Selecting for nutritive value in Digitaria milanjiana. 3. Relation of chemical composition and morphological and anatomical characteristics to the difference in digestibility of divergently selected full sibs, and comparison with D. eriantha ssp. pentzii

1991 ◽  
Vol 31 (5) ◽  
pp. 631 ◽  
Author(s):  
Y Masaoka ◽  
JR Wilson ◽  
JB Hacker

Comparisons were made of the dry matter digestibility (DMD) and yield of plant fractions harvested from long-established swards of 6 genotypes of Digitaria milanjiana selected from 3 F1 families for high and low leaf digestibility, and D. eriantha ssp. pentzii (pangola grass). Defined leaf blade, sheath and stem internode fractions were collected at different sward development stages and analysed for DMD, chemical composition, and tissue morphological and anatomical characteristics. The leaf blade of each high-digestibility genotype was consistently superior (1.9-4.5 percentage units) in DMD to that of its low digestibility counterpart, and to pangola grass, at both vegetative and reproductive -- stages. For leaf sheath and stem, the superiority in DMD of the high digestibility group was not evident or was less pronounced. The high DMD selections had green leaf dry matter yields comparable to those of the low DMD group but higher than those of pangola grass. The gain in DMD for leaf blade of the high over the low digestibility selection was consistently correlated with a decrease in cell wall content, acid detergent fibre or lignin, and poorly correlated with other chemical and leaf morphological characteristics. High and low DMD genotypes did not differ in the proportion of cell types in leaf or stem, or in other measured anatomical characteristics.


2020 ◽  
Vol 42 ◽  
pp. e53064
Author(s):  
Fábio Nunes Lista ◽  
João Virgínio Emerenciano Neto ◽  
João Carlos de Carvalho Almeida ◽  
Bruno Borges Deminicis ◽  
David Ramos da Rocha ◽  
...  

The research submitted samples from stems and leaf blades from tree genotypes of Pennisetum purpureum called 93-32-02, 92-70-02, and 91-06-02 (EMBRAPA - Dairy cattle) and elephant grass cv. Napier (reference cultivar) to the chemical, anatomical evaluations, and in vitro dry matter digestibility (IVDMD) measurement. The anatomical characteristics of the stems and leaf blades, the chemical composition, and the IVDMD of these genotypes at 70 days of re-growth were correlated. Concerning IVDMD, the data highlighted differences, and the cultivar Napier presented the smallest value. Digital images obtained by light microscopy from cross-section reveal that all the stem and leaf blade have similar structural organization. Quantitative differences were verified mainly in the stem. The leaves displayed differences only in the mesophyll thickness. The genotypes showed higher potential in the rainy season since they had the largest IVDMD when compared to the cultivar Napier.



1986 ◽  
Vol 57 (1) ◽  
pp. 58-64
Author(s):  
Koji TOYOKAWA ◽  
Kei HANZAWA ◽  
Tatsushi INOUE ◽  
Akira SAKAMOTO ◽  
Kaizo TSUBOMATSU


1967 ◽  
Vol 7 (29) ◽  
pp. 540 ◽  
Author(s):  
R Milford

The chemical composition and feeding value of seven tropical legumes and lucerne were determined by pen feeding experiments with sheep. Most of the legumes were harvested during autumn and winter. Lucerne had the highest feeding value and the highest values for the tropical legumes were obtained for Vigna vexillata, Lotononis bainesii, and Desmodium uncinatum. After frosting, the feeding values of Phaseolus lathyroides and Vigna vexillata were reduced but that of Desmodium uncinatum was not changed. This may have been due to a greater loss of leaf by both P. lathyoides and V. vexillata than by D. uncinatum. Frost did not affect Lotononis bainesii and Medicago sativa, and both had a higher feeding value than the legumes affected by frost. The usefulness of crude protein and crude fibre for estimating dry matter digestibility and dry matter intake and the relation between dry matter digestibility and dry matter intake is discussed. The use of dry matter digestibility to express the nutritive value of feed energy in preference to organic matter digestibility, starch equivalents, and total digestible nutrients is also discussed.



1974 ◽  
Vol 82 (3) ◽  
pp. 419-422 ◽  
Author(s):  
M. C. Rees ◽  
D. J. Minson ◽  
F. W. Smith

SUMMARYPangola grass grown with and without sulphur fertilizer was cut as a 7-week regrowth to measure voluntary intake and digestibility by sheep. To determine the extent of a simple sulphur deficiency half the sheep on each feed were supplemented with 0·6 gsulphur daily. Retention time of feed in the reticulo-rumen and proportion of feed digested anterior to the duodenum was also determined.Sulphur fertilizer increased the sulphur content of the pasture from 0·09 to 0·15%, voluntary intake of dry matter from 44·4 to 64·1 g/kg W0·75/day and dry-matter digestibility from 55·2 to 60·2%. Sulphur fertilizer reduced the retention time in the reticulo-rumen by 16% and increased the extent of dry-matter digestion before the duodenum from 13 to 34%.Feeding a sulphur supplement increased dry-matter digestibility of the low sulphur feed to that found with sulphur fertilized pangola grass but only accounted for 63% of the difference in voluntary intake.It was concluded that fertilizer sulphur leads to large increases in both voluntary intake and digestibility of sulphur deficient grass and that the improvement in nutritive value may be more than can be achieved by feeding a sulphur supplement.



2020 ◽  
Vol 41 (6) ◽  
pp. 2733-2746
Author(s):  
Francielly Paludo ◽  
◽  
Kátia Aparecida de Pinho Costa ◽  
Mariana Borges de Castro Dias ◽  
Fábio Adriano Santos e Silva ◽  
...  

The use of silage has been an efficient alternative to feed supply during the shortage of roughage in dry periods, providing quality feed that is widely used in ruminant feeding. Thus, the objective of this study was to evaluate the fermentative characteristics and nutritive value of corn silage with Tamani guinea grass (Panicum maximum BRS cv. Tamani) through chemical composition, in vitro dry matter digestibility and protein fractionation. The experiment was conducted in a completely randomized design with four replications. The treatments consisted of five silages: corn; corn with 10% Tamani guinea grass; corn with 20% Tamani guinea grass; corn with 30% Tamani guinea grass; and corn with 40% Tamani guinea grass, totalling 20 experimental silos. The addition of tamani grass to silages was determined based on fresh matter. For ensiling, corn was harvested with 320 g kg-1 DM (dry matter) and Tamani guinea grass in a 30-day development cycle with 286 g kg-1 DM. After 50 days of silage, the silos were opened to analyse the fermentative characteristics, chemical composition and protein fractionation of the silage. The results showed that the addition of Tamani guinea grass in corn silage increased the pH and buffering capacity and reduced the dry matter and lactic acid concentration but did not compromise the fermentative characteristics of silages. The addition of 40% Tamani guinea grass in corn silage provided increased levels of crude protein, in vitro dry matter digestibility, protein A, B1 and C, and decreased the fractions B3 and C, which makes Tamani guinea grass an alternative to improve the quality of exclusive corn silage, resulting in better quality silage.



1969 ◽  
Vol 9 (37) ◽  
pp. 192 ◽  
Author(s):  
MJ Playne

Sheep were fed either Townsville lucerne (Stylosanthes humilis) or spear grass (Heteropogon contortus) with and without dicalcium phosphate for an 11-week period. Voluntary intake, dry matter digestibility and liveweight changes of the animals were measured. Sheep fed Townsville lucerne gained body weight whereas those fed spear grass lost weight. Added dicalcium phosphate (4.5 g/day) increased dry matter intake and liveweight gain of the sheep fed Townsville lucerne, but not the digestion coefficient. Sheep consuming spear grass did not respond in any way to the supplement. All sheep fed spear grass received urea daily (2.9g N/day) as a nitrogen supplement. The difference between the two groups in response to dicalcium phosphate is discussed in terms of the chemical composition of the two feeds.



2015 ◽  
Vol 4 (2) ◽  
pp. 415-422
Author(s):  
Amoka Pius ◽  
Tawose O M

The nutritive value ,voluntary dry matter intake, and the nutrient digestibility of graded levels of Gmelina arborea and cassava peels concentrates in WAD sheep was investigated. Twelve WAD sheep aged 1-2 years old and weighting 14.00± 0.45 kg were used in a complete randomized design. Diets were formulated such that cassava peels was replaced with Gmelina arborea leaf meal at 0, 33.33, 66.67, 100% levels, designated as diets A, B, C, and D respectively. Diet without Gmelina arborea leaf meal was tagged the control diet. The concentrate feed was compounded to contain 16% CP. Diets with 33.33% inclusion level of Gmelina arborea had significantly (P<0.05) higher dry matter intake (DMI) 598.80g day-1, while the lowest DMI 425.00g day-1 was obtained in animals fed 100% inclusion level of Gmelina arborea. Crude protein intake (CPI) of animals fed diets with 33.33% inclusion levels of Gmelina arborea were significantly (P<0.05) highest, followed by 66.67% inclusion level and the least was observed in 0% inclusion level of Gmelina arborea. Dry matter digestibility (DMD) was significantly (P<0.05) different across the dietary treatments, animals placed on diets with 33.33% inclusion level had the highest DMD, followed by animals on diets with 66.67, 100 and 0% inclusion levels. CP digestibility (P<0.05) increased from 33.33% to 100% inclusion levels of Gmelina arborea leaf meal, the lowest CP digestibility was observed at 0% inclusion level. CF digestibility (P<0.05) increased from 33.33% to 100% inclusion levels of Gmelina arborea leaf meal, while the lowest CF digestibility was observed at 0% inclusion level. N intake increased significantly (P<0.05) with increase in the level of Gmelina arborea inclusion from 33.33% to 100%. N retention was significantly (P<0.05) different, diets with 33.33% Gmelina arborea inclusion had the highest value (64.36g day-1) followed by 66.67%, 100% and the least (52.64g day-1) was at 0% inclusion level of Gmelina arborea.  N balance values also followed the same trend. From the results of this study, it can be concluded that the inclusion of Gmelina arborea leaf meal in WAD rams diet was well tolerated without adverse effect on acceptability, intake and nutrient digestibility, and inclusion level of 33.33% is hereby recommended in ruminants diet for optimum performance and productivity.



1973 ◽  
Vol 53 (2) ◽  
pp. 257-263 ◽  
Author(s):  
G. PELLETIER ◽  
E. DONEFER

Three yearling Cheviot × Suffolk ewes and three Columbia wethers were confined in metabolic cages and fed ad libitum fresh and dried marrow-stem kale (Brassica oleracea var. acephala D.C.) harvested in mid- and late October. Chemical analyses of the forages indicated no marked effects on any of the plant constituents due to drying or advancing maturity. Digestibility measurements demonstrated that marrow-stem kale (MSK) was a highly digestible material with an average dry matter digestibility of 78%. The fresh forages had higher (P < 0.05) dry matter and gross energy digestibility values than the dried form. Dry matter digestibility coefficients were higher (P < 0.05) for late October as compared with the earlier harvest. A trend toward higher (P > 0.05) voluntary intake values due to drying maturity was observed with an average relative intake of 80%. The nutritive value index averaged 65, thus indicating a digestible energy intake similar to a high-quality (legume) forage.



1988 ◽  
Vol 47 (1) ◽  
pp. 105-110 ◽  
Author(s):  
P. K. Bhargava ◽  
E. R. Ørskov ◽  
T. K. Walli

AbstractExperiments were made to study the proportion, chemical composition, and rumen degradability of the morphological components of barley straw (Corgi variety) and to study the selection of these components by sheep. The proportions in the harvested straw dry matter (DM) as leaf blade, leaf sheath, stem and chaff were 128, 314, 500 and 58 g/kg DM, respectively. The different components of straw on analysis proved to have very different concentrations of nitrogen and neutral-detergent cellulase digestibility. The leaf blades had the highest and the stems the lowest values. The degradabilities of DM in the components and in the whole straw were determined by measuring DM loss from samples incubated in nylon bags for various periods in the rumen of sheep. Responses were measured using the mathematical model p = a+b (1–e−ct) where p is DM loss, (a+b) potential degradability, c the rate constant of DM loss and t is the time of incubation. DM losses decreased in the order leaf blades > leaf sheath > whole plant > chaff > stems. Leaf blades also had the highest potential degradability and rate of degradation.In another trial, five sheep were offered unchopped barley straw ad libitum. There were five treatment periods in which sheep were allowed to leave uneaten proportionately 0·2, 0·3, 0·4, 0·5 and 0·7 of the straw on offer for assessing the animal's selection of the morphological components of that straw. The amount of leaf blade in the material consumed increased in largely a linear (P < 0·01) fashion with the amount of excess allowance. The proportion of stem eaten varied conversely. The selection of leaf sheath was less apparent. Little stem was consumed until the proportion of leaf blade in the food available decreased below proportionately 0·4. The practical significance of the study is discussed.



1986 ◽  
Vol 66 (2) ◽  
pp. 483-494 ◽  
Author(s):  
R. M. TAIT ◽  
R. M. BEAMES ◽  
J. LITSKY

The digestibility of four types of grain screenings, No. 1 screenings, rapeseed screenings, mixed feed oats and refuse screenings was measured with pigs, rats and sheep. For the pig diets, hammermilled screenings replaced 60% of a complete basal diet, with the exception of the rapeseed screenings, where replacement level was 10% (hammermilled) and 20% (whole). Digestibility values were determined by difference. In the rat diets screenings were incorporated to provide 1.5 g N 100 g−1 dry matter (DM) and the biological value (BV) of the protein was also measured. In the sheep diets, all screenings except rapeseed were provided as the sole dietary component, with the No. 1 feed screenings and the mixed feed oats pelleted without prior grinding and the other screenings ground before pelleting. For rapeseed screenings, incorporation in the sheep diets was at a level of 30%. For No. 1 screenings, apparent digestibility of organic matter (OMD) and nitrogen (ND) for pigs was 82.3 and 83.2%, respectively; BV for rats was 77.4%, while OMD and ND for sheep was 73.9 and 72.7%, respectively. For rapeseed screenings, OMD and ND for pigs for the hammermilled screenings were 46.1 and 50.7%, respectively, and for the whole screenings were 30.3 and 11.5%, respectively. Biological value (rats) was 80.0%, while for sheep OMD and ND it was 63.9 and 77.4%, respectively. For mixed feed oats, OMD and ND for pigs were 63.8 and 82.6%, respectively; BV (rats) was 61.1% and OMD and ND for sheep were 64.2 and 73.4%, respectively. For refuse screenings, OMD and ND for pigs were 63.8 and 65.4%, respectively; BV (rats) was 83.8%, while OMD and ND for sheep were 59.9 and 65.3%, respectively. Number 1 feed screenings are of a high nutritive value and are suitable as a grain for both pigs and sheep. Unprocessed rapeseed screenings are unpalatable for pigs with both dry matter and protein poorly utilized. With sheep, pelleted rapeseed screenings are readily accepted, and the nitrogen is well digested. If mixed feed oats are ground, protein is well digested by both species although dry matter digestibility is low. Refuse screenings appear to be suitable only for ruminant diets. Key words: Grain, wheat, barley, oats, rapeseed, screenings



Sign in / Sign up

Export Citation Format

Share Document