Determination of the complex of cell wall substances in plant products

Because of the climatic conditions, the Finnish milk production research has focused to improve the utilisation of grassland, mainly as conserved forages. The main research areas have been ensiling, evaluation of the forage feeding value, predicting nutrient supply from grass silage-based diet and the effects of forage quality and concentrate supplementation on milk production responses. Due to changes in ensiling technologies and variety of forage crops new silage additives have been adopted. A centralized system for the analysis of forage energy value is based on NIRS calibration. It was calibrated against in vitro pepsin-cellulase solubility method that was validated against in vivo digestibility. The concentration of indigestible neutral detergent fibre was found to be a useful parameter both in empirical models predicting forage digestibility and mechanistic rumen models predicting the amounts of absorbed nutrients. Models predicting relative intake potential of forages and total diet were developed, and an intake model combining animal and diet effects independently of each other was developed. Using meta-analysis approaches a nutrient response model was developed for dairy cows for milk, energy corrected milk and protein yield. Feed evaluation, intake and nutrient response models form now the basis of practical Finnish ration formulation system that can optimize diets according to maximum income over feed cost in addition to minimum feed cost.

Section: Silage Composition With Reference To Nutrient Availabilitymentioning

confidence: 99%

An overview of silage research in Finland: from ensiling innovation to advances in dairy cow feeding

Huhtanen¹,

Jaakkola²,

Nousiainen³

2013

“…From the meals and ground rusks determinations were made of dry matter, ash and crude protein. Plant cell wall substances were also determined by the methods of Salo (1965 a) and Paloheimo and Vainio (1965), and Cr 2 0 3 from the rusks (Paloheimo and Paloheimo 1935).…”

Section: Methodsmentioning

confidence: 99%

Comparative digestibility studies with hens and rats

Syrjälä¹

1971

Abstract. Trials were made to compare the digestibility of feeds in hens and rats. In the comparison particular attention was paid to the true digestibility of the feeds. The digestibility of rusks made of wholewheat meal was compared in hens and rats. The rats digested 62.1 % of the cell wall substances of the whole wheat meal, while the value for the hens was 16 %-units lower. The true digestibility of the other N-free organic matter was also clearly lower in the hen trial than in the rat trial. In the rat trials the digestibility of wholewheat meal was compared with that of bark meal. The true digestibility of the organic matter of the bark meal was only 23.6 %, while that of the wholewheat meal was 92.4 %. The digestibility of the cell wall substances of the bark meal was 18.5 % and of the wholewheat meal 62.1 %.It is rather difficult to compare the digestibility of feeds in hens and rats, owing to the great differences in the digestive tract and excreta of these animals. If the comparison is based on the apparent digestibility values, the results can be deceptive. This is due to the fact that the quantity and quality of the endogenous and bacterial materials of faeces vary considerably in the different animal species, and also in the same species when different rations are given. With poultry the uric acid of the excreta also leads to inaccurate digestibility results, if these are based only on the apparent digestibility. If the efficiency of digestion in different animal species is to be compared, the true digestibility of the feeds of these animals has to be known. The same applies if widely differing feeds are given to the same animal species (Syrjälä 1967). In this paper the word faeces means also the excreta of the hens.The purpose of this study was to investigate and compare the efficiency of digestion in hens and rats by estimating the true digestibility of their feeds. The feeds used in the digestibility trials were wholewheat meal and bark meal. The latter is made from the inner bark of pine. Experimental procedureFeeds. The digestibility of wholewheat meal was studied in hens and rats; the digestibility of bark meal only in rats.

“…In the studies carried out by Rubner (1916aRubner ( , 1916Rubner ( b, 1919 at the beginning of this century, on the other hand, results approximating rather closely the total amounts of cell-wall material were achieved, the methods are very complex for routine work, however. The procedure of Paloheimo and Vainio (1965), requiring differentcorrection determinations, is also laborious, even though it gives a rather accurate determination of the complex of cell-wall substances in animal foods.…”

mentioning

confidence: 99%

Approximate determination of the cell-wall complex of vegetables by enzymatic digestion

Salo

Kotilainen

1967

The paper describes the results of experiments in which 12 different vegetables were treated with pepsin, trypsin or trypsin + diastase in buffer solutions. The effects of certain variations in the methods on the final results are also discussed. The purpose of the study was to find out whether it would be possible to develop a simple procedure that would yield a residue roughly corresponding to the cell-wall complex in readily soluble plant materials such as vegetables. However, such great differences were found in the solubility of hemicellulose and protein among the different materials that good results cannot be achieved by a uniform method, at least not without many correction determinations.