Comparative digestion studies in wild suids at Rotterdam Zoo

Among the artiodactyla, the suids are a group whose digestive physiology has hardly been investigated. The apparent digestibilities (aD) of macronutrients were measured in captive specimens of warthog (Phacochoerus africanus), red river hog (Potamochoerus porcus), and Visayan warty pigs (Sus cebifrons), and compared with those reported for babirusa (Babyrousa babyrussa) from the same facility on a similar diet. The animals were fed mixed diets of pelleted feed, grains, fruits, and vegetables; dietary neutral detergent fiber (NDF) ranged from 17 to 26% dry matter. aD of organic matter and protein ranged from 72 to 89 and 70 to 82%, respectively. Although red river hogs and warty pigs achieved aD of NDF of 41-54%, this value was higher both in warthogs (63-66%) and babirusa (61-63%). aD of acid detergent fiber was comparatively low in red river hogs (4%), warty pigs (22%), and babirusa (13-25%) but high in warthog (59-62%). Comparison with additional literature data (including peccaries) indicates that in spite of differences in digestive anatomy, suids and peccaries are similar, and resemble other herbivores in fundamental characteristics, such as the negative influence of fiber on overall digestibility, or the positive influence of dietary protein on protein digestion. Although the existing data are equivocal as to a superior fiber digestion in peccaries as compared with other wild suids, the results suggest that warthogs are more efficient than other wild suids or peccaries in terms of fiber digestion

Wood modification in relation to bridge design in the Netherlands

Recently a timber bridge for heavy traffic is realized in the Netherlands. The 32 meter long bridge spans the A7 highway in Sneek, one of the eleven cities of the world famous eleven cities skating race in Friesland. A second bridge, identical to the one described in the paper, is under construction. Other timber bridges, similar to these, are in the developing phase. Due to durability considerations these bridges cannot be designed without preservation or modification techniques. Since wood preservation is no longer highly appreciated, because of environmental issues, wood modification processes have been developed (and are still under development). However, during modification processes wood temperature rises and, in many circumstances, the strength and stiffness properties are affected. A so-called chemical modification process is chosen for the bridges described. The initial research for determining the influence of the modification process on the strength and stiffness properties is described. Furthermore, the design process in relation to the timber process is outlined

Influence of two different diets on fluid and particle retention time javan langur (trachypithecus auratus auratus)

In captivity, langurs (foregut fermenting primates) often suffer from digestive disorders, and in particular display soft stools on diets with a high proportion of fruits, vegetables, and grain products. In this study, we tested whether the improvement in feces consistency expected after an omission of vegetables from a conventional diet was also accompanied by a change in the excretion pattern as measured by the mean retention time (MRT). Two adult Javan langurs were kept together and offered a conventional diet of pellets, browse, vegetables, or a diet consisting of pellets and browse only. MRT were measured with cobalt-EDTA as the fluid and chromium oxide as the particle marker before, during, and after the test diet, collecting the feces of both animals together. MRTs of fluids and particles were longer (47/49 h) on the test diet as compared to the usual diet (42/43 h). Feces consistency improved during the test period. The test period was marked by an increased fiber intake; however, on the conventional diet, dietary water intake exceeded the calculated water flux for these animals distinctively, due to the high proportion of vegetables. Therefore, it cannot be decided whether the increase of fiber level alone or also a reduction of the excessive water intake was responsible for the changes observed. Comparing the results of this study to other studies on ingesta retention in foregut fermenting primates, no correlation between the body mass of the animals and the MRTs measured is evident, which is in accordance with observations in other groups of foregut fermenters

Effect of diet on the feces quality in javan langur (Trachypithecus auratus auratus)

A high intake of easily fermentable carbohydrates and a low intake of fiber material are generally regarded as major factors affecting the health of captive langurs. The effect on fecal consistency of excluding fruits and vegetables from the diet was evaluated in Javan langurs (Trachypithecus auratus auratus). Cross-over trials were carried out at Rotterdam Zoo and at the Apenheul Zoo, The Netherlands. During the first and third dietary period, the langurs were fed their usual diet, which contained fruits, vegetables, langur pellets, and browse. During the second period, the vegetables and fruits were excluded from the diet and the diet essentially consisted of pellets and browse. Feces consistency was scored using a fecal score chart developed for langurs. During the second feeding period the feces consistency improved significantly in animals at both zoos. Across all trials, a firmer feces consistency was correlated with an increase in dietary cell wall (measured as neutral detergent fiber) and a decrease in dietary water. It is suggested that the combined decrease in the intake of soluble sugars, the increase of fiber intake, and a lower amount of dietary water in the diet resulted in more solid stools. The results indicate that a dietary neutral detergent fiber content of approximately 46% in dry matter will result in a feces consistency indicative of undisturbed gut function

Studies on the mechanism by which a high intake of soybean oil depresses the apparent digestibility of fibre in horses

An increased intake of soybean oil at the expense of an iso-energetic amount of non-structural carbohydrates reduces the apparent digestibility of fibre in horses. Literature data indicate that bile acids and linoleic acid (C18:2 n ¿ 6) may inhibit growth of pure cultures of microorganisms. In the present series of experiments, the hypotheses tested were that after extra fat intake as soybean oil more bile acids and linoleic acid would enter the caecum which depresses microbial growth and thus also fibre fermentation. Based on measurements of faecal bile acid excretion in horses, no evidence was obtained for a higher influx of bile acids into the caecum after iso-energetic substitution of dietary soybean oil for starch plus glucose. When dietary palm oil was replaced by soybean oil, which caused a six-fold increase in linoleic acid intake, fibre digestibility in horses was not lowered. The infusion of linoleic acid into the caecum of fistulated ponies increased apparent fibre digestibility. It is concluded that the results of the three experiments disprove the hypotheses tested