire skin was thickened and wrinkled with particularly prominent skin folds on the head, ventrum, and legs. Histological examination of two haired skin specimens (eyelid, muzzle margin) revealed that the dermis was diffusely infiltrated by sheets of neoplastic mast cells.     

Bovine viral diarrhea in a newborn calf

Bovine viral diarrhea virus was believed to be the cause of ill-thrift since birth, resulting in death of a Holstein calf. Bovine viral diarrhea virus was isolated from Peyer's patches and mesenteric lymph nodes, but serum neutralizing antibodies were not detected. The lymphoid depletion and myeloid suppression seen in this case may be a factor in the immune system dysfunction described for bovine viral diarrhea. Typical ulcerative lesions within the alimentary tract were not observed.     

Unilateral notomelia in a newborn Holstein calf

A 24-hour-old Holstein bull calf with notomelia was donated to the Atlantic Veterinary College. The extra limb was on the right side of the caudal neck adjacent to the withers. The limb was surgically removed under general anesthesia. The calf was adopted and discharged with no complications.     

A case of congenital unilateral hip dysplasia in a newborn calf

We describe the case of a Simmental calf with congenital unilateral hip dysplasia. In the initial physical exam, the calf was able to stand unsteady when helped and showed severe swinging lameness in the left hind limb. Unilateral hip laxity and a positive Ortolani sign indicated subluxation of the femur within the hip joint. This finding was further confirmed by radiographic examination which also showed malformation of the left femoral head and acetabulum. After a short period of clinical improvement the calf's health deteriorated and it was euthanized due to signs of severe coxarthrosis. Pathological examination of the affected hip joint revealed a severe acetabular and femoral dysplasia with an incomplete formation of the epiphysis of the femoral head and a chronic granulating coxarthritis without evidence of primary infectious events.     

Changes in peripheral leukocyte populations of weak calf syndrome of Japanese black calves

To clarify the cellular immune condition in Japanese Black (JB) calves with a weak syndrome, peripheral leukocyte populations were analyzed by flow cytometry. Twenty JB calves were divided into two groups based on clinical observations; one group of calves was weak, because they had experienced an onset of diarrhea within 3 days after birth and needed treatment (Group 1 ;n=10), and the other group of calves was healthy (Group 2; n=10). With regard to leukocyte populations, CD8(+) cells and gamma delta T cells in Group 1 were markedly lower than those in Group 2 during the experimental periods. It is possible that immune-insufficiency might be based on T lymphocyte function in weak syndrome JB calves during the growth process.     

A clinical case of a subepiglottic cyst in a Japanese Black calf

A 36-day-old Japanese Black calf exhibited wheezing associated with dyspnea from birth. Arterial blood gas analysis revealed a low oxygen partial pressure of 51 mmHg, low oxygen saturation of 83%, and high carbon dioxide partial pressure of 58.8 mmHg. Computed tomography, endoscopy, and ultrasonography showed cyst formation under the epiglottis. When the cyst was aspirated under ultrasonic guidance to secure the airway, 30 ml of viscous white turbid content was aspirated. The cyst shrank immediately after aspiration, but the wheezing and respiratory symptoms resumed 7 days after aspiration. Therefore, the cyst was surgically removed from the ventral side of the neck. No cyst remodeling was observed 30 days after surgical removal.