Loading...
Characterisation of feedstuffs for ruminants.
Moloney, Aidan P Woods, V.B. O'Mara, Frank P.
Moloney, Aidan P
Woods, V.B.
O'Mara, Frank P.
Citations
Altmetric:
Keywords
Date
2001-05-01
Collections
Files
Loading...
eopr-4383.pdf
Adobe PDF, 114.95 KB
Research Projects
Organizational Units
Journal Issue
Citation
Moloney, A.P., Woods, V.B., O'Mara, F.P., Characterisation of feedstuffs for ruminants, End of Project Reports, Teagasc, 2001.
Abstract
A wide variety of feed ingredients are used in the manufacture of
compound feeds in Ireland. Unprocessed feedstuffs vary from batch
to batch due to differences caused by variety, soils, weather, etc. By
-product feeds may also vary due to the processes from which they
were produced. Accurate information on the nutritive value of feeds
is essential for accurate ration formulation. A series of experiments
was carried out to determine various nutritional characteristics of
concentrate ingredients either locally produced or imported into
Ireland. From these experiments it was concluded that :
* The digestibility values of concentrate ingredients derived in
maintenance-fed sheep are applicable to maintenance-fed
cattle.
* Feed is not utilised as efficiently when the level of feeding is
increased from maintenance to 2 x maintenance.
* The improved feed conversion efficiency in steers offered a
restricted allowance of concentrates cannot be attributed to
a difference in digestibility but can be attributed in part to a
lower rate of fat deposition compared to steers offered ad
libitum concentrates.
* The residue after oil extraction from Camelina sativa could
replace some imported protein-rich feedstuffs in ruminant
rations but to fully achieve this potential, the residual oil
content must be decreased.
* For measurement of ruminal degradability of concentrate
ingredients a wide range of forage to concentrate ratios and
feeding levels can be used.
* It is important to consider the actual outflow rate of
nutrients from the rumen when measuring the feed value of
individual concentrate ingredients as this can have an impact
on the effective degradability and the relative nutritive values
assigned to such ingredients.
* Large variations in ruminal degradation occur within and among feeds. The ruminal degradability of different samples
of any one feed should be measured to determine their
true nutritive value for feeding ruminants.
* Within most concentrate ingredients examined, the variation
in small intestinal digestibility (SID) due to source indicates a
range in the quantity of amino acids supplied to the animal
for productive purposes. The more rapid and cost effective
in vitro technique can be used to screen the SID of
concentrate ingredients.
* Target volatile fatty acid (VFA) concentrations and
proportions may be produced by varying the proportions
of the individual ingredients in a concentrate ration.
* An in vitro procedure allowed VFA production to be
measured across a large range of feeds under standardised
conditions.
* On average, 75% of gas produced during ruminal
fermentation consists of carbon dioxide. The variation in
methane production among individual concentrate
ingredients provides an opportunity to formulate rations to
minimize environmental pollution with methane.