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Publication of the College of Agriculture and Environmental Sciences, Bahir Dar University 101
Research Article
Efficiency of the oestrus synchronization with hand mating and artificial insemination on
the reproductive performances of Woyto-Guji Goat under community-based breeding
program
Dereje Dea
1*
, Ermias Eramo
1
and Anwar Seid
2
1
Arba Minch Agricultural Research Center, Arba Minch, Ethiopia
2
Ethiopia Institute of Agricultural Research, Addis Ababa, Ethiopia
Corresponding author: deredea12@gmail.com
Received: December 29, 2022; Received in revised form: May 8, 2023; Accepted: May 13, 2023
Abstract: The present study was designed to describe the efficiency of oestrus synchronization on Woyto-Guji goats
under community-based breeding program in Konso zone. Single and double injections of PGF2α followed by AI
and single injection followed by buck mating were the protocols applied. Percent responded, inseminated,
conceived, delivered, aborted, time of insemination, gestation length and litter size were data collected for the
experiment. A total of 177 does were used for oestrus synchronization by using PGF2α hormone. Overall, the
findings revealed that about 88.14% of the does expressed oestrus within 57.48±2.64 hours after hormone
administration. The overall percent inseminated, conceived, delivered and aborted and gestation length (day) were
91.67, 93.71, 72.03, 2.82%, and 152.48±2.34, respectively. The overall percent of kid sex born was about 51%
female and 49% male, and litter size was about 58% single and 42% twin. The response rate was significantly
affected by age (P<0.05). Percent inseminated, conceived, kid delivered and time of insemination were significantly
affected by protocol, parity and age (P<0.05). Buck mating on hormone treated does was relatively easily
applicable for increased conception rate under the community level.
Keywords: Konso, Oestrus, Synchronization, Woyto-Guji Goat
This work is licensed under a Creative Commons Attribution 4.0 International License
1. Introduction
Animal breeding is improvement of a population
through the selection of the best individuals of the
current generation and using them as parents of the
next generation (Solomon, 2014). To be successful in
genetic improvement of livestock, appropriate
breeding programs need to be planned, implemented
and maintained. Small ruminant breeding programs
in tropical countries are less organized and largely
fragmented (Solomon et al., 2014). Many of the
programs were based on the upgrading of the
indigenous animal to exotic breeds. Most of the
crossbreeding activities were not successful and
sustainable due to incompatibility of the breeding
objectives and the management approaches of the
existing production system due to low owners’
participation, complicated in terms of logistics,
technology and infrastructure; indiscriminate
crossbreeding and lack of analysis of the different
socio-economic and cultural roles (Haile et al., 2009;
Ahmed, 2017, Dereje et al., 2019). Community-based
breeding program is a recently advocated option for
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tropical traditional low-input livestock production
systems (Gizaw et al., 2009; Haile et al., 2011;
Philipsson et al., 2011; Wurzinger et al., 2011). This
is because community-based breeding programs take
into account the indigenous knowledge of the
communities on breeding practices and breeding
objectives and also consider the production system
holistically and involve the local community at every
stage, from planning to operation of the breeding
program (Gizaw et al., 2013).
In Ethiopia, there are about 52.46 million goats
where almost all of them are indigenous breeds,
about 99.9 % (CSA, 2021). Woyto-Guji goat breed is
one of eight genetically characterized goat breeds
(Tesfaye, 2004) under the Rift-valley family
(Solomon et al., 2014) which are distributed
throughout the country. Despite the large population
of goats and the roles of goats at a household and
national level, the productivity and the contribution
of goats to the country economy is far below the
potential. Goat production in Ethiopia is constrained
by a lack of systematic breeding programs (Solomon,
2014).
Goats in temperate regions show reproductive
seasonality due to a photoperiod effect (Usman et al.,
2019). However, they show weak reproduction
seasonality in tropical conditions. Non-seasonal
breeding has the advantage of the continuous supply
of milk, meat and surplus kids to the producers.
However, low kid survival and growth happen if
pregnancy and birth fall during low forage
availability (Girma, 2009; Delgadillo, 2015). Oestrus
synchronization tackles such unwanted oestrus cycle
and oestrus length variability on goat reproduction
(Omontese et al., 2016) by fixing does breeding time
(Rahman et al., 2008).
Indigenous goats’ reproduction management in
tropics like Ethiopia can be improved by using
various simple natural manipulation (buck mating),
prostaglandins hormonal alteration and mixed
protocols (Omontese et al., 2016). However, the
choice of hormone and estrus synchronization
protocols depends on cost-effectiveness, ease of
application, and resultant fertility (Zeleke, 2015;
Bekahegn et al., 2022). In this regard, the efficiency
of oestrus synchronization protocols is not examined
for the Woyto-guji goat breed yet. Therefore, the
current study aimed to evaluate the efficiency of
oestrus synchronization protocols with hand mating
and artificial insemination on the reproductive
performance of indigenous goats under a community-
based goat breeding program.
2. Materials and Methods
2.1. Description of the study areas
The study was conducted in Baide community-based
breeding cooperative village from 2020 to 2021 in
Konso zone. Konso zone is located between the
latitude of 5
o
30 North and a longitude of 37
o
30 East.
Altitude ranges from 610 and 2,000 meter above sea
level. The zone is bordered on the south by the
Oromia Region, on the west by the Woyto River, on
the north by the Dirashe special woreda, on the
northeast by Amaro special woreda, and on the east
by Burji special woreda.
The rainfall in the zone is not reliable with 800 mm
per year. The majority of the rainfall is occurred in
the months ranging from March and April.
Temperature ranges from below 15 °C at night to 32
°C during the day. The main crops produced are
sorghum and Moringa stenopetala. Despite erratic
rainfall and poor soil fertility, the famous
traditional soil and water conservation measures
were practiced by the Konso people.
2.2. Sampling procedures
Breeding goats reared under a community-based
breeding program were used for the experiment. For
the effectiveness of the prostaglandin PGF2α
hormone on active corpus luteum (Kefyalew, 2015);
healthy, good body condition, cyclic and non-
pregnant does were selected for the experiment.
Pregnancy diagnosis was also conducted before
hormone administration by using Pregtone (field
ultrasound) to minimize abortion due to the PGF2α
hormone. Breeding bucks were also selected based
on their breeding soundness.
The synchronization agent used was prostaglandin-
based estrumate hormone (Cloprostenol sodium
1ml/0.263 mg), which was administered
intramuscularly at 1 ml dose, obtained from the South
Regional Government Agricultural Office.
Immediately after hormone administration, does were
randomly allocated either for the AI or to mate with
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selected bucks based on a 1:10 buck: does ratio. Two
weeks before and during the breeding period, the
breeding bucks were supplemented with concentrate
per day to maintain their body weight loss. Those
does showing heat signs were served with buck
within 96 hours (Hamed et al., 2012; Solomon et al.,
2016). Oestrous response to hormone administration
was determined based on expression of standing heat
when does were exposed to teaser bucks. Pregnancy
diagnosis was conducted by non-return to heat. Kids
were confirmed upon kidding records. Processed
fresh semen, artificial vagina, breeding bucks,
healthy breeding doe and prostaglandin PGF2α
hormone administered 1ml/doe were used for the
experiment.
2.3. Hormone administration protocols
Hormone protocols that were proposed by Gizaw et
al. (2016) were used in the present study as indicated
below.
Protocol 1: Single Injection of PGF2α hormone, heat
detection and AI within 72 hours
Protocol 2: Single Injection of PGF2α hormone, heat
detection and buck service within 72 hours
Protocol 3: Double Injection of PGF2α hormone at
11days interval, fixed AI at 48 hour post injection.
2.4. Data collection and analysis
Data collected for oestrus synchronization were the
total number of does treated with PGF2α hormone,
does responded, inseminated, conceived, delivered,
aborted, time of insemination, gestation length, litter
size and kid sex, protocol type, parity, and age by
dentition, body condition score by feeling the
backbone and the ribs with the thumb and fingertips
(Gerald, 1994).
The collected data were analyzed using SPSS
(version 20) and described by mean, standard
deviation and frequency (chi-square) where GLM
model was used for analysis [1].
Does responded, inseminated, conceived, delivered,
aborted, time of insemination, and gestation length
were considered as the response variables and
collected using the formula indicted below [2-10].
Protocol types, parity, age by dentition and body
condition scores were considered as fixed effects
(Tegegn and Zelalem, 2017).
[1]
Where;
Y
ijk
= the response variables
α = the intercept
A
i
= the fixed effect of protocol (1= Single shot
and AI, 2 = single shot and buck, and 3 =
double shot and fixed AI)
B
j
= the fixed effect of parity (1-5)
C
k
= the fixed effect of age (1-4 pairs of
permanent incisors)
e
ijk
= random error
[2]
ORR = Oestrus response rate
[3]
CR = Conception rate
[4]
KR = Kidding rate
[5]
RL = Reproduction loss
[6]
AR = Abortion rate
[7]
DDR = Does didn`t respond
[8]
DNI = Does not inseminated
[9]
DDC = Does didn’t conceived
[10]
DDDK = Does didn`t deliver kid
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3. Results and Discussion
3.1. Efficiency of the oestrus synchronization
A total of 177 does were used for oestrus
synchronization experiment. The overall percent of
the does expressed heat sign were about 88.14%
within 57.48±2.64 hours after hormone
administration (Table 1). The overall rate of does
inseminated, conceived, delivered and gestation
length (day) were about 91.67%, 93.71%, 72.03%
and 152.48±2.34 days, respectively. Except, for
gestation length the current findings were higher than
the results obtained under on-farm conditions for
Abergele goat breed (Bekahegn et al., 2022) for
single prostaglandin hormone administration. The use
of the “male effect” is reported to improve oestrus
efficiency and fertility when used in combination
with prostaglandins (Amarantidis et al., 2004).
Protocols did not significantly affect gestation length.
The current finding was in line with Girma (2009).
The overall abortion rate was about 2.82% (Figure 2).
The abortion rate was not significantly (P>0.05)
affected by protocol types, parity, and age. The low
rate of abortion could be due to early pregnancy
diagnosis by using Renco Corporation (2000) field
ultrasound before hormone injection.
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Table 1: Effect of hormone protocols, parity and age on performance of Woyto-Guji goat
Parameters
Does
injected
(N)
Does responded
(%)
Inseminated/mat
ed (%)
Conceived (%)
Kidding rate
(%)
Abortion rate
Time of
insemination (hour)
Gestation length (day)
Overall
177
156(88.14)
143(91.67)
134 (93.71)
103 (72.03)
5(2.82±1.23)
143 (57.48±2.64)
103 (152.48±2.34)
Protocols
NS
*
*
*
NS
*
NS
1
58
51 (87.93)
45 (88.23)
c
40 (88.89)
c
31 (68.89)
c
2 (3.48±1.22)
45 (63.20±3.5)
c
31 (152.12±2.41)
2
65
57 (87.69)
55 (96.49)
a
54 (98.18)
a
40 (72.73)
b
1(1.53±1.24)
55 (59.16±4.3)
b
40(153.11±1.98)
3
54
48 (88.89)
43 (89.58)
b
40(93.02)
b
32 (74.42)
a
2(3.70±1.23)
43(49.12±0.11)
a
32(152.22±2.64)
Parity
NS
*
*
*
NS
NS
NS
1
35
31 (88.57)
28 (90.32)
c
26(92.86)
b
19(67.86)
c
1(2.86±1.22)
31(57.34±1.86)
19(151.34±1.23)
2
41
36 (87.81)
35 (97.22)
a
34(97.14)
a
25(71.43)
b
1(2.44±1.23)
36(57.23±2.34)
25(152.71±2.24)
3
38
34 (89.47)
33(97.06)
a
32(96.97)
a
25(75.76)
a
1(2.63±1.24)
34(56.22±2.10)
25(152.85±2.41)
4
33
29 (87.88)
27(93.10)
b
25(92.59)
b
20 (74.07)
a
1(3.03±1.24)
29(56.38±2.30)
20(151.35±1.11
5
30
26 (86.67)
20 (76.92)
d
16(80.00)
c
14(70.00)
b
1(3.33±1.23)
26(57.93±3.45)
14(152.67±1.23)
Age
(Dentition)
*
*
*
*
NS
NS
NS
1
1
45
38 (84.44)
b
34(89.47)
b
31(91.18)
b
22(64.71)
b
2(4.44±1.24)
34(56.98±2.45)
2
2
51
48(94.12)
a
45(93.75)
a
44(97.78)
a
35(77.78)
a
1(1.96±1.23)
48(57.65±1.98)
3
3
48
45(93.75)
a
43(95.56)
a
41(95.35)
a
34(79.07)
a
1(2.08±1.23)
45(57.51±2.12)
4
4
33
25(75.76)
c
21(84.00)
c
18(85.71)
c
12(57.14)
c
1(3.03±1.22)
25(57.71±2.11)
Protocol 1: Single Injection of PGF2α hormone, heat detection and AI within 72 hours; Protocol 2: Single Injection of PGF2α hormone, heat detection and
buck service within 72 hours; Protocol 3: Double Injection of PGF2α hormone at 11days interval, fixed AI at 48 hour post injection; age by dentition (1=1 pairs
of permanent incisors, 2 = 2 pairs of permanent incisors, 3 = 3 pairs of permanent incisors, 4 = 4 pairs of permanent incisors);
*
statistically significantly affected
at P<0.05,
NS
statistically non-significant (P>0.05)
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3.2. Factors affecting the efficiency of the oestrus
synchronization
The present study showed that the rate of does
inseminated, conceived and kid delivered were
significantly affected by protocol, parity, and age
(P<0.05) whereas the oestrus response rate was
significantly affected by age (Table 1).
Does age (dentition 2 and 3) have shown better
oestrus response rate than those of age groups 1 and
4. Studies on dairy cattle oestrous synchronization
found a higher oestrous expression in cows (90.9%)
than in heifers (63%) (Bayemi et al., 2015). The
oestrous responses in Nigerian goat breeds ranged
from 20 to 100% (Omontese et al., 2016). However,
it was not affected by protocol and parity (p>0.05). In
contradiction to this experiment, that Zelelek et al.
(2015) reported lower oestrous response rate (55–
65%) in Ethiopian sheep breeds. Ungerfeld and
Sanchez-Davila (2012) found a significantly higher
oestrous response to hormone treatment in
multiparous ewes (91.5%) than in primiparous ewes
(75.0%).Does insemination rate showed better
performance on protocol type 2; parity 2 and 3, and
does aged 2 and 3.
Protocol type 2 followed by 3; parity 2 and 3, and
does aged 2 and 3 have revealed a better conception
rate. The conception rate on Abergele goat breed
reported by Bekahegn et al. (2022) was lower than
the current finding. Kidding rate was performed
better at protocol type 3; parity 2 and 4, and aged 2
and 3. Almost similar kidding rate was reported by
Bekahegn et al. (2022) on Abergele goat. The
average conception and kidding rates achieved in the
current study were within the range of the conception
rate in Nigerian goat breed ranged from 65.0 to 100%
(Omontese et al., 2016). In contrast, Ungerfeld and
Sanchez-Davila (2012) found a significantly lower
oestrous conception rate was reported although it was
statistically similar (59.6% and 50.0% in multiparous
and primiparous ewes, respectively). Similarly,
studies on dairy cattle revealed a non-significant
difference in conception rates between cows and
heifers (Bayemi et al. 2015). This effect of parity was
independent of age of the ewes, as the two factors
could be confounded. However, estrous detection,
early pregnancy diagnosis, and unknown time of
ovulation, cause low reproduction performance of
goats (Baldassarre and Karatzas, 2004).
Does oestrus duration was better observed at protocol
3 and parity 3 and 4. This might indicate that double
injection and higher parity were conducive for the
oestrus duration. Contradicting result was reported on
Abergele goat (Bekahegn et al., 2022).
On other hand, abortion rate was not statistically
significantly affected by the parameters. Solomon et
al., (2016) observed that AI technicians’ skill on
identification of functional corpus luteum (CL),
parity, protocol and AI skill are important
determinants of successful oestrous synchronization
and pregnancy diagnosis.
Figure 1: Buck serving does on heat (left), and kids born after synchronization (right)
3.3. Reproductive losses of Does
The overall reproductive loss rate was about 44.63%
as depicted in Figure 2. This has indicated that there
was reproduction wastage across reproduction cycles.
The total percent of does didn’t respond, didn’t
inseminate/mate, didn’t conceive, didn’t deliver kid
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and abortion rates were about 11.86%, 7.34%, 6.29%,
23.13%, and 2.82%, respectively. This has indicated
that there was the reproductive wastage across
reproduction cycles due to different factors like
failure to mate; failure of fertilization in mated
animals; loss during any stage of gestation
(embryonic, fetal losses) and neonatal mortality and
subsequent loss occurring until the time of weaning
(ESGPI, 2009).
3.4. Woyto-Guji goat prolificacy
Kid sex born (%) and litter size (%) are presented in
Figure 3. An overall percent of kid sex born was
about 49% male and 51% female. These findings
indicated that almost equal percent of male and
female kids was born, which indicates the natural
norm (ESGPIP, 2009).
About 58 and 42% of kids born were single and twin,
respectively (Figure 3). The current finding revealed
that Woyto-Guji goat breed has lower twinning rate.
These results are in line with the findings of
Abergelle and Central Highland goat breeds (Deribe
2008; Bekahegn et al., 2022). However, higher
prolificacy was observed in Kaffa (Belete, 2009).
Figure 2: Reproductive failure (%) of Does
2.82
11.86
7.34
6.29
23.13
44.63
Does aborted after hormone injection Does didn't respond after hormone injection
Does didn't inseminated/mated after response Does didn't conceived after insemination
Does didn't delivered kid after conception Total reproductive failure
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Figure 3: Sex of kids delivered (left) and liters size (right) after hormone synchronization
4. Conclusion and Recommendations
The response rate was about 88.14% within 57.48 ±
2.64 hours. The overall conception rate and kidding
rate were about 93.71% and 72.03% respectively.
Both conception rate and kidding rate were assumed
to be better indicators of the reproductive
performance efficiency measurement. Non-return to
heat and/or early pregnancy diagnosis for increased
reproduction rate was needed to be more experienced
to minimize reproduction loss. Both single shot and
double shot followed by buck mating and fix AI,
respectively, were better indicators for kidding rate.
However, the use of the single shot followed by buck
mating might be more applicable at the farmer level
to improve oestrus efficiency. Therefore, the
applicability of the protocols at the smallholder level
needs to be given further attention.
Funding statement
This research received financial support from
Ethiopia Institute of Agricultural Research and South
Agricultural Research.
Data availability statement
Data will be made available upon request.
Declaration of interest’s statement
The authors declare no competing interests.
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