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The present study was performed to assess the effects of diets supplemented with low (5%) and high (20%) corn oil on a Pts 56 retrovirus-induced model of pancreatic carcinogenesis in guinea fowl. The early microscopic lesions appear after 3 mo after virus treatment and progress over time. Eight to 10 mo after initiation, up to 100% of virus-inoculated birds develop multiple hyperplastic and neoplastic pancreatic lesions of duct/ductular phenotype. Short-term (1-4 mo) feeding of low- or high-fat diets, beginning at Month 3, had no significant effects on body and pancreatic weight. However, the incidence, multiplicity, and areas of the pancreatic tissue occupied by intra- and interlobular aggregates of hyperplastic ducts with mucinous metaplasia of the lining cells were significantly increased compared with the birds fed the common diet. At the same time, development of ductular neoplasms, particularly carcinomas, was retarded compared with the common diet-fed controls. Long-term (5-7 mo) fat intake resulted in an increase in body weight gain, while absolute pancreatic weights remained relatively constant. Furthermore, the high- and low-fat diets caused a significant increase in areas of retrovirus-induced pancreatic lesions, as well as an increase in multiplicity of ductular neoplasms compared with short-term fat feeding. It is concluded that short-term feeding of diets supplemented with 5% or 20% corn oil delayed the development of the common virus-induced ductular neoplasms, particularly carcinomas, and had an enhancing effect on development of hyperplastic inter- and intralobular aggregates of ducts. This finding was not observed, however, during the long-term feeding period of the study.

The locality of Langenboom (eastern Noord-Brabant, the Netherlands), also known as Mill, is famous for its Neogene molluscs, shark teeth, teleost remains, birds and marine mammals. The stratigraphic context of the fossils, which have been collected from sand suppletions, was hitherto poorly understood. Here we report on a section which has been sampled by divers in the adjacent flooded sandpit 'De Kuilen' from which the Langenboom sands have been extracted. The studied section covers part of the marine Miocene Breda Formation and Pliocene Oosterhout Formation, and is topped by fluvial Quaternary deposits of presumably the Beegden Formation. The Breda Formation (15 - 18 m below lake surface) in this section is, based on organic walled dinoflagellate cysts, of an early-middle Tortonian age. The Oosterhout Formation (7 - 15 m below lake surface) comprises two depositional sequences, the lower of which (12 - 15 m below lake surface) presumably is the source of most Langenboom fossils. Combined dinoflagellate cyst and benthic mollusc indicators point to an early Zanclean - early Piacenzian age for this lower cycle. Its basal transgressive lag and (to lesser extent) top comprise reworked Tortonian taxa as well. Dinoflagellate cysts and a single benthic mollusc point to a Piacenzian age for the upper Oosterhout Formation sequence (7 - 12 m below lake surface).

A study was conducted with conventional and germ-free broiler chicks to obtain more information on the role of the intestinal microflora in the anti-nutritive effects of NSP in broiler chicks. As the NSP source, highly methylated citrus pectin (HMC) was used at a dose level of 30 g/kg in a maize-based diet. The diets fed to the germ-free chicks were γ-irradiated, whereas those fed to the conventional chicks were not. Feeding the HMC diet to conventional birds depressed weight gain and food utilization (P < 0.05), whereas in germ-free birds only weight gain was reduced (P < 0.05). Feeding the HMC diet to conventional birds reduced digestibilities of energy and starch at the end of the jejunum. Ileal digestibilities of starch and energy were not strongly affected when birds were fed on the HMC-containing diet. Faecal digestibilities of organic matter, crude fat, starch and amino acids, N retention and metabolizable energy were reduced when conventional chicks were fed on the HMC diet. Feeding the HMC diet to germ-free birds hardly affected faecal digestibility of nutrients and N retention, whereas metabolizable energy was increased. Feeding the HMC diet to conventional or germ-free birds increased the viscosity of the digesta in the small intestine. This increase in digesta viscosity was more pronounced in conventional than in germ-free birds. The pH of ileal digesta was reduced when HMC was added to the diet of conventional chicks, but not in germ-free chicks. Feeding the HMC diet to conventional birds markedly affected morphology of the gut wall, whereas in germ-free chicks very little effect was found on gut morphology. Based on the results of the present study, it is concluded that the gastrointestinal microflora mediates the magnitude of the anti-nutritive effects of HMC in broiler chicks. However, the exact role of the microflora in chicks in the magnitude of the anti-nutritional effects of HMC could not be derived from the present study, since the results might have been influenced by γ-irradiation of the diets fed to the germ-free chicks. Chemicals/CAS: Nerve Tissue Proteins; Pectins