Highlights in Bioscience;


Highlights in BioScience
ISSN: 2682-4043
DOI:10.36462/H.BioSci.20214

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Research Article

Open Access

1 Department of Animal Science, Cross River
University of Technology, Faculty of
Agriculture and Forestry Obubra Campus,
Cross River State, Nigeria.

2 Department of forestry and Wildlife, Kogi
State University, Anyigba, Nigeria

Contacts of Authors

* To whom correspondence should be
addressed: Peter. Noah Gboshe

Citation: Gboshe PN and Osarenakhue ES
(2020). The effect of concentrated feed
supplementation regimes on the nutrients
digestibility of grasscutters (Thryonomys
swinderianus) fed Pennisetum purpureum as
basal Feed. Highlights in BioScience Volume
3. Article ID 20214. dio:10.36462/
H.BioSci.20214

Received: May 26, 2020

Accepted: July 30, 2020

Published: August 13, 2020

Copyright: © 2020 Gboshe and Osarenakhue.
This is an open access article distributed under
the terms of the Creative Commons Attribution
License, which permits unrestricted use,
distribution, and reproduction in any medium,
provided the original author and source are
credited.

Data Availability Statement: All relevant data
are within the paper and supplementary
materials

Funding: The authors have no support or
funding to report.

Competing interests: The authors declare that
they have no competing interests.

The effect of concentrated feed supplementation regimes
on the nutrients digestibility of grasscutters (Thryonomys
swinderianus) fed Pennisetum purpureum as basal feed.

Peter. Noah Gboshe1* and Ebiloma Stella Osarenakhue2

Abstract
The study was designed to determine the effect of concentrated feed

regimes on nutrients digestibility of grasscutters (Thryonomys
swinderianus) fed Pennisetum purpureum as basal feed. A total of fifty
grower grasscutters were randomly assigned to 5 treatment groups of 10
grasscutters each with 5 replicates, two animals serving as a replicate.
Treatment was 1, 2, 3, 4, and 5 for 1, 3, 5, 7, and 9%, respectively, of
concentrated feed served at their weekly live weight. Parameters measured
included apparent coefficient of digestibility and percentage digestible
nutrients. The results obtained showed that the coefficient of digestibility
showed a significant difference in all the nutrients evaluated. Percentage
digestible nutrients and total digestible nutrients were also significantly
affected. The high coefficient of digestibility of the various nutrients and
total digestible nutrients are indications that adequate nutrients were
available for growth and maintenance of the grasscutters. The findings of
this study suggested that supplementation of forage with formulated
concentrate can be an aid in the digestion of nutrients by grasscutters for
their growth performance while in captivity. The digestibility of nutrients
when concentrate supplement and elephant grass were combined,
particularly 5% concentrate supplement was not affected. Based on the
results, it was, therefore, recommended that it should be used in improving
the growth performance of grasscutters.

Keywords: Concentrate, supplementation regimes, nutrient digestibility,
Grasscutters, Pennisetum purpureum.

Introduction
Animal protein production in Nigeria from domestic livestock has been

steadily falling by approximately 1.4% annually, while the human population has
been increasing at an annual rate of 3.3% [1]. So, indeed, there is need to attempt
to bridge the animal protein gap for Nigerians to attain the FAO recommended
daily animal protein intake that is deficient in the diets of an average Nigerian and
also try reducing the under-five death that is usually experienced as a result of
malnutrition. This can be achieved by the provision of animal protein knowing its
functions in the health status in the human body [2,3]. Unfortunately,
conventional and regular sources of animal protein supply in the country Such as
beef, pork, goat meat and poultry are getting out of the reach of the common
populace due to economic down-turn. In an attempt to reduce this situation
therefore, we must think of animals from the wild with acceptable potentials and
one of such animals is grasscutter (Thryonomys swinderianus), a micro- livestock.
Mbah [4] have suggested that an area where effort may be rewarded in terms of
meeting the animal protein requirement of Nigerians is the contribution of wild
animal.

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He added that, the shortage of animal protein in the
third world countries can be ameliorated by improving the
existing conservation programme of wildlife particularly the
conservation and domestication of rodents that are tractable,
prolific and widely accepted to the public for consumption.
Again, that, captive rearing of rodents and other species of
manageable sizes in cages and enclosures might augment the
bush meat supply from the wild which can lead to a reduction
of hunting pressure on the wild game and rodent grasscutter
could be the rodent of choice. It was observed a gradual shift
from the production and consumption of conventional animal
protein sources (cattle, sheep, swine, goat, poultry) to a class
of livestock referred to as ‘mini-livestock’, ‘micro-
‘unconventional livestock’ [5].

With the shortage of animal protein, nutritionists are
now interested in prolific, good converters of feed to flesh
and short production cycle animals [6]. The grasscutter meat
is favourite and it accounts for the greater proportion of bush
meat sold in most part of the continent of Africa particularly
West Africa [7]. The major problem in the production of
monogastric animals, such as poultry and pigs, emanates
from the high costs of ingredients such as cereal grains and
soybeans, which form 50-80% of formulated feeds [8]. Their
high cost emanates from the fact that, they feature
prominently in human diets in the developing world but
grasscutters do not belong solely in that group. Akinloye, [9]
and Opara and Fagbemi [10] reported that, proper feeding is
the major factor that determines the health of any animal that
captive reared grasscutters are fed with both forages and
concentrates but the proportion of concentrate must be in low
quantity to avoid digestive problems hence the need to search
for a concentrate-feeding regime that can improve the
performance of grasscutters. Diseases are not very common
problem in grasscutters [11]. They added that, the severity of
these diseases is influenced by the nutritional status of the
animals, especially in the dry season when feed is inadequate
in quantity. Backyard rearing of grasscutter in rural or urban
settlement has the capacity to provide adequate animal
protein of an average family year round [12].

In addition, its management requirements are low-cost.
It feeds on a wide range of feedstuffs, such as grasses,
legumes, to tuber crops Such as sweet potatoes and cassava
and other industrial by-products [12]. Asibey [13] earlier
reported that grasscutter meat has a protein content of 24.7%,
and a low fat content of 1.2% makes it better than beef with a
protein content of 19.6% and fat content of 6.6% and pork
with a protein content of 19.4% and fat content of 13.4%.
The grasscutter’s gastro-intestinal tract is adapted to handle
high fibre materials because of the presence of a large
caecum which houses some microbes that help in the
digestion of cellulose. The presence of cellulolytic bacteria in
the caecum of the grasscutter has been shown by [14].
Animals with this system are referred to as hind-gut
fermenters, meaning that feed is broken down by bacteria at
the end of the digestive system. The microbial activity of the

caecum is of great importance for the processes of digestion
and nutrient utilization from fibrous material [15].

Grasscutter exhibit some features of the ruminant by
consuming large quantities of forages (leaves and stems) and
fermenting it in the gut chamber that harbours microbes and
B-vitamins are useful by-product of the process. The
difference is that whereas, for the ruminants the rumen is at
the beginning of the gut and the products of fermentation are
absorbed from the rumen and lower gut, the caecum is
towards the end of the gut, and the grasscutter has to re-ingest
fermentation products through the mouth, that is, they also
practice caecotrophy Such as the rabbit. The fermentation of
fibre in the guts of herbivorous results in the production of
volatile fatty acids (VFAs) [16] which is absorbed across the
epithelial membrane. VFAs account for much of the
metabolizable energy supply to the animals [17]. KariKari
and Nyemeasem [18] reported that increase in the dietary
components of crude fibre (CF) acid detergent fibre (ADF)
and neutral detergent fibre (NDF) decreased digestibility and
daily weight gain in grasscutters. In another study with
grasscutters, Van zyl et al [19] found that high dietary fibre
reduced the digestibility of dry matter, protein and fat while
the digestibility of fibre component (NDF, ADF and
hemicellulose and cellulose) was comparable to that of
grasscutters on the low fibre diet. Elephant grass is rather low
in energy and protein, due to its high cell wall content [20].
Elephant grass is very sensitive to climatic conditions,
maturity and regrowth days, with a decrease in crude protein
content, an increase in fibre, a decrease in dry matter and cell
wall, as measured by in situ degradability and in vivo
digestibility [21, 22, 23].

Since at the moment, no baseline nutrient
requirements and no particular feeding regime for
concentrate have been established that can aid for nutrients
digestion for optimal performance. Therefore, the objective
of this research was to evaluate the concentrate-feeding
regime on the nutrients digestibility of grasscutters using
Elephant grass as basal feed.

Materials and Methods

Experimental Location

The study was carried out in Obubra, Cross River State,
Nigeria. This is located between longitude 80-90 E and
Latitude 60-70 N of the equator. The mean annual rainfall of
the area ranges from 500 to 1070 mm with warm weather and
ambient temperature of about 200c-300c [24]. Obubra is
located along the banks of the Cross River in the Southern
Guinea Agro-Ecological Zone of Nigeria. Obubra is about
159 km from Calabar, the State Capital of Cross River State
of Nigeria.

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Experimental Animals and Design
A total of fifty weaned grasscutters between the ages of

3-4 months obtained from a local farmer in Ibadan were used
for the digestibility trial. The grasscutters were put into
groups of similar body weights and were randomly assigned
to five treatments feeding regimes in a completely
randomized design. The grasscutters were randomly
assigned to 5 treatment groups of 10 grasscutters each with 5
replicates with two animals serving as a replicate. The
animals were given elephant grass as basal feed ad libitum
and formulated concentrate supplemented at a feeding
regime of 1, 3, 5, 7, and 9% for T1, T2, T3, T4 and T5

respectively of their weekly live body weight throughout the
period of the experiment.

Housing and Experimental procedure
The grasscutters were individually housed in clearly

and properly-labelled concrete cells measuring 90 x 75 x 40
cm (length x width x height). There was an opening only at
the top in order to eliminate cross-ventilation and prevent the
adverse effect of cold because grasscutters are highly
susceptible to pneumonia. The top was partly covered to
create a darken area meant for hiding which is their habit.
Each cell was provided with a feeder and a drinker. The
cemented cells were constructed in a well-ventilated cement
block walled house roofed with asbestos sheets to protect the
animals from bad environmental conditions such as rainfall
and cold conditions.

On the introduction into the cells, the animals were
provided with antistress agents in drinking water. They were
also dewormed and given a dosage of 5 gm each of
coccidiostat. Elephant grass (Pennisetum purpureum), were
cut and allowed to wilt for about 12 hours, weighed and fed
daily as a basal diet. Water and elephant grass were supplied
ad libitum. The animals were weighed weekly throughout the
period of 20 weeks of the study. All cells were cleaned daily
in order to ensure an adequate level of sanitation.

Experimental diet
A concentrate supplement diet was formulated to

contain approximately 18% crude protein and a
metabolizable energy of 2961.47 kcal/kg (Table 1) which
was used at different feeding regimes of 1, 3, 5, 7 and 9% of
their weekly body live weight and fed with wilted Elephant
grass as basal feed.

Chemical Assay
The grasses were harvested around the study area

wilted for about 18 hours chopped to pieces, milled and
analysed for Proximate chemical composition (to include
gross energy) according to the procedure outlined by [25]
while the fibre obtained was characterized to its component
fractions according to the procedures outlined by [26].

Digestibility trial
At the end of the feeding trial, one grasscutter per replicate
with the live weight approximately their treatment average
live weight, were selected and used for the digestibility trial.
Faecal collection lasted for seven (7) days, during this period
the grasscutters were fed about 75% of weight of their feed
intake per day since the level of feed intake increases the rate
of passage of the digest from the GIT and thus reduces the
digestibility of nutrients [27]. Faecal collections were obtain
after sorting out other contaminants. Before the
commencement of faecal collection the grasscutters were
deprived of feed for 18 hours to ensure that the faecal
collection corresponded to the feed offered. The fresh faeces
from each replicate were weighed and oven-dried at 800c for
24 hours, the oven-dried faeces per replicate were bulked,
thoroughly mixed together and milled. Samples of the
ground faeces were stored in airtight sample bottled properly
labelled and taken for chemical analysis.

Table 1. Composition of concentrate feed and calculated
values of experimental diets
Ingredients %
Maize 58.41
Soybean meal 27.59
Rice offal 10
Bone meal 3
Vitamin-min-premix* 0.5
Common salt 0.5
Total 100
Calculated nutrients composition.
Crude Protein 18
Metabolizable Energy (/kcal/kg) 2961.47
Crude fibre (%) 6.97
Calcium (%) 1.16
Phosphorus (%) 0.89

* Each 1 kg of vitamin/mineral premix manufactured by BEAUTS Co. Inc.
Man, U.S.A., contains Vitamin A 220,000, Vitamin D 66,000, Vitamin E 44,
014; Vitamin K 88 mg; Vitamin B 12; 0.76 mg; Niacin 1122 mg, Calcium
27%, Phosphorus 10%, Iron 0.6%, Zinc 0.35%, manganese 0.25%, Copper
0.06%; Iodine 0.002%, Cobalt 26 ppm, Selenium 4 pp. ME = Metabolizable
Energy.

Statistical analysis
Data collected were subjected to analysis of variance

(ANOVA) using MINI-TAB version 16.0 [28], where means
were significant, there were separated at 5% significant level
of probability using the least significant difference according
to the procedures contained in the software.

Results and Discussion

Proximate composition of the concentrate feed
supplement and Elephant grass

The result of the proximate composition of the
formulated diet and elephant grass used for the study are
presented in Table 2. The crude protein content of the
experimental diet analysed (17.8%) was similar to the

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calculated value (18%) and met the crude protein
requirements of growing grasscutters (18%) [29]. Elephant
grass has low protein content of 8.18%, high fibre content of
27.19% and ether extract content of 1.18%, thus
necessitating the use of formulated concentrate which may be
suitable to satisfy the nutrient requirements of a growing
grasscutter especially when supplemented with concentrate
[9, 10]. The results of proximate analysis is similar to that of
Onyeanusi et al. [30] and Wogar et al [31] with some
variations may be due to soil nutrients or period of harvest
since these factors among others are known to affect the
nutrients availability of forages.

Characterization of the crude fibre content of
Elephant grass

The characterization of the crude fibre content of
elephant grass presented in Table 3 showed that, it contained
39.91% cellulose, 20.82% Hemicellulose, 66.95% neutral
detergent fibre (NDF), 41.91% acid detergent fibre (ADF)
and 35.10% acid detergent lignin (ADL). Characterization of
the crude fibre of the elephant grass showed that, cellulose
content of 39.9% recorded in this study was slightly different
from 45.60% reported by [32] but this fell within the range of
35-48% reported by [33, 34]. The hemicellulose content of
20.82% was similar to 20.78% reported by Ogunjobi, et al.
[35]. The neutral detergent fibre (NDF) of 66.95% fell within
the minimum and maximum range of 54.1-79.9% reported by
Egbunogie and Bamikole [33], Mohammed et al [34] but
slightly higher than 63.65% reported by Ogunjobi et al [35].
The acid detergent fibre (ADF) of 41.91% was similar to
40.5% reported by (Tangendjaja et al. [32] and also fell
within the range 29.5-52.9% reported by Egbunuogie and
Bamikole [33], Islam et al [34]. The acid detergent lignin
(ADL) of 35.10% corresponds to 35% reported by Ogunjobi
et al. [35] but differed from the value range of 27-59%
reported by Egbunuogie and Bamikole [33, Mohammed et al.
[34]. These variations in the fibre characterization in this
study and these authors may be due to the season or age of
harvest of the elephant grass. It is known that lignification of
forages depends on the seasons and particularly the age
because the cell wall gets more lignified as the plant matures
[36].

Apparent coefficient of digestibility of grasscutter fed
Elephant grass with different levels of concentrate
supplement regimes

The nutrient digestibility of grasscutter fed elephant
grass with different levels of concentrate supplement regimes
is shown in Table 3. The high coefficient of digestibility of
crude protein of the diets in this study (68.53 to 82.94%) is an
indication that dietary fibre levels of 5% and 31%
concentrate and elephant grass, respectively, did not
adversely affect the digestibility of crude protein. The crude
fibre levels present in this study did not impair the utilization
of other nutrients, especially crude protein. This animal being
a pseudo-ruminant was able to handle the fibre content of the
elephant grass. It is known that, fibre in the diet of
monogastric impair the utilization of other nutrients,
especially crude protein utilization [37].

Table 3. Characterization of the crude fibre fractions of
Elephant grass (Pennisetum purpureum).
Constituents Proportion (%)
Neutral Detergent Fibre (NDF) 66.95
Cellulose 39.91
Hemicellulose 20.82
Acid Detergent Fibre (ADF) 41.91
Acid Detergent Lignin (ADL) 35.1

Elephant grass have acid detergent fibre ADF content
of (35.10%) and thus, elephant grass dietary crude fibre may
not reduce digestibility of CF and other nutrients in
grasscutter since this species of animal digestive system has
been adapted to this type of grass with this CF level in the
wild. This explains why the crude protein digestibility was
very high in T1 in attempt to meet their nutrient requirements
since the nutrients were low in grasses. Adegbola and
Okonkwo [38] reported that there is a negative correlation
coefficient between crude fibre and nutrients digestibility, an
indication that high crude fibre in the diet depresses nutrient
digestibility. The levels of fibre inclusion in this study may
be within the acceptable range for grasscutter, thus the
digestibility of crude protein was high.

Table 2: Proximate composition of elephant grass and concentrate supplement.

The high and comparable coefficient of digestibility of
crude fibre in all the feeding regime treatments (67.46 to
85.95%) may indicate that the elephant grass dietary fibre
contains more digestible carbohydrates than indigestible.
The acid detergent lignin present in elephant grass fibre is
35.10% and may be low enough to be handled by grasscutters.
The digestibility of crude fibre has earlier been shown to be

modified by the degree of lignification of the dietary fibre
rather than the fibre level, and this shows differences in feed
consumption [39]. The high coefficient of digestibility of
non-lignified materials has been previously reported
Adegbola and Okonkwo [38]. Fibres from different sources
could vary in digestibility depending on the proportions of
cellulose, hemicelluloses and lignin. Karikari and

Constituents Dry matter Crude protein Crude fibre Ether extract Ash NFE ME/kcal/kg

Elephant grass % composition 34.3 9.25 31 1.17 9.28 49.3 2187.17
Concentrate % composition 86.98 17.85 5.07 3.2 10.12 50.74 2720.92

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Nyameasem [18] reported that concentrate of high neutral
detergent fibre (NDF) (55%) content may not be able to
support rapid growth of captive reared grasscutters. They
added that increase in the dietary component of crude fibre,
acid detergent fibre (ADF) and NDF decreases digestibility
and daily gain in grasscutters. In another study with
grasscutters, Van zyl et al. [19] reported that high dietary
fibre reduced the digestibility of dry matter, protein and fat
while digestibility of fibre component, NDF, ADF,
hemicelluloses and cellulose was comparable to that of
grasscutters on a low fibre diet.

The coefficient of digestibility of crude fat, (27.65 to
72.69%) observed in this study is similar to the value 64.40%
reported by Ogunjobi et al. [35]. The high coefficient of
digestibility of fat in T1 by the grasscutters in this study can
be attributed to the acceptable range of crude fibre in that
treatment which did not contain high amount of lignin even
though they ate more forage, thus nutrients utilization and
availability at the tissue level were not depressed, it was just
the quantity of nutrients in the diet that may not be sufficient.
The coefficient of digestibility of ash in this study ranged
from 65.01 to 84.47% which was highest at T1 but similar at
T5, T7 and T9. The concentrate supplement was formulated to
supply balanced nutrients to the growing grasscutters.

The coefficient of digestibility of ash can be attributed
to increase in retention time of the food in the caecum since it
was given alongside with elephant grass increased the
availability of nutrients by increasing the period of exposure
of food to the digestive enzymes and absorptive surfaces,
thus, increasing digestibility and absorption of nutrients.
Underwood [40] had earlier on reported that, diets with
adequate mineral supplementation seldom vary in their ash
digestibility. The nitrogen-free extract (NFE) in the
experimental feeding regime diets which represents the
readily available carbohydrates recorded a relatively low

coefficient of digestibility of 25.10 to 56.41%. However, this
implies that, this concentrate feeding regime and elephant
grass as basal feed can be reported not to have relatively
adverse effect on the readily available carbohydrate, since
the coefficient of digestibility of NFE of the treatments were
within the range of at least (50.02%). The dry matter
coefficient of digestibility, which varied from 75.65 to
82.05% was high and more that 66 to 68% Obi et al. [41]
when they carried out a study to evaluate the nutritive
potentials of four conventional forages fed to growing
grasscutters. The high coefficient of digestibility of dry
matter of the grasscutters in this study probably means that
crude fibre level in the experimental diet did not induce
excessive production of mucin. Excessive mucin increases
the viscosity of the digesta within the gastro intestinal tract
which adversely affects the digestibility of dry matter (DM)
[42]. In the absence of this adverse effect of high fibrous
diets, the digestibility of dry matter increases.

The negative correlation coefficient between crude
fibre and dry matter digestibility values reported by
Adegbola and Okonkwo [38] did not apply, which implies
that the crude fibre levels in the diet may be within the
acceptable and tolerable range for the grasscutters. It was
observed that, digestible energy which represents the
proportion of gross energy which does not appear in the
faeces was found to be very high across the treatments (91.82
to 95.38 kcal/kg). The proximate analysis of concentrate
supplement and elephant grass presented in Table 4 reveals
that the concentrate supplement and elephant grass have fibre
ratio of (5.07:31.00%) respectively that can be handled by
grasscutters being pseudo-ruminant with large caecum that
occupies about 40% of the abdominal cavity [43]. Crude
fibre is feed diluents and reduces the caloric content
(Digestible energy) of feed, but that was not the case in this
study as seen by this very high digestibility of energy.

Table 4. Mean apparent coefficient of digestibility of grasscutter fed elephant grass with different concentrate feeding regimes.

a, b, c, and d means within rows with similar superscripts are not significantly different (p>0.05), SEM= Standard error of mean, NFE =
Nitrogen-free extractives.

Effects of concentrate supplement regimes on percentage
digestible nutrients and total digestible nutrients (TDN)
of grasscutter

The effect of concentrate supplement regimes on
percentage digestible nutrients and total digestible nutrients
(TDN) of grasscutters is presented in Table 5. The feeding
regimes affected significantly (P<0.05) all digestible

nutrients evaluated in this study. It was observed that
digestible crude protein (DCP) of T5 T7 and T9 were similar
(P>0.05) while T3, T5 and T7 did not also differ (p>0.05) but
differed with that of T1. However, these significant
differences cannot be linked to the different feeding regimes
since a particular sequence was not followed. The digestible
crude fibre (DCF) also followed the same sequence of

Nutrients T1 T3 T5 T7 T9 SEM
Dry matter (%) 82.05a 75.65b 68.92c 69.77c 67.46c 1.68
Crude protein (%) 82.94a 77.52a 68.09b 70.66b 66.53b 1.92
Crude fibre (%) 85.95a 74.84b 70.51bc 75.05b 67.46c 1.62
Ether extract (%) 72.69a 53.59b 35.16cd 41.94c 27.65d 3.13
Ash (%) 84.47a 77.23b 65.01d 71.66c 67.05cd 1.54
Nitrogen-free extractive (%) 56.41a 43.01b 29.80c 28.37c 25.10c 3.95
Energy 95.38a 94.09b 91.82c 91.82c 93.10b 0.41

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significant Such as the (DCP) which may suggest that the
crude fibre was at the tolerable level that nutrients could be
digestible by grasscutters as seen in the digestible crude
protein level. The digestible ether extract (DEE) was also
observed to be significant but no particular sequence was
followed. The digestible nitrogen-free extract (DNFE) was
significant (P<0.05). It was also observed that T5, T7 and T9

did not differ significantly (p>0.05).
The total digestible nutrient (TDN) is a figure used to

indicate the relative energy value of a feed to an animal. It is
influenced by the percentage dry matter since water doses do
not contribute to the energy value of feeds. The dry matter of
feed has to be digestible for feed to have a TDN value [42].
The dry matter digestibility value obtained in this study 75.65
to 82.05% is higher than values by Obi et al. [41]. An
indication that, the crude fibre content of the diet did not
interfere with nutrients availability at the tissue level and
adequate nutrients were available for growth and
maintenance. The different feeding regimes (1 to 9%) of
concentrate supplement using elephant grass as basal feed
did not adversely affect the digestible nutrients.

The percentage digestible energy (PDE) was observed
to be significantly affected (P<0.05) and the highest value
observed was in T9 though did not differ (P>0.05)
significantly with T5 and T7. The lowest was observed in T1

which suggests that T1 with 1% level of concentrate
supplement was not enough for energy supply for the
experimental group of the grasscutters which reflected in
them having the lowest total weight gains of 667.50g as was
observed in the growth performance.

Conclusion
The findings of this study suggest that supplementation

of forage with formulated concentrate can be an aid in the
digestion of nutrients by grasscutters for their growth
performance while in captivity. The digestibility of nutrients
when concentrate supplement and elephant grass are
combined particularly 5% concentrate supplement were not
affected. It was therefore recommended that, it should be
used in improving the growth performance of grasscutters.

Table 5. Effects of concentrate supplement-feeding regimes on percentage digestible nutrients and total digestible
nutrient (TDN) of grasscutter.

Nutrients T1 T3 T5 T7 T9 SEM
Digestible crude protein 5.14c 5.84b 6.27ab 6.46ab 6.73a 0.22
Digestible crude fibre 7.11b 7.50b 8.88a 9.13a 9.04a 0.29
Digestible ether extract 0.73a 0.64b 0.50c 0.62b 0.44d 0.02
Digestible Nitrogen-free extractive 14.55a 13.19ab 11.64bc 10.76c 10.23c 0.65
Total digestible nutrient 28.44a 27.98ab 27.92b 27.73b 26.99c 0.17
Energy. 1075.60c 1290.70bc 1575.80a 1520.70ab 1716.60a 79.15
a, b, c, and d means within rows with similar superscripts are not significantly different (p>0.05), SEM= Standard error of mean.

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