Digestibility trials

Hainan, E.T. (1944) Digestibility trials with poultry. II. The digestibility and metabolizable energy of raw and cooked potatoes, potato flakes, dried potato slices and dried potato shreds. Journal of Agricultural Science 34,139-154. 

Trial 2. A 2 X 2 X 2 factorial design was used. The variables were hemicellulose from Laurel, neutralized or unneutralized and hemicellulose from Ukiah, neutralized or unneutralized, each fed at 15 and 30% of the ration. The rations are shown in Table V. There were four sheep per treatment. The standard procedure for digestibility trials as developed by the informal forage evaluation committee (30) was used. Each animal was fed individually on the ration for approximately three weeks during which time an estimate of the voluntary feed consumption was made and during days 21 to 30, a standard digestibility trial was completed. 

The relatively high dry matter digestion coefficients, Table V, emphasize the fact that tests rations were essentially concentrate except for the inclusions of oyster shell and sawdust. The conventional digestibility trial data and the in vitro data rank the rations in a similar order. No adequate explanation can be given for the low coefficient for the basal by the nylon bag technique. Although the small sample in vivo and the... 

Zuprizal, Larbier M., Chagneau A. M., Lessire, M., 1990. Bioavailability of lysine in rapeseed and soyabean meals determined by digestibility trial in cockerels and chick growth assay.Anim. Feed Sci.Technol., 35,237-246. 

In a digestibility trial, the food under investigation is given to the animal in known amounts and faecal output is measured. More than one animal (typically four) are used, because animals, even of the same species, age and sex, differ slightly in their digestive ability, and because replication allows more opportunity for the detection... 

A digestibility trial was carried out using three sheep to determine the digestibility of hay. During the 10-day faecal collection period, feed intake and faecal output were recorded. Samples of hay and faeces were analysed in the laboratory ... 

Since digestibility trials are laborious and expensive to carry out, numerous attempts have been made to determine the digestibility of foods by reproducing in the laboratory the reactions that take place in the alimentary tract of the animal. Digestion in non-ruminants is not easily simulated in its entirety, but the digestibility of food protein may be determined from its susceptibility to attack in vitro by pepsin and hydrochloric acid. It is also possible to collect digestive tract secretions via cannulae and to use them to digest foods in vitro. 

In a typical digestibility trial, the food under investigation is fed to animals for 21-30 days, with faeces being collected for the last 7-10 days. 

Colorimetry and Spectrophotometry Protein and Amino Acid Analyses Biological Analyses Digestibility Trials Nutrient-Deficient Animals Microbiological Assays Microscopic Analyses for Filth and other Adulterants or Contaminants Physical Methods of Analyses Use of Food Composition Data for Planning Menus and Diets... 

Also see ANALYSIS OF FOODS, section headed "Digestibility Trials.")... 

Nutritional value of byproducts from beet biofuel production evaluated in digestibility trials with sows and sheep... 

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