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Metalliferous mineral deposits of the Cascade range in Oregon, by Eugene Callaghan and A. F. Buddington. Prepared in cooperation with the State mining board of Oregon
This report deals with a group of mineralized areas containing Tertiary veins of base metal and gold,· which occur at intervals throughout the Cascade Range in Oregon. Gold was discovered in this region in 1858, only a few years after its discovery in southwestern Oregon, and an output of nearly $1,000,000, almost entirely in gold, has been recorded. The gold was mined largely from the weathered parts of the veins; placer production has been negligible. Other metalliferous deposits include nodules of native copper between lava flows, nodules of manganese oxides, and deposits of quicl{silver along the western margin of the Cascade Range.Gerald W. Williams Collectio
Changes in gut gross morphology of traÃra, Hoplias malabaricus (Teleostei, Erythrinidae) during long-term starvation and after refeeding
Isolated Rearing at Lactation Increases Gut Microbial Diversity and Post-weaning Performance in Pigs
Environment and diet are two major factors affecting the human gut microbiome. In this study, we used a pig model to determine the impact of these two factors during lactation on the gut microbiome, immune system, and growth performance. We assigned 80 4-day-old pigs from 20 sows to two rearing strategies at lactation: conventional rearing on sow’s milk (SR) or isolated rearing on milk replacer supplemented with solid feed starting on day 10 (IR). At weaning (day 21), SR and IR piglets were co-mingled (10 pens of 4 piglets/pen) and fed the same corn-soybean meal-dried distiller grain with solubles- and antibiotic-free diets for eight feeding phase regimes. Fecal samples were collected on day 21, 62, and 78 for next-generation sequencing of the V4 hypervariable region of the bacterial 16S rRNA gene. Results indicate that IR significantly increased swine microbial diversity and changed the microbiome structure at day 21. Such changes diminished after the two piglet groups were co-mingled and fed the same diet. Post-weaning growth performance also improved in IR piglets. Toward the end of the nursery period (NP), IR piglets had greater average daily gain (0.49 vs. 0.41 kg/d; P < 0.01) and average daily feed intake (0.61 vs. 0.59 kg/d; P < 0.01) but lower feed efficiency (0.64 vs. 0.68; P = 0.05). Consequently, IR piglets were heavier by 2.9 kg (P < 0.01) at the end of NP, and by 4.1 kg (P = 0.08) at market age compared to SR piglets. Interestingly, pigs from the two groups had similar lean tissue percentage. Random forest analysis showed that members of Leuconostoc and Lactococcus best differentiated the IR and SR piglets at weaning (day 21), were negatively correlated with levels of Foxp3 regulatory T cell populations on day 20, and positively correlated with post-weaning growth performance. Our results suggest that rearing strategies may be managed so as to accelerate early-life establishment of the swine gut microbiome to enhance growth performance in piglets
The Effect of Feeding Bt MON810 Maize to Pigs for 110 Days on Intestinal Microbiota
Objective: To assess the effects of feeding Bt MON810 maize to pigs for 110 days on the intestinal microbiota. Methodology/Principal Findings: Forty male pigs (,40 days old) were blocked by weight and litter ancestry and assigned to one of four treatments; 1) Isogenic maize-based diet for 110 days (Isogenic); 2) Bt maize-based diet (MON810) for 110 days (Bt); 3) Isogenic maize-based diet for 30 days followed by a Bt maize-based diet for 80 days (Isogenic/Bt); 4) Bt maizebased diet for 30 days followed by an isogenic maize-based diet for 80 days (Bt/Isogenic). Enterobacteriaceae, Lactobacillus and total anaerobes were enumerated in the feces using culture-based methods on days 0, 30, 60 and 100 of the study and in ileal and cecal digesta on day 110. No differences were found between treatments for any of these counts at any time point. The relative abundance of cecal bacteria was also determined using high-throughput 16 S rRNA gene sequencing. No differences were observed in any bacterial taxa between treatments, with the exception of the genus Holdemania which was more abundant in the cecum of pigs fed the isogenic/Bt treatment compared to pigs fed the Bt treatment (0.012 vs 0.003%; P#0.05). Conclusions/Significance: Feeding pigs a Bt maize-based diet for 110 days did not affect counts of any of the culturable bacteria enumerated in the feces, ileum or cecum. Neither did it influence the composition of the cecal microbiota, with the exception of a minor increase in the genus Holdemania. As the role of Holdemania in the intestine is still under investigatio
Intestinal microbiota in human health and disease: the impact of probiotics
The complex communities of microorganisms that colonise the human gastrointestinal tract play an important role in human health. The development of culture-independent molecular techniques has provided new insights in the composition and diversity of the intestinal microbiota. Here, we summarise the present state of the art on the intestinal microbiota with specific attention for the application of high-throughput functional microbiomic approaches to determine the contribution of the intestinal microbiota to human health. Moreover, we review the association between dysbiosis of the microbiota and both intestinal and extra-intestinal diseases. Finally, we discuss the potential of probiotic microorganism to modulate the intestinal microbiota and thereby contribute to health and well-being. The effects of probiotic consumption on the intestinal microbiota are addressed, as well as the development of tailor-made probiotics designed for specific aberrations that are associated with microbial dysbiosis
The emplacement of acid magma in the epizone, and the relationship with ignimbrites, in North Queensland, Australia
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