Certain cytologic features of the porcine adrenal medulla

Adrenal glands were collected from pigs of various ages under general anesthesia. Glutaraldehyde-fixed medullary tissue was postfixed with OsO4 for electron microscopy and with potassium dichromate or potassium iodate for light microscopy. Columnar epinephrine (E) cells formed cords between wide sinusoidal capillaries at the corticomedullary junction and were arranged in palisade fashion along the central vein and its major tributaries. The E cells usually were polarized, with the nuclei located away from the sinusoidal capillaries. Clusters of polygonal norepinephrine (NE) cells formed large central aggregates surrounded by E cells. Granulated vesicles were the predominant cytoplasmic feature of both E and NE cells. Round or oval E granules were bounded by a crenated membrane separated from the granule by a clear halo. The more electron-dense, elongate NE granules were bounded by a closely apposed, smooth membrane. The average longest granule axis was 270 nm for E granules and 305 nm for NE granules. Many cytoplasmic organelles were congregated in a granule-free paranuclear zone, which contained a prominent Golgi complex. Thin nonmyelinated nerve fibers (singly or in small groups) were interposed between the E and NE cells. Nerve fibers often were located close to the nucleus in a depression of the cell surface and often were wrapped by thin E or NE cell processes. The medulla of newborn pigs was composed predominantly or exclusively of NE cells. In both adults and pigs, E or NE cell cords radiated through the cortex toward the capsule, and isolated clusters of E or NE cells frequently were found in the capsule or zona glomerulosa.     

Neuronal ceroid-lipofuscinosis in Borderdale sheep

AIM: To describe the gross and histological lesions of a neurological disease in Borderdale sheep characterised clinically by blindness and circling, as a basis to its classification. METHODS: Formalin-fixed tissues were processed into paraffin wax and epoxy resin for light and electron microscopy of variously stained sections. RESULTS: Lesions were those of a lysosomal storage disease with severe neurodegeneration of the cerebral cortex. The staining reactions, autofluorescence and ultrastructure of storage material allowed the diagnosis of neuronal ceroid-lipofuscinosis associated with the accumulation of subunit-c of mitochondrial ATP synthase. CONCLUSIONS: The severity of neurodegeneration and minor differences in the ultrastructure of storage material implied that this was a different disease from other forms of ovine ceroid-lipofuscinosis that accumulate subunit-c of mitochondrial ATP synthase. An autosomal recessive mode of inheritance is considered probable. Although of only minor economic importance, this disease may be important to research into the group of ceroid-lipofuscinoses as a whole.     

Serological study of leptospiral infections and endogenous uveitis among horses and ponies in the United Kingdom

The prevalence of antibody titres to a range of 20 leptospira antigens in the serum of horses and ponies with no ophthalmic abnormalities and with ophthalmoscopic evidence of endogenous uveal inflammatory disease was determined using a microscopic agglutination technique. Titres against leptospira antigens were observed in 13 out of 138 (9.1 per cent) animals with no ophthalmic abnormalities, and in three out of 27 (11.1 per cent) animals with anterior uveitis. Serovar sejroe was common to all seropositive animals with anterior uveitis. The results show that leptospira infection is not a major factor in the aetiology of equine anterior uveitis in the UK, but suggests that the organism may be associated with some cases of recurrent anterior uveitis.     

Congenital deafness and vestibular deficit in the dobermann

A condition characterised by the early onset of vestibular deficit and hearing loss was investigated in the dobermann breed of dog. Affected pups showed behavioural signs of head tilt, circling and ataxia and there was a total absence of vestibular response to rotation or caloric stimulation. Severe deafness, as assessed by brainstem auditory evoked response testing, was present by three weeks of age in all affected animals. The inner ears showed a progressive neuroepithelial type of cochlear degeneration with loss of the auditory sensory cells. In the vestibular system, however, there was no equivalent sensory cell loss and the only abnormal feature was the absence or abnormality of the otoconia in some of the affected animals. Pedigree analysis suggested that the condition was inherited as an autosomal recessive trait.     

Effect of source of calcium and phosphate,autoclaving, vitamin D3 level and strain of turkey poults on the rachitogenic activity of isolated soybean protein 1

This study was conducted to ascertain the effect of autoclaving, source of calcium and phosphate, vitamin D₃ level and strain of turkey poults on the rachitogenic activity of isolated soybean protein (C‐1 protein‐Skidmore). One‐day‐old poults were fed purified diets of the glucose—C‐1 protein type. The diets contained calcium, phosphorus and vitamin D₃ at levels equal to or greater than the National Research Council's (1960) recommendations. The findings demonstrate that USP hydrated dicalcium phosphate was more effective than food‐grade dicalcium phosphate in overcoming the rachitogenic activity of the C‐1 protein. Autoclaving the C‐1 protein for 80 min destroyed its rachitogenic activity: Vitamin D₃ was also effective in reducing the rachitogenic effect of C‐1 protein. The Broad Breasted White strain proved to be more susceptible to the rachitogenic property of C‐1 protein than the Wrolstad Small White strain. Substituting USP hydrated dicalcium phosphate for food‐grade dicalcium phosphate, autoclaving the C‐1 protein or increasing the vitamin D₃ level increased body weight gains and tibia ash values. The interactions which were shown to exist between source of calcium and phosphate × autoclaving, strain × autoclaving, and vitamin D₃ level × strain demonstrate an interrelationship between these factors.