Performance of pure and crossbred progenies of Red Sokoto and West African Dwarf goats in the Rainforest Zone of South Eastern Nigeria.

Abstract

This study is a report of part of a planned breeding programme to evaluate the performance of pure and crossbred progenies of Red Sokoto (RS) and West African Dwarf (WAD) goats in a rainforest zone of South Eastern Nigeria. A total of 56 kids produced by four breeding goat units consisting of pure Red Sokoto (RS x RS), pure West African Dwarf (WAD X WAD), main cross (RS x WAD), and reciprocal cross (WAD X RS) were used to investigate performance and cost benefit of producing progenies of these indigenous goats. The experimental design was a randomized complete block design with genetic group and sex as the factors of interest. Results showed that at birth, the male RS X RS kids weighed significantly (P<0.05) highest (1.84±0.23kg), followed by WAD X RS (1.43±0.14kg), RS X WAD (1.37±0.56kg) while the WAD X WAD kids had the lowest birth weight (1.15±0.39kg). However, the RS X WAD female kids, at birth weighed significantly highest (1.5±0.54kg), followed by the RS X RS (1.33±0.98kg), WAD X RS (1.31±0.17kg) and WAD X WAD (1.09±0.12kg).Body weight at 18 weeks was significantly higher for RS X RS (9.82±0.79kg) than the RS X WAD (8.34±0.85) which in turn was significantly higher than the WAD X RS (7.61±0.13kg) and WAD X WAD (7.51±0.61kg). The male and female kids of the RS X WAD had improved body weight and the linear body measurements namely, body length, height-at-withers and heart girth. This genetic group had a higher average daily gain (46.03 ± 1.41g/d) and better feed conversion ratio (5.38 ± 0.27) than the RS x WAD (6.64 ± 0.18) and WAD x WAD (7.02 ± 0.21). It also had the lowest cost of production (N953.40=$6.60) and as such the highest gross margin (N2,111.06 = $14.60) in 18 weeks. Individuals in this group appeared more promising hybrid goats for commercial meat goat production in the rainforest zone of South Eastern Nigeria.

Full text

Performance of pure and crossbred progenies of Red Sokoto and West African Dwarf goats in the
Rainforest Zone of South Eastern Nigeria.
1E. N. Nwachukwu, K. U. 2Amaefule, F. O. 3Ahamefule, S.C. 4Akomas, T. U. 5Nwabueze, U. A. U.
6Onyebinama and O. O. 6Ekumankama
1Department of Animal Breeding and Physiology, 2Department of Animal Nutrition and Forage Sciences,
3Department of Animal Production and Management, 4College of Veterinary Medicine, 5Department of
food Processing and Analysis, 6College of Agricultural Economics & Rural Sociology. Michael Okpara
University of Agriculture, Umudike, Umuahia, Abia State, Nigeria.
1Corresponding author; Email: ennwachuk@yahoo.com
Abstract
This study is a report of part of a planned breeding programme to evaluate the performance of pure
and crossbred progenies of Red Sokoto (RS) and West African Dwarf (WAD) goats in a rainforest
zone of South Eastern Nigeria. A total of 56 kids produced by four breeding goat units consisting of
pure Red So koto (RS x RS), pure West African Dwarf (WAD X WAD), main cross (RS x WAD), and
reciprocal cross (WAD X RS) were used to investigate performance and cost benefit of producing
progenies of t hese indigenous goats. The experimental design was a r andomized complete block
design with genetic group and sex as the factors of interest. Results showed that at birth, the male RS
X RS kids weighed significantly (P<0.05) highest (1.84±0.23kg), followed by WAD X RS
(1.43±0.14kg), RS X WAD (1.37±0.56kg) while the WAD X WAD kids had the lowest birth weight
(1.15±0.39kg). However, the RS X WAD female kids, at birth weighed significantly highest
(1.5±0.54kg), followed by the RS X RS (1.33±0.98kg), WAD X RS (1 .31±0.17kg) and WAD X WAD
(1.09±0.12kg).Body weight at 18 w eeks w as significantly higher for RS X RS (9.82±0.79kg) than the
RS X WAD (8.34±0.85) which in turn was significantly higher than the WAD X RS (7.61±0.13kg) and
WAD X WAD (7.51±0.61kg). The male and female kids of the RS X WAD had improved body weight
and the linear body measurements namely, body length, height-at-withers and heart girth. This
genetic group had a higher average daily gain (46.03 ± 1.41g/d) and better feed conversion ratio
(5.38 ± 0.27) than the RS x WAD (6.64 ± 0.18) and WAD x WAD (7.02 ± 0.21). It also had the lowest
cost of production (N953.40=$6.60) and as such the highest gross margin (N2,111.06 = $14.60) in 18
weeks. Individuals in this group appeared more promising hybrid goats for commercial meat goat
production in the rainforest zone of South Eastern Nigeria.
Key words: Red Sokoto and WAD goats, crossbreeding, linear body measurements, cost benefit,
rainforest zone.
Introduction
Goats constitute a very important part of the
rural economy in Nigeria, with more than
95% of the rural households keeping goats
(Ukpabi, et al., 2000; Otuma and Osakwe,
2008). As a multipurpose animal, goats
provide meat, milk, hides and skin and
manure. They rank next to cattle in income
generation and their meat (chevon) is quite
popular and well relished (Ladele, et al.,
1996; Hamayun, et al., 2006).
The need to develop productive and
adaptive goat breed for the rainforest zone
is desirable. Multiplication and distribution
of such high quality hybrid goat definitely
would increase small ruminant animal
production and animal protein supply in
South East and South-South Nigeria; where
the level of livestock production is quite
low. These geopolitical zones correspond to
the agro-ecological area described as the
rainforest zone where Tse-tse fly infestation
and typanosomiasis infection are serious
menace to livestock production. The use of
© 2012 Ni gerian Society for Animal Production Nigerian Journal of Animal Production
41
Vol. 39(II)

well adapted West African Dwarf (WAD)
and highly productive indigenous Red
Sokoto (RS) goat in 'new breed' formation
is an appropriate breeding plan especially
from the view point of utilizing local
animal genetic resources (AnGR) in
realizing local needs (Nwosu, 2005).
It is a common knowledge that not every
mating scheme yields satisfactory result
(Lamb, et al., 1992). To overcome some
suspected growth and r eproductive
problems associated with crossbreeding in
goats e.g. low birth weight, poor kids
survival rate, insufficient milk supply to the
young and dystocia (Malik et al; 1980);
mating of unproductive local males to
improved productive females has been
suggested in sheep (Dickerson, 1992).
Mating of WAD goats with Red Sokoto
breed has been carried out to determine
growth and reproductive potentials of the
offsprings (Taiwo, et al., 2005). Result of
that study revealed that present breeding
plan would be feasible and beneficial. The
objective of this study was therefore, to
evaluate growth performance and cost
benefit of producing pure and crossbred
lines of meat goats in a rainforest zone of
Nigeria.
Materials and methods
Location of study
This study was conducted at the goat Unit of
the Teaching and Research Farm of Michael
Okp a r a University of A griculture,
Umudike, Abia State, Nigeria. The study
area lies within the rainforest zone of South
East Nigeria with a bimodal rainfall pattern.
Total annual rainfall ranges from 1700 –
o
2100mm with a temperature range of 27 –
o
38 C during the dry season (November –
o o
April) and 18 – 26 C during the rainy
season (May – October). This agro-
ecological zone is a warm-wet humid
tropical environment.
Management of breeding stock
A total of 34 mature goats with an average
age of 10 months and consisting of 16 West
African Dwarf (WAD) and 18 Red Sokoto
(RS) goats constituted the breeding stock.
They were housed in a conventional dwarf
walled pen structured house. The sex ratio
was 1:8 for the WAD and 3:6 for the RS.
The animals were quarantined for 28 days
during which vaccination against pest des
pe t it ru minant (PPR) dise a se wa s
administered.
The breeding stock was maintained on a
daily feed allowance of 25% concentrate
ration and 75% fresh fodder made up of
Panicum maximum and a mixture of other
browse plants. The composition of the
Table 1: Percentage Composition of concentrate ration fed to breeding goats
Feed Ingredients Percentage
Maize offal 50.00
Wheat offal 6.50
Palm kernel cake 39.00
Bone meal 2.00
Periwinkle 1.00
Minerals
– vitamin premix 0.25
Salt 1.25
Total 100
% Crude protein (%) 13.9
ME (kcal/kg) 2980
Pe rfor ma nce of pur e an d cross b red proge nies of goats
42

concentrate ration fed to breeding WAD
and RS goats is shown in Table 1.
Mating Scheme
Mating schemes adopted to generate
progenies for the study were pure line, main
cross and reciprocal crossing as shown
below:
Pure line mating - RS X RS
- WAD X WAD
Main crossing - RS x WAD
Reciprocal
crossing - WAD X RS
Management of pure and crossbred kids
A total of 56 kids were produced by the
breeding stock. Kids were allowed with
their dams in nursing pens for 4 months
before weaning. Apart from a feeding
allowance of 300g/doe/day, additional
150g/kid/day was added for the number of
kids each doe nursed. Protection against
ecto- and endo-parasites among kids was
achieved using injectable Ivomectin
ad minis tered subc utane ously, whi le
vaccination against PPR disease was
carried out at 3 months of age.
Data collection
Data collected on pure and crossbred kids
were weekly body weight changes, body
length, heart girth and height-at-withers in
both sexes as well as scrotal circumference
in the buck kids only. The body length was
measured as the distance from the pole of
the animal to the base of the tail. Heart girth
was taken as the circumference of the chest
close to the forelegs, while height-at-
withers was measured as the distance from
the withers to the base of the hoof while the
animal stood erect on a platform. The
scrotal length was taken as the distance
from the base of the scrotum to the tip of the
scrotal sac, while the scrotal circumference
was measured as the region of largest
scrotal expansion. All linear body
measurements were taken with a tailor's
tape in centimeters.
Cost-benefit of raising each genetic group
was computed based on feed consumed,
other variable costs and prevailing market
price of life goats in the area. Average daily
gain (ADG) and feed conversion ratio
(FCR) of the various breeding groups were
also computed.
Experimental design and data analysis
The experimental design was randomized
complete block design with genetic group
and sex as factors of interest.
Y = u + G + S +e
ijk i J ijk
th th
Where Y = j individual in the i genetic
ijk
group
U = Overall mean
th
G = Effect of the i genetic
i
group (i = 1,--,4)
th
S = Effect of the j sex (1,2) in
ij
th
the i genetic group
e = Random error assumed to
jik
b e i n d e p e n d e n t l y
identical and normally
dis t r i b u ted with z e r o
m e a n a n d c o n s t a nt
variance.
Means and their associated standard
deviations were computed for the measured
parameters. Significant means were
separated using Duncan's New Multiple
Range Test (Duncan,1955).
Results and Discussion
The performance of male and female
progenies of pure and crossbred Red
Sokoto and West African dwarf goats are
presented in Tables 2 and 3, respectively.
Birth weight of the male kids was
significantly (P<0.05) highest for the RS X
RS (1.84 ±0.23kg), followed by WAD X RS
kids (1.43 ±0.14kg); RS X WAD (1.37
±0.57kg) while the WAD X WAD kids had
the lowest birth weight (1.15 ±0.39kg). This
Nwachuk wu, Amaefule, Ahamefule, Akomas, Nwabueze, Onyebinama and Ekumankama
43

observation was expected especially
between the two pure lines (RS x RS and
WAD X WAD) kids since such difference in
body weight is common knowledge and
underscores the need for the upgrading
programme. The RS X RS kids maintained
their superiority in body weight and were
only equaled by the RS X WAD kids. This
indicates obvious improvement in body
weight following crossbreeding for the RS
X WAD i n d i v i d u a l s . Si g n i fi ca nt
improvement in body weight and linear
body parameters in half bred RS X WAD
goats have been reported by Ozoje and
Herbert (1997) and in crossbred sheep by
Weiner and Hayter (1974) and Hassen et al.,
(2004).
The linear body measurements namely;
body length, height-at-withers, heart girth,
scrotal length and scrotal circumference
followed similar pattern as body weight in
the various genetic groups. This indicated
strong influence of body weight on these
structural body components. Indeed, strong
and positive associations between body
weight and most conformation traits have
been well reported in farm animal species
like goats (Ozoje and Herbert, 1997),
Ayrshire cattle, (Russel, 1975) and
humpless indigenous cattle (Ibe and
Table 2: Mean body weight and linear body measurements of male progenies of pure and crossbred
Red Sokoto and West African Dwarf goats.
PARAMETER
GENETIC GROUP
RS X RS RS X WAD WAD X RS WAD X WAD
Body Wt @ birth (kg) 1.84±0.23a 1.37±0.56b 1.43±0.14b 1.15±0.35b
Body Wt @ Wk 18(kg) 9.82±0.79a 8.34±0.85b 7.61±0.13cd 7 .51±0.61d
Body Length (cm) 67.60±3.07a 59.86±0.10b 57.16±1.19b 57.02±0.75b
Height at withers (cm) 52.72±2.28a 46.16±0.94b 42.86±0.76c 40.24±0.76c
Heart girth (cm) 53.20±1.45a 47.26±1.91ab 47.30±1.62b 46.98±2.16b
Scrotal length (cm) 8.82 ± 0.29a 7.53 ± 0.31a 6.97 ± 0.43ab 5.85 ± 0.27b
Scrotal circumf. (cm) 17.08 ± 1.74a 16.05 ± 1.52a 13.83 ± 1.62b 12.55 ± 1.02c
ab c Means on the same row bearing different superscripts are significantly different (P<0.05)
Table 3: Mean body weight and linear body measurements of female progenies of pure and
crossbred Red Sokoto and West African Dwarf Goats.
a b c Means on the same row bearing different superscripts are significantly different (P<0.05)
PARAMETER
GENETIC GROUP
RS X RS RS X WAD WAD X RS WAD X WAD
Body Wt @ birth (kg) 1.33±0.98b 1.50±0.54a 1.31±0.72b 1.09±0.11c
Body Wt @ Wk 18(kg) 6.88±0.85a 7 .64±0.52a 5.24±0.37b 5.11±0.31b
Body Length (cm) 58.85±3.00b 56.35±1.00a 53.65±0.25ab 50.10±1.14b
Height at withers (cm) 51.38±2.78a 44.55 ±0.36b 42.38 ±0.75b 42.25 ±0.60b
Heart girth (cm) 44.78±2.02a 42.45±0.34ab 41.33 ±0.81b 39.28 ±0.36b
Pe rforma nce of p ure and crossb red progeni es of go ats
44

Ezekwe, 1994).
The performance of the female kids (Table
3) revealed that the main crossbred (RS X
WAD) doe- kids had significantly higher
birth weight (1.50 ±0.54kg) than the RS x
R S ( 1 . 3 3 ± 0 . 98 k g ) , WA D x R S
(1.3 1 ± 0.7 2 k g) and WAD x WAD
(1.09±0.11kg). Birth weight of a kid is a
reproductive trait that could be influenced
by such factors as body weight and
condition score of dam, nutritional status,
type of birth, sex and season of the year
(Cassard et al., 1956). The WAD dams were
well adapted to the rearing environment and
may have utilized the concentrate – fodder
based ration better than their RS dam
counterparts. It could also be that the Red
Sokoto bucks mated to the WAD does were
able to stamp their superior genetic merits
on their female progenies, thus resulting in
the RS X WAD doe kids showing obvious
improvement in body weight even above
the RS X RS pure line. This superior-parent
improvement in body weight in the females
is desirable and is indeed, the essence of
crossbreeding (Shrestha and Fahmy, 2007).
Body weight attained by the pure and
crossbred lines at 18 weeks (Table 3)
showed that the RS x RS and RS x WAD
female goats were not significantly
different. However, the RS X WAD
individuals had numerically higher final
body weight (7.64±0.52kg) than even the
RS X RS females (6.88 ±0.85kg). The WAD
goat is a known meat animal (Jean, 1993)
and with improvement in its body weight,
both male and female hybrid WAD
progenies could grow fast and mature early.
This finding holds a good prospect for the
RS X WAD hybrids and presents them as
possible candidates for meat goats
especially in the rainforest zone which is a
natural habitat for the West African Dwarf
goats.
The performance of the WAD X RS hybrid
males (Table 2) and females (Table 3) is
noteworthy. This genetic group did not
differ significantly in final body weight
from the WAD X WAD individuals. This
result indicates that there was no obvious
improvement in body weight for both male
and female WAD X RS kids. The practical
Table 4: Average daily gain (ADG), feed conversion ratio (FCR), cost of production (CP), revenue
(R) and gross margin (GM) realized from pure and crossbred progenies of Red Sokoto
and West African Dwarf goats.
a, b, c Means on the same row bearing different superscripts are significantly different (P<0.05)
PARAMETER
GENETIC GROUP
RS X RS RS X WAD WAD X RS WAD X WAD
ADG (g/d) 45.37±1.34b 46.03±1.41a 43.45±3.34b 38.62±3.04c
FCR 7.97±0.15a 5.38±0.27b 6.64±0.18b 7.02±0.21a
CP (N) 1,392.16±13.64a 953.40± 10.21c 1,110.76± 12.32ab 1,032.00±10.25b
R ( N) 3,280.00± 24.01a 3,064.00±20.43b 2,930.00±26.01b 2,556.00±19.06c
GM ( N ) 1,888.00±13.22b 2,111.06±21.71a 1,819.24±15.01b 1,523.57±18.74c
Nwachuk wu, Amaefule, Ahamefule, Akomas, Nwabueze, Onyebinama and Ekumankama
45

implication of this finding is that the use of
Red Sokoto does mated to WAD bucks to
imp r o ve a goat h e r d coul d g i ve
disappointing results.
The production and economic performance
indices of raising pure and crossbred
progenies of Red Sokoto and West African
dwarf goats are presented in Table 4.
Average daily gain of 46.03 ± 1.41g/day at
126 days (18 weeks) achieved by the RS X
WAD was higher than that of the RS X RS
individuals (45.37 ± 1.34g/day) and this,
perhaps must have precipitated the higher
final body weight attained especially by the
female kids of this genotype (see Table 3).
This result indicated that the RS X WAD
crossbreds were well adapted to the
nutrition and rearing environment they
were subjected to, when compared to their
supposedly superior RS X RS counterparts.
The ADG value of 37g/day recorded for
half bred WAD X RS goats fed legumes and
fodders with concentrate supplementation
for 150 days at Ibadan (Ebozoje, 1992) was
even poorer than the value achieved by the
RS X WAD hybrid individuals in this study.
This seems to confirm further that these
main crossbred progenies were the most
preferred and suitable genotype for the
production environment
The feed conversion ratio (FCR) was
significantly low and more efficient for the
RS X WAD with a value of 5.38 ± 0.27
which however was not significantly
different from a value of 6.64 ± 0.18
obtained for WAD X RS. FCR was
significantly better for the hybrids when
compared to the RS X RS and WAD X
WAD pure lines which had FCRs of 7.97 ±
0.15 and 7.02±0.21, respectively at 18
weeks of age. Efficient feed conversion of
the RS X WAD in particular showed that the
upgrading exercise was effective and, of
course with improved weight gain- appetite
and feed intake were expected to increase
for this genotype. This finding showed that
the RS X WAD individuals were able to
utilize the local feed resources more
efficiently than their purebred counterparts.
This potential of the RS X WAD individuals
is desirable since good growth rate and
efficient feed utilization are common
attributes of good meat animals (Roge,
1992).
The RS X WAD hybrids which recorded the
highest ADG and a better FCR also had
significantly (P<0.05) the least cost of
production (N953.40 = $6.60) at 18 weeks
of age. This observation is understandable,
since these animals converted much of their
feed into flesh thus, resulting in higher final
body weight. Gross margin which is an
index of efficient production was also
highest (N2,111.06 = $14.60) for the main
cr o s sbred in dividual s . Th e overal l
performance of this genetic group suggests
that it is a promising genotype for the
development of hybrid meat goat especially
in the rainforest zone.
Conclusion
It is evident from the results of this study
that the progenies of the main crossbred
(RS X WAD) - males and females showed
superiority in body weight and in most of
the linear body measurements studied when
compared to the reciprocal (WAD X RS)
crossbreds. Average daily gain, feed
conversion ratio, revenue and gross margin
were all higher for the RS X WAD
individuals compared to their reciprocal
(WAD X RS) and pure (WAD X WAD)
counterparts. The performance of these
main crossbreds equaled those of the
superior RS X RS individuals and seems to
suggests that they are more promising goat
genotype for the production of hybrid meat
goat in the rainforest zone of South Eastern
Nigeria.
Pe rforma nce of p ure and crossb red progeni es of go ats
46

Acknowledgement
The authors are grateful to the Directorate
of Research and Development, Michael
Okp a r a University of A griculture,
Umudike for supporting this research work
through Research Grant No. API/07/05 of
2007. We are also grateful to the staff of
Goat Unit of the University who assisted in
the daily care of the experimental animals.
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Received: 26th August, 2011
Accepted: 5th May, 2012