Sheep brain

Provitamin D. Provitamin is made from cholesterol, and its commercial production begias with the isolation of cholesterol from one of its natural sources. Cholesterol occurs ia many animals, and is generally extracted from wool grease obtained by washing wool after it is sheared from sheep. This grease is a mixture of fatty-acid esters, which contain ca 15 wt % cholesterol. The alcohol fraction is obtained after saponification, and the cholesterol is separated, usually by complexation with 2iac chloride, followed by decomplexation and crystallisation. Cholesterol can also be extracted from the spiaal cords and brains of animals, especially catde, and from fish oils. 

In the early 1930 s, when the prime research aim was the commercial synthesis of the sex hormones (whose structures had just been elucidated), the principal raw material available was cholesterol extracted from the spinal cord or brain of cattle or from sheep wool grease. This sterol (as its 3-acetate 5,6-dibromide) was subjected to a rather drastic chromic acid oxidation, which produced a variety of acidic, ketonic and hydroxylated products derived mainly by attack on the alkyl side-chain. The principal ketonic material, 3j -hydroxyandrost-5-en-17-one, was obtained in yields of only about 7% another useful ketone, 3 -hydroxypregn-5-en-20-one (pregnenolone) was obtained in much lower yield. The chief acidic product was 3j -hydroxy-androst-5-ene-17j -carboxylic acid. All three of these materials were then further converted by various chemical transformations into steroid hormones and synthetic analogs ... 

There has been great concern over the large-scale outbreak of BSE that occurred in the UK from 1988 as a result of feeding cattle with supplements prepared fiom sheep and cattle offal. Brain extracts firm BSE cattle have transmitted the disease to mice, sheep, cattle, pigs and monkeys. Studies of 12 recent cases of atypical CJD in the UK have provided evidence that the bovine prions have infected humans through the consumption of contaminated beef... 

Viruses replicate only in living cells so the first viral vaccines were necessarily made in animals smallpox vaccine in the dermis of calves and sheep and rabies vaccines in the spinal cords of rabbits and the brains of mice. Such methods are no longer used in advanced vaccine production and the only intact animal hosts that are used are embryonated hens eggs. Almost all of the vims that is needed for viral vaccine production is obtained from cell cultures infected with vims of the appropriate strain. 

A3 adenosine receptors are few in the central nervous system. In the rat, abundant A3 transcript is found exclusively in testes. However, the transcript for similar sheep and human receptors is modestly expressed throughout the brain and heavily expressed in pineal gland, lung and spleen. 

A number of animal diseases caused by viruses involve primary demyelination and often are associated with inflammation. These diseases are studied as animal models, which may provide clues about how a viral infection could lead to immune-mediated demyelination in humans [1, 5, 6]. Canine distemper virus causes a demyelinating disease, and the lesions in dog brain show a strong inflammatory response with some similarities to acute disseminated encephalomyelitis in man [ 1 ]. Visna is a slowly progressive demyelinating disease of sheep caused by a retrovirus [ 1 ]. 

Some deaths. Yellow discoloration of sclera of eye passing of red-colored urine. Copper concentrations, in mg/kg DW, from sheep fed nonheliotrope diets were 1394 in liver (824 in controls) and 132 in kidney (20 in controls). Sheep on heliotrope diet had 2783 mg/kg DW in liver and 321 mg Cu/kg DW in kidney Severe morphological changes in liver, kidney, and brain tissue damage continued after cessation of copper and was sufficiently severe to lead to repeated hemolytic crises. Maximum copper concentrations at day 83 were 3289 mg/kg DW in liver (138 in controls), and 683 in kidney (15 in controls)... 

Doherty, P.C., R.M. Barlow, and K.W. Angus. 1969. Spongy changes in the brains of sheep poisoned by excess dietary copper. Res. Veterin. Sci. 10 303-304. 

Some deaths. Residues (mg/kg fresh weight) >3 in brain, >10 in clotted heart blood, >6 in kidney, and up to 20 in liver Blood lead concentrations, in mg/L, increased from <0.1 at start to 0.1 after 24 h, 3.2 at 7 days, to 6.8 at 14 days. There were some deaths at day 21 and survivors had 0.6 mg Pb/kg blood FW. All dosed birds had immunosuppressive effects, as seen by lowered hemagglutination titers to sheep red blood cells... 

Single injection of radiolabeled famphur equivalent to 22.3 mg famphur/kg BW. Sheep killed at 96 h and tissues analyzed for residual radioactivity More than 50% of the administered dose was excreted within 6 h and 98% within 48 h. About 97% was excreted in urine and <3% in feces. Residues, in mg/kg FW, were 1.4 in blood 0.3-0.6 in kidney, liver, spleen, lung, and cerebrospinal fluid and <0.1 in bile, fat, brain, and muscle 7, 8... 

In sheep fed hexachloroethane in olive oil emulsified in water, the hexachloroethane was found primarily in the liver, kidneys, and adipose tissue 8 hours after exposure much smaller amounts were found in brain and muscle 8 hours after exposure. The maximum concentration of hexachloroethane in blood occurred 24 hours after dosing (Fowler 1969b). 

Both oral and inhalation exposures to high concentrations of hexachloroethane were associated with hyperactivity, ataxia, convulsions, and/or prostration in rats, sheep, and dogs. The mechanism for these neurological effects is not clear since there were no apparent histopathological lesions in the brains of the affected animals. Neurological effects were only noted with the high-dose exposures. 

Ataxia, tremors, and prostration in sheep given hexachloroethane (170 or 338 mg/kg) for a liver fluke infection were successfully ameliorated with calcium as calcium borogluconate. This suggests that the neurological action of hexachloroethane may be the result of interference with the availability of calcium within excitable cells. This mechanism would explain the transient nature of the hexachloroethane neurotoxicity and is compatible with the low affinity that hexachloroethane shows for brain tissue (Fowler 1969b). 

Gajendragad MR, Gopalakrishna S, Ravikumar SB. 1992. Pathology of the brain in acute hydrocyanic acid poisoning in sheep. Indian Vet J 69(3) 206-210. 

Mount ME, Oehme FW. 1981. Brain cholinesterase activity in healthy cattle, swine and sheep and in cattle and sheep exposed to cholinesterase-inhibiting insecticides. Am J Vet Kes 42 1345-1350... 

ACE has been used to characterize protein-sugar interactions,45 DNA binding to an anti-DNA monoclonal antibody,46 antibody-antigen47 antisteroidal inflammatory drugs,48 and prion protein in sheep brain preparations.49... 

Enzyme activity in sheep, marmoset, and human brain extracts. CYP7B mRNA in human hippocampus, cerebellum, cortex less in dentate neurons from Alzheimer s diseased subjects by in situ hybridization (Yau et al., 2003). 

Kendrick, K. M., Keverne, E. B., Chapman, C., and Baldwin, B. A. (1988). Microdialysis measurement of oxytoxcin, aspartate, gamma-aminobutiyic acid and glutamate release from the olfactory bulb of sheep during vaginocervical stimulation. Brain Research44l, 171-174. 

Transmissible spongiform encephalopathies (TSEs)—Brain diseases transmitted from one animal to another. Under a microscope, the brain tissue of animals and people with TSEs resembles a sponge. TSEs include variant Creutzfeldt-Jacob disease (vCJD) in humans, scrapie in sheep and goats, and bovine spongiform encephalopathy (BSE) in cows (mad cow disease). These diseases are spread by consumption of brain tissue and are thought to be caused by prions, a kind of protein. 

Da Costa, A.R, Broad, K.D., and Kendrick, K.M. (1997). Olfactory memory and maternal behaviour-induced changes in c-fos and zif/268 mRNA expression in the sheep brain. Brain Res Mol Brain Res, 46 63-76. 

Kendrick, K.M., Keverne, E.B., Hinton, M.R., and Goode J.A. (1992) Oxytocin, amino acid and monoamine release in the region of the medial preoptic area and bed nucleus of the stria terminalis of the sheep during parturition and suckling. Brain Res 569 199-209. 

Dockray GJ, Gregory RA, Hutchison JB, et al Isolation, structure and biological activity of two cholecystokinin octapeptides from sheep brain. Nature 274 711-713, 1978... 

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