RELATIONSHIP BETWEEN PROGESTERONE
CONCENTRATION THROUGHOUT MATING DAY
AND PREGNANCY OF SHE-CAMELS.
Kamel,* M. and Azza A. Helmy
Animal Production Research Institute, Agricultural Research Center,
Dokki, Giza, Egypt.
*Corresponding auther email: makram.kamel.2016@gmail.com
Key Words: she-camels, mating day, plasma progesterone, pregnancy
ABSTRACT
The present work was done to investigate the interrelationship
between progesterone concentration in blood plasma and saliva of female -
camels pre and post - mating day and pregnancy. Thirty healthy female
camels were divided equally according to their age into three groups, G1(3-
5y), G2(5-10y) and G3(10-20y). Blood samples were taken through one
estrous cycle at day before mating (D˗1), mating day (D0), 1st, 2nd, 4th and 8th
day after mating. One sample of saliva per female was taken at day 8 postmating
for progesterone assay to compare between plasma and salivary
progesterone concentrations. At days before the 4th day of mating,
progesterone concentrations were undetectable in all groups (< 0.5 ng/ml).
Beginning from day 4, all groups showed a similar detectable level of
progesterone, the mean was (1.17, 1.20 and 1.22 ng/ml) for G1,G2 and G3,
the progesterone mean significantly increased at the 8th day to reach (4.09,
4.54 and 4.58 ng/ml) for G1, G2 and G3, respectively. At 8th day, the mean
of progesterone level for pregnant camels was (6.15, 5.74 and 5.73 ng/ml)
for G1, G2 and G3, respectively. Whereas, in non-pregnant camels at 8th day
the mean of progesterone level was significantly less (3.21, 3.34 and 3.42
ng/ml) for G1, G2 and G3, respectively. There was consistency between
plasma and salivary progesterone concentrations, the mean salivary
progesterone level in pregnant camels at 8th day was significantly higher for
G1, G2 and G3, respectively (4.96, 4.63and 4.58 ng/ml) comparing with
non-pregnant camels for the three groups (2.49, 2.64 and 2.73 ng/ml).
However, this noticeable increase of plasma and salivary progesterone level
in pregnant camels at 8th day post-mating could be considered as early
diagnostic indicator for pregnancy in camels.
INTRODUCTION
Camels were reported to have low reproductive efficiency under
normal conditions (Kaufmann, 2005). Skidmore (2013) indicated that
the reproductive performance of camels is generally regarded to be low
(40%), this could be due to the late age of reaching puberty (3 - 4 years),
the long gestation period (13 months) and the relatively high incidence of
abortions and non-conceptions possibly attributed to poor nutrition, poor
Egypt. J. of Appl. Sci., 36 (5-6) 2021 95-102
management, limited breeding opportunities for the females due to
seasonality of breeding.
Camels reproduction displayed by different constrains as semen
characteristics, long gestation period, late sexual puberty and maturity,
limited breeding season and the mechanism of estrous cycle and
ovulation of she- camel (Deen, 2008; EL-Hassanien et al., 2010).
Dromedary camels are considered as seasonal breeding animals. In
Egypt, breeding season has been prolonged from December to April
(Shalash, 1980; 1987). Zeidan, (1999) reported low calving rate of
camels approximately 41% in Egypt.
Breeders often tend to breed camels early in the season for better
growth of calves (born between November to January) born to early bred
females. The pregnancy rates during early season tend to be poor because
of transition from summer anestrus and poor follicle growth during this
period (Sghiri and Driancourt, 1989).
In managing any camelid herd efficiently there is a definite need to
diagnose pregnancy as accurately and as soon as possible after mating so
that if the camel is not pregnant she can be re-mated, re-inseminated or
returned to an embryo transfer programme. There are several methods
used to diagnosis pregnancy but it must be remembered that whatever
method is used, a single pregnancy diagnosis is not sufficient to
guarantee a birth, especially if done at a very early stage (i.e. before 40 -
50 days post mating). This is due in part to errors in diagnosis, but is also
due to the high incidence of early embryo loss seen in these species.
Further examinations should therefore be carried out at 3 - 4 months of
gestation to ensure the pregnancy is developing normally (Skidmore,
2000).
Studies on progesterone concentrations during pregnancy in the
camelidae confirm that these species depend on ovarian progesterone
throughout their pregnancy. Ablation of the CL-bearing ovary or
administration of PGF2α or its analogue causes abortion or premature
parturition at all stages of pregnancy, thus it would seem likely that the
placenta either fails to secrete progesterone at all, or it does so in
amounts insufficient to maintain pregnancy without help from the ovaries
(Sumar, 1988).
In the mated dromedary, serum progesterone concentrations
increase from day 3 after ovulation to concentrations of around 3.4
ng/ml by day 8. If the camel is not pregnant concentrations rapidly return
to basal levels of <1ng/ml by days 10 - 12, however, if she is pregnant
the progesterone concentrations are maintained between 3 and 5 ng/ml
for the first 90-100 days of gestation. According to some studies,
progesterone levels then decrease slightly to 2 - 4 ng/ml where they
remained until day 300. A further slight decrease then occurs over the
96 Egypt. J. of Appl. Sci., 36 (5-6) 2021
next 70 - 80 days followed by a rapid drop to values of day before, or the day of parturition (Skidmore et al., 1996).
The measurement of progesterone concentration in peripheral
blood can thus be invaluable in the early detection of pregnancy. If a
blood sample is taken between days 12 - 15 and the value is still high (i.e.
>1.0 ng/ml) this would indicate that the camel is possibly pregnant. If the
value has dropped to pregnant.
The concentration of steroid hormones in a female animal is
an indicator of reproductive status. Progesterone enters the saliva
via passive diffusion from the salivary glands. The level of
progesterone present in the saliva of the horse and man can be
used to diagnose pregnancy by use of an Enzyme-Linked
Immunosorbent Assay [ELISA] (Smith, 2005; Kaufman and
Lamster, 2002). The need for a non-invasive pregnancy
diagnosis test, the development of a reliable and accurate
pregnancy diagnosis test for use on farm animals for the early
diagnosis of pregnancy would enable the prompt rebreeding of
nonpregnant animals and prevent the culling of pregnant animals
in error.
The objective of this study is to investigate the relationship
between plasma and salivary progesterone level of female – camels
around mating day and early pregnancy diagnosis.
MATERIALS AND METHODS
1- Animals
The study was carried on female camels (Camelus dromedaries)
that belonging to a private camel farm for camel breeding, located in
Matrouh Governate, during the period from November 2018 until June
2020. A total of thirty healthy female camels at different ages were
equally divided based on their ages into three groups, the age and body
weight of groups were illustrated in Table (1).
Table(1): Numbers, age and body weight of female camels
Groups
(no.)
Age (year)
Average of body weight
(kg) Means±S.E
Range of
body weight (kg)
G1(10) 3-5 430.50±6.78 395-465
G2(10) 5-10 486.90±6.23 460-515
G3(10) 10-20 537.90±5.42 517-563
Camels were fed per head twice daily (at 8 a.m. and 6 p.m.) of 7 kg
of a forage mixture barley straw (Hordeum vulgare) and 3-4 kg of a
commercial feed concentrate mixture (12% CP). Female groups were
kept in three fenced sand pens with appropriate wide area for moving
easily through the mating periods.
Egypt. J. of Appl. Sci., 36 (5-6) 2021 97
2- Samples
a-Blood samples were taken throughout one estrous cycle for all
camels during the period of breeding season, female camels were noticed
for showing estrous behavior: (frequent urination, restlessness, vaginal
discharge and male acceptance), then estrus females were separated, at
next day, females were naturally mated with fertile male, then they were
being held to perform sampling, as it is described below.
Blood samples per female camel were taken via jugular vein as
follows: at pre-mating day (D˗1), mating day (D0) and 1st, 2nd, 4th, 8th
days post-mating. Blood samples were collected in an EDTA tubes,
plasma were harvested following centrifugation at 2000 rpm for 10
minutes, and stored under ˗20º until time of progesterone assay, plasma
progesterone concentrations (ng/ml) were measured by specific
radioimmunoassay (RIA) commercial kits of (Diagnostic Systems
Laboratories) DIAsource ImmunoAssays® S.A, Louvain-la-Neuve –
Belgium.
b- Salivary samples one salivary sample was taken per female at
day 8 post-mating , it was performed by moving a plastic straw inside the
camel's mouth, collecting saliva in a tube, then it was filtered, the clear
liquid was taken, and stored under ˗20º for progesterone assay.
3- Statistical analysis
Data were statistically analysed by the General Linear Model
(GLM), using SAS (2002). Differences between means were then tested
using Duncan's multiple range test (1955). Results are presented as least
squares means and their corresponding standard errors.
RESULTS AND DISCUSSION
Plasma progesterone concentrations
Table (2) indicated that the three groups generally showed similar
undetectable increase of progesterone concentrations (<0.50ng/ml)
throughout the day before mating, mating day, day1, and day2 after
mating. Progesterone concentrations were slightly increased significantly
at day4 followed by greater significant increase at day 8 post-mating for
the three groups. At day 8 groups 2 and 3 showed a higher close values
of progesterone level (4.54±0.51 and 4.54±0.50 ng/ml), while group 1
showed slightly less value (4.09±0.48 ng/ml).
The S.E values were very small and much close into all groups
from D˗1 till 2nd day, which reflected the similarity of the low
progesterone concentrations in all groups at these days, and indicated that
difference inside groups was minimal. Beginning from day 4,
progesterone levels were increased above (1.0 ng/ml) and S.E increased
inside every group, reflecting increasing variation between camels inside
every group, similarly significant increase in values of progesterone
concentrations as well as S.E values meaning more variation between
98 Egypt. J. of Appl. Sci., 36 (5-6) 2021
camels, which is due to ovulation after mating and formation of corpus
luteum secreting significant amount of progesterone.
Table(2): Plasma progesterone levels (ng/ml) of groups as
(Means±S.E)
Group
Days
D-1 D 0 D 1 D 2 D 4 D 8
G1 0.20c ± 0.02 0.43c ± 0.02 0.43c ± 0.03 0.45c ± 0.03 1.17b ± 0.12 4.09a ± 0.48
G2 0.19c ± 0.02 0.43c ± 0.03 0.43c ± 0.03 0.45c ± 0.05 1.20b ± 0.13 4.54a ± 0.51
G3 0.20c ± 0.02 0.44c ± 0.03 0.44c ± 0.03 0.44c ± 0.04 1.22b ± 0.13 4.58a ± 0.50
Means with different superscripts letters in the same row are differed significantly
at (P <0.05),
Kamoun and Jemmali (2014) reported that progesterone level
rise after a successful mating This significant rise was ≥ 2.96 ng/ml two
days after mating in all females, which disagree with the current study.
Skidmore et al., (1996) reported that serum progesterone concentration
increase from 3rd day after ovulation to concentrations of around (3.4
ng/ml) by 8th day. If the camel is not pregnant concentrations rapidly
return to basal levels of (<1ng/ml) by days (10 – 12) after mating, these
results agree with the results of this study.
Plasma progesterone levels of pregnant and non-pregnant camels
Table (3) illustrated means of progesterone values for pregnant and
non-pregnant camels, means of days (D-1, D0, D1and D2 after mating)
showed increasing but undetectable values of progesterone in all groups.
Table(3): Plasma progesterone levels (ng/ml) of pregnant and nonpregnant
camels as (Means±S.E)
Days Case
Groups
G1(3/10) G2(5/10) G3(5/10)
D-1
Non. 0.17g ± 0.15 0.13g ± 0.18 0.13g ± 0.18
Preg. 0.25gf ± 0.23 0.26gf ± 0.18 0.27gf ± 0.18
D0
Non. 0.38egf ± 0.15 0.35egf ± 0.18 0.35egf ± 0.18
Preg. 0.55egdf ± 0.23 0.52egdf ± 0.18 0.52egdf ± 0.18
D1
Non. 0.38egf ± 0.15 0.35egf ± 0.18 0.35egf ± 0.18
Preg. 0.55egdf ± 0.23 0.52egdf ± 0.18 0.52egdf ± 0.18
D2
Non. 0.41egf ± 0.15 0.32egf ± 0.18 0.33egf ± 0.18
Preg. 0.56egdf ± 0.23 0.58egdf ± 0.18 0.55egdf ± 0.18
D4
Non. 0.99d ± 0.15 0.84edf ± 0.18 0.86ed ± 0.18
Preg. 1.58c ± 0.23 1.57c ± 0.18 1.59c ± 0.18
D8
Non. 3.21b ± 0.15 3.34b ± 0.18 3.42b ± 0.18
Preg. 6.15a ± 0.23 5.74a ± 0.18 5.73a ± 0.18
Numbers between brackets refer to the pregnant camels in each group.
Means with different superscripts letters in the same column are differed significantly at
(P <0.05),
Non. = Non-pregnant, Preg.= Pregnant
At day 4 post mating, pregnant camels in the three groups showed
similar progesterone mean values that exceeded (1.0ng/ml), means were
(1.58, 1.57 and 1.59 ng/ml) for G1, G2 and G3, respectively. By 8th day
post mating, plasma progesterone mean values increased significantly,
Egypt. J. of Appl. Sci., 36 (5-6) 2021 99
pregnant camels of G1 showed the higher mean value (6.15 ng/ml)
comparing with G2(5.74ng/ml) and G3(5.73ng/ml), this higher value of
G1mean may be due to small number of pregnant camels of this
group(3/10), whereas G2 and G3 had more number of pregnant animals
(5/10).
For non-pregnant camels in the three groups, progesterone levels at
day 4 showed limited rise values, but not overreach (1.0ng/ml), while at
day 8 after mating progesterone means increased significantly for nonpregnant
camels of the three groups comparing progesterone means of
day4, G1(3.21ng/ml), G2 (3.34 ng/ml) and G3(3.42 ng/ml).
The results of the current study agree with those of (Bravo et al.,
1996) in pregnant llamas and alpacas, as progesterone was detectable 4 days
after breeding and was maintained > 2 ng/ml throughout pregnancy. While
the current results disagree with those of (Kamoun and Jemmali, 2014)
who reported, in Camillus dromedaries, slightly higher figures during
pregnancy in the first half than the second half 4.37±1.38 ng/ml vs.
3.70±0.96 ng/ml. Moreover, the results match also with (Zhao et al., 1998)
who reported higher serum progesterone concentrations in Bactrian camel
(3.06±0.49 to 8.51±4.80 ng/mL) throughout most of gestation.
Salivary progesterone of pregnant and non-pregnant camels
Table 4 presented collective data of salivary progesterone mean at
day 8 for the three groups, and salivary progesterone mean at day 8 for
pregnant and non-pregnant camels in all the groups.
Group1showed the least mean of salivary progesterone (3.23
ng/ml), G2 and G3 had closed salivary progesterone means, for G2 (3.63
ng/ml) and G3 (3.65 ng/ml).
Pregnant camels from G1 showed higher significant progesterone
mean (4.96 ng/ml), while means of pregnant camel of G2 (4.63 ng/ml)
and G3 (4.58 ng/ml) had closed and non-significant means.
Non-pregnant camels of the three groups showed lower nonsignificant
means comparing of pregnant camels, salivary progesterone
means were (2.49, 2.64and 2.73 ng/ml) for G1, G2 and G3, respectively.
Table (4): Salivary progesterone levels (Mean±S.E) (ng/ml) of
pregnant and non-pregnant camels
Groups
Progesterone
level (D8)
Case
Progesterone
level (D8)
G1 3.23bc ± 0.43
Non. 2.49c ± 0.23
Preg. 4.96a ± 0.57
G2 3.63bac ± 0.47
Non. 2.64c ± 0.37
Preg. 4.63ba ± 0.61
G3 3.65bac ± 0.45
Non. 2.73c ± 0.33
Preg. 4.58ba ± 0.63
Means with different superscripts letters in the same column are differed significantly at (P
<0.05),
Non.=Non-pregnant , Preg.=Pregnant
100 Egypt. J. of Appl. Sci., 36 (5-6) 2021
REFERENCES
Bravo P.W. ; D.R. Stewart; B.L. Lasley and M.E. Fowler (1996).
Hormonal indicators of pregnancy in llamas and alpacas.
Journal of the American Veterinary Medical Association, 208
(12):20-30.
Deen, A. (2008). Why artificial insemination in dromedaries is not
successful? Proceeding of the WBC / ICAR, Satellite Meet.
Camelid. Reprod. Budapest, Hungary, p.28-32.
Duncan, (1955). Multiple range and multiple F tests. International
Biometric Society. 11 (1):1-42.
El-Hassanien, E.E. ; K.A. El- Bahrawy and A.A. Zagloul (2010).
Artificial insemination and ovulation in the dromedary shecamel.
Journal of Nature and Science., 8(9):203-208.
Kamoun, M. and B. Jemmali (2014). Serum progesterone level of
camel (Camelus domedarius) according to the physiological
status. Journal of New Sciences,3(2):10-21.
Kaufman, E. and I.B. Lamster (2002). The diagnostic applications of
saliva: A review. Critical Reviews in Oral Biology and
Medicine., 13. (2):197-212.
Kaufmann, B.A. (2005). Reproductive performance of camels (Camelus
dromedaries) under pastoral management and its influence on
herd development. Livestock Production Science. 92: 17-29.
SAS (2002). Statistical analysis system, SAS User Guide (SAS),INC
Sghiri, A. and M.A. Driancourt (1989). Seasonal effects on fertility and
ovarian follicular growth and maturation in camels (Camelus
dromedarius). Anim Reprod Sci., 55: 223-37.
Shalash, M .R. (1987). Review Article: Reproduction in camels. Egypt.
J. Vet. Sci., 24:1- 25.
Shalash, M.R. (1980). Reproduction in camel. In: Proceedings of the 9th
Int Congress Anim Prod and AI, Madrid, Spain, 559-567.
Skidmore, J.A. (2000). Pregnancy Diagnosis in Camels. In: Recent
Advances in Camelid Reproduction, Skidmore J.A. and Adams
G.P. (Eds.)pp.1-6. Publisher: International Veterinary
Information Service (www.ivis.org).
Skidmore, J.A. (2013). Methods to improve the reproduction of camel.
In: Proceedings of the International Scientific Conference of
Camel Research and Production (ISCCRP) 17th-18th April.
Khartoum-Sudan., Pp. 83 – 90.
Skidmore, J.A. ; M. Billah and W.R. Allen (1996). Patterns of hormone
secretion throughout pregnancy in the one-humped camel
(Camelus dromedarius). Reprod. Fertil. Dev., 8: 863-869.
Egypt. J. of Appl. Sci., 36 (5-6) 2021 101
Smith, K. (2005). Measuring progesterone levels in saliva to monitor
reproductive function in the mare. BSc dissertation. University
of Nottingham.
Sumar, J. (1988). Removal of the ovaries or ablation of the corpus
luteum and its effect on the maintenance of gestation in the
alpaca and llama. Acta. Vet. Scand., 83:133-141.
Zeidan, A.E.B. (1999). Effect of age on some reproductive traits of the
male one-humped camels (Camelus dromedaries). Zagazig Vet.
J., 27: 126-133.
Zhao, X.X. ; Y. Zhang and B.X. Chen (1998). Serum progesterone and
17 β- estradiol concentrations during pregnancy of Bactrian
camel. Theriogenology, 50(4):595-604.
العلاقة بين مستويات البروجستيرون خلال يوم الت ا زوج
وبداية حدوث الحمل فى النوق
مکرم کامل إب ا رهيم ، عزه أحمد حممى
معهد بحوث الإنتاج الحيوانى- الدقى- الجيزة - مصر
تهدف الد ا رسة الى بحث العلاقة بين مستويات البروجستيرون فى بلازماا الادو وفاى البعاان لبناو قبا و
بعاد ياوو التبحايب و بداياة حادوث الحما . اساتعدو لبد ا رساة ,ادد قلاقاين ناقاةع تاو تحسايمها تبعاا لبعمار الاى قالاث
مجمو,اات متسااوية فاى العاددع تاو اعا ,يناات الادو بياوو قبا التا ا زوج و فاى ياوو التا ا زوج و بعاد بياوو و بعاد
بياومين و بعاد بةربعاة ايااو و بعاد بقمانياة ايااو. و تاو اعا ,يناة لعاان مان الحيواناات ابهاا فاى الياوو القاامن بعاد
الت ا زوج. تو تحدير البروجستيرون فى ,ينات بلازما الدو و,ينات البعان.
وجاد ان مساتويات البروجساتيرون فاى بلازماا الادو لبمجمو,اات ابهاا فاى اايااو قبا الياوو ال ا ربا اانات
تراي ا زت ضئيبة جدا )اق من 0,5 نانوج ا رو/م ( . بدءا من اليوو ال ا رب بعد الت ا زوج اظهارت الحيواناات زياادة فاى
ع G و 3 G و 2 G مسااتويات البروجسااتيرون ع ااااان المتوساا ) 1.17 ع 1.20 ع 1.22 ناااان وج ا رو / ماا ( لااا 1
وا زد متوساا البروجسااترون بشااا مبحااوظ فاا اليااوو القااامن ليصاا إلااى ) 4.09 و 4.54 و 4.58 نااان وج ا رو /
باى التاوال . فا الياوو القاامن ع ااان متوسا مساتو هرماون البروجساترون لبناو , G و 3 G و 2 G ما ( لا 1
باى التاوال ع بينماا فا الناو يار , G و 3 G و 2 G الحوام ) 6.15 ع 5.74 ع 5.73 نانوج ا رو / ما ( فا 1
الحواما فا الياوو القاامن ااان متوسا مساتو البروجساترون اقا معنويا ا ) 3.21 ع 3.34 و 3.42 ناانوج ا رو/
بى التوال . , G و 3 G و 2 G م ( لا 1
اان هناک تناس بين تراي ا زت البروجسترون ف البلازما والبعان ع وااان متوسا مساتو البروجساترون
بااى التااوال ) 4.96 و 4.63 و , G و 3 G و 2 G فاا النااو الحواماا فاا اليااوو القااامن ا,بااى معنويااا فاا 1
4.58 نانوج ا رو / م ( محارناة باالن و يار الحواما فا المجمو,اات القلاقاة ) 2.49 و 2.64 و 2.73 ناانوج ا رو
/ ما (. مان ها الزياادة المبحوظاة فا مساتو البروجساترون فاى البعاان والبلازماا فا الناو الحواما فا الياوو
القامن بعد الت ا زوج يمان ا,تبارها امؤشر تشعيصى مبا ا ر لحدوث الحم ف النو .
102 Egypt. J. of Appl. Sci., 36 (5-6) 2021
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