Introduction
The goat is known as the cow of a poor man, Goats are an animal that adapts to almost any climate [1]. Goats are generally classified as seasonal polyestrous breeders and breeder for short days in temperate zones, seasonal variation between breeds, and their locations [2]. Reproductive performance depends on the interaction between genetic factors and environmental factors [3]. Estrus synchronization in livestock is one of the important methods in assisted reproductive technologies in goat reproduction [4]. In veterinary medicine, administrated of (sulpiride) as dopamine antagonists in small ruminants, might represent a valid alternative to the current drugs used for the synchronization such as melatonin, prostaglandins, and progesterone [5,6]. The sulpiride can be used as a non-steroidal alternative to stimulate luteinizing hormone in goats [7,8]. The sulpiride was used in seasonally anestrus goats leading to an increase in the ovulation rate by stimulating GnRH secretion [9]. The sulpiride was used for the induction of fertile estrus as a non-hormonal method that induction ovulation in out-breeding season ewes [10].
The aim of this study is the induction of fertile estrus during the anestrus season by sulpiride in Iraqi local goats.
Materials and Methods
This study involved 30 Iraqi local goats within the anestrus season, spanning from June to November 2023, conducted at the animal field in Wasit governorate Iraq. The goats aged from 3 to 4 years and weighed between 20 and 25 kg. Heat detection was done two times a day by introducing the buck in a female goat herd and measurement of progesterone concentration to assure estrus. The progesterone concentration in goats of less than (1 ng/ml) were anestrus goats, also used transabdominal ultrasonography (Chison ECO2/ China) for pregnancy diagnosis in goats.
Experimental procedure
Seasonally anestrus, 30 Iraqi local goats were divided into 2 groups. The treated group (20 goats), were injected with the sulpiride (0.6 mg/kg) subcutaneously in the back side of the neck, two time a day (8 morning and 6 evening) until onset estrus, whereas the control group (10 goats), were administered normal saline.
Sulpiride was diluted in 1 ml (DMSO) and continued to 25 ml with normal saline daily. Blood samples were collected before treatment and monthly after the occurence of estrus. Estrus detection goats was two times at day (30 minutes morning and 30 minutes evening) by using 2 males. The estrus signs in goats was such as male-seeking behavior, urination, and stands to be mated.
Assessment of progesterone assay
The blood was collected via vena puncture and evacuated into gel tubes on days 0 before sulpiride treatment and monthly after estrus to determine progesterone concentration. Serum was collected after centrifugation with 3,000 rpm for 10 minutes and stored in eppendorf tube at −20oC until assays of hormonal concentrations. Serum kept in an epindroff tube at −20oC until analysis of hormonal concentrations by Abbott TECTplus immunoassay analyzer [11,12].
Ultrasonography
B-mode ultrasonography
All experimental goats were examined by Ultrasonography in pre insemination and post insemination. The examination procedure was by used ultrasonography B-mode diagnostic approach. The examination technique chosen depends on the pregnancy stage. Ultrasonography tool equipped with a 1st, 2nd, 3th, 4th and 5th months. Convex probe 4.5 MHz designed for applying transabdominal in Ultrasonography examination was including embryo, fetal head, vertebral column, extremities, thoracic, trunk, and placentome. During the transabdominal examination, animals were inspected while standing, probing the fleece less inguinal area caudo-ventral to the udder, and thereafter moving the transabdominal probe anterior as gestation progresses. The gel was placed on the tip of the transducer and the examinations were performed on longitudinal and transverse sections to identify the pregnancy details. The goat was designated pregnant by imaging apparent conceptus (elongated structure, anechoic) within a uterine fluid.
Statistical analysis
SAS (version 9.1) was used for the analysis of data. Two-way ANOVA and least significant differences post hoc test were completed to assess significant differences among means. p < 0.05 is considered statistically significant [13].
Results
Fifteen goats in the treated group exhibited signs of estrus, the induction rate of estrus was 75% and none of the animals demonstrated estrusin the control group goats. The duration of estrus was 33.5 ± 3.14 hours (Table 1).
Table 1.
Reproductive parameters responses to sulpiride (0.6 mg/kg) treatment in goats.
| No. goats | Incidence of estrus | Non estrus | Estrus duration (hour) |
|---|---|---|---|
| G1 (20) | 15/20 (75%) | 5 (25%) | 33.5 ± 3.14 |
| G2 (10) | 0 | 0 | 0 |
Progesterone was measured in the treatment groups significantly higher (p ≤ 0.05) at all months compared with the control group (Table 2).
Table 2.
The mean level (M ± SE) of progesterone concentrations (ng/ml) in pregnant goats with sulpiride treatment (0.6 mg/kg) at different gestational periods.
| Groups | Day (0) | Month | ||||
|---|---|---|---|---|---|---|
| 1st | 2th | 3th | 4th | 5th | ||
| G1 | 0.55 ± 0.1E | 9.1 ± 0.62C | 13.4 ± 0.7C | 25.1 ± 1.80B | 35. 2 ± 1.33A | 29.2 ± 1.04B |
| G2 | 0.53 ± 0.2E | 0.60 ± 0.13E | 0.54 ± 0.22E | 0.50 ± 0.3E | 0.55 ± 0.1E | 0.57 ± 0.4E |
Means with a different capital letter in the same column are significantly different (p < 0.05).
As depicted in the Table 2 the results of progesterone analysis during different months of pregnancy showed significant (p < 0.05) values during the fourth month of pregnancy which varied from another month but there was no significant differences between the first and second months of pregnancy.
The determination of foetus at an early stage of gestation was effectively accomplished using ultrasonography. The detection was made at 1st, 2nd, 3th, 4th, and 5th months post-conception. During the 1st month, 9 out of 15 goats were correctly diagnosed for pregnancy by ultrasonography and 2nd month 13 were confirmed to be pregnant and ultimately 13 pregnant ewes went to parturition (Table 2) and Figures 1–3.
The results of ultrasonography for pregnancy detection were significant in the treated group at 60% in the first month and 86% in the fourth month, respectively (Table 3).
Table 3.
The diagnosis of pregnancy by ultrasonography in treated group in Iraqi local goat.
| No. of goat estrus | 1st month | 2nd month | 3th to 5th month | Pregnancy % | Gestation length (days) |
|---|---|---|---|---|---|
| 15 | 9 | 13 | 13 | 13/15 (86%) | 152.32 ± 1.45 |
Discussion
There was a significant estrus induction in the anestrus goat after the treatment of sulpiride. This result agreement with the result of study Ali and Najlaa [14] reported significantly estrus induction by used sulpiride treatment. Also, the average duration of estrus was 33.5 ± 3.14 hours, this result agreement with the result Fatet et al. [15] reported the average duration of estrus was 36 hours. The used sulpiride in seasonally anestrus ewes occurs due to abrogation of the negative feedback of the gonadal steroids to the hypothalamo-pituitary–gonadal axis leading to GnRH secretion [8]. The sulpiride as non-hormonal treated was able to induce fertile estrus and induced ovulation in out-of-breed sheep [16]. This result of the study agreement with the study of local Small East African goats, the mean plasma progesterone concentration ranged from 2.6 to 10.8 ng/ml from conception to the mid-gestation [17]. The results in the present study appeared an increase in progesterone concentration during pregnancy, and the result showed that there were no significant differences (p ≤ 0.05) in progesterone level between the 1st and 2nd month. This result agrees with Musaddin et al. [18] who recorded progesterone level reached at its peak (24.2 ng/ml) toward the end of gestation and dropped to the lowest level (12.2 ng/ml) at the last 2 weeks of gestation the decline in the progesterone levels at the end of the 5th month of pregnancy in this study is due to approaching the time of parturition, this result in agreement with [19].
The results of ultrasonography for pregnancy detection were significant during the period of pregnancy diagnosis. This result agreement with Muhammad and Aziz [20] who reported the significance of ultrasonography for pregnancy detection in goats. The present study demonstrated that ultrasonography is an important instrument for early pregnancy diagnosis in goats in concurrence with earlier studies [21,22]. The gestation length was 152.32 ± 1.45 days and this result is in agreement with Mellado et al. [23] who reported the gestation length in goats was 151·4 ± 0·46 days and Praharani et al. [24] reported 150.25 ± 1.39 days of gestation for AngloNubian goats in Indonesia. The use of ultrasonography has shown varying results depending on the timing of pregnancy. Among the 15 goats studied, only 9 were accurately diagnosed as pregnant during the first month of pregnancy, which was detected by the embryonic mass in the pregnant uterus of goats (Fig. 1), and at the second month, the 13 goats were correctly diagnosed as pregnant, depending on appearance several gestational landmarks as placentome (Fig. 2), and at 3th to 5th months, the 13 goats was correctly diagnosed as pregnant, depending on the appearance of several gestational landmarks as fetal head, legs and rib (Fig. 3).
Figure 1.
The redz arrow refers to embryonic mass in pregnant uterus of goats.
Figure 2.
The red arrow refers to placentome.
Figure 3.
The red arrow refers to fetal head and blue arrow refers to legs and rib.
Conclusion
The using of sulpiride in Iraqi local goats successfully induced fertile estrus in the anestrus period. It could be an important non-hormonal intervention during seasonal anestrus for estrus induction in goats.
Acknowledgments
The authors thank Veterinary Medicine College/Tikrit University, Iraq.
Conflicts of interest
The authors have no conflicting interests.
Funding
This research received no external funding.
Authors contribution
All authors contributed equally to the work.
