Carbon and nitrogen losses through moulting in the Cape rock lobster Jasus lalandii

Moulting data were collected from a size range of J. lalandii in an aquarium where field conditions of light intensity and temperature were simulated. Elemental analysis was carried out on intermoult exoskeleton, exuviae and whole lobsters. Lobsters lose a mean of 27% of their dry mass per year at ecdysis. Exuviae contained a higher ash content, a 28,1 % lower organic carbon content indicating reabsorption, and a similar inorganic carbon content when compared with intermoult exoskeleton. Estimates for a lobster population occupying 100 m2 at Robben Island are that 228 g organic carbon and 57,3 g nitrogen are lost annually. However, the annual cost of moulting to J. lalandii in terms of exuvial mass, which includes carbon and nitrogen, is considerable when viewed in terms of lost production

Burrow identification of some estuarine organisms

The available literature lacks adequate descriptions for the identification of the burrows of common South African estuarine benthic organisms. The burrows of three crab, two prawn, two bivalve and a polychaete species commonly encountered in southem Gape estuaries are described. Details on tidal levels, sediment types and associated macrophytes are included to assist in burrow identification

Monoclonal auto-antibodies and sera of autoimmune patients react with Plasmodium falciparum and inhibit its in vitro growth

The relationship between autoimmunity and malaria is not well understood. To determine whether autoimmune responses have a protective role during malaria, we studied the pattern of reactivity to plasmodial antigens of sera from 93 patients with 14 different autoimmune diseases (AID) who were not previously exposed to malaria. Sera from patients with 13 different AID reacted against Plasmodium falciparum by indirect fluorescent antibody test with frequencies varying from 33-100%. In addition, sera from 37 AID patients were tested for reactivity against Plasmodium yoelii 17XNL and the asexual blood stage forms of three different P. falciparum strains. In general, the frequency of reactive sera was higher against young trophozoites than schizonts (p < 0.05 for 2 strains), indicating that the antigenic determinants targeted by the tested AID sera might be more highly expressed by the former stage. The ability of monoclonal auto-antibodies (auto-Ab) to inhibit P. falciparum growth in vitro was also tested. Thirteen of the 18 monoclonal auto-Ab tested (72%), but none of the control monoclonal antibodies, inhibited parasite growth, in some cases by greater than 40%. We conclude that autoimmune responses mediated by auto-Ab may present anti-plasmodial activity

Oil Pollution of the Cape Infanta Coastline

Observations on oil pollution over the past 24 years have been made along the Cape Infanta coastline. Although no shipping disasters have occurred in the area, the oil cover of the rocks has increased markedly in places, with signs of affecting the intertidal fauna. It is concluded that the cumulative pollution by oil under present conditions may in time produce results similar to those encountered after large oil spills

The Effect of Oil Pollution from the Tanker “Wafra” on the Marine Fauna of the Cape Agulhas Area

Much was learnt of the effect of oil pollution and the dangers of surfactants from the Torrey Canyon disaster off the Cornish coast in 1967 and a useful introduction to the problem of oil pollution will be found in Carthy and Arthur (1968). Since that date, the chemical composition of surfactants has been improved and there are now better methods of applying them. It is well known that hydrological conditions around South African coasts are different from those in the English Channel and that the marine fauna and flora is quite distinct. No scientific account of the biological effects of oil pollution in South Africa has been published and it is hoped that the following observations of the effects of oil spillage on the Cape Agulhas coast will indicate what may be expected when future oil spillages occur. Considering the volume of oil traffic around the Cape of Storms such an event seems inevitable