Research Results - (PDF, 101 mb) - USAID

ity was measured by total fecal collection on
four animals per treatment during the 16th week
of the trial. Carcass data was collected after
slaughter at the end of the trial.
Intake and daily gain were significantly
higher (P < .05) for animals fed diet C: respective
values for A, B,C, and D were 101, 99,109,
and 103 g DM/kg BW' 7/day; 184,187,209, and
190 g/day. However, diet had no effec .7'> .05)
on feed efficiency (8.2 to 8.5 kg DM/kg gain)
and carcass yield (54.4 to 54.9%). Increasing
dietary CP level improved (P < .05) CP digestibility
regardless of source of nitrogen (53, 61,
64, and 64%, respectively, for A, B,C, and D).
On the other hand digestibilities of total organic
matter (61 to 64%) and NDF (39 to 42%) were
not significantly affected.
These results show that increasing CP
level from 12 to 16% in diets containing carob
pulp does not necessarily improve lamb performance
unless urea is included in the diet. Urea
feeding increases the level of ammonia in the
rumen and this may overcome the inhibition of
proteolysis caused by tannins present in carob
pulp. Therefore it appears to be nutritionally
and economically beneficial to use urea as part
of the supplementary nitrogen in diets containing
carob pulp for fattening lambs.
Ammoniation Versus Urea or Natural Protein
as Nitrogen Supplements of Citrus Pulp Based
Diets for Sheep
This study was conducted to evaluate
ammoniation of citrus pulp as a method of
nitrogen enrichment of diets containing this byproduct.
Citrus pulp was either evaluated with
ammonium hydroxide (T),supplEmented with
urea (T2), ammoniated with urea (T3), or
supplemented with horse beans (T4). Citrus
pulp was incorporated at a level of 45% in all
four diets. A low nitrogen grass hay (6% CP)
was used as the forage component in these diets
which also contained 10% molasses and 2%
mineral mix and were isonitrogenous (11% CP).
Ammoniation of citrus pulp was carried out
with a procedure similar to that usually used for
straw or crop residues with the following
parameters: 5% urea or 2.8% NH3 on DM basis,
30% moisture, and eight-week reaction time.
Thirty-two Sardi lambs (six months old
and averaging 18 kg BW) were used. Four
balanced groups of eight animals were randomly
assigned to one of the four diets. The
trial lasted 105 days during which individual
feed intake was measured. Growth was monitored
and carcass data collected after slaughter.
In vivo digestibility and nitrogen balance were
also measured during a seven-day period on
four animals for each group.
This trial has not yet been completely
summarized. Preliminary data show that
ammoaiated citrus pulp resulted in somewhat
lower gains (157 and 143 g/day for Ti and T3,
respectively) than urea (173 g/day) or horse
bean (189 g/day) supplemented citrus pulp.
Intake on diet T4 tended to be lower (96, 99, 93,
and 89 g DM/kg BW./day for Ti, T2, T3, and
T4, respectively). This resulted in T4 having the
best feed efficiency (6.3 kg DM/kg gain); valuL,
for T1, T2, and T3 were 7.8, 7.4, and 8.7 kg DM1
kg gain, respectively. Carcass yield varied
between 49 and 51% and was not significantly
affected by dietary treatments.
In terms of digestibility, the lowest
values were obtained with T1 and the highest
with T4; respective values for T1, T2, T3, and T4
were 60.4, 65.4, 63.9, and 71.2% for DM; 49.2,
58.3, 56.6, and 62.6% for CP; and 60.8, 66.4, 64.4,
and 72.3% for energy. It can be concluded that
ammoniation of citrus pulp may not have any
advantage over simple urea addition to the diet.
Lamb growth performance obtained with nonprotein
nitrogen supplementation in the form of
urea was comparable to that obtained with
horse beans, which are a much more expensive
source of nitrogen. However, animals fed diets
containing horse beans required less feed per
unit of gain than animals fed the others diets.
When making practical recommendations these
economical aspects should be taken into consideration.
c. Supplementation of Wheat Straw Diets
Protein and Energy Supplementation of Wheat
Straw Diets for Pregnant Ewes
Forty-eight ewes were used to determine
the effects of protein and energy intake during
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