BIBLIOGRAPHY AGUSTIN, FERNAN B., April...
BIBLIOGRAPHY
AGUSTIN, FERNAN B., April 2012. Evaluation of Digestibility of Sweet Potato
Meal in Swine. Benguet State University, La Trinidad, Benguet.
Adviser: Marlene B. Atinyao, Ph.D
ABSTRACT
The study was conducted to determine the apparent digestibility of nutrients of
sweet potato meal and commercial feeds supplemented with sweet potato in swine
conducted at Banig, Tawang La Trinidad ,Benguet on February 2012.
A total of nine hogs weighing 85kg per head were distributed using the Completely
Randomized Design (CRD) to the three treatments as follows: commercial feeds, 300g
sweet potato per kilogram of feeds and sweet potato meal.
Analysis showed that sweet potato meal contains 87.46% dry matter, 3.84% ash,
1.29% crude protein, 5.11% crude fat, 5.00% crude fiber, 75.34% nitrogen free extract and
3,383 kcal GE/kg. The digestibility of nutrient in sweet potato meal were as follows:
90.06% for dry matter, 44.76% for ash, 86.01% for crude fat, 96.06% for nitrogen free
extract, and 89.337% for gross energy. The digestibility of nutrients in the commercial
ration were 76.66% for DM, 25.77% for ash, 80.233% for CP, 74.71% for CF, 85.96% for
NFE, 77.270% for GE. The ration that contain commercial feeds and 300g sweet potato
per kg of commercial feed contain 65.41% for DM, 11.75% for ash, 55.763% for CP,
54.42% for CF, 80.03% for NFE, and 65.437% for GE. The digestible nutrient per kg of
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
sweet potato meal was computed as follows: 787.89g dry matter, 17.19g ash, 20.04g crude
fat, 723.73g nitrogen free extract and 3023.667g gross energy.
Statistical analysis showed there are highly significant differences in terms of
digestibility of crude protein, crude fat, gross energy, nitrogen-free extract and the dry
matter and in the digestible nutrient per kilogram of crude protein, crude fat, nitrogen free
extract, dry matter.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
INTRODUCTION
Sweet potato protein is of high nutritive value since it contains reasonable amount
of amino acids. It can provide enough nutrients needed by the animal for maximum
performance. The energy that pigs can get from the sweet potato storage root is similar to
what they get from cassava meal and maize (Quinio, 1986). Although imported corn rather
than sweet potato is widely and very efficiently used as a main carbohydrate source for
pigs diets in our feed industry at the present time, continuous effort have been made to
obtain better utilization of sweet potato as animal feeds. Grown the whole year round, it is
used both food for human and as feed for domestic animals. Sweet potato roots posses
several advantages to the use as a common animal feedstuff, a minimum of culturing
manipulation. But farmer in the Cordillera have limited information in proper processing
of sweet potato for animal feeds. To maximize the use of sweet potato as swine feedstuff,
it is important to know how much of the nutrients sweet potato could be digested by swine.
Knowing the digestibility coefficient of nutrients in sweet potato in swine will
provide a better understanding on how swine utilized sweet potato. It also provides a better
basis for formulating ration using sweet potato meal as feed source. This information could
be used by researcher, animal raisers and students interested in swine production.
The study aimed to determine the utilization of the nutrients in sweet potato meal
through digestibility.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Specifically, the study aimed to:
1. determine the apparent energy, crude protein, dry matter, and ash digestibility
of sweet potato root meal in swine; and
2. determine the apparent digestibility of energy, crude protein, dry matter, and ash
in commercial feeds supplemented with sweet potato root meal in swine.
The study was conducted at Banig, Tawang, La Trinidad, Benguet on February
2012.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
REVIEW OF LITERATURE
Measure of Nutrient Utilization
A knowledge and understanding of nutrient utilization is a necessary step in
evaluating feed stuffs for defining nutrient requirements for the development of feeding
standards for animals. Digestion trials are used to determine the proportion of the nutrient
on the feed or diet that can be absorbed from the gastro-intestinal tract. There are many
methods of digestion trial. One is the conventional or the total collection method, which is
laborious and impractical for many animals. Another is the indicator method in which an
indigestible substance like chromic oxide (Cr203) or natural constituents of feeds like
lignin will be mixed with the diet. The concentration of this indicator substance on the feed
and sample of feces will be determine and an estimate of digestibility will be derived.
According to Mc Donald et al (2002), there are some associated terms derived from
digestibility data, which are intended to provide a measure of the energy value of the food.
One measure is the total digestible nutrient (TDN) constant of the food of digestible crude
protein and digestible carbohydrate (crude fiber and N-free extractive), plus 2.25 times the
weight of digestible either extract. Another derived measured of the energy content of food
is the concentration of digestible organic matter in the dry matter.
Feeding Value
Dominguez (1998) found out that sweet potato root meal contains 5.0% of crude
protein, 0.2% of calcium, 0.14% calcium, and 0.2% of phosphorus. On other study
conducted by Giang et. al. (2002) they analyzed that sweet potato root meal contain 4.0%
of crude protein, 4.0% of calcium and 23% of phosphorus in dry basis.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Yang et al (1975) reported that the crude protein contents of sweet potato varied
from 3.5% to 7.1% on dry weight basis and that protein and lysine contents are significantly
influenced by variation between varieties. The digestible energy (DE), metabolizable
energy (ME), and net energy (NE) of sweet potato chips and corn for pigs have been
estimated by Wu (1980) as cited by Villareal et al (1982). The DE and ME of sweet potato
chips were 91% of those corn while NE of sweet potato chips was only 79% of that of corn.
Thus sweet potato chips are not comparable with corn as a pig diet in terms of either
quantity or quality of digestible energy.
Koh et al (1976) have reported that a daily crude protain intake of 334g and a daily
gross energy intake of 8.5 Mcal result in satisfactory growth performance for growing-
finishing pigs fed diet containing raw sweet potato or dried sweet potato chips. Raw sweet
potatoes as a feed for growing-finishing pigs needs more added soybean meal or some
other protein supplement to obtain satisfactory performance than does a feed of dried sweet
potato chips. The cost per gain of the former is also higher than that of the latter. The above
result indicates that the utilization of sun-dried chips is more economical than use of raw
sweet potatoes. The results of many feeding experiment (Koh et al 1960; Tai and Lei 1970)
confirmed that the performance of pigs fed with dried sweet potato chips was not
comparable to that of pigs fed diet with corn, but daily gain and feed-to-gain ratio were
slightly superior when the pigs were fed diets formulated with drieds sweet potato chips
substituting 25% of the corn in the ration.
All plant parts of sweet potato are utilized as feeds for hog, cattle, rabbit, and goat.
Fresh and sun-dried sweet potato chips that contain about 334g crude protein and 8.5 Mcal
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
can be given daily to pigs. Sun-dried sweet potato chips are more economical than the fresh
one. Back fat is significantly thinner in pigs with diets containing sweet potato (Koh, 1979)
In Korea sweet potato silage is utilized as feed. It was found to be not only a good
feed for hogs but also improves the meat quality (Choon-Jeong, 1992). The silage is mixed
with crushed sweet potato root and rice brain at a ratio of 80:20 (w/w), or crushed sweet
potato roots, vines and leaves and rice brain of a ratio of 60:30:10 (w/w/w) and stored for
one month silos. The mixtures can be use to comprise up to 60% of the total feed
requirement for hog fattening.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
MATERIALS AND METHODS
Materials
The materials used in the study were the following: 9 hogs about four months old
weighing an average of 85 kg, pig pen, weighing scale, record book and pen, stick broom,
dehydrator, foil tray, feeding trough, commercial feeds, non- marketable sweet potato and
chromic oxide serve as the indicator.
Experimental Design
and Treatment
The animals were confined and distributed at random into four treatments following
the Completely Randomized Design (CRD). Each treatment was replicated three times
with one pig serving as a replicate and confined in one pen. Each of the experimental
animals was given sweet potato root meal depending on the treatment.
The different treatments were as follows:
T0. Commercial feeds
T1. Commercial feeds + 300g Sweet Potato root meal
T2. Pure Sweet potato root meal
Preparation of the Ration
The sweet potato storage root ''tocano" was collected at Bad-ayan Buguias, Benguet
and washed. After washing, it was grated and sundried to remove the excess water. Finally,
it was weighed based on the specific amount before it was given to the animals. Feeding
was done twice a day, in the morning and in the afternoon. The dried sweet potato was
mixed to the commercial feeds before giving to the animal.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Fecal Collection
Fecal collection was made over a period of five days commencing when pigs reach
their finishing stage, indicator method was used in this study. The chromic oxide which
serves as the indicator was mixed with the ration. To determine the digestibility of the pure
sweet potato meal, the experimental animal was given the ration for a total of ten days
continuously. The first seven days serve as the pre-experimental period for the animal to
get use to the feed. And the next three days was the collection period. Feces were collected
as frequently as necessary each day. Collected feces was placed in plastic bags and stored
at -100C.
At the end of the collection period, the feces from each pig were oven dried,
thoroughly mixed, and sampled. Approximately 50g feces were taken, the collected
samples were sent to UPLB for analysis.
The following data were gathered:
1. Weight of the pigs at the start of collection (kg). This was the weight of the
experimental animal at the start of the study or experimental period.
2. Feed intake(kg). This was the total feed intake of the individual animals during
the study wherein their fecal outputs were being collected.
3. Fecal output(kg). This was the total fecal output of the animal or the total amount
of feces voided by the animal during five days collection period.
From the above data, the following were computed
1. Nutrient content of feed and feces. The % dry matter, % crude protein, % crude
fiber, % ash, and % crude fat content of both feed and feces were determined using
appropriate analytical procedures in proximate analysis (AOAC, 1965). The % nitrogen
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
free extract was determined by difference. The energy content of both feed and feces was
determined by Bomb calorimetry. The specific procedures were as follows:
a. Dry matter. Dry matter determination of feed was done by using the oven
for 24 hours at 1020.
% dry matter = Original weight – Oven dried weight
Original weight
b. Crude protein. This was determined by using this formula % CP= %N x
6.25, where nitrogen was determined using the Microkjedahl method. Percent
nitrogen was then computed using the formulas:
%N= (T-B) x N x 0.014 = 100
S
Where T= Sample ml
B= Blank ml
N= Normality of Standard Acid – Titrant
S= weight of Sample in Grams
c. Crude fiber. This was determined by using an ether- extracted sample, boiling
in dilute acid, boiling dilute base, filtering, drying, and burning in a furnace.
d. Gross energy of feeds and feces. This was determined using the bomb-
calorimetry technique.
e. Ash. This was determined by the residue remaining after all the combustible
material has been burned off (oxidized completely) in a furnace heated to 500 to 6000 C.
f. Nitrogen free extract. This was determined by the difference by the original
sample weight and the sum of weights of water, ether extract, crude protein, crude fiber,
and ash.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
2. Apparent digestibility of nutrients. This was computed using the formula:
% Indicator in feeds % Nutrient in Feces
AD% = 100 - 100 x x
% Indicator in feces % Nutrient in Feeds
3. Digestible nutrient of feeds and feces. This was determined by using the formula.
Digestible nutrient
Per kg of feeds = 1000g x nutrient in feeds x % digestibility
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
RESULTS AND DISCUSSION
Nutrient Content of Feed Sample
The nutrient content of the different diets used in the study is presented in Table 1.
Analysis showed that the commercial feed contains 92.32 % DM, 4.43% ash, 14.27% CP,
5.90% CF, 3.36% CFi, 64.26% NFE, and 4,078kcal GE/kg. The ration in which 300g
sweet potato was added to 1 kg of commercial contains 90.60% DM, 4.40% ash, 10.84%
CP, 5.11% CF, 5.00% CFi, 65.34% NFE, and 4031kcal GE/kg. On the other hand, sweet
potato meal contains 87.46% DM, 3.84% ash, 1.29% CP, 5.11% CF, 5.00% CFi, 75.34%
NFE and 3,383 kcal GE/kg.
Sauvant et al., (2004) reported that dried sweet potato tuber that contains 87.8%
dry matter has the following nutrient content: 4.25% CP, 2.6% CFi, 0.08% EE, 2.8% ash,
0.2% insoluble ash, 8.0% neutral detergent fiber, 4.2% acid detergent fiber, 0.8% acid
detergent lignin, 64.5% total sugars and 15.2 MJ/kg gross energy.
Dry matter. The nutrient contents of the commercial feeds, 300g sweet potato per
kilogram, and sweet potato contain 92.32%, 90.69%, 87.46% DM. The commercial feeds
obtained the highest percentage in DM followed by the mixture of sweet potato and
Commercial feeds.
Table 1. Nutrient composition of feed of experimental ration
TREATMENT %DM %ASH %CP %CFAT %CFI GE
Kcal/kg
Commercial feeds 92.32 4.43 14.17 5.90 3.56 4078
300g sweet potato 90.69 4.40
10.84 5.11 5.00 4031
/ kg + Cf
Pure sweet potato 87.46 3.84 1.29 2.33 4.66 3383
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
On the other hand sweet potato contains the lowest value of DM. When the
commercial feed mixed with 300g sweet potato the value of the DM decrease compared to
the value of commercial feed due to the low DM content of the sweet potato.
Ash. The ash contents of the commercial feed, 300g sweet potato per kilogram of
commercial feeds and sweet potato diet were 4.43%, 4.40%, and 3.84%. Commercial feed
has the highest ash content of 4.43% followed by of 300g sweet potato per kilogram of
commercial feeds and sweet potato meal which contain 4.40% and3.84% respectively. The
commercial feeds and sweet potato the value of the mixture decreased compared to the
commercial feeds alone and this is because of the low ash content of the sweet potato.
Crude protein. Based on analysis result it shows that the commercial feed has the
highest crude protein content of 14.17% followed by 300g per kilogram of commercial
feeds that contain 10.84%. The value of sweet potato has the lowest crude protein content
of 1.29% compared to the other dietary. The percent CP content of sweet potato of 1.29%
is much lower than the 4.25% reported by Sauvant et al, (2004). Likewise, on the dry
matter basis, sweet potato has lower %CP of 3.5% compared to 7.1% reported by Yang et.
al. (1975). The lower CP content of the mixture of 300g sweet potato meal and commercial
feeds decreases due to the fact that sweet potato has the lowest CP content compared to the
other ration.
Crude fat. The Analysis shows that commercial feed has the highest CF content of
5.90% followed by mixture of 300g sweet potato per kilogram of commercial feeds which
has a value of 5.11%. But the sweet potato has the lowest CF value of 2.33%. When mixing
the commercial feeds and sweet potato, the CF of the mixture decreased compared to the
commercial feeds because of the low CF content of the sweet potato.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Crude fiber. The analysis shows that the 300g sweet potato per kilogram of
commercial feeds has the higher value of CFi which is 3.56% and the sweet potato obtains
4.66%. The lowest value attained from commercial feeds which contain 5.00% of CFi. The
content of the CFi of the mixture of commercial feeds and sweet potato increased compared
to the CFi content of the commercial feeds due to the high crude protein of the sweet potato.
Gross energy. Commercial feeds have the highest value of 4078 kcal/kg followed
by the combination of 300g sweet potato per kilogram of commercial feed which has a
value of 4031 kcal/kg. Lower GE value was obtained in sweet potato with the value of
3383 kcal/kg. The GE content of commercial feeds and sweet potato mixture decreased
compared to the GE content of commercial feed due to the reason of lower gross energy
content of sweet potato. The GE content of sweet potato meal obtained in this study of
3,383kcal GE/kg is equivalent to 15.16 MJ GE/kg, considering that 1 Cal is equivalent to
4.1855 Joules (Pond et al., 2005). This is comparable to the gross energy value of sweet
potato meal reported by Sauvant et al. (2004).
Apparent Digestibility of Nutrient
The apparent digestibility of nutrient in the different test ration in 85 kg hogs
weighing 85 kg. is presented in table 2. The digestibility of nutrients in the commercial
ration were 76.66% for DM, 25.77% for ash, 80.233% for CP, 74.71% for CF, 85.96% for
NFE, and 77.270% for GE. The ration that contain commercial feeds and 300g sweet potato
per kg of commercial feed contain 65.41% for DM, 11.75% for ash, 55.763% for CP,
54.42% for CF, 80.03% for NFE, and 65.437% for GE. The digestibility of nutrient in the
sweet potato meal were 90.06% for DM, 44.76% for ash, 86.01% for CF, 96.06% for NFE,
and 89.337% for GE.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Dry matter. Statistical analysis revealed highly significant differences in the
apparent DM digestibility of the experimental diet obtained from 85 kg hogs. Sweet potato
meal had the highest DM digestibility which is 90.09% followed by commercial feeds
ration of 65.41%. While 300g sweet potato had lowest DM digestibility of 65.41% were
digested by the hog fed. When the commercial feeds and sweet potato were mixed, the dry
matter of the mixture decreased compared to the commercial feeds because of the low dry
matter content of the commercial feeds.
Ash. Statistical analysis revealed no significant differences in the apparent ash
digestibility of the three experimental diets obtain from 85 kg hogs. It means that the
digestibility of ash in hogs fed with the different dietary treatment were more or less the
same. The pure sweet potato has the highest ash digestibility sot means that 44.76% of ash
is being digested by the animal followed by the commercial feeds. While hogs fed with
300gram sweet potato per kilogram commercial feeds have the lowest digested nutrient of
11.75%.
Table 2. Ash, crude protein, crude fat, gross energy, nitrogen free extract, and dry matter
digestibility (%)
TREATMENT DM ASH CP CFAT NFE GE
Commercial feeds 76.66b 25.77 80.233a 74.71a 85.96b 77.270ab
300g sweet potato 65.41b 11.75 55.763b 54.42b 80.03b 65.437b
Per kg of CF
Pure sweet potato 90.06b 44.76 - 86.01a 96.06a 89.377a
When commercial feeds and sweet potato are mixed, the value of the ash digestibility
decrease compared to the value of the commercial feeds due to the low ash digestibility
content of commercial feeds.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Crude protein. Statistical analysis revealed highly significant differences between
the digestibilities of crude protein of hogs given commercial feeds and 300g sweet potato
per kilogram commercial feeds which are 80.233% and 55.763% respectively. Hogs fed
with commercial feeds have the highest crude protein digestibility of 80.233% which is
being utilized by the animal while 55.763% which is the lowest is digested by the hogs fed
with 300gram sweet potato per kilogram commercial feeds which is the lowest. Due to
some factors which affect the fecal sample of the hogs fed with sweet potato the value of
the crude protein is negative.
Crude fat. Basing on the statistical analysis there were highly significant differences
in the digestibility of crude fat in hogs fed with commercial feeds, 300gram sweet potato
per kilogram commercial feeds and pure sweet potato. 85 kg hogs fed with pure sweet
potato obtain the highest crude fat digestibility of 86.01% which is used by the animal
followed by the commercial feeds of 74.71%. Hogs fed with 300g sweet potato per
kilogram commercial feeds have the lowest crude digestibility of 54.42%. When the
commercial feeds and sweet potato are mixed together, the crude fat value decreased
compared to the crude fat value of commercial feeds due to the higher crude fat digestibility
content of the sweet potato.
Nitrogen free extract. Statistical analysis showed that there are highly significant
differences in the digestibility of nitrogen free extract of hogs among treatment. This shows
that the hog fed with pure sweet potato has the highest nitrogen free extract digestibility of
96.06% followed by the commercial feeds of 85.96%, while 300g sweet potato per
kilogram of commercial feeds has 80.03% which is the lowest among the treatment.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Gross energy. Statistical analysis shows that there were highly significant
differences among treatment. It shows that the pig fed with pure sweet potato has the
highest gross energy digestibility of 89.377% followed by the commercial feeds of
77.270%, while 300g sweet potato per kilogram of have the lowest digested gross energy
of 65.437%.
Digestible Nutrient per Kilogram
Basing on the nutrient content of the diet and the percent digestibility obtained
from 85kg hogs, the digestible nutrient in the different ration are present in the table 3. The
digestible nutrients per kilogram of commercial in hogs contain 707.73g DM, 11.41g ash,
113.687g CP, 44.08g CF, 552.35g NFE, and 3151 GE. On the other hand, 300g sweet
potato per kilogram of commercial feeds contain 593.22g DM, 5.17g ash, 60.447g CP,
27.81g CF, 522.91g NFE, and 2637.667g GE. The digestible nutrients of sweet potato
contain 787.89g DM, 17.19g ash, 20.04g CF, 723.73g NFE, and 3023.667g GE.
Table 3. Digestible nutrients in 1000g of the ration
TREATMENT DM ASH CP CFAT NFE GE
Pure commercial 707.73a 11.41 113.687a 44.08a 552.35b 3151.000
feeds
300g sweet potato 593.22b 5.17 60.447b 27.81b 522.91b 2637.667
+ CF
Pure sweet potato 787.89b 17.19 - 20.04b 723.73a 3023.667
Koh et al (1976) have reported that a daily crude protein intake of pigs is 334g and
daily gross energy intake of 8.5Mcal result in satisfactory growth performance for growing
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
pigs. Based on the book value, the gross energy content of most feeds vary within a narrow
range from 17% to 20% Mj/kg DM.
Dry matter. Statistical analysis revealed significant differences in the DM content
among the 3 rations. Sweet potato has the highest digestible dry matter of 787.89g/kg
followed by the commercial feeds which contain 707.73g/kg. The sweet potato and
commercial feeds mixture contain the lowest value of dry matter of 593.22g/kg.
Ash. Statistical analysis showed no significant differences in the digestible ash
content among the 3 experimental rations. 85kg Hogs fed with pure sweet potato obtained
the highest digestible nutrient per kilogram of ash which contain 17.19% followed by the
11.41% commercial feed. The commercial feeds and sweet potato mixture contains the
lowest ash value of 5.17% because the mineral like calcium and phosphorus is being
absorbed and utilized by the animal fed with sweet potato.
Crude protein. Statistical analysis revealed highly significant differences in the
digestible CP of the 3 experimental rations. Commercial feeds obtain the highest digestible
nutrient in crude protein of 113.687 per kilogram followed by 60.447% 300g sweet potato
per kilogram of commercial feeds. This mean that the amino acids, gycolipids and B-
vitamins which are contain by crude protein in commercial feeds were absorbed and
utilized by the hog fed with commercial feeds.
Crude fat. Highly significant difference is observed among the treatments as the
statistical analysis revealed. The highest crude fat digestible nutrient of 44.08g is obtained
by the pigs fed with commercial feeds followed by the 300g sweet potato per kilogram of
commercial feeds.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Nitrogen free extract. Statistical analysis revealed highly significant differences
among the treatment. The pigs fed with pure sweet potato have the highest digestible
nutrient of nitrogen free extract of 723.73g. This is due to the fact that sweet potato contain
high nitrogen free extract fraction which indicates its potential value as energy source.
Gross energy. The statistical analysis revealed that there is no significant difference
among the treatment. It means that the digestible nutrient per kilogram in hogs fed with
different dietary treatment were more or less the same. Commercial feeds obtained the
highest digestible nutrient per kilogram of 3151kcal/kg followed by the 3023.667kcal/kg
sweet potato while 2637.667 kcal/kg were obtain in the 300g sweet potato per kilogram of
commercial feeds.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
SUMMARY, CONCLUSION AND RECOMMENDATION
Summary
The study was conducted to determine the apparent digestibility and digestible
nutrient per kilogram of commercial feeds, 300gram sweet potato + commercial feed and
pure sweet potato in pigs. In terms of ash, crude protein, crude fat, gross energy, nitrogen-
free extract, and the dry matter.
Results showed that commercial feed contains 92.32 % DM, 4.43% ash, 14.27%
CP, 5.90% CF, 3.36% CFi, 64.26% NFE, and 4,078kcal GE/kg, while the ration in which
300g sweet potato was added to 1 kg of commercial contains 90.60% DM, 4.40% ash,
10.84% CP, 5.11% CF, 5.00% CFi, 65.34% NFE, and 4031kcal GE/kg. On the other hand,
sweet potato meal contains 87.46% DM, 3.84% ash, 1.29% CP, 5.11% CF, 5.00% CFi,
75.34% NFE, and 3,383 kcal GE/kg.
The digestibility of nutrients in the commercial ration were 76.66% for DM,
25.77% for ash, 80.233% for CP, 74.71% for CF, 85.96% for NFE, and 77.270% for GE.
The ration that contains commercial feeds and 300g sweet potato per kg of commercial
feed contain 65.41% for DM, 11.75% for ash, 55.763% for CP, 54.42% for CF, 80.03%
for NFE, and 65.437% for GE. While the digestibility of nutrient in the sweet potato meal
were 90.06% for DM, 44.76% for ash, 86.01% for CF, 96.06% for NFE, and 89.337% for
GE.
The computed digestible nutrients per kilogram of ration were 707.73g DM, 11.41g
ash, 113.687g CP, 44.08g CF, 552.35g NFE, and 3151 GE for the commercial feed;
593.22g DM, 5.17g ash, 60.447g CP, 27.81g CF, 522.91g NFE and 2637.667g GE for 300g
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
SPM/kg ration; and 787.89g DM, 17.19g ash, 20.04g CF, 723.73g NFE and 3023.667g GE
for the sweet potato meal.
Statistical analysis showed there are highly significant differences in terms of
digestibility of crude protein, crude fat, gross energy, nitrogen- free extract and the dry
matter. In terms of digestible nutrient per kilogram, the crude protein, crude fat, nitrogen
free extract, dry matter, statistical revealed highly significant differences.
Conclusion
From the result of the study, sweet potato is a good feed supplement to swine ration
because it contains the necessary nutrient needed by the pigs for its optimum performance.
Recommendation
It is therefore recommended that sweet potato is a good supplement diet to pig. It
is also recommended that further study in the digestibility of sweet potato using different
stage of pigs from weanling to finishing to be conducted
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
LITERATURE CITED
ASSOCIATION OF OFFICIAL AGRICULTURE CHEMIST. 1965. Official Method of
Analysis. (10th edition).
GIANG, H. H. LY V. L. AND OGLE. 2002. Evaluation of Digestibility of Mixture of
Sweet Potato vines and roots in booth Silage and Dry form by F1 Crossbreed
Fattening Pigs. Department of Animal Nutrition and Management Swedish
University of Agricultural Science Uppsala, Sweden.
KOH, K.F, CHOW, W.C, and TAI. 1960. Comparative Feeding Value Yellow Corn and
Sweet Potato, Dried Sweet potato Chips for Growing – Finishing Pigs. Farm
Anim. Breeding Sta. Taiwan Sugar Corp. Chunan, Republic of China.
KOH, F.K, T.P, YEH, and H.T. YEN. 1976. Effect of Feeding Sweet Potatoes, Dried
SweetPotato Chips and Sweat Potato Vine on the Growth Performance of Growing-
Finishing Pigs. J. Chinese Soc. Anim. Sci. Pp 55-57
KOH, K. F, and C. P. CHEN. 1979. Studies on the Utilization of Sweet Potatoes Chips and
Cassava pomace for Swine. J. Agric. Asso. China. Pp 45-54.
McDONALD P. E, R.A, GREENHALGH, JF,D. and C.A MORGAN. 2002. Animal
Nutrition. Fifth edition. Longman Scientific and
Technical,
Longman
Group Limited, Longman house, Burn Mill, Harlow, Essex CM20, 2JE, England.
POND W.G. CHURCH D.G. POND K. R. and SCHOKNECHT P. A. 2005. Basic Animal
Nutrition and Feeding. Animal Science Cornell University, New York. Pp 49-52
SAUVANT, D., PEREZ, J. M. and TRAN, G. 2004. Table of Composition and Nutritional
Value of feeds materials. Wageningen Academic, Netherlands. Pp 26-27
VILLAREAL, R. L. and GRIGGS, T. D. 1982. Sweet Potato. Proceeding of the First
International Symposium. Asian Vegetable Research and Development Center.
Shanhua, Tainan, Taiwan, China. P. 385.
YANG, T. H, TAI, Y. C. SHEN, H. S, KO, S. W, and BLACKWELL, R. O. 1975. Protein
content and its amino acid distribution of locally produced and sweet potato in
Taiwan. (in Chinese). 5. Chinese Agric. Chem. Soc. Pp 132 – 138.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
AGUSTIN, FERNAN B., April 2012. Evaluation of Digestibility of Sweet Potato
Meal in Swine. Benguet State University, La Trinidad, Benguet.
Adviser: Marlene B. Atinyao, Ph.D
ABSTRACT
The study was conducted to determine the apparent digestibility of nutrients of
sweet potato meal and commercial feeds supplemented with sweet potato in swine
conducted at Banig, Tawang La Trinidad ,Benguet on February 2012.
A total of nine hogs weighing 85kg per head were distributed using the Completely
Randomized Design (CRD) to the three treatments as follows: commercial feeds, 300g
sweet potato per kilogram of feeds and sweet potato meal.
Analysis showed that sweet potato meal contains 87.46% dry matter, 3.84% ash,
1.29% crude protein, 5.11% crude fat, 5.00% crude fiber, 75.34% nitrogen free extract and
3,383 kcal GE/kg. The digestibility of nutrient in sweet potato meal were as follows:
90.06% for dry matter, 44.76% for ash, 86.01% for crude fat, 96.06% for nitrogen free
extract, and 89.337% for gross energy. The digestibility of nutrients in the commercial
ration were 76.66% for DM, 25.77% for ash, 80.233% for CP, 74.71% for CF, 85.96% for
NFE, 77.270% for GE. The ration that contain commercial feeds and 300g sweet potato
per kg of commercial feed contain 65.41% for DM, 11.75% for ash, 55.763% for CP,
54.42% for CF, 80.03% for NFE, and 65.437% for GE. The digestible nutrient per kg of
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
sweet potato meal was computed as follows: 787.89g dry matter, 17.19g ash, 20.04g crude
fat, 723.73g nitrogen free extract and 3023.667g gross energy.
Statistical analysis showed there are highly significant differences in terms of
digestibility of crude protein, crude fat, gross energy, nitrogen-free extract and the dry
matter and in the digestible nutrient per kilogram of crude protein, crude fat, nitrogen free
extract, dry matter.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
INTRODUCTION
Sweet potato protein is of high nutritive value since it contains reasonable amount
of amino acids. It can provide enough nutrients needed by the animal for maximum
performance. The energy that pigs can get from the sweet potato storage root is similar to
what they get from cassava meal and maize (Quinio, 1986). Although imported corn rather
than sweet potato is widely and very efficiently used as a main carbohydrate source for
pigs diets in our feed industry at the present time, continuous effort have been made to
obtain better utilization of sweet potato as animal feeds. Grown the whole year round, it is
used both food for human and as feed for domestic animals. Sweet potato roots posses
several advantages to the use as a common animal feedstuff, a minimum of culturing
manipulation. But farmer in the Cordillera have limited information in proper processing
of sweet potato for animal feeds. To maximize the use of sweet potato as swine feedstuff,
it is important to know how much of the nutrients sweet potato could be digested by swine.
Knowing the digestibility coefficient of nutrients in sweet potato in swine will
provide a better understanding on how swine utilized sweet potato. It also provides a better
basis for formulating ration using sweet potato meal as feed source. This information could
be used by researcher, animal raisers and students interested in swine production.
The study aimed to determine the utilization of the nutrients in sweet potato meal
through digestibility.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Specifically, the study aimed to:
1. determine the apparent energy, crude protein, dry matter, and ash digestibility
of sweet potato root meal in swine; and
2. determine the apparent digestibility of energy, crude protein, dry matter, and ash
in commercial feeds supplemented with sweet potato root meal in swine.
The study was conducted at Banig, Tawang, La Trinidad, Benguet on February
2012.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
REVIEW OF LITERATURE
Measure of Nutrient Utilization
A knowledge and understanding of nutrient utilization is a necessary step in
evaluating feed stuffs for defining nutrient requirements for the development of feeding
standards for animals. Digestion trials are used to determine the proportion of the nutrient
on the feed or diet that can be absorbed from the gastro-intestinal tract. There are many
methods of digestion trial. One is the conventional or the total collection method, which is
laborious and impractical for many animals. Another is the indicator method in which an
indigestible substance like chromic oxide (Cr203) or natural constituents of feeds like
lignin will be mixed with the diet. The concentration of this indicator substance on the feed
and sample of feces will be determine and an estimate of digestibility will be derived.
According to Mc Donald et al (2002), there are some associated terms derived from
digestibility data, which are intended to provide a measure of the energy value of the food.
One measure is the total digestible nutrient (TDN) constant of the food of digestible crude
protein and digestible carbohydrate (crude fiber and N-free extractive), plus 2.25 times the
weight of digestible either extract. Another derived measured of the energy content of food
is the concentration of digestible organic matter in the dry matter.
Feeding Value
Dominguez (1998) found out that sweet potato root meal contains 5.0% of crude
protein, 0.2% of calcium, 0.14% calcium, and 0.2% of phosphorus. On other study
conducted by Giang et. al. (2002) they analyzed that sweet potato root meal contain 4.0%
of crude protein, 4.0% of calcium and 23% of phosphorus in dry basis.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Yang et al (1975) reported that the crude protein contents of sweet potato varied
from 3.5% to 7.1% on dry weight basis and that protein and lysine contents are significantly
influenced by variation between varieties. The digestible energy (DE), metabolizable
energy (ME), and net energy (NE) of sweet potato chips and corn for pigs have been
estimated by Wu (1980) as cited by Villareal et al (1982). The DE and ME of sweet potato
chips were 91% of those corn while NE of sweet potato chips was only 79% of that of corn.
Thus sweet potato chips are not comparable with corn as a pig diet in terms of either
quantity or quality of digestible energy.
Koh et al (1976) have reported that a daily crude protain intake of 334g and a daily
gross energy intake of 8.5 Mcal result in satisfactory growth performance for growing-
finishing pigs fed diet containing raw sweet potato or dried sweet potato chips. Raw sweet
potatoes as a feed for growing-finishing pigs needs more added soybean meal or some
other protein supplement to obtain satisfactory performance than does a feed of dried sweet
potato chips. The cost per gain of the former is also higher than that of the latter. The above
result indicates that the utilization of sun-dried chips is more economical than use of raw
sweet potatoes. The results of many feeding experiment (Koh et al 1960; Tai and Lei 1970)
confirmed that the performance of pigs fed with dried sweet potato chips was not
comparable to that of pigs fed diet with corn, but daily gain and feed-to-gain ratio were
slightly superior when the pigs were fed diets formulated with drieds sweet potato chips
substituting 25% of the corn in the ration.
All plant parts of sweet potato are utilized as feeds for hog, cattle, rabbit, and goat.
Fresh and sun-dried sweet potato chips that contain about 334g crude protein and 8.5 Mcal
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
can be given daily to pigs. Sun-dried sweet potato chips are more economical than the fresh
one. Back fat is significantly thinner in pigs with diets containing sweet potato (Koh, 1979)
In Korea sweet potato silage is utilized as feed. It was found to be not only a good
feed for hogs but also improves the meat quality (Choon-Jeong, 1992). The silage is mixed
with crushed sweet potato root and rice brain at a ratio of 80:20 (w/w), or crushed sweet
potato roots, vines and leaves and rice brain of a ratio of 60:30:10 (w/w/w) and stored for
one month silos. The mixtures can be use to comprise up to 60% of the total feed
requirement for hog fattening.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
MATERIALS AND METHODS
Materials
The materials used in the study were the following: 9 hogs about four months old
weighing an average of 85 kg, pig pen, weighing scale, record book and pen, stick broom,
dehydrator, foil tray, feeding trough, commercial feeds, non- marketable sweet potato and
chromic oxide serve as the indicator.
Experimental Design
and Treatment
The animals were confined and distributed at random into four treatments following
the Completely Randomized Design (CRD). Each treatment was replicated three times
with one pig serving as a replicate and confined in one pen. Each of the experimental
animals was given sweet potato root meal depending on the treatment.
The different treatments were as follows:
T0. Commercial feeds
T1. Commercial feeds + 300g Sweet Potato root meal
T2. Pure Sweet potato root meal
Preparation of the Ration
The sweet potato storage root ''tocano" was collected at Bad-ayan Buguias, Benguet
and washed. After washing, it was grated and sundried to remove the excess water. Finally,
it was weighed based on the specific amount before it was given to the animals. Feeding
was done twice a day, in the morning and in the afternoon. The dried sweet potato was
mixed to the commercial feeds before giving to the animal.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Fecal Collection
Fecal collection was made over a period of five days commencing when pigs reach
their finishing stage, indicator method was used in this study. The chromic oxide which
serves as the indicator was mixed with the ration. To determine the digestibility of the pure
sweet potato meal, the experimental animal was given the ration for a total of ten days
continuously. The first seven days serve as the pre-experimental period for the animal to
get use to the feed. And the next three days was the collection period. Feces were collected
as frequently as necessary each day. Collected feces was placed in plastic bags and stored
at -100C.
At the end of the collection period, the feces from each pig were oven dried,
thoroughly mixed, and sampled. Approximately 50g feces were taken, the collected
samples were sent to UPLB for analysis.
The following data were gathered:
1. Weight of the pigs at the start of collection (kg). This was the weight of the
experimental animal at the start of the study or experimental period.
2. Feed intake(kg). This was the total feed intake of the individual animals during
the study wherein their fecal outputs were being collected.
3. Fecal output(kg). This was the total fecal output of the animal or the total amount
of feces voided by the animal during five days collection period.
From the above data, the following were computed
1. Nutrient content of feed and feces. The % dry matter, % crude protein, % crude
fiber, % ash, and % crude fat content of both feed and feces were determined using
appropriate analytical procedures in proximate analysis (AOAC, 1965). The % nitrogen
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
free extract was determined by difference. The energy content of both feed and feces was
determined by Bomb calorimetry. The specific procedures were as follows:
a. Dry matter. Dry matter determination of feed was done by using the oven
for 24 hours at 1020.
% dry matter = Original weight – Oven dried weight
Original weight
b. Crude protein. This was determined by using this formula % CP= %N x
6.25, where nitrogen was determined using the Microkjedahl method. Percent
nitrogen was then computed using the formulas:
%N= (T-B) x N x 0.014 = 100
S
Where T= Sample ml
B= Blank ml
N= Normality of Standard Acid – Titrant
S= weight of Sample in Grams
c. Crude fiber. This was determined by using an ether- extracted sample, boiling
in dilute acid, boiling dilute base, filtering, drying, and burning in a furnace.
d. Gross energy of feeds and feces. This was determined using the bomb-
calorimetry technique.
e. Ash. This was determined by the residue remaining after all the combustible
material has been burned off (oxidized completely) in a furnace heated to 500 to 6000 C.
f. Nitrogen free extract. This was determined by the difference by the original
sample weight and the sum of weights of water, ether extract, crude protein, crude fiber,
and ash.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
2. Apparent digestibility of nutrients. This was computed using the formula:
% Indicator in feeds % Nutrient in Feces
AD% = 100 - 100 x x
% Indicator in feces % Nutrient in Feeds
3. Digestible nutrient of feeds and feces. This was determined by using the formula.
Digestible nutrient
Per kg of feeds = 1000g x nutrient in feeds x % digestibility
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
RESULTS AND DISCUSSION
Nutrient Content of Feed Sample
The nutrient content of the different diets used in the study is presented in Table 1.
Analysis showed that the commercial feed contains 92.32 % DM, 4.43% ash, 14.27% CP,
5.90% CF, 3.36% CFi, 64.26% NFE, and 4,078kcal GE/kg. The ration in which 300g
sweet potato was added to 1 kg of commercial contains 90.60% DM, 4.40% ash, 10.84%
CP, 5.11% CF, 5.00% CFi, 65.34% NFE, and 4031kcal GE/kg. On the other hand, sweet
potato meal contains 87.46% DM, 3.84% ash, 1.29% CP, 5.11% CF, 5.00% CFi, 75.34%
NFE and 3,383 kcal GE/kg.
Sauvant et al., (2004) reported that dried sweet potato tuber that contains 87.8%
dry matter has the following nutrient content: 4.25% CP, 2.6% CFi, 0.08% EE, 2.8% ash,
0.2% insoluble ash, 8.0% neutral detergent fiber, 4.2% acid detergent fiber, 0.8% acid
detergent lignin, 64.5% total sugars and 15.2 MJ/kg gross energy.
Dry matter. The nutrient contents of the commercial feeds, 300g sweet potato per
kilogram, and sweet potato contain 92.32%, 90.69%, 87.46% DM. The commercial feeds
obtained the highest percentage in DM followed by the mixture of sweet potato and
Commercial feeds.
Table 1. Nutrient composition of feed of experimental ration
TREATMENT %DM %ASH %CP %CFAT %CFI GE
Kcal/kg
Commercial feeds 92.32 4.43 14.17 5.90 3.56 4078
300g sweet potato 90.69 4.40
10.84 5.11 5.00 4031
/ kg + Cf
Pure sweet potato 87.46 3.84 1.29 2.33 4.66 3383
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
On the other hand sweet potato contains the lowest value of DM. When the
commercial feed mixed with 300g sweet potato the value of the DM decrease compared to
the value of commercial feed due to the low DM content of the sweet potato.
Ash. The ash contents of the commercial feed, 300g sweet potato per kilogram of
commercial feeds and sweet potato diet were 4.43%, 4.40%, and 3.84%. Commercial feed
has the highest ash content of 4.43% followed by of 300g sweet potato per kilogram of
commercial feeds and sweet potato meal which contain 4.40% and3.84% respectively. The
commercial feeds and sweet potato the value of the mixture decreased compared to the
commercial feeds alone and this is because of the low ash content of the sweet potato.
Crude protein. Based on analysis result it shows that the commercial feed has the
highest crude protein content of 14.17% followed by 300g per kilogram of commercial
feeds that contain 10.84%. The value of sweet potato has the lowest crude protein content
of 1.29% compared to the other dietary. The percent CP content of sweet potato of 1.29%
is much lower than the 4.25% reported by Sauvant et al, (2004). Likewise, on the dry
matter basis, sweet potato has lower %CP of 3.5% compared to 7.1% reported by Yang et.
al. (1975). The lower CP content of the mixture of 300g sweet potato meal and commercial
feeds decreases due to the fact that sweet potato has the lowest CP content compared to the
other ration.
Crude fat. The Analysis shows that commercial feed has the highest CF content of
5.90% followed by mixture of 300g sweet potato per kilogram of commercial feeds which
has a value of 5.11%. But the sweet potato has the lowest CF value of 2.33%. When mixing
the commercial feeds and sweet potato, the CF of the mixture decreased compared to the
commercial feeds because of the low CF content of the sweet potato.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Crude fiber. The analysis shows that the 300g sweet potato per kilogram of
commercial feeds has the higher value of CFi which is 3.56% and the sweet potato obtains
4.66%. The lowest value attained from commercial feeds which contain 5.00% of CFi. The
content of the CFi of the mixture of commercial feeds and sweet potato increased compared
to the CFi content of the commercial feeds due to the high crude protein of the sweet potato.
Gross energy. Commercial feeds have the highest value of 4078 kcal/kg followed
by the combination of 300g sweet potato per kilogram of commercial feed which has a
value of 4031 kcal/kg. Lower GE value was obtained in sweet potato with the value of
3383 kcal/kg. The GE content of commercial feeds and sweet potato mixture decreased
compared to the GE content of commercial feed due to the reason of lower gross energy
content of sweet potato. The GE content of sweet potato meal obtained in this study of
3,383kcal GE/kg is equivalent to 15.16 MJ GE/kg, considering that 1 Cal is equivalent to
4.1855 Joules (Pond et al., 2005). This is comparable to the gross energy value of sweet
potato meal reported by Sauvant et al. (2004).
Apparent Digestibility of Nutrient
The apparent digestibility of nutrient in the different test ration in 85 kg hogs
weighing 85 kg. is presented in table 2. The digestibility of nutrients in the commercial
ration were 76.66% for DM, 25.77% for ash, 80.233% for CP, 74.71% for CF, 85.96% for
NFE, and 77.270% for GE. The ration that contain commercial feeds and 300g sweet potato
per kg of commercial feed contain 65.41% for DM, 11.75% for ash, 55.763% for CP,
54.42% for CF, 80.03% for NFE, and 65.437% for GE. The digestibility of nutrient in the
sweet potato meal were 90.06% for DM, 44.76% for ash, 86.01% for CF, 96.06% for NFE,
and 89.337% for GE.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Dry matter. Statistical analysis revealed highly significant differences in the
apparent DM digestibility of the experimental diet obtained from 85 kg hogs. Sweet potato
meal had the highest DM digestibility which is 90.09% followed by commercial feeds
ration of 65.41%. While 300g sweet potato had lowest DM digestibility of 65.41% were
digested by the hog fed. When the commercial feeds and sweet potato were mixed, the dry
matter of the mixture decreased compared to the commercial feeds because of the low dry
matter content of the commercial feeds.
Ash. Statistical analysis revealed no significant differences in the apparent ash
digestibility of the three experimental diets obtain from 85 kg hogs. It means that the
digestibility of ash in hogs fed with the different dietary treatment were more or less the
same. The pure sweet potato has the highest ash digestibility sot means that 44.76% of ash
is being digested by the animal followed by the commercial feeds. While hogs fed with
300gram sweet potato per kilogram commercial feeds have the lowest digested nutrient of
11.75%.
Table 2. Ash, crude protein, crude fat, gross energy, nitrogen free extract, and dry matter
digestibility (%)
TREATMENT DM ASH CP CFAT NFE GE
Commercial feeds 76.66b 25.77 80.233a 74.71a 85.96b 77.270ab
300g sweet potato 65.41b 11.75 55.763b 54.42b 80.03b 65.437b
Per kg of CF
Pure sweet potato 90.06b 44.76 - 86.01a 96.06a 89.377a
When commercial feeds and sweet potato are mixed, the value of the ash digestibility
decrease compared to the value of the commercial feeds due to the low ash digestibility
content of commercial feeds.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Crude protein. Statistical analysis revealed highly significant differences between
the digestibilities of crude protein of hogs given commercial feeds and 300g sweet potato
per kilogram commercial feeds which are 80.233% and 55.763% respectively. Hogs fed
with commercial feeds have the highest crude protein digestibility of 80.233% which is
being utilized by the animal while 55.763% which is the lowest is digested by the hogs fed
with 300gram sweet potato per kilogram commercial feeds which is the lowest. Due to
some factors which affect the fecal sample of the hogs fed with sweet potato the value of
the crude protein is negative.
Crude fat. Basing on the statistical analysis there were highly significant differences
in the digestibility of crude fat in hogs fed with commercial feeds, 300gram sweet potato
per kilogram commercial feeds and pure sweet potato. 85 kg hogs fed with pure sweet
potato obtain the highest crude fat digestibility of 86.01% which is used by the animal
followed by the commercial feeds of 74.71%. Hogs fed with 300g sweet potato per
kilogram commercial feeds have the lowest crude digestibility of 54.42%. When the
commercial feeds and sweet potato are mixed together, the crude fat value decreased
compared to the crude fat value of commercial feeds due to the higher crude fat digestibility
content of the sweet potato.
Nitrogen free extract. Statistical analysis showed that there are highly significant
differences in the digestibility of nitrogen free extract of hogs among treatment. This shows
that the hog fed with pure sweet potato has the highest nitrogen free extract digestibility of
96.06% followed by the commercial feeds of 85.96%, while 300g sweet potato per
kilogram of commercial feeds has 80.03% which is the lowest among the treatment.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Gross energy. Statistical analysis shows that there were highly significant
differences among treatment. It shows that the pig fed with pure sweet potato has the
highest gross energy digestibility of 89.377% followed by the commercial feeds of
77.270%, while 300g sweet potato per kilogram of have the lowest digested gross energy
of 65.437%.
Digestible Nutrient per Kilogram
Basing on the nutrient content of the diet and the percent digestibility obtained
from 85kg hogs, the digestible nutrient in the different ration are present in the table 3. The
digestible nutrients per kilogram of commercial in hogs contain 707.73g DM, 11.41g ash,
113.687g CP, 44.08g CF, 552.35g NFE, and 3151 GE. On the other hand, 300g sweet
potato per kilogram of commercial feeds contain 593.22g DM, 5.17g ash, 60.447g CP,
27.81g CF, 522.91g NFE, and 2637.667g GE. The digestible nutrients of sweet potato
contain 787.89g DM, 17.19g ash, 20.04g CF, 723.73g NFE, and 3023.667g GE.
Table 3. Digestible nutrients in 1000g of the ration
TREATMENT DM ASH CP CFAT NFE GE
Pure commercial 707.73a 11.41 113.687a 44.08a 552.35b 3151.000
feeds
300g sweet potato 593.22b 5.17 60.447b 27.81b 522.91b 2637.667
+ CF
Pure sweet potato 787.89b 17.19 - 20.04b 723.73a 3023.667
Koh et al (1976) have reported that a daily crude protein intake of pigs is 334g and
daily gross energy intake of 8.5Mcal result in satisfactory growth performance for growing
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
pigs. Based on the book value, the gross energy content of most feeds vary within a narrow
range from 17% to 20% Mj/kg DM.
Dry matter. Statistical analysis revealed significant differences in the DM content
among the 3 rations. Sweet potato has the highest digestible dry matter of 787.89g/kg
followed by the commercial feeds which contain 707.73g/kg. The sweet potato and
commercial feeds mixture contain the lowest value of dry matter of 593.22g/kg.
Ash. Statistical analysis showed no significant differences in the digestible ash
content among the 3 experimental rations. 85kg Hogs fed with pure sweet potato obtained
the highest digestible nutrient per kilogram of ash which contain 17.19% followed by the
11.41% commercial feed. The commercial feeds and sweet potato mixture contains the
lowest ash value of 5.17% because the mineral like calcium and phosphorus is being
absorbed and utilized by the animal fed with sweet potato.
Crude protein. Statistical analysis revealed highly significant differences in the
digestible CP of the 3 experimental rations. Commercial feeds obtain the highest digestible
nutrient in crude protein of 113.687 per kilogram followed by 60.447% 300g sweet potato
per kilogram of commercial feeds. This mean that the amino acids, gycolipids and B-
vitamins which are contain by crude protein in commercial feeds were absorbed and
utilized by the hog fed with commercial feeds.
Crude fat. Highly significant difference is observed among the treatments as the
statistical analysis revealed. The highest crude fat digestible nutrient of 44.08g is obtained
by the pigs fed with commercial feeds followed by the 300g sweet potato per kilogram of
commercial feeds.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
Nitrogen free extract. Statistical analysis revealed highly significant differences
among the treatment. The pigs fed with pure sweet potato have the highest digestible
nutrient of nitrogen free extract of 723.73g. This is due to the fact that sweet potato contain
high nitrogen free extract fraction which indicates its potential value as energy source.
Gross energy. The statistical analysis revealed that there is no significant difference
among the treatment. It means that the digestible nutrient per kilogram in hogs fed with
different dietary treatment were more or less the same. Commercial feeds obtained the
highest digestible nutrient per kilogram of 3151kcal/kg followed by the 3023.667kcal/kg
sweet potato while 2637.667 kcal/kg were obtain in the 300g sweet potato per kilogram of
commercial feeds.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
SUMMARY, CONCLUSION AND RECOMMENDATION
Summary
The study was conducted to determine the apparent digestibility and digestible
nutrient per kilogram of commercial feeds, 300gram sweet potato + commercial feed and
pure sweet potato in pigs. In terms of ash, crude protein, crude fat, gross energy, nitrogen-
free extract, and the dry matter.
Results showed that commercial feed contains 92.32 % DM, 4.43% ash, 14.27%
CP, 5.90% CF, 3.36% CFi, 64.26% NFE, and 4,078kcal GE/kg, while the ration in which
300g sweet potato was added to 1 kg of commercial contains 90.60% DM, 4.40% ash,
10.84% CP, 5.11% CF, 5.00% CFi, 65.34% NFE, and 4031kcal GE/kg. On the other hand,
sweet potato meal contains 87.46% DM, 3.84% ash, 1.29% CP, 5.11% CF, 5.00% CFi,
75.34% NFE, and 3,383 kcal GE/kg.
The digestibility of nutrients in the commercial ration were 76.66% for DM,
25.77% for ash, 80.233% for CP, 74.71% for CF, 85.96% for NFE, and 77.270% for GE.
The ration that contains commercial feeds and 300g sweet potato per kg of commercial
feed contain 65.41% for DM, 11.75% for ash, 55.763% for CP, 54.42% for CF, 80.03%
for NFE, and 65.437% for GE. While the digestibility of nutrient in the sweet potato meal
were 90.06% for DM, 44.76% for ash, 86.01% for CF, 96.06% for NFE, and 89.337% for
GE.
The computed digestible nutrients per kilogram of ration were 707.73g DM, 11.41g
ash, 113.687g CP, 44.08g CF, 552.35g NFE, and 3151 GE for the commercial feed;
593.22g DM, 5.17g ash, 60.447g CP, 27.81g CF, 522.91g NFE and 2637.667g GE for 300g
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
SPM/kg ration; and 787.89g DM, 17.19g ash, 20.04g CF, 723.73g NFE and 3023.667g GE
for the sweet potato meal.
Statistical analysis showed there are highly significant differences in terms of
digestibility of crude protein, crude fat, gross energy, nitrogen- free extract and the dry
matter. In terms of digestible nutrient per kilogram, the crude protein, crude fat, nitrogen
free extract, dry matter, statistical revealed highly significant differences.
Conclusion
From the result of the study, sweet potato is a good feed supplement to swine ration
because it contains the necessary nutrient needed by the pigs for its optimum performance.
Recommendation
It is therefore recommended that sweet potato is a good supplement diet to pig. It
is also recommended that further study in the digestibility of sweet potato using different
stage of pigs from weanling to finishing to be conducted
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012
LITERATURE CITED
ASSOCIATION OF OFFICIAL AGRICULTURE CHEMIST. 1965. Official Method of
Analysis. (10th edition).
GIANG, H. H. LY V. L. AND OGLE. 2002. Evaluation of Digestibility of Mixture of
Sweet Potato vines and roots in booth Silage and Dry form by F1 Crossbreed
Fattening Pigs. Department of Animal Nutrition and Management Swedish
University of Agricultural Science Uppsala, Sweden.
KOH, K.F, CHOW, W.C, and TAI. 1960. Comparative Feeding Value Yellow Corn and
Sweet Potato, Dried Sweet potato Chips for Growing – Finishing Pigs. Farm
Anim. Breeding Sta. Taiwan Sugar Corp. Chunan, Republic of China.
KOH, F.K, T.P, YEH, and H.T. YEN. 1976. Effect of Feeding Sweet Potatoes, Dried
SweetPotato Chips and Sweat Potato Vine on the Growth Performance of Growing-
Finishing Pigs. J. Chinese Soc. Anim. Sci. Pp 55-57
KOH, K. F, and C. P. CHEN. 1979. Studies on the Utilization of Sweet Potatoes Chips and
Cassava pomace for Swine. J. Agric. Asso. China. Pp 45-54.
McDONALD P. E, R.A, GREENHALGH, JF,D. and C.A MORGAN. 2002. Animal
Nutrition. Fifth edition. Longman Scientific and
Technical,
Longman
Group Limited, Longman house, Burn Mill, Harlow, Essex CM20, 2JE, England.
POND W.G. CHURCH D.G. POND K. R. and SCHOKNECHT P. A. 2005. Basic Animal
Nutrition and Feeding. Animal Science Cornell University, New York. Pp 49-52
SAUVANT, D., PEREZ, J. M. and TRAN, G. 2004. Table of Composition and Nutritional
Value of feeds materials. Wageningen Academic, Netherlands. Pp 26-27
VILLAREAL, R. L. and GRIGGS, T. D. 1982. Sweet Potato. Proceeding of the First
International Symposium. Asian Vegetable Research and Development Center.
Shanhua, Tainan, Taiwan, China. P. 385.
YANG, T. H, TAI, Y. C. SHEN, H. S, KO, S. W, and BLACKWELL, R. O. 1975. Protein
content and its amino acid distribution of locally produced and sweet potato in
Taiwan. (in Chinese). 5. Chinese Agric. Chem. Soc. Pp 132 – 138.
Evaluation of Digestibility of Sweet Potato Meal in Swine
AGUSTIN, FERNAN B April 2012