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J. Trop. Resour. Sustain. Sci.
6 (2018)
: 88-92
88
eISSN Number: 2462-2389
© 2018
UMK Publisher. All rights reserved.
Nutrient composition of Blaptica dubia (Order: Blattodea) as an alternative protein
source
Lam Pei Yee1, Nurul Syaza Abdul Latif 1, Kumara Thevan1,*, Paspuleti Visweswara Rao2, Wan Zahari Wan
Muhamed3
1Faculty of Agro-Based Industry, Universiti Malaysia Kelantan, Locked Bag No.100, 17600 Jeli, Kelantan, Malaysia.
2Institute of Food Security & Sustainable Agriculture, Universiti Malaysia Kelantan, 17600 Jeli, Kelantan, Malaysia.
3Faculty of Veterinary Medicine, Universiti Malaysia Kelantan, Locked Bag No.36, 16100 Pengkalan Chepa, Kota Bharu, Kelantan,
Malaysia.
Received 7 February 2018
Accepted 26 May 2018
Online 17 December 2018
K
eywords:
Blaptica dubia, animal, feed,
protein, livestock
⌧
*Corresponding a
uthor:
Dr. Kumara Thevan,
Faculty of Agro Based Industry,
Universiti Malaysia Kelantan,
Locked Bag No.100, 17600 Jeli,
Kelantan, Malaysia
Email: thevan@umk.edu.my
Abstract
Blaptica dubia is a cockroach that used as feed for most reptiles and amphibians because of it
nutritive value. Its alternative protein sources can replace the current high priced imported animal
feed such as fishmeal, soybeans and meat. It has potential as an animal feed and minimize high
livestock farming cost of the farmers. A study was conducted to determine the nutritional
composition (moisture, ash, crude protein, chitin and fat) of B. dubia in different growth stages.
Moisture and ash determine using AOAC protocol, protein using Kjeldahl method, chitin using
chemical treatment and fat analysis using soxhlet extraction method. The proximate analysis of
adults and nymph of B. dubia contained 59.06-62.70% moisture, 2.47-4.17% ash, 47.50-54.32%
crude protein, 3.83-5.58 % chitin and 35.49-44.22% fat on dry weight. Thus, the tested feed pellets
could be an alternative protein source as the animal feed especially in pet industry.
©
2018 UMK Publisher
. All
rights reserved.
1. INTRODUCTION
In 2050, the world population is predicted to reach
9 billion people and minimum 70% risen of global
harvested yields are required to provide sufficient food
sources (Finley & Seiber, 2014). The increasing world
population bring up the issues of food insecurity due to the
production of food sources are unable to support for human
and livestock consumption. Sustainable food and feed
sources are needed to produce adequate food supply
continuously for the growing population. Insects will be a
newly alternative choice. Entomophagy which means
insects eating is becoming economic importance for feed
and food sources due to the nutritive components, low
costing and the fast reproduction rate of the insects
(Anankware et al., 2015).
Insects can be used as food because of its absolute
protein levels and protein quality (Yi et al., 2013). Insects
give a high food conversion efficiency when compared
with conventional livestock due to its shorter life cycle.
The production of protein sources from insects will cause
less environmental effects than the breeding of livestock,
which producing greenhouse gas and ammonia emissions.
Thus, the culturing of insects can be introduced as a
sustainable farming of protein production.
Dubia cockroach (Blaptica dubia) also known as
South-American Dubia cockroach and Orange-spotted
cockroach, is a large, sexually dimorphic blaberid
cockroach. The wings are fully developed in the males
adults but they have a poor development of arolium
between their claws which make them unable to climb on
smooth surfaces; neither nymph nor adult stages (Wu et al.,
2013). This species is reared as feed for most of the reptiles
and amphibians. Blaptica dubia consists of higher protein
content compared to other insect sources such as crickets
which are commonly used. Its rearing method is easy to be
maintained with minimum smell compared to other
cockroaches. Low-technique is required in rearing the
insects as they are easily feed on organic waste materials
and convert it into protein (van Huis et al., 2013).
Dubia cockroach can be a good alternative source
of protein with less environmental impact, short life cycle
and able to be reared in a huge production. Malaysia is a
tropical country which provides a suitable climate in term
of temperature and humidity for the breeding of Dubia
cockroach. However, far too little attention has been paid
to culture and convert its protein content into animal feed
in this country. In this scenario, our aim is to determine the
nutrient composition of B. dubia at adults and nymph
stages.
J. Trop. Resour. Sustain. Sci.
6 (2018)
: 88-92
89
eISSN Number: 2462-2389
© 2018
UMK Publisher. All rights reserved.
2. MATERIALS AND METHODS
2.1. Rearing
Blaptica dubia colonies were reared at a mean
room temperature of 26.16 ± 2.5˚C with about 75.34 ±
6.98% of relative humidity. They were maintained in the
plastics box [35(h) x45(w) x60(l) cm]. The plastics boxes
were covered with netted lids (Ø ≈ 2mm) to provide air
circulation for the colony. The egg cardboards were
provided and stacked horizontally inside the plastics box to
act as shelter, hiding and breeding sides. The colonies were
supplied with kitchen waste and water sources in the
corners directly on the container floor.
2.2. Nutrition analysis
Blaptica dubia which are adult male, adult female
and nymph (Figure 1) were sampled and analysed for
moisture, ash, protein, chitin and fat content. The moisture
content was determined by drying 2g sample at 135°C for
two hours (AOAC, 2005b; Undersander, et al., 1993). The
ash content was determined by burning 5g sample in a
muffle furnace at 550°C for three hours (AOAC, 2005a).
Analysis of protein content was done using Kjeldahl
method (FOSS, 2003). Chitin extraction was using
chemical treatment method suggested by Majtán et al.
(2007). Soxhlet extraction method was used to analyse fat
content (Anderson, 2004). All of the analysis conducted for
five replicates.
Figure 1: Appearance of Blaptica dubia. (a) Female adult, (b)
Male adult, (c) Nymph
2.3. Statistical analysis
One-way analysis of variance (ANOVA) was
used to measure the significance of the differences
between the nutrient contents in nymph and adult stages of
B. dubia. All statistical test was performed using SPSS
(IBM SPSS Statistics Version 22). For graphical
representation of nutritional value, a radar chart was
develop using Microsft Excel 2012.
3. RESULTS AND DISCUSSION
Table 1 shows the proximate nutrient composition
of B. dubia for male, female and nymph that determined on
dry matter basis. Male had the higher moisture content of
62.70% while nymph had the lower moisture content
which is 59.06%. The study found that no significant
difference in the moisture content between male, female
and nymph (p-values >0.05).
The result in Table 1 show higher ash content
(4.17%) in male compared with female and nymph which
are 3.69% and 2.47%, respectively. However, significant
difference was found in between ash content of male,
female and nymph (F(2,12) = 3012.665, p = .000).
Male consist of the highest protein content which
was 54.32% follow by female (52.87%) and the least in
nymph which was 47.50% (Table 1 & Fig. 2). The protein
content in male showed significant difference compare
with female and nymph of B. dubia though(F(2,12) = 37.984,
p = .000). However, no significant difference was found in
between female and nymph (post hoc Tukey test, p =
0.227).
Table 1: Proximate nutrient composition of Blaptica dubia in
male, female and nymph.
Moisture
(%)
Ash
(%)*
Protein
(%)*
Chitin
(%)*
Fat
(%)*
Male
62.70 ±
1.08ª
4.17 ±
0.03ª
54.32 ±
2.00ª
4.38 ±
0.79ª
35.51 ±
0.71ª
Female
61.46 ±
3.45ª
3.69 ±
0.05ᵇ
52.87 ±
1.01ᵇ
5.58 ±
0.23ª
35.49 ±
3.68ª
Nymph
59.06 ±
1.00ª
2.47 ±
0.02ᶜ
47.50 ±
0.23ᵇ
3.83 ±
0.36ᵇ
44.22 ±
1.05ᵇ
Result represent the Mean ± SD of the five estimations.
*The percentage of Ash, Protein, Chitin and Fat are based on the dry
basis of the sample.
a b c represents the significant different (p<0.05) of respective
composition among the male, female and nymph.
Figure 2: Radar chart of nutritional value of B. dubia according
to the male, female and nymph.
The chitin content observed in female was 5.58%
which was higher than male (4.38%) and nymph (3.83%).
There are significant difference of chitin value among the
adults and nymph(F(2,12) = 14.961, p = .001). .
The nymph had high amount of fat (44.22%) than
male and female which were similar of 35%. Significant
difference was found in fat content between male to nymph
and female to nymph.
Insects are being used for its multiple purposes,
such as human food and animal feeds as an alternative
nutritional sources. Blaptica dubia is increasing popularity
among western countries to use as feeder insects for
J. Trop. Resour. Sustain. Sci.
6 (2018)
: 88-92
90
eISSN Number: 2462-2389
© 2018
UMK Publisher. All rights reserved.
reptiles and amphibians or even able to act as additive
value for broiler chicken feeds as stated by Bildan et al.
(2012). The nutritive value in cockroach can be act as
healthy food and feed materials, also the food safety
evaluation have confirmed that cockroach is not poisonous
to animals and human Feng et al. (2014).
The ranges of moisture content of B. dubia in this
study were similar with the moisture of Argentinean
cockroach (59.63%) and American cockroach (61.30%) as
stated by Young (2010). The moisture content found in the
study also match with the general moisture presented in
raw insects (55 to 85%) and low moisture content in whole
insects usually indicated high fat composition (Finke,
2008). Similarly, the nymph of B. dubia shown lower
moisture content when compare with adults but highest
value of crude fat. The moisture content found in other
insects are 3.63% in adult Holotrichia parallela (beetle)
(Yang et al., 2014) and 56.82% in Rhychophorus
phoenicus (weevil) (Amadi et al., 2014). Higher moisture
content may increase the microbial activities and caused
deterioration during storage (Siulapwa et al., 2014).
The lower of ash content in B. dubia was
indicated that there was lacking of minerals it contains
which lower than other insects like the larva of Cirina
forda (10.26 ± 0.01%) that considered minerals-rich insect
(Omotoso, 2006). Ash content of B. dubia in this study also
lower than the great minerals source of cricket
(Brachytrupes membranaceus) that consist of 6.4% (Paiko
et al., 2013).
Significant difference found in protein value
between B. dubia adults (male and female) and nymph
stage is due to the adult has high crude protein content
(54.32% and 52.87%) than the nymph (47.50%). Bigger
sized adults have form harden cuticle than the smaller
nymph stage which have a less nitrogenous soft cuticle.
The reason is the adult stages are covered with a nitrogen-
hydrogen bonded chitin layer that increase the N content in
the calculation of protein content (Pretorius, 2011), due to
the analysis method used (Kjeldahl method (FOSS, 2003)).
Besides, Mayer (2014) stated that adult insects of crickets,
houseflies, fruit flies, hissing cockroaches and Turkestan
cockroaches consist of higher protein content than the
juvenile cockroaches and nymph crickets. Mbah and
Elekima (2007) found that the Componotus sp. (carpenter
ants) could be used as feed in livestock supplement as it
consists of high crude protein (40.10%) whereby, B. dubia
probably is more suitable for the feed production due to a
higher protein content. Longvah et al., (2011) also
suggested that the protein content from defatted eri
silkworm (Samia ricinii) pupae was suitable to use as
animal nutrition in pet food or poultry industry.
When comparing to other protein sources
(Pretorius, 2011), the protein content of common housefly
(Musca domestica) larvae (60.38%), pupae meal (76.23%)
and fish meal (69.13) are higher than the B. dubia while
protein content in soya oil cake meal (49.44%) is slightly
lower. Blaptica dubia also has a higher protein content than
the long-horned grasshopper (Ruspolia differens) which
has a value of 37.1% for green coloured grasshopper and
35.3% for brown coloured grasshopper stated in Kinyuru
et al. (2011). Higher protein content are available in insects
when comparing to lean red meat sources of beef (23.2%),
veal (24.8%) and mutton (21.5%) (Kinyuru et al., 2011).
Although livestock by-products such as chicken offal
which consists of 65.8% crude protein are lower prices
than fish meals (Omole et al., 2008), this cheap protein
sources are lacking of essential biological values of amino
acids (Shariff & Mona, 2013). Therefore, B. dubia could
be used to replace the meat protein sources as it is easy to
maintain in the small area of farm because rearing of this
insects are inside the storage boxes that can be piled one
above another.
The result shown in Table 1 and Figure 2 was
against with Oonincx and Dierenfeld (2012) stated that
higher protein and lower fat content in nymph stage of
development as nymph had the least protein and highest fat
percentages when compared with the adult stage of the
same species. However, the protein content in male, female
and nymph of B. dubia still remain in the ranges of
cockroach species which was 38% to 76% dry matter that
stated in the literature (Oonincx & Dierenfeld, 2012).
Higher chitin contents were found in adults of B.
dubia than the nymph (3.83 ± 0.36%) but the female (5.58
± 0.23%) was higher than male (4.38 ± 0.79%) in this
study. However, the larval and pupal cuticles of the
tobacco hornworm (Manduca sexta) consist of higher
(14% and 25%) chitin content than the adult cuticles (7%)
(Kramer & Muthukrishnan, 2009). Lower chitin also was
found in B. dubia when compared with adult Holotrichia
parallela which was 10.47 ± 0.53% (Yang et al., 2014)
and 9.1% crude chitin from housefly larvae (Zhang et al.,
2011). Although high yield of chitin can get from
crustacean shells such as crab (13 to 26%), shrimp (14 to
42%) and krill (34 to 49%), the chitin extraction process
from them is expensive (Tajik et al., 2008; Zhang et al.,
2011). Thus, the chitin value available in insects can be
another alternative source for extraction.
The fats available in diets play important roles to
enhance the palatability of food, function of the cells and
transportation of the vitamins (Omotoso, 2006). The crude
fat content in nymph of the B. dubia was quite high, 44.22
± 1.05%, when compared with the adults. Higher crude fat
content also found in B. dubia when compared with
Argentinean cockroach (34.88%) and American cockroach
(28.4%) (Young, 2010). The nymph of B. dubia was
similar to six-spotted cockroach nymph (Eublaberus
distanti) in the past study of Oonincx and Dierenfeld
(2012) which had more fat value and less protein content
that could provide higher calorie as animal feed. Mayer
(2014) also stated that the juvenile stage of beetles and
J. Trop. Resour. Sustain. Sci.
6 (2018)
: 88-92
91
eISSN Number: 2462-2389
© 2018
UMK Publisher. All rights reserved.
cockroaches have higher fat value than the adult stage.
Since the nymphs are younger than adults, the higher fat
content in the nymph could be used as cheaper animal fat
and oil-based products from insects (Mbah & Elekima,
2007). However, the result in this study shown is
diversed from Yi et al. (2013) which stated that B. dubia
consist of 67.4 ± 2.1% moisture content, 19.3 ± 0.9% crude
protein and 7.7 ± 0.1% fat content. This might due to
different stages of B. dubia, segment of the insects’ body,
feeding materials and growing environment of the insect
will affect the composition of the analysis.
Digestibility is important to determine the
utilization of protein which provide the actual amount of
nutrients consumed and absorbed by the animals as poor
quality of protein and diets will give low digestibility
(Badina, 2012). Low quality of protein will cause poor
absorption in the animal and may influence health of the
animals (Shariff & Mona, 2013). According to Oonincx
and Dierenfeld (2012), the nutritional content that
available in insects are able to achieve the domestic
carnivores feeding requirements. However, the
invertebrate cuticle or exoskeleton of various insect consist
certain amount of chitin that can decrease the digestibility
of the whole insect diet (Arbuckle, 2009).
Generally, 80% or higher protein digestibility was
found in pet foods which will closely meet the amino acid
and protein quality required by the animals (Buffington,
1991). The apparent digestibility of B. dubia feed pellets
was consider high that having an average of 81.57%.
However, it was similar to the apparent crude protein
digestibility of high-protein extruded (81.6%) in cats but
lower than the raw beef-based and cooked beef-based diet
which were 93.3% and 92.9% Kerr et al. (2012). Schiavone
et al. (2014) suggested that Hermetia illucens and Tenebrio
molitor meals are suitable to use in feed for broiler chicken
as alternative protein source due to their significant values
of apparent digestibility of crude protein (69.1% and
66.1%). Finke (2008) indicated rats, chickens and fish
which were fed with insects, such as flies, crickets and
mealworms have been found to grow healthily due to the
good palatability and absent of anti-nutritional factor.
There is limited reports on the essential
requirement of amino acids, fatty acids and its composition
in the insects that could be use as feed (Oonincx &
Dierenfeld, 2012). Further research to be conducted to
identify the specific nutrients elements in B. dubia as the
additive value or alternative protein source that suitable for
animal consumption.
4. CONCLUSION
Dubia cockroaches were found to have higher
protein content when compared with other feeding sources.
This enables to support the growing demand of protein
sources for animal feed requirement. Insect farming has the
advantages of low costing and fast reproduction rate if
compared to animal livestock farming. Blaptica dubia also
easy to maintain than the shorter lifespan crickets rearing
that will make noise, smell and escape from the rearing
colonies easily. In fact, the manufacture of animal feed
from by-products of the livestock such as internal organs
and bones which consist of less amount of nutrients that
might not sufficient to support the diet of the rearing
animals. Besides, the halal issues on the animal feed also
being questionnaire on the sources of the raw materials.
Thus, it could be an alternative way to get another protein
sources to replace the livestock meat or by-products in
animal feed. Insects have been becoming more and more
economic important in other countries as they are more
profitable compared with imported feed or raw materials
that built up higher cost of production.
ACKNOWLEDGEMENT
We would like to thank Mr. Muhamad Faiz from
Faculty Veterinary Medicine Universiti Malaysia Kelantan
and Mr. Lee Yik Bing for their assistance throughout the
study period. We were grateful to Dr. Mohammad Mijanur
Rahman for his suggestions to further improve the
manuscript. We thank Ministry of Education of Malaysia
for financial support provided under grant
[R/FRGS/A07.00/00760A/004/2016/000366].
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