This study assessed the reproductive performance of Djallonke sheep in northern Ghana. Key findings include: - Age at puberty for gimmers was 220 days on average, with rainy season born gimmers reaching puberty 36 days earlier. - Postpartum ewes resumed cycling 69 days after lambing on average. - Average age at first parturition was 594.8 days. Lamb birth weight was 2.57kg on average and increased with parity. - Prolificacy was low at 1.05 lambs/ewe but increased with parity. Lambing intervals averaged 267.4 days and decreased with parity. - Pre-weaning mortality was 28

1. THE REPRODUCTIVE
PERFORMANCE OF DJALLONKE
SHEEP IN THE NORTHERN
REGION OF GHANA
SADAT SALIFU
KWAME NKRUMAH UNIV. OF SCI. AND TECH.
2014

2. INTRODUCTION
• Small ruminants make up 17% of the traditional livestock population and
contribute 49% of ruminant livestock meat in Ghana (FAOSTAT, 2009).
• They are a key component of the farm enterprise in Northern Ghana, with
farming households usually keeping about 10 to 20 sheep per household
(Avornyo, 2007)

3. INTRODUCTION CNTD.
• Demand for meat in Sub-Saharan Africa is increasing and it is imperative that a
corresponding increase in livestock productivity take place to keep up with the
demand.
• Reproductive rate is a key measure of the productivity of livestock. Important
indices of reproductive performance include ; Age of puberty, Age at first
parturition, Prolificacy, Lambing intervals, Birth weights of lambs, Annual
reproductive rate (ARR).

4. OBJECTIVES OF STUDY
This study was therefore undertaken to assess the reproductive performance of
Djallonke sheep in the dry Savannah zone of Ghana.
Specific objectives were to;
1. Determine the age at puberty of gimmers and the length of postpartum
return to oestrus of postpartum ewes using progesterone measurements.
2. Obtain baseline data on the reproductive performance of Djallonke sheep in
the Northern Region of Ghana.
3. Examine the effect of parity of dam, sex of offspring, season of birth and
location on reproductive performance.
4. Assess the reproductive losses that occur prior to weaning

5. MATERIALS AND METHODS
Two separate investigations were carried out in this study:
1. Progesterone-monitoring study and
2. Analysis of farm reproductive data
Progesterone Monitoring Study
Study Location: Pong Tamale Livestock Breeding Station , Northern Region.
Experimental Animals:
• 20 gimmers, aged about 4 months (10 dry season and 10 rainy season
born).
• 20 postpartum ewes (10 dry season and 10 rainy season) monitored
from 1 week postpartum.

6. MATERIALS AND METHODS
MANAGEMENT OF ANIMALS
Semi-intensive system where they were grazed during the daytime (from 9am to
5pm) and were housed at night.
FEEDING OF ANIMALS
• Rainy season: Sheep grazed on pastures of Stylosanthes hamata and Cajanus
cajan.
• Dry season: Zero-grazing was practiced in the dry season where the animals
were offered crop residue such as groundnut tops, rice straw, and Cajanus
waste. They were also fed whole cotton seed. Water was supplied in the
paddocks and at various points on the farm.

7. MATERIALS AND METHODS
Data collected and statistical analysis
• Live weight: The animals were weighed monthly and the mean daily growth was
computed from the live weights.
• Progesterone measurements: Blood samples
were collected by jugular venipuncture into
4mls vacutainer tubes and serum was separated
later at the Pong Tamale Central Laboratory and
stored at -200 Celsius until analysis for
progesterone.
•

8. MATERIALS AND METHODS
• Sera were assayed for progesterone using the Enzyme-linked immunosorbent
assay technique (ELISA). ELISA kits were obtained from DRG-International,
New Jersey, USA.
• Sampling frequency was two times per week for gimmers and once per week
for postpartum ewes (four gimmers (2 for each season) and 4 ewes (2 for each
season) were bled every two days for a closer monitoring of their oestrous
cycles).
• Oestrus was checked daily using a ram fitted with a raddle containing a crayon.

9. MATERIALS AND METHODS
• STATISTICAL ANALYSIS
• One-way ANOVA was used to analyze data for the progesterone monitoring
experiment, with season as the factor.

10. MATERIALS AND METHODS
ANALYSIS OF RETROSPECTIVE DATA
Sources Of Data:
• AKANA Farms, Kpatili, near Gushiegu
• Savelugu disease investigation farm, Savelugu
• CSIR-Animal Research Institute farm, Nyankpala.
Reproductive Indices Computed From Data:
• Age at first parturition
• Prolificacy
• Lamb birth weight
• Lambing intervals
• Pre-weaning mortality
• Annual Reproductive Rate (ARR)

11. STATISTICAL ANALYSIS
• The general linear model (GLM) procedure of SAS was used to analyze the
effect of season, parity of dam, sex and location on age at first parturition,
lamb birth weights, prolificacy and lambing intervals.
• The Duncan’s Multiple Range Test was used to separate means.
• The chi-squared test of association was used to analyze the effect of season of
birth, sex of offspring and location on pre-weaning mortality

12. RESULTS AND
DISCUSSION
PART ONE:
PROGESTERONE MONITORING STUDY

13. REPRODUCTIVE
PARAMETERS OF
GIMMERS
TABLE 1: EFFECT OF SEASON ON REPRODUCTIVE PARAMETERS OF DJALLONKE GIMMERS
Parameter Overall Rainy season Dry season Significance
Mean age at first P4
rise (days)
220.6±9.18 202.4±10.63a 238.7±13.03b P<0.05
Mean weight at first
P4 rise (kg)
12.85±0.27 13.05±0.46 12.65±0.29 NS
Age at first overt
oestrus (days)
289.3±15.36 262.4±9.5 316.2±27.3 NS
Mean age at first
lambing (days)
460.2±17.82 424.6±11.14a 495.8±30.57b P<0.05
Mean lamb birth
weight (kg)
1.56±0.08 1.77±0.08a 1.40±0.13b P<0.05

14. REPRODUCTIVE PERFORMANCE OF GIMMERS
• Age at first progesterone rise averaged 220 days.
• Rainy season gimmers showed their first elevation in
progesterone 36 days earlier than the dry season gimmers
(P<0.05) and also lambed earlier than the dry season gimmers.
• The rainy season gimmers in this study grew faster than their
dry season counterparts (45g/day vs 37g/day) and therefore
displayed first rise of progesterone earlier and also lambed
earlier.
• Puberty is closely related to body weight in most domestic
animal and it is known that faster growing sheep generally
come into puberty sooner than their slower growing
counterparts (Dyrmundsson, 1973; Foster and Nagatani,
1999).

15. PROGESTERONE PROFILE OF PUBERTAL GIMMERS
Figure 1: Progesterone profile of gimmer showing multiple elevations and mating

16. PROGESTERONE PROFILES
• Sheep approaching puberty or returning from seasonal or postpartum
anoestrus tend to show one or more elevations of progesterone.
• The first few elevations are usually of irregular length and are not
accompanied by oestrus or ovulation.
• These initial rises are needed to prime the central nervous system to become
more responsive to oestrogen which elicits oestrus behavior in the female
animal.

17. REPRODUCTIVE PARAMETERS OF
POSTPARTUM EWES
TABLE 2: EFFECT OF SEASON ON REPRODUCTIVE PARAMETERS OF POSTPARTUM EWES
PARAMETER OVERALL RAINY SEASON EWES DRY SEASON EWES SIGNIFICA
NCE
Days from lambing to first
P4 rise (days)
69±6.73 68.11±6.19 71.40±11.88 NS
Days from lambing to first
overt oestrus (days)
108.1±10.10 101±12.48 114±15.93 NS
Lambing Interval (days) 266.7±11.35 264.2±14.65 268.7±17.41 NS
Mean lamb birth
weight(kg)
2.04±0.1 2.32±0.13a 1.83±0.11b
P<0.05

18. POSTPARTUM EWES
• Postpartum cycling began 69 days postpartum and first oestrus was detected
108 days after the lambing.
• There was no significant difference between seasons for both parameters.
• Lambing intervals averaged 266 days.

19. PROGESTERONE PROFILES OF POSTPARTUM EWES
Figure 2: Progesterone profile of postpartum ewe with first rise at 60
days and first mating at 88 days

20. PROGESTERONE PROFILE OF POSTPARTUM EWES
• Postpartum ewes undergo a period of reproductive repair during which
oestrous cyclicity ceases.
• Ewes returning to cyclical activity experience one or more elevations of
progesterone which may be luteinized corpora lutea or silent ovulations.
• Progesterone from the initial oestrus cycles primes the central nervous system
to be more responsive to oestrogen.

21. PART TWO:
REPRODUCTIVE PERFORMANCE BASED ON FARM DATA

22. AGE AT FIRST PARTURITION
Table 3: Effect of various factors on age at first parturition
Factor No of observations Age at first parturition
OVERALL MEAN 104 594.8±15.32
SEASON
Rainy season 43 566.7±22.95
Dry season 61 614.6±20.28
ORIGIN/STATION
Akana farms 85 600.8±16.08a
Savelugu farm 8 671.2±14.70a
CSIR-ARI farm 11 496.1±34.16b

23. AGE AT FIRST PARTURITION
• Mean age at first parturition was 594.8 days
• Age at first parturition differed significantly between stations (P<0.05). It was
lowest for stations where rams were allowed to roam with the females (CSIR-
ARI=496.1 days) and higher at stations where breeding was controlled
(Akana=600.8 days and Savelugu=671 days)

24. LAMB BIRTH WEIGHT
TABLE 4a: EFFECT OF VARIOUS FACTORS ON BIRTH WEIGHT OF LAMBS
FACTOR Observations Birth weight (kg) ± S.E.M.
OVERALL MEAN 1049 2.57±0.05
PARITY
1st 359 2.49±0.03d
2nd 202 2.48±0.04d
3rd 146 2.6±0.04cd
4th 127 2.46±0.04cd
5th 90 2.52±0.05cd
6th 54 2.67±0.07bc
7th 30 2.87±0.10ab
>8th 41 2.95±0.08a

25. LAMB BIRTH WEIGHT
TABLE 4b: EFFECT OF VARIOUS FACTORS ON BIRTH WEIGHT OF LAMBS
FACTOR Observations Birth weight (kg) ± S.E.M.
SEASON
Rainy season 450 2.57±0.03a
Dry season 599 2.46±0.03b
SEX
Male 511 2.52±0.03
Female 538 2.48±0.03
LOCATION
Akana farm 804 2.67±0.02a
Savelugu farm 186 2.03±0.03b
CSIR-ARI farm 59 1.59±0.04c
TYPE OF BIRTH
Singles 938 2.53±0.02a
Twins 111 2.25±0.05b

26. LAMB BIRTH WEIGHT
• Lamb birth weight averaged 2.57kg.
• Birth weight increased significantly with parity from the 1st to the 8th parity.
From the 1st to 8th parity, the increment was about 460g.
• The rainy season was associated with higher birth weights compared to the
dry season (2.57kg vs. 2.46kg)(P<0.05)
• Singleton lambs were also significantly heavier than lambs born as twins
(2.53kg vs 2.25kg)

27. EWE PROLIFICACY
TABLE 5a: EFFECT OF VARIOUS FACTORS ON PROLIFICACY
Factor No of observations Prolificacy ± S.E.M.
OVERALL MEAN 998 1.05±0.0074
PARITY
1st 348 1.03±0.01b
2nd 197 1.03±0.012b
3rd 138 1.05±0.018b
4th 118 1.09±0.029b
5th 85 1.06±0.025b
6th 49 1.10±0.041ab
7th 28 1.10±0.052ab
>8th 35 1.20±0.057a

28. EWE PROLIFICACY
TABLE 5b: EFFECT OF VARIOUS FACTORS ON PROLIFICACY
FACTOR Number of
observations
Prolificacy
± S.E.M.
SEASON
Rainy season 420 1.04±0.01
Dry season 578 1.06±0.01
LOCATION
Akana farm 761 1.06±0.01a
Savelugu farm 178 1.04±0.02ab
CSIR-ARI farm 59 1.00±0b

29. EWE PROLIFICACY
• Prolificacy was generally low (1.05) since only about 6% of the 998 births were
twin births.
• Prolificacy increased significantly with increase in parity (P<0.05)
• Prolificacy also differed across stations, with Akana farms having the highest
prolificacy (1.06), followed by Savelugu farm (1.04) and lastly CSIR-ARI farm
(1.0).

30. LAMBING INTERVALS
TABLE 6a: EFFECT OF VARIOUS FACTORS ON LAMBING INTERVALS
FACTOR Number of observations Lambing intervals (days)
Overall 603 267.4±2.78
Parity
2nd
158 280.0±5.73a
3rd
124 262.6±6.01ab
4th
107 269.8±6.63ab
5th
82 269.5±7.65ab
6th
54 261.9±10.02ab
7th
39 254.9±9.22ab
8th
22 237.3±7.83b
9th
17 244.7±11.67b

31. LAMBING INTERVALS
TABLE 6b: EFFECT OF VARIOUS FACTORS ON LAMBING INTERVALS
Variable Number of observations Lambing intervals (days)
Season
Rainy season 269 272.9±4.35
Dry season 334 262.9±3.57
Origin
Akana farms 510 268.4±2.93a
Savelugu farm 46 292.0±5.34b
CSIR-ARI farms 47 232.2±14.33c

32. LAMBING INTERVALS
• Lambing intervals averaged 267.4 days
• Lambing intervals decreased significantly with parity from the 2nd to 9th parity
(280.0 days to 244.7 days).
• The lambing interval was lowest for CSIR-ARI farm (232.2 days), followed by
Akana farms (268.4 days) and lastly Savelugu farm (292 days).

33. PRE-WEANING MORTALITY
TABLE 7: EFFECT OF VARIOUS FACTORS ON LAMB PRE-WEANING MORTALITY
Factor Number Proportion surviving Proportion dying
Overall 804 578 (71.9%) 226 (28.1%)
Season
Rainy season 336 280 (83.3%) 56a (16.7%)
Dry season 468 298 (63.7%) 170b (36.3%)
Sex of lamb
Male 386 274 (71.1%) 112 (28.9%)
Female 418 304 (72.6%) 114 (27.4%)
Type of birth
Single 720 518 (71.9%) 202 (28.1%)
Twin 84 60 (71.4%) 24 (23.6%)

34. PRE-WEANING MORTALITY
• Overall preweaning mortality rate was 28.1%
• Lambs born in the dry season tended to die more than lambs born in the rainy
season (36.3% vs 16.7%).
• High mortalities in the dry season could be a result of inadequate nutrition for
the dam during the period which results in starvation of the lambs.

35. ANNUAL REPRODUCTIVE RATE
• The annual reproductive rate (lambs weaned per ewe of reproductive age per
year) was 1.03, due to the low incidence of twinning (6%) and high mortality
rate of 28.1%.

36. CONCLUSION
• Djallonke sheep reach puberty when they are 7 months and are first mated
when they are 8 months old. They would lamb around 15 months if mating is
not controlled and around 19 months if mating is controlled.
• Early attainment of puberty and early lambing are favoured by lambing in the
rainy season due to availability of feed resources.
• Postpartum ewes return to cycling about 69 days after their last lambing, mate
at about 108 days postpartum. Lambing intervals average about 266 days (9
months).
• Though lambing intervals are usually adequate (8.8 months), the low
prolificacy and high pre-weaning mortality rate result in a decrease in
productivity.

37. RECOMMENDATIONS
1. Adequate feeding of animals in the dry season to make up for the shortfall
of grazing material could reduce the age at puberty and advance age at first
lambing of gimmers
2. Instituting health regimes that target the reduction in the high pre-weaning
mortality would improve the annual reproductive rate.
3. Targeted feeding of lactating ewes in the dry season could also reduce the
high mortality rate in the dry season which is likely caused by starvation.

38. THANK YOU