The study was carried out at Maryout Research Station located 34 Km west of Alexandria that belongs to the Desert Research Center (DRC), Ministry of Agriculture and Land reclamation, and at the Department of Animal Production, Faculty of Agriculture, Alexandria university. The aim of the study was to improve the reproductive performance of she-camels under semi-arid conditions by using different regimens of progestins on controlling and synchronizing the ovarian activity and AI program based on real-time ultrasonography of ovarian structures The efficiency of hormonal synchronization of estrus and induction of ovulation in addition to the changes in some blood biochemical constituents during the course of synchronization of ovulation and early days of pregnancy were determined.
Eighteen mature one-humped she-camels, aging between 7 to 10 years, with an average body weight of 450 ± 0.2 kg were used in this study from November 2012 to March 2013. Animals were randomly divided into 3 groups of 6 animals each, the first group served as control and received no treatment, while the second group received (0.5 gm/h/day) melengestrol acetate (MGA) orally for 10 consecutive days and finally the third group was fitted with controlled internal drug release (CIDR, 1.38 gm) device for 10 consecutive days. On day nine of progesterone treatment (CIDR, MGA), each animal was injected i.m. with 500 μg PGF2α and on day ten, upon CIDR withdrawal and MGA treatment was stopped, each animal was injected i.m. with 3000 IU PMSG. Immediately before insemination, each female received 5000 IU i.m. injection of hCG to induce ovulation. Monitoring the ovarian activity was done 3 times after 4 days from CIDR removal or MGA withdrawal from feed to determine the appropriate time for insemination according to the size of the dominant follicle. In addition, the uterine contents were scanned on days 18, 30, 60 and 90 from AI for early pregnancy diagnosis. Blood samples were collected from all animals before and after supplementation of melengestrol acetate (MGA) and CIDR in on days (day 0 is the day CIDR-in) and days 10 is the day of CIDR-out and day 15, 17, 20 before AI). In addition, blood samples were collected from she-camels on days 18, 30, 60, 90 after AI.
The obtained results can be summarized as follows:
1. Hormonal treatment had no effect on either total number of follicles or size of the dominant follicles, however days of synchronization had significant (P < 0.01) effect on the diameter of the dominant follicles in she-camels. The diameter of the dominant follicle was largest in MGA and CIDR groups on day 7 after CIDR removal and MGA withdrawal (1.1 and 1.2 cm) respectively, this was equivalent to day 17 for control group (1.1 cm),while the lowest diameter was recorded day 10 in all groups.
2. The overall mean of serum progesterone concentration of the CIDR group (4.30 ng/ml) was significantly greater (P < 0.01) than those of control and MGA groups (0.47 and 0.80 ng/ml, respectively). Also, serum progesterone showed significant increase during days of synchronization (P<0.01) in CIDR group being (11.9 ng/ml) on day two, then the concentration declined to (3.58 ng/ml) on day 10 (day of CIDR removal), and decreased to a basal level of (0.73 ng/ml) on day 20, while in the control group P4 concentration was (0.35 and 0.93 ng/ml) for the MGA group.
3. The overall means of serum estradiol 17-β concentrations were not significantly different among MGA and CIDR groups (44.56 and 47.31 pg/ml), respectively compared with the control group (54.19 pg/ml), during the synchronization period. Nevertheless, the treated groups that received the progestin treatments had lower estradiol 17-β concentrations on days 4, 6, 8 and 10 compared to the control.
4. Numerical increases were observed in single ovulation and ovulation rate (%) in MGA group 83.33% and 66.67% compared to CIDR group (66.66% and 33.33%) respectively. However the CIDR group tended to have more multiple-ovulation (33.33%) than the MGA group (16.67%). Also the MGA and CIDR treatments had slight different conception rates (66.67%) and (50%), respectively.
5. The results revealed no-significant effect of treatment on all the studied hematological parameters [hemoglobin (Hb), packed cell volume (PCV), red blood cell counts (RBCs), white blood cells (WBCs), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and mean corpuscular volume (MCV)] in she-camels during synchronization period. However, all hematological parameters were affected (P < 0.01) by days of synchronization except Hb concentration and WBCs counts.
6. Serum total protein, albumin, cholesterol, high density lipoprotein and aspartate aminotransferase concentrations were not significantly affected in MGA or CIDR groups as compared to the control group, while, days effect was significantly observed (P < 0.01) on serum concentrations of albumin and aspartate amino- transferase enzyme activity.
7. Numerical increase in serum urea nitrogen was noted in the CIDR group (20.12 mg/dl) compared with the control and MGA groups (18.52, 18.11 mg/dl) respectively. There was a marked effect of days (P<0.01) on serum urea concentrations, where the least serum urea concentration (17.58 mg/dl) was recorded at day 6 compared to other days.
8. Serum glucose concentration was not significantly affected in the MGA or CIDR groups compared to the control. However, in the MGA and CIDR groups serum glucose increased to its highest (P <0.01) on days 17 and 20 compared to the control and to other previous days.
9. The level of serum alanine aminotransferase concentrations were greater (P < 0.05) in the CIDR (5.80 IU/L) and MGA (5.72 IU/L) groups than in the control group (5.13 IU/L) as well as days.
10. The results revealed no significant effect of treatment on serum mineral concentrations of calcium (Ca), phosphorus (P) and sodium (Na) in she-camels during synchronization period. However, There was a marked effect of days (P<0.05) on serum phosphorus where the highest value was recorded on day 20 in the MGA and CIDR groups compared to control. However, serum potassium (K) concentrations were significantly higher (P < 0.01) in the CIDR group (3.84 mEq/l) compared with control and MGA (3.42 and 3.46 mEq/l) groups respectively. Days effect (P < 0.05) was recorded on overall mean serum K concentrations, with day 20 recorded highest overall serum k concentrations (4.34 mEq/L) compared to previous days.
11. The results also clarified that overall means of serum progesterone concentrations were significantly higher (P < 0.01) in pregnant she-camels (10.72 ng/ml) compared with the non-pregnant ones (0.52 ng/ml). Serum progesterone concentration increased in pregnant animals increased from (5.98 ng/ml) on day 18 following insemination, and reached the highest level on day 60 of pregnancy (18.05 ng/ml) then declined on day 90 (12.00 ng/ml). Also, there were significant interaction
(P<0.05) in progesterone among days of pregnancy concentrations. Serum progesterone concentration for non-pregnant she-camels remained at a basel level of (0.66, 0.34, 0.57 and 0.52 ng/ml) on days 18, 30, 60 and 90.
12. Numerical increase was observed in estradiol 17-β concentrations in non-pregnant animals (40.39 pg/ml) as compared with pregnant she-camel ones (27.53 pg/ml).
13. Serum total protein, albumin and cholesterol were not significantly affected by pregnant status, or days of pregnancy.
14. The results showed that overall mean serum urea concentration was greater (P < 0.05) in the pregnant she-camels (23.18 mg/dl) compared with the non-pregnant animals (19.79 mg/dl). Also days of pregnancy showed a significant (P < 0.01) effect on serum urea nitrogen concentrations, and increased from (16.2 mg/dl) on day 18 to (33.81 mg/dl) on 90d of pregnancy.
15. Data also indicated that overall means of serum glucose concentrations were not different between pregnant and non-pregnant she-camels, while days had a significant (P < 0.01) effect. Days 18 and 30 had elevated serum glucose concentrations compared to days 60 and 90 after insemination in both pregnant and non-pregnant animals.
16. The results showed that overall mean serum of high density lipoprotein concentrations was greater (P < 0.05) in the pregnant (21.17 mg/dl) compared with the non-pregnant she-camels (13.41 mg/dl).
17. Serum aspartate aminotransferase concentrations were greater (P < 0.05) in pregnant (25.75 IU/L) than the non-pregnant she-camels (17.52 IU/L), while serum alanine aminotransferase concentrations were not significantly affected by pregnancy (12.77 and 11.13 IU/L) respectively.
18. There were no significant effects of pregnancy status on serum mineral concentrations [phosphorus (P), sodium (Na) and Potassium (K)] in she-camels during 90 days after insemination. However serum calcium concentration was greater (P < 0.05) in the pregnant she-camels (10.06 mg/dl) compared with the the non-pregnant (7.85 mg/dl). However, all mineral concentrations were not affected by days of pregnancy except P concentration.