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Soil fungi, including Aspergillus fischeri, Penicillium piceum, Penicillium nigricans, and Penicillium raistrickii, produced a tremorgenic toxin previously described as toxin X. Chemical analysis showed that this toxin was predominantly verruculogen.

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PLATE XXXIII SHREEVE A N D THOMLINSON (1970a and b) have shown thatEscherichia coli disease in the young piglet has several features in common with oedema disease of the older pig, and that the lesions bear a close resemblance to those associated with anaphylactic reactions (Thomlinson and Buxton, 1962, 1963 ; Thomlinson, 1963). The work described in the present paper formed part of an investigation into the pathogenesis of E. coli disease in young piglets and its purpose was to determine whether exposure of pregnant sows to an antigenic substance may lead to hypersensitivity in their piglets. Hen-egg albumin was chosen for the immunisation of sows in these experiments, because this was an antigen to which the animals had not previously been exposed. MATERIALS AND METHODSOrigin of animals. Pregnant Large White sows were obtained from a herd that was known to maintain a good standard of husbandry and health, and were maintained on a commercial sow diet. All piglets were separated from the sow at birth and before they had ingested colostrum. Blood samples were collected, then approximately half the piglets in each litter were returned to the sows for 24 hr; these were the " colostrum-fed " experimental group. The remainder of the piglets were housed separately in cages and were the " colostrum-deprived " group. Experiments on these piglets were carried out as soon as possible after birth.Collection of blood samples and colostral whey samples. All blood samples from piglets were obtained from the anterior vena cava (Mackenzie, 1961) and a maximum of 4 ml of whole blood was withdrawn at one time. Blood samples from sows were obtained from an auricular vein. Whey was separated from fresh samples of colostrum by the method described by Sharpe (1965). Samples of serum and whey were stored at -30°C.Imrnunisation of sows. A 5 per cent. solution of hen-egg albumin was prepared in sterile normal saline and centrifuged to remove any undissolved particles; 5 ml of this solution was injected intravenously into an auricular vein in each of five pregnant sows. This injection was repeated with freshly prepared egg albumin solution after 7, 9, 1 1 , 13, 15, 17, 19 and 26 days, the final injection being given 10 days before the expected farrowing date.Preliminary experiments showed that as much as 50 mg hen-egg albumin dissolved in 0.1 ml normal saline could be injected intradermally into normal piglets whose darns had not been immunked, without provoking any reaction. Doses of 10 mg, 5 mg and 1 mg dissolved in 0.1 ml normal saline were chosen for use in the experiments. A 26-SWG hypodermic needle was used and the injections were made 5 cm below the dorsal border of the neck and 2.5 cm behind the base of the ear. Egg albumin was Inrradermul tests in piglets.