The vertebrate gastrointestinal tract is populated by bacteria and, in some species, protozoa and fungi that can convert dietary and endogenous substrates into absorbable nutrients. Because of a neutral pH and longer digesta retention time, the largest bacterial populations are found in the hindgut or large intestine of mammals, birds, reptiles, and adult amphibians and in the foregut of a few mammals and at least one species of bird. Bacteria ferment carbohydrates into short-chain fatty acids (SCFA), convert dietary and endogenous nitrogenous compounds into ammonia and microbial protein, and synthesize B vitamins. Absorption of SCFA provides energy for the gut epithelial cells and plays an important role in the absorption of Na and water. Ammonia absorption aids in the conservation of nitrogen and water. A larger gut capacity and longer digesta retention time provide herbivores with additional SCFA for maintenance energy and foregut-fermenting and copoprophagic hindgut-fermenting species with access to microbially synthesized protein and B vitamins. Protozoa and fungi also contribute nutrients to the host. This review discusses the contributions of gut microorganisms common to all vertebrates, the numerous digestive strategies that allow herbivores to maximize these contributions, and the effects of low-fiber diets and discontinuous feeding schedules on these microbial digestive processes.

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Traditional political risk theories often focus on a developing host country government's ability to intervene in the activities of foreign multinationals in the extractive or infrastructure sectors. This results in inadequate understanding of (1) how a government's motivation to intervene is influenced by the broader societal context, (2) the importance of multinationals' political risk at home, and (3) the increasing political risk faced by high‐tech and service firms. We argue that there is a need to update the bargaining power and political institutions theories and further develop a legitimacy‐based view of political risk. Then, we examine the political risk experienced by Google and Yahoo at home and abroad due to their activities in China to illustrate the benefits of a holistic approach to political risk. Copyright © 2015 John Wiley & Sons, Ltd.

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Twelve swine were used to assess the movement of fluid and particulate digesta through their gastrointestinal tracts and to determine the diurnal variations in organic acid levels for various segments of the tract. Animals were fed twice daily at 12-hour intervals. Fluid (polyethylene glycol and chromium-labeled ethylenediamine-tetraacetic acid) and particulate markers (2 mm OD, and 2 mm and 1 and 2 cm long) were administration of markers. The gastrointestinal tract was divided into 12 segments for measurements of markers, pH, volatile fatty acids (VFA), and lactic acid (LA) contents. The data indicated a rapid evacuation of the fluid and the smaller particles from the stomach and their relatively rapid passage through the small intestine and cecum. There was, however, prolonged retention of both fluid and particulate markers first in the ascending and then in the descending colon. Larger particles (2 cm) were retained in the stomach throughout much of the 60-hour experimental period. LA levels were observed 8 hours postfeeding. The highest levels of VFA in gastric contents averaged 20 mmoles/liter. Gastrointestinal pH values showed significant changes with time postfeeding only within the stomach, where they did not reflect the changes in LA of VFA concentrations. VFA constituted 92% of the organic acids present in the large intestine. Their concentrations varied markedly with time (150-230 mmoles/liter), but the VFA at all times constituted the major anions in the large intestinal contents. The results demonstrated that digesta can be retained for prolonged periods of time in that swine stomach and colon. The high concentrations of organic acids also indicated that substantial degrees of microbial digestion of carbohydrates occurred at both sites.

Sixteen geese were used to assess the movement of fluid and particulate digesta through their gastrointestinal tracts and to determine the diurnal variation in organic acid levels for the various segments of the tract. Fluid (polyethylene glycol and chronium-labeled ethylenediaminetetraacetic acid) and particulate markers (2 and 5 mm long) were administered with the meal. Animals were killed at given intervals after the administration of markers. The gastrointestinal tract was divided into nine segments for measurement of markers, pH, volatile fatty acids (VFA), and lactic acid contents. The data indicated a rapid evacuation of fluid marker from the foregut (crop, ventriculus, and proventriculus), while particulate markers were retained for extended periods of time. Retention of fluid marker was observed only within the cecum. Retrograde movement of particulate marker was demonstrated from the duodenum to ventriculus and proventriculus. Retrograde movement of fluid marker was observed from the cloaca to the colon, cecum, and distal third of the small intestine. However, particulate marker showed no retrograde movement in these segments of tract. Highest VFA levels were observed in the cecum. Retention of digesta and production of VFA within the colon were less than those noted for the dog, pig and pony. Lactic acid comprised less than 10% of the organic acids present in the gastrointestinal tract and were at their highest levels in the proximal and mid small intestine.

Research Summary In order to successfully invest abroad, firms must consider how their actions will affect their acceptance by host country stakeholders such as the government and host society. When perceived as more legitimate, firms will likely experience less political risk; greater illegitimacy will likely result in more political risk. Importantly, such stakeholders often form similar opinions about firms from the same home country—resulting in legitimacy spillovers within a given host environment across similar firms. Moreover, stakeholders in one country form opinions of firms based on their actions in other countries, resulting in across‐country legitimacy spillovers. This article examines legitimacy and illegitimacy spillovers encountered by Chinese, American, Indian, and European firms in East Africa, which resulted in differences in their acceptance and their political risk. Managerial summary Although the literature has begun to consider how firms’ legitimacy affects their political risk, the role of legitimacy spillovers has not been addressed. Using the legitimacy‐based view of political risk and the literature on cognition and social judgments, we develop theory about how within‐country and across‐country spillovers of legitimacy (or illegitimacy) based on firms’ home country origins can affect their political risk. We examine the case of FDI in six East African countries that have experienced a rapid increase in foreign investment despite the presence of political risk. This case shows evidence of legitimacy spillovers resulting in systematic variation in firms’ political risk. Moreover, we find an important role for moderating factors such as the media, historical ties, and distance between countries. Copyright © 2016 John Wiley & Sons, Ltd.