| dc.description | INTRODUCTION
Animal protein intake in developing countries including
Tanzania has been very low compared to the
recommended level (Delgado et al., 1998 cited by
Pedersen, 2002; Nielsen et al., 2003). Local chickens
*Corresponding author. E-mail: jlwelamira@yahoo.com. Tel.:
+255-26-2302147; Fax: +255-26-2302147.
have high potential to offset this problem of low protein
intake compared to most other livestock species due to
their short generation intervals and their ability to survive
in harsh environments (Pedersen, 2002; Acamovic et al.,
2005; Muchadeyi et al., 2005). They are also raised by
majority of the rural households. Despite of these advan tages, local chickens have been associated with low
productivity owing to their inherent low genetic potential
(Katule, 1990; Pedersen, 2002). Various crossbreeding
844 Afr. J. Agric. Res.
programs between local chickens and improved (exotic)
chickens had been initiated in an attempt to combine
desirable features from these two diverse genetic groups
(that is, high productivity from exotic genotypes and high
adaptability from local chicken genotypes) (Katule, 1990).
However, such programs became unsustainable due to
unreliable supply and high costs of acquiring and
maintaining exotic breeding cocks, reduced broodiness
and ability to evade predation by the crossbred birds and
incompatibility of genotypes with farmers’ breeding
objectives and production systems (Tadelle et al., 2000;
Udo et al., 2001; Kosgey, 2004; Njega, 2005). Given their
low generation interval, selection within ecotype/breed
could successful bring about genetic improvement within
a reasonable time. In order to optimise selection res ponse, adequate characterisation of existing ecotypes is
important. Moreover, there is however, scanty information
available for most of the performance traits for Tanzania
local chickens. Results from random sampling of mature
birds from villages done in a previous studies in Tanzania
indicated Kuchi ecotype to be superior to other ecotypes
in terms of body weight and egg weight and it was even
recommended for meat production, and converse was
true for Medium ecotype (Lawrence, 1998; Msoffe et al.,
2001; Msoffe, 2003). However, no systematic study has
been carried out to evaluate their average body weights
at different ages under different management systems
and egg production traits. Therefore, this study was
carried out with the aim of evaluating these traits in the
two chicken ecotypes.
MATERIALS AND METHODS
Study site, experimental materials and their management
This study was carried out at Sokoine University of Agriculture
(SUA) poultry research unit, Morogoro, Tanzania and two nearby
villages (that is, Kauzeni and Mgambazi). The place is located at an
altitude of about 525 m, above sea level. The relative humidity at
the location is about 81%, while the monthly mean and maximum
temperatures are 18.7 and 30.1
oC, respectively. The area has an
annual mean rainfall of 846 mm. Experimental chicks were derived
from two parent stocks, one representing Kuchi ecotype obtained
from drier parts of north west Tanzania, and another representing
Tanzania Medium (Medium) ecotype obtained from central part of
the country.
Hatching and management of experimental materials for on station trial
A total of 1468 chicks were produced in eleven hatches for on station trial (intensive management) at the University farm with 645
and 823 chicks being from Kuchi and Medium ecotypes, produced
from 163 and 175 hens, respectively. Hatched chicks were tagged
and housed in floor pens up to 12 weeks of age. Thereafter, they
were transferred to individual cages.
Birds were fed a starter ration (20% CP and 2800 Kcal ME/kg)
from day old to 8
th week of age, growers ration (16% CP and 2750
Kcal ME/kg) from 9
th
to 16
th week of age, and layers ration (17% CP
and 2700 Kcal ME/kg) from 17
th week of the age to the rest of the
period. Parent stock was also fed the same layers ration. Water
was supplied on ad libitum basis. Birds were also vaccinated
routinely against Gumboro and Newcastle disease (ND).
Hatching and management of experimental materials for on farm trial
After the end of mating and hatching period in on-station
experiment, the parent stock was taken to the field for on-farm
experiment. The study involved two villages viz. Kauzeni and
Mgambazi. A total of 285 hens from the two ecotypes (139 and 146
hens from Medium and Kuchi ecotypes, respectively), and 46 cocks
(22 cocks being from Kuchi, and 24 cocks being from Medium
ecotype) were supplied to 68 farmers, that is, 30 and 38 farmers
from Mgambazi and Kauzeni, respectively. Criteria for the choice of
the farmers were based on the willingness of a farmers to
participate in construction of a chicken house, which could
accommodate at least 6 adult birds on individual compartments,
and to participate in a training (a three day training) on how
experimental birds should be managed and willing to adopt that
management system. The building materials for construction of
chicken houses were supplied by the Enhancement of Health and
Productivity of Smallholder Livestock in East Africa (PHSL) project.
A farmer only contributed a space for building a chicken house
around his/her homestead and labour.
Parent stocks were vaccinated against ND and Gumboro two
weeks and one week, respectively before being taken to the field.
Initially each farmer was supplied with two hens from each ecotype
(4 hens per farmer), however due to fertility problems some farmers
(few) were given up to 5 hens. Upon arrival to the field, hens were
placed in individual compartments and mated to cocks of their own
ecotypes while in individual compartments (that is, hens were not
allowed to go out to meet with other hens/ unplanned cocks). Three
to four nearby farmers were supplied with two cocks one from each
ecotype and these farmers were sharing these cocks for mating
their hens. Each farmer was staying with a breeding cock for 3 to 4
days and passes it on to another farmer. Furthermore, hens were
also let to lay, incubate and hatch their eggs while in individual
compartments. Confinement of hens in individual compartments
during mating up to hatching was done to avoid mix-up of cocks.
This was done with the help of field supervisors (two field
supervisors per village). Tasks of field supervisors were recording,
medication, vaccination, tagging of birds, that is, newly hatched
chicks and ensuring that birds are managed by farmers according
the protocol of the experiment.
During mating, incubation and hatching periods, birds were
supplied with water and layers ration (17% CP and 2700 Kcal
ME/kg) on ad libitum basis. At this period parent stocks were also
given antihelmintics (Kukuzole
®
) and broad spectrum antibiotics
(OTC-plus
®
) regularly (prophylactic treatments) according to
manufacturer instructions, and their bodies/houses were dusted
with pesticides (Dudu-dust
®
) to control external parasites. Feeds
and medications were supplied by the project. After hatching chicks
were tagged and hens continued to stay in confinement with their
chicks for a period of ten days. While in confinement the birds were
fed chick starter as that used in on-station trial. The purpose of
confining chicks in the early days of their lives was to minimize
mortalities due to predation. After the end of confinement period
birds were freed and chicks left to move out (scavenging) with their
mothers. At this stage birds were depending entirely on scavenging
feed. A total of 554 and 690 chicks from Kuchi and Medium
ecotypes were hatched. Due to fertility problems, not all hens
supplied to farmers possessed chicks. Therefore the above chicks
were progeny of 101 and 112 hens for Kuchi and Medium ecotype,
respectively. The vaccination regimes for chicks were as in the on station trial.
Lwelamira et al. 845
Table 1. Analyses of variances: F-values for body weights at various ages.
SoV Bwt8 Bwt12 Bwt16 Bwt20
On-station Hatch 5.9*** 4.5*** 3.7*** 3.2***
Ecotype 375.4*** 1249.6*** 1484.9*** 1208.6***
Sex 545.7*** 734.2*** 390.9*** 446.2***
Hatch*Ecotype 2.8** 1.9 1.1 1.2
Hatch*Sex 0.8 1.1 0.8 0.7
Ecotype*Sex 0.3 0.0 0.2 1.1
R-square 0.66 0.70 0.68 0.74
On- farm
Farm 2.2*** 1.5*** 1.9*** 1.9***
Season 2.1* 11.5*** 10.6*** 7.9**
Ecotype 130.5*** 129.3*** 160.0*** 175.4***
Sex 78.9*** 144.1*** 144.7*** 154.4***
Season*Ecotype 3.5 3.1 4.5 3.3
Season*Sex 2.3 2.6 2.6 0.7
Ecotype*Sex 2.7 0.2 1.0 0.5
R-square 0.57 0.55 0.59 0.64
SoV = Source of Variation; Bwt8, Bwt12, Bwt16, and Bwt20 = Body weights at 8, 12,
16, and 20 weeks of age, respectively. *, **, *** = Significant at (P < 0.05), (P < 0.01),
and (P < 0.001), respectively.
Traits measured
Body weights were recorded on all individual chicks at 8, 12, 16 and
20 weeks of age. For the on-station trial, hens were further
assessed for age at sexual maturity, egg production, egg weight,
shell thickness and egg shape index. Age at sexual maturity was
measured by age at first egg in days, and egg production by
number of eggs during the first 90 days from sexual maturity. Egg
weight, shell thickness and egg shape index was recorded on each
individual hen as the average of 3 to 4 eggs from 33
rd
to 36
th weeks
of age. A micrometer screw gauge was used to measure shell
thickness. In each egg, shell thickness was recorded as the
average of three readings taken from three different sites on the
egg, that is, at the equator (middle), broad and narrow ends as it
has been suggested in previous studies (Khatkar et al., 1994;
Mohammed et al., 2005). Egg shape index was measured
according to Chen et al. (1993) and Smith (2001) as the ratio of egg
width to length (in %). A vernier calliper was used to measure egg
width and length. Mortality was also recorded in the entire
experimental period.
Statistical analyses
All data were checked for skewness using SAS (2000)
UNIVARIATE procedure and found to conform to normal
distribution. The data were then subjected to descriptive statistical
analyses and least squares analyses of variances using the SAS
(2000). General Linear Models (GLM) procedure using statistical
models 1 and 2 for on-station and on-farm body weights
respectively were employed. Statistical model 3 was used for egg
production traits from the on-station trial. The models are shown
below:-
Yijkl = + Hi + Gj + Ck+ (HG)ij + (HC)ik + (GC)jk + eijkl………Model 1
Where: Yijkl = observation of l
th
individual from k
th
sex, j
th
ecotype
and i
th
hatch;
= overall mean; Hi = fixed effect of i
th
hatch (i = 1..11); Gj = fixed
effect of j
th
ecotype (j = 1..2); Ck = fixed effect of k
th
sex (k = 1..2);
(HG)ij = interaction between hatch and ecotype; (HC)ik = interaction
between hatch and sex; (GC)jk = interaction between ecotype and
sex; eijkl = random effect peculiar to each individual distributed as
N(0, 0, I e
2
).
Yijklm = + Fi + Pj+ Gk + Cl + (PG)jk + (PC)il + (GC)kl + eijklm…Model 2
Where: Yijklm = observation of m
th
individual from l
th
sex, k
th
ecotype,
j
th
hatching season and i
th
farm; = overall mean; Fi = fixed effect of
i
th
farm (i = 1..65); Pj = fixed effect of j
th
hatching season (j = 1..2);
Gk = fixed effect of k
th
ecotype (k = 1..2); Cl = fixed effect of l
th
sex (l
= 1..2); (PG)jk = Interaction between season and ecotype; (PC)il =
Interaction between season and sex; (GC)kl = Interaction between
ecotype and sex; eijklm = random effect peculiar to each individual
distributed as N(0, I e
2
).
Yijk= + Hi + Gj + (HG)ij + eijk ……………………….Model 3
Where: Yijk = observation of k
th
individual from j
th
ecotype and i
th
hatch; = overall mean; Hi = fixed effect of i
th
hatch (i = 1..11); Gj =
fixed effect of j
th
ecotype (j = 1..2); (HG)ij = interaction between
hatch and ecotype; eijk = random effect peculiar to each individual
distributed as N(0, I e
2
).
RESULTS AND DISCUSSION
Body weights at various ages
Least squares analyses of variances for body weights at
various ages are presented in Table 1. Least squares
846 Afr. J. Agric. Res.
Table 2. Body weights under intensive management (on-station) summarized by sex and ecotype.
Kuchi Medium
N Lsmeans ± s.e Range N
Lsmeans ±
s.e Range
M Bwt8 (g) 279 540.7 ± 3.2 280-748 368 457.4 ± 2.3 231-615
Bwt12 (g) 278 1025.6± 5.8 701-1460 365 845.5 ± 4.5 586-1175
Bwt16 (g) 274 1448.5± 6.1 1035-2060 360 1240.2 ± 4.9 991-1720
Bwt20 (g) 270 1706.2± 6.9 1295-2318 360 1512.0±6.1 1186-2040
F Bwt8 (g) 317 438.4 ± 2.5 242-662 395 350.1 ± 1.9 202-545
Bwt12 (g) 315 883.2 ± 5.6 655-1316 393 705.6 ± 3.5 478-1013
Bwt16 (g) 312 1339.2 ± 5.9 1048-1804 391 1124.9± 4.3 836-1634
Bwt20 (g) 310 1586.8±6.2 1296-2053 388 1382.1± 4.6 1070-1906
M+F Bwt8 (g) 596 489.6 ± 2.3 242-748 763 403.7 ± 1.7 202-615
Bwt12 (g) 593 954.4 ± 4.1 655-1460 758 775.6 ± 3.2 478-1175
Bwt16 (g) 586 1393.9 ± 4.5 1035-2060 751 1182.5 ± 3.5 836-1720
Bwt20 (g) 580 1646.5 ± 4.9 1295-2318 748 1447.1 ± 4.4 1070-2040
M, F and M+F= Males, females and both males and females, respectively; Bwt8, Bwt12, Bwt16, and Bwt20 = Body
weights at 8, 12, 16, and 20 weeks of age, respectively.
Table 3. Body weights under extensive management (on-farm) summarized by sex and ecotype.
Kuchi Medium
N Lsmeans ± s.e Range N Lsmeans ± s.e Range
M Bwt8 (g) 201 374.9±3.9 190-518 248 305.0±3.0 178-421
Bwt12 (g) 195 739.1±7.4 470-987 238 630.1±5.8 450-864
Bwt16 (g) 190 1023.5±9.4 735-1329 230 897.2±7.4 752-1253
Bwt20 (g) 186 1240.2±10.2 902-1567 215 1097.5±9.4 858-1419
F Bwt8 (g) 203 320.1±3.5 180-509 266 240.9±2.4 171-407
Bwt12 (g) 197 631.7±7.2 454-920 254 531.0±4.7 425-831
Bwt16 (g) 192 924.5±8.3 731-1281 244 793.60±6.0 697-1226
Bwt20 (g) 187 1135.2±9.6 870-1470 223 994.10±8.0 817-1406
M+F Bwt8 (g) 404 347.5±2.8 180-518 514 273.0±2.0 171-421
Bwt12 (g) 392 685.4±5.3 454-987 492 580.5±3.7 425-864
Bwt16 (g) 382 974.0±6.4 731-1329 474 845.4±5.2 697-1253
Bwt20 (g) 373 1187.7±7.3 870-1567 438 1045.8±6.8 817-1419
M, F and M+F = Males, females and both males and females, respectively; Bwt8, Bwt12, Bwt16, and Bwt20 = Body
weights at 8, 12, 16, and 20 weeks of age, respectively.
means along with their standard errors are presented in
Tables 2 and 3. Results from analyses of variances
indicate that there was a significant effect of hatch, sex
and ecotype on body weights under intensive
management (P < 0.001). Furthermore, most of the
interactions between these main effects were not
significant (P > 0.05). Under extensive management
system, body weights were also significantly influenced
by ecotype and sex (P < 0.001). In addition, effect of farm
and hatching season were also significant (P < 0.01).
Effect of various interactions between main effects
included in the statistical model was not significant (P >
0.05).
Results show that Kuchi was heavier than Medium
ecotype under both management systems. Body weights
for Medium ecotype were around 80 to 89% of that of
Kuchi under both management systems, and there was a
significant reduction (of 24 to 27%) in body weights in
both ecotypes under extensive management system. Low
body weights under extensive management could be
attributed to hash environment (that is, feed shortages,
high prevalence of diseases and parasites) that is usually
prevailing under such a system (Magwisha et al., 2002;
Hørning et al., 2003; Rosa dos Anjos, 2005).
The superiority of Kuchi over Medium ecotype in terms
of body weight demonstrated in the present study
supports the results of a previous study by Lawrence
(1998) done in random samples of mature birds from
villages, in which mean mature body weights for Kuchi
and Medium ecotypes were reported to be 2708 and
1850 g for males, and 1828 and 1108 g for females,
respectively. For body weights at 8 weeks of age under
intensive management, results of the present study are
higher than those below 400 g, averaged over both sexes
reported for local chickens of Nigeria (Adedokun and
Sonaiya, 2001; Fayeye et al., 2005) and Ethiopia
(Demeke, 2003). Slightly higher values (600 g) were
reported by Segura-Correa et al. (2004) in Mexican
(Creole) local chickens. Concerning body weights at 12
weeks of age under intensive management, the mean
weight for Kuchi obtained in the present study (954 g)
over both sexes is close to the average weight of 973 g
by Ramlah (1996) in Malaysian local chickens, but higher
than the reported figures of 775 g (Manjeli et al., 2003),
around 600 g (Nwosu et al., 1984; Adedokun and
Sonaiya, 2001) and 375 to 510 g (Tadelle et al., 2003) for
local chickens of Cameroon, Nigeria, and Ethiopia,
respectively. The value for Medium ecotype is in the
middle of the above range. At 16 weeks of age under
intensive management, the overall mean body weights
for Kuchi and Medium ecotypes of 1394 and 1183 g,
respectively are somewhat higher than the mean weight
of 802 g (Nwosu et al., 1984) obtained for local chickens
of Nigeria. On the other hand, the value for Medium
ecotype is close to the lower end of the range (1136 to
1520 g) reported for local chickens of Thailand and
Malaysia (Theerachai et al., 2003), and some strains of
South African local chickens (ARC, 2005), while that of
Kuchi is in the middle of this range. Average body weight
at 20 weeks in the current study for both sexes in Kuchi
under intensive management is in agreement with the
range (1600 to 2000 g) obtained for South African local
chickens by ARC (2005). For Medium ecotype, the
present results are not dissimilar to the average body
weight at 20 weeks of age under intensive management
reported for Vietnamese local chickens, which varied
from 1300 to 1500 g (FAO, 2005). Further, the current
body weight for Medium ecotype agrees closely with the
findings by Demeke (2003) of 1300 g in Ethiopian local
chickens.
Quite a number of studies have also reported the
performance of local chicken under extensive
management. With regard to average body weight at 8
weeks of age, a value of 197 g (Demeke, 2003) and 187
g (Tadelle and Ogle, 1998 cited by Tadelle et al., 2003)
averaged over both sexes were reported for Ethiopian
local chickens. These values are lower than the current
observations in both ecotypes. On the other hand,
Pedersen (2002) and Sandra (2005), working
independently both reported a mean weight of 250 g for
Zimbabwean and Malawian local chickens, which is close
to the current finding for Medium ecotype (273 g) but
somewhat lower than the value obtained for Kuchi (348 g).
Lwelamira et al. 847
Concerning body weights of local chicken at later ages
under extensive management, apart from mature body
weight, relatively few studies have reported average body
weights at more than 8 weeks of age. Average body
weights at 12 weeks of age regardless of sex were
reported to be 631 and 640 g in Burkina Faso (Sall, 1990
cited by Sonaiya and Swan, 2004) and in Zimbabwean
local chickens (Pedersen, 2002), respectively. These
values are in between the weights for Kuchi (685 g) and
Medium (581 g) ecotypes obtained in the present study.
On the other hand, weights obtained by Sall (1990) cited
by Sonaiya and Swan (2004) (of 860 g), and Pedersen
(2002) (around 1000 g) for body weight at 16 weeks of
age were close to corresponding weights for Medium
(845 g) and Kuchi (974 g) ecotypes.
Regarding average body weights at 20 weeks of age,
the values of 1300 g (Ramlah and Shukor, 1987) for
Malaysian, and around 1000 g (Pedersen, 2002) for
Zimbabwean local chickens under extensive manage ment tend to concur with the current findings for Kuchi
(1188 g) and Medium ecotype (1046 g), respectively.
Although Kuchi had higher body weights than Medium
ecotype, their weights are not far from those reported in
the literature clearly indicating that local chickens in
developing countries have poor growth rate when
compared to the improved stocks. It can also be
discerned that generally local chickens can be marketed
at body weights of around 1 kg and above (Pedersen,
2002; Theerachai et al., 2003; Acamovic et al., 2005)
which in both ecotypes and sexes could be attained at
about 16 and 20 weeks of age under intensive and exten sive management systems, respectively. This implies that
market weight in the studied local chicken populations is
attained at rather late ages compared to 8 weeks of age
for meat type chickens, and 12 weeks for the crosses
between local chickens and meat type chickens (Ali et al.,
2000; Pedersen, 2002; Theerachai et al., 2003) under
intensive management. Marketable body weight for these
ecotypes could probably be further improved to enhance
market value, or let them to be attained at earlier age
following genetic improvement through selection. How ever this will depend on the existence of substantial
additive genetic variation in these populations with regard
to body weight. The Kuchi would be a better ecotype to
start with in this endeavour because of their higher body
weight compared to Medium ecotype.
Egg production traits
Results from analyses of variance (Table 4) indicate the
existence of significant differences between ecotypes
with respect to age at sexual maturity (P < 0.01), egg
number (P < 0.05), and egg weight (P < 0.01).
Differences between ecotypes with regard to shell
thickness and egg shape index were not significant (P >
0.05). The effect of hatch in most of the above traits was
848 Afr. J. Agric. Res.
Table 4. Analysis of variance: F-values for egg production and
related traits.
SoV AFE EN-90 EW STH ESI
Hatch 1.0 1.4 0.8 1.3 1.9*
Ecotype 7.6** 4.6* 6.8** 0.0 0.3
Hatch x Ecotype 1.1 1.5 0.7 1.9 1.1
R-square 0.67 0.66 0.69 0.58 0.66
SoV = Source of Variation; AFE = Age at first egg (Days); EN-90 = Egg
number in the first 90 days after sexual maturity; EW = Egg weight (g);
STH = Egg shell thickness (µ); ESI = Egg shape index (%). *, ** =
Significant at (P < 0.05) and (P < 0.01), respectively
was not significant (P > 0.05).
Results from Table 5 show that Medium ecotype tended
to attain sexual maturity 5 days earlier than Kuchi (173
days vs 168 days), however, findings from both ecotypes
are still within the range of 153 to 203 days reported in
literature for unimproved local chickens in other countries
(Choprakarn et al., 1998; Adedokun and Sonaiya, 2001;
Demeke, 2003; Khalil et al., 2004). Despite the fact that
Medium ecotype matured earlier than Kuchi, its average
egg weight was noticeably lower than that of Kuchi (42 g
vs 45 g). Compared to the previous studies, the value
obtained in Medium ecotype for egg weight is very close
to those of around 40 g given by Fayeye et al. (2005),
Pedersen (2002) and Islam et al. (2001) for local
chickens of Nigeria, Zimbabwe and Bangladesh, respect tively, but lower than the value of around 49 g reported by
Chen et al. (1993) in Taiwan local chickens. On the other
hand, the average egg weight for Kuchi of 45 g obtained
in the present study falls in the middle of the range
reported in these previous studies.
Average egg number in the first 90 days of laying was
significantly higher in Medium ecotype than in Kuchi (49
vs 45). These figures correspond to laying intensities of
54 and 50% for Medium ecotype and Kuchi, respectively.
Katule and Mgheni (1990) and Khalil et al. (2004) working
with some chicken ecotypes of Tanzania and Saudi
Arabia, respectively both reported egg number in similar
periods of laying that corresponded to a slightly higher
laying intensity of around 58%. However, the current
values in both ecotypes are within the range of 40 to 55%
derived for local chickens of Sudan (Mohammed et al.,
2005), Nigeria (Adedokun and Sonaiya, 2001), and
Thailand (Choprakarn et al., 1998).
Analyses of variance revealed no significant differences
between ecotypes with respect to eggshell thickness and
egg shape index. The average egg shape indices for
Kuchi and Medium ecotype were 75 and 74%, res pectively. These values are within the range of 72 to
80% reported by Njega (2005) for some Kenyan chicken
ecotypes, and Khan et al. (2004) for crosses between
Bangladesh local chickens and RIR and Fayoumi, but
higher than the value of 58% given by Fayeye et al.
(2005) for Nigerian local chickens. Average shell thick thickness in both ecotypes in this study was around 37 µ.
The value is on the upper side of the range (34 to 37 µ)
reported for Sudanese local chickens (Arad and Malder,
1982; Mohammed et al., 2005), and very close to the
value of 38 µ presented by Chen et al. (1993) in Taiwan
local chickens. The values for average shell thickness
and egg shape index obtained for both ecotypes in this
study were also within the range recommended in litera ture by several authors (Bao, 1978 cited by Khang and
Ogle, 2004; Eshwaraish, 1988 cited by Ali, 2002; Smith,
2001; Mohammed et al., 2005). Since shell thickness and
egg shape index have been shown to be optimal,
selection programmes geared at improving genetic
potential for egg production traits in the studied ecotypes
should be based on improving egg number, egg weight
and age at sexual maturity. However, as with body
weight, this will depends on the existence of substantial
additive genetic variation for these traits in the two
ecotypes for selection to be effective. In this case the
Medium ecotype could be a good material to start with
because it is somewhat superior to Kuchi with respect to
these traits.
Mortalities
Results from Table 6 show that percent survivals up to 12
weeks of age were 91.9 and 70.8% for Kuchi, and 92.1
and 71.3% for Medium ecotype under intensive and
extensive management systems, respectively. This
corresponds to percent loss of about 8.1 and 29.2% for
Kuchi, and 7.9 and 28.7% for Medium ecotype, res pectively, indicating high mortality rate in both ecotypes
under extensive management compared to intensive
management. Differences between ecotypes in both
management systems were not significant (P > 0.05).
Causes of chick loss under extensive management were
mainly diseases (42%) and predators (33%), while under
intensive management system, apart from diseases
(36%), cannibalism mainly at the age of 4 weeks and
above also contributed a significant loss of 29% (Figure 1
and 2). Visible disease symptoms before chicks died
under extensive management system were mainly
swollen head, lesions in the head, diarrhoea (gastroin testinal problems), emaciation/weakening, and sometimes
respiratory signs, while under intensive management it was
mainly diarrhea (gastrointestinal pro-blems). Further more, a few chicks from extensive management system
were sampled for further laboratory analysis at SUA and
some of them were found to have worms.
Compared to the previous studies, the percent
loss/mortalities under intensive management are within
the range (0 to 24%) reported in literature (Nwosu et al.,
1984; Pedersen, 2002; Demeke, 2003; Tadelle et al.,
2003; Lwelamira and Katule, 2004). Regarding the values
under extensive management, despite of the confinement
of the chicks in the first ten days of their lives in the
current experiment, percent loss/mortality rate were only
Lwelamira et al. 849
Table 5. Egg production and related traits (Lsmeans ± s.e) summarized by ecotype.
Ecotype Trait Lsmeans ± S.E Minimum Maximum
Age at sexual Maturity (N = 300)
Kuchi Age at first egg (Days) 173.2 ± 0.8 142 236
Egg number and egg quality (N = 296)
Egg Number (90-Days) 44.5 ± 0.5 23 78
Egg weight (g) 45.0 ± 0.2 35 54
Shell thickeness (µ) 37.3 ± 0.2 30 55
Egg shape index (%) 74.8 ± 0.3 68 86
Age at sexual maturity (N = 381)
Medium Age at first egg (Days) 167.92 ± 0.7 145 232
Egg number and egg quality (N = 373)
Egg Number (90-Days) 48.9 ± 0.5 31 77
Egg weight (g) 42.4 ± 0.2 34 53
Shell thickeness (µ) 37.3 ± 0.2 32 54
Egg shape index (%) 74.1 ± 0.3 65 85
Table 6. Cumulative survival/ mortalities up to 12 weeks of age summarized by management system and ecotype.
Management Ecotype N No. Died/Lost % Died/lost
No.
Survived
% Survived
2
- Value
Intensive Kuchi 645 52 8.1 593 91.9 0.04
NS
Medium 823 65 7.9 758 92.1
Extensive Kuchi 554 162 29.2 392 70.8 0.28
NS
Medium 690 198 28.7 492 71.3
NS = Non-sigificant (P > 0.05).
36
18
7
29
10
0
5
10
15
20
25
30
35
40
%
oftotal loss
Diseases Hatched
weak
Deformed Cannibalism Accident
Causes
Figure 1. Causes of chick loss under on-station management.
850 Afr. J. Agric. Res.
42
33
4
2
4
9
6
0
5
10
15
20
25
30
35
40
45
% of total loss
Diseases Accident External
parasites
Unknown
Causes
Figure 2. Causes of chick loss under on-farm management.
reduced by a small margin when compared to some other
previous studies. For example, mortality rate up to 12
weeks of age under extensive management without early
confinement of birds were reported to be 45% for
Zimbabwean local chickens (Pedersen, 2002), and 41%
for Botswana local chicks (Mushi et al., 2005) compared
to the values close to 30% obtained in the current
experiment under the same age. This could pose a threat
to breeding programmes under extensive management.
Hence, confinement of chicks for a bit longer period
before being released to the field and regular disease
control regimes seem to be required.
Conclusion
From the results of the present study it can be concluded
that Kuchi was superior to Medium ecotype in terms of
body weights and converse was true for age at sexual
maturity (that is, age at first egg) and egg number.
However, their performance can further be improved by
improving both management system and improving their
genetic potential through within ecotype selection. Since
Kuchi ecotype was superior to Medium ecotype in terms
of body weights and opposite was true for Medium
ecotype in terms of most egg production and related
traits. Therefore, Kuchi ecotype could be good starting
genetic material for further improvement in body weight,
and Medium ecotype in egg production traits.
ACKNOWLEDGEMENT
This study was part of Ph.D work of the senior author.
Financial support of DANIDA through PHSL project at
Sokoine University of Agriculture is highly acknowledged.
REFERENCES
Acamovic T, Sinurat A, Natarajan A, Anitha K, Chandrasekaran D,
Shindey D, Sparks N, Oduguwa O, Mupeta B, Kitaly A (2005).
Poultry. In: Livestock and Wealth Creation. Improving the husbandry
of animals kept by resource-poor people in developing countries.
(Edited by Owen, E., Kitaly, A., Jayasuriya, N. and Smith, T).
Nottingham University press, UK, pp. 304- 324.
Adedokun SA, Sonaiya EB (2001). Comparison of the performance of
Nigerian indigenous chickens from three agro-ecological zones.
Livestock Research for Rural Development 13(2):
[http://www.cipav.org.co/lrrd/lrrd13/2/aded 123.htm].
Ali KO, Katule AM, Syrstad O (2000). Genotype x environmental
interaction in growing chickens: comparison of four genetic groups on
two rearing systems under tropical conditions. Acta Agric. Scand. 50:
65-71.
Ali S (2002). Study on the effect of feed supplementation to laying hen
under the rural condition of Bangladesh. M.Sc. Dissertation, The
Royal Veterinary and Agrucultural University (RVAU), Copenhagen,
Denmark, p. 210.
Arad Z, Malder J (1982). Differences in shell-quality among Sinai
Bedouin fowl, commercial White Leghorn and their crosses. British
Poultry Sci. 23: 107-112.
ARC (2005). Agriculture research council- South Africa. Fowl for Africa.
[http://www.arc.agric.za/institute/aii/main/division/animbreedgen/reso
urcepo /fowlsfa.htm]. Site visited on 18/8/2005.
Chen CF, Lee YP, Lee ZH, Huang SY, Huang HH (1993). Heritabilities
and genetic correlations of egg quality traits in Taiwan’s local
chicken. Asian- Aust. J. of Animal Sci. 6(3): 433-440.
Choprakarn K, Salangam I, Tanaka K (1998). Laying performance, egg
characterisitics and egg compositions in Thai indigenous hens. J.
National Research Council of Thailand 30(2): 1-17.
Demeke S (2003). Growth performance and survival of Local and White
Leghorn chickens under scavenging and intensive systems of
management in Ethiopia. Livestock Research for Rural Development.
15(11): [http://www.cipav.org.co /lrrd/lrrd15/2/deme1511.htm].
FAO (2005). Village Poutry production in Vietnam. The Bangladesh
model and other experiences in family poultry development.
[http://www.fao.org/ag/againfo/ subjects/en/infpd/documents
/econf_bang/asia2.html.].
Fayeye TR, Adeshiyan AB, Olugbami AA (2005). Egg trait, hatchability
and early growth performance of the Fulani-ecotype chicken.
Livestock Research for Rural Development 17 (8):
[http://www.cipav.org.co/lrrd/lrrd17/8/faye170 94.htm].
Hørning G, Rasmussen S, Permin A, Bisgaard M (2003). Investigations
on the Influence of Helminth Parasites on Vaccination of Chickens
against Newcastle Disease Virus under Village Conditions. Trop.
Anim. Hlth and Prod. 35(5): 415 – 424.
Islam MA, Bulbul SM, Seeland G, Islam ABMM (2001). Egg quality of
different chicken genotypes in summer and winter. Pakistan J. of Biol.
Sci. 4 (11): 1411-1414.
Katule AM (1990). Studies on prospects of improving the performance
of the local chicken population in Tanzania by crossbreeding .PhD
Dissertation, Sokoine University of Agriculture, Morogoro, Tanzania.
p.180.
Katule AM, Mgheni M (1990). Performance of crosses between exotic
and local Tanzania chickens. In: Proceedings of the 4
th World
Congress on Genetics Applied to Livestock Production. Edinburgh,
16: 62- 64.
Khalil MK, Al-Homidan AH, Hermes IH (2004). Crossbreeding
components in age at first egg and egg production for crossing Saudi
chickens with White Leghorns. Livestock Research for Rural
Development 16(1): [http://www.cipav .org.co/lrrd/lrrd16/8/Kha
l161.htm].
Khan MKI, Khatun MJ, Kibria AKMG (2004). Study on the quality of
eggs of different genotypes of chickens under semi-scavenging
system in Bangladesh. Pakistan J. of Biol. Sci. 7(12): 2163-2166.
Khang NTK, Ogle B (2004). Effect of duckweed on the performance of
local (Tau vang) laying hens. Livestock Research for Rural
Development 16(8): [http:// www.cipav.org.c /lrrd/lrrd16/8/khan
16057. htm].
Khatkar MS, Sandhu JS, Brah GS, Chaudhary ML (1994). Genetic
analysis of egg shell quality characters in layer chicken. Indian J. of
Anim. Sci. 64:1248-1253.
Kosgey IS (2004). Breeding objectives and breeding strategies for small
ruminants in the tropics. PhD Dissertation, Wageningen University,
Wageningen, The Netherlands. p. 272.
Lawrence P (1998). Ecotypes and natural disease resistance among
scavenging local chickens of Tanzania. M.Sc. Dissertation. The
Royal Veterinary and Agricultural University (RVAU), Copenhagen,
Denmark. p. 97.
Lwelamira J, Katule AM (2004).Genetic determination of immune
responses to Newcastle disease virus vaccine in chickens. Bulletin
Anim. Hlth and Prod. in Africa 52: 186 – 197.
Magwisha HB, Kassuku AA, Kyvsgaard NC, Permin A (2002). A
comparison of the prevalence and burdens of helminth infections in
growers and adult free-range chickens. Trop. Anim. Health Prod.
34(3): 205 – 214.
Manjeli Y, Tchouboue J, Teguia A (2003). Heritability of body weights in
local chickens of Cameroon. J. of the Cameroon Academy of Sci.
3(2):76-80.
Mohammed MD, Abdalsalam YI, Kheir AM, Jin-yu W, Hussein MH
(2005). Comparison of egg characteristics of different Sudanese
Indigenous chicken types. Intern. J. of Poultry Sci. 4(7): 455-457.
Msoffe PLM (2003). Diversity among local chicken ecotypes in
Tanzania. PhD Dissertation. Sokoine University of Agriculture,
Morogoro, Tanzania, p. 223.
Msoffe PLM, Minga UM, Olsen JE, Yongolo MGS, Juul-Madsen HR,
Gwakisa PS, Mtambo MMA (2001). Phenotypes including
immunocompetence in scavenging local chicken ecotypes in
Tanzania. Trop. Anim. Hlth and Prod. 33(4): 341-354.
Lwelamira et al. 851
Muchadeyi FC, Sibanda S, Kusina NT, Kusina JF, Makuza SM (2005).
Village chicken flock dynamics and contribution of chickens to
household livelihoods in smallholder farming area in Zimbabwe. Trop.
Anim. Hlth and Prod. 37(4): 333-344.
Mushi EZ, Binta MG, Chabo RB, Seipone B (2005). Chick mortality in
indigenous chickens (Gallus domesticus) under free range
management in Sebele, Gaborone, Botswana. J. Animal and
Veterinary Advances 4(9): 768-770.
Nielsen H, Roos N, Thilsted SH (2003). The impact of semi-scavenging
poultry production on the consumption of animal source food by
women and girls in Bangladesh. J. Nutrit. 133: 4028-4030.
Njega SM (2005). Productivity and socio-cultural aspects of local poultry
phenotypes in Coastal Kenya. M.Sc. Dessertation. The Royal
Veterinary and Agricultural University (RVAU), Copenhagen,
Denmark. p. 79.
Nwosu CC, Obioha FC, Omeje SS, Gowen F, Bellonwu CT, Onuora GI
(1984). Growth performance of chickens in deep litter systems. Wld
Rev. Anim. Prod. 20 (2): 17-26.
Pedersen CV (2002). Productivity of semi- scavenging chickens in
Zimbabwe. PhD Dissertation. The Royal Veterinary and Agricultural
University (RVAU), Copenhagen, Denmark.
Ramlah H, Shukor MN (1987). Malaysia: production systems. In:
Newcastle disease in poultry. A new food pellet vaccine. J. W.
Copland, ed. ACIAR Monograph Canberra, Australia, 5: 86–88.
Ramlah H (1996). Performance of village fowl in Malaysia. Wld Poultry
Sci. J. 52: 75-79.
Rosa dos Anjos F (2005). Effect of scavenging feed resource base on
prevalence of parasites and performance of chickens in
Sussundenga District, Mozambique. M.Sc. Dissertation. The Royal
Veterinary and Agricultural University (RVAU), Copenhagen,
Denmark. p. 81.
Sandra MJAG (2005). The impact of improved housing and early
nutrition on the productivity of local chickens in Mozambique. M.Sc.
Dissertation. Royal Veterinary and Agricultural University (RVAU).
Copenhagen, Denmark. p. 75.
Segura-Correa JC, Sarmiento-Franco L, Maga a-Monforte JG, Santos Ricalde R (2004). Productive performance of Creole chickens and
their crosses raised under semi-intensive management conditions in
Yucatan, Mexico. British Poultry Sc. 45 (3): 342-345.
Smith AJ (2001). Poultry. The Tropical Agriculturalist. Revised edition.
Macmillan Education LTD. London and Oxford.
Sonaiya E and Swan SEJ 2004. FAO Animal Production and Health 1.
Manual. Small Scale Poultry Production. Technical guide.
[ftp://www.ftp.fao.org/008/ y5169e/y5161e00.pdf.]
Statistical Analysis System SAS (2000). SAS/STAT Users' Guide,
Release 6.12 Edition, SAS Institute Inc, Cary, North Carolina. USA.
Tadelle D, Alemu Y, Peters KJ (2000). Indigenous chickens in Ethiopia:
genetic potential and attempts at improvement. Wld Poultry Sci. J.
56: 45-54.
Tadelle D, Kijora C, Peters KJ (2003). Indigenous chicken ecotypes in
Ethiopia: Growth and feed utilization potentials. Internat. J. of Poultry
Sci. 2(2): 144-152.
Theerachai H, Ezzat T, Michael Z (2003). Options for native Chicken
(Gallus domesticus) production in Northeastern Thailand. In:
Proceedings of the conference on International Agricultural Research
for Development. Göttingen, Germany. [htt://www.tropentag.de
/2003/abstract/full /166.pdf].
Udo HMJ, Asgedom AH, Viets TC (2001). Modelling the impact of
interventions in village poultry systems. In: Livestock Community and
Environment. Proceedings of the 10th Conference of the Association
of Institutions for Tropical Veterinary Medicine. 21-22 August 2001,
Copenhagen, Denmark, [http://www.aitvm.kvl.dk/C_poultry
/C13Udo.htm | en_US |
