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Three chicken Sox (SRY-like box) genes have been identified that show an interactive pattern of expression in the developing embryonic nervous system. cSox2 and cSox3 code for related proteins and both are predominantly expressed in the immature neural epithelium of the entire CNS of HH stage 10 to 34 embryos. cSox11 is related to cSox2 and cSox3 only by virtue of containing an SRY-like HMG-box sequence but shows extensive homology with Sox-4 at its C-terminus. cSox11 is expressed in the neural epithelium but is transiently upregulated in maturing neurons after they leave the neural epithelium. These patterns of expression suggest that Sox genes play a role in neural development and that the developmental programme from immature to mature neurons may involve switching of Sox gene expression. cSox11 also exhibits a lineage restricted pattern of expression in the peripheral nervous system.

The deduced amino-acid sequence of chick HoxB3 shows 70% homology to the murine HoxB3. The major difference is that the chick sequence lacks a run of Gly residues present in mouse and human HoxB3. The basic pattern of expression of HoxB3 in the embryonic nervous system is conserved between mice and chicks.

Veterinary educators all over the world are concerned about the explosion in knowledge and about the way veterinary science is taught at present. How can we produce veterinarians who will provide the sort of care that will be expected in the year 2000 and beyond? In the recent past many schools have increased the information presented in their courses without removing any material. Student stress has increased, and under-graduates do not retain what they are taught. The type of assessment that is currently used often requires regurgitation of 'facts' rather than the solution of problems. This paper considers some of the issues that are pertinent to the future of veterinary education and suggests ways in which the situation may be improved. There is a need for increased activity by the Australian Veterinary Association to convince government that present funding is inadequate and that increased funding is urgently needed if we are to produce veterinarians of the quality the country will need in the next century.

For effective cell yields in semi-industrial production of primary cell suspensions, the use of trypsin solutions with high enzyme activity has been proved to be an essential requirement. Enzyme solutions with a constant high activity may be obtained by using an optimal filtration method. Filtration results using the deep and membrane filtration method to sterilize trypsin solutions are demonstrated and discussed. A number of trypsin samples taken from the "Leidholdt-Firm" were tested concerning cell yields in the so-called 'Biomix-Procedure'. A correlation could be shown to exist between enzyme activity and cell yield. The so tested trypsin-L-samples out of the years 1976/78 were proved to be first-rate preparations for routine production of primary piglet and calf kidney cell cultures.

To produce large quantities of primary cell suspensions on efficient technique is described which is named "Biomix-Method". By this technique first tissue mince is performed automatically using tissue amounts between 300 g and 500 g. Trypsinization takes place in a three-litre trypsinization vessel using a stirring mechanism according to a defined trypsinization mode. In regard to optimal cell seeding concentration and a justifiable productivity one kidney of newborn or suckling calf yields 6--9 1 cell suspension and that of piglet 1,8-2,3 1, respectively. Proliferation behaviour and effectivity of primary cells are discussed and compared with other cell systems.