Diet of the Indochinese silvered langur (Trachypithecus germaini) in Kien Luong Karst area,Kien Giang Province

The Indochinese silvered langur (Trachypithecus germaini) is distributed to the west of Mekong River in Cambodia, Lao PDR, Thailand and Vietnam. During a two‐year study, from May 2014 to May 2016, we collected 320.44 hr of behavior, with 17,040 feeding bouts recorded (142 hr) for T. germaini on Chua Hang Karst Mountain, Kien Luong District, Kien Giang Province, Vietnam. Feeding accounted for 45% of the Indochinese silvered langurs’ activity budget. The plant diet of the Indochinese silvered langurs was principally composed of young leaves (58%), followed by mature leaves (9.5%), fruits (22.7%), flowers (4.7%), buds (3.3%), petioles (1.2%), and other (0.5%). A total of 58 plant species were fed on by the silvered langurs, and leaves of eight species (Phyllathus reticulatus, Ficus rumphii, Ficus tinctoria, Ficus microcarpa, Cayratia trifolia, Streblus ilicifolia, Combretum latifolium, and Streblus asper) were fed on throughout the year. P. reticulatus was most frequently eaten (13.9% feeding time, n = 1,733). Food selection differed significantly between months and seasons. The Indochinese silvered langurs ate 27 plant species in the wet season compared with 23 plant species in the dry season. Leaf chemical composition of two food categories, 16 eaten species (with 10 most frequently consumed species and six least consumed species), and four noneaten species, were analyzed. Feeding samples from eaten species in the Indochinese silvered langurs's diet contained lower amounts of condensed tannin, lignin, protein, ash, and lipids, but a higher amount of total sugar compared with samples from noneaten species. Furthermore, the most frequently consumed species contained lower amounts of lignin compared with the less frequently consumed species. Using a generalized linear model with five variables, including neutral detergent fiber (NDF), total sugar, lignin, lipid, and calcium (Ca) indicated that NDF positively correlated and lignin content negatively correlated with feeding records in the diet of these langur.     

True grit: A microwear experiment

Recently we noted the effects of experimental diets on microscopic dental wear in the American opossum and concluded that it might prove difficult to distinguish the microwear produced by an insectivorous diet from that produced by some kinds of herbivorous ones. We also noted that wear caused by gritty diets and those containing plant opal, although they might be confused with one another, are easily distinguished from other sorts of dietary wear. Our conclusions have been challenged on the basis that possibly we did not allow sufficient time in the experiments for diagnostic wear patterns to emerge. Additional data reported here show that this is not so. Even in our n “control” animals, fed a relatively soft unabrasive diet, enough time elapsed to produce significant dental wear. A new technique is described which for the first time allows the study of changing patterns of microscopic wear in a living animal over a period of time, thus allowing each animal to serve as its own control. A solution containing a broad-spectrum proteolytic enzyme when applied to the teeth of an anesthetized animal removes the proteinaceous coat (pellicle) which will otherwise obscure wear scratches. Precision dental impressions can then be made which reveal the details of the pattern of microwear on the teeth.     

Evaluation of indoxyl-beta-D-glucuronide as a chromogen in media specific for Escherichia coli.

Indoxyl-beta-D-glucuronide (indoxyl) was evaluated as a specific chromogen for detection of Escherichia coli by the membrane filter method. In all, 413 colonies were tested from the indoxyl-supplemented media, yielding 93.3% confirmation, as E. coli. Compared with the indoxyl medium, other media gave either much lower recovery with high verification or equal recovery with poor verification.     

Physical mapping of plasmid and cosmid clones in filamentous fungi by fiber-FISH

Fluorescence in situ hybridization to extended DNA fibers (fiber-FISH) serves as a powerful tool for direct physical mapping in plants and animals. Here, we show that fiber-FISH is useful for contig mapping as well as for estimating the physical distance between genetic markers in fungi. A five-cosmid contig from a chromosome of Nectria haematococca and four cloned genetic markers from a linkage map of Cochliobolus heterostrophus were chosen as models for the application of this technology. In N. haematococca, overlapping and non-overlapping clones were visually mapped on individual DNA fibers, confirming the results from conventional physical mapping perfectly. Fiber-FISH concomitantly indicated the gap size or the extent of overlap between two clones. In C. heterostrophus, the physical distance between the two pairs of genetic markers could be estimated from the microscopic measurements of the intervals. Chromosomal DNA isolated from a pulsed field gel was suitable for preparing the DNA fibers.     

The virus as metabolic engineer

Recent genome-wide screens of host genetic requirements for viral infection have reemphasized the critical role of host metabolism in enabling the production of viral particles. In this review, we highlight the metabolic aspects of viral infection found in these studies, and focus on the opportunities these requirements present for metabolic engineers. In particular, the objectives and approaches that metabolic engineers use are readily comparable to the behaviors exhibited by viruses during infection. As a result, metabolic engineers have a unique perspective that could lead to novel and effective methods to combat viral infection.