This study was carried out to monitor serum cortisol level in pregnant ewes and comparing it with the non-pregnant values. Also, cortisol levels were monitored in single-fetus bearing and twin-fetus bearing ewes. This study was carried out during the breeding season on 31 pregnant and 5 non-pregnant ewes. Pregnancy and fetal numbers were determined through transrectal ultrasonography. Blood samples were collected every two weeks starting at day 30 of pregnancy until day 135 of pregnancy. Blood samples were collected in parallel from non-pregnant ewes as a control group. Cortisol was measured using ELISA.The results showed that serum cortisol levels increased gradually in pregnant ewes until day 90 of pregnancy reaching the highest level at day 135. Serum cortisol level was 4.26 ± 0.16 ng/ml at day 135 of pregnancy, while its level in non-pregnant ewes was 1.85 ± 0.15 ng/ml. Cortisol level was little bit higher in primiparous than pluriparous ewes, however, the difference was not significant. Regarding the effect of fetal number on cortisol level, twin-fetus bearing primiparous ewes had the significantly highest level. In addition, twin-fetus pulriparous ewes had a higher cortisol level than single-fetus bearing ewes. In conclusion, cortisol level increased gradually during pregnancy until day 90 reaching the highest level at day 135 of pregnancy. In addition, cortisol level was significantly higher in twin-fetus bearing ewes than single-fetus bearing ewes. This indicates that twinning increases stress on the pregnant ewes especially in primipara which need more care and attention.

The objective of the present study was to treat ovarian inactivity in mares during the breeding season by using three protocols. Mares (n = 52) kept under field condition in the Green Mountain area, north of Libya were examined transrectally by ultrasound during the breeding season. They were assigned to have inactive ovaries which was confirmed by measuring serum estradiol and progesterone concentrations. Mares were treated with either PMSG/hCG (n = 32), PMSG alone (n = 10) or GnRH (n = 10). Estrus was detected by stallions and mares in estrus were allowed to be mated two times 2 days apart and examined for pregnancy by ultrasound one month later. The results showed that in the PMSG/hCG group, 19 (59.4%) mares out of 32 exhibited estrus, while 6 (60%) and 5 (50%) mares out of 10 exhibited estrus in PMSG and GnRH groups, respectively. Also the results showed that 16 mares (50.0%) ovulated in PMSG/hCG group compared with 4 mares (40.0%) in GnRH group. However, there was no ovulation in PMSG group. Conception rate was 37.0 and 30.0% in PMSG/hCG and GnRH groups, respectively. Hormonal analysis showed that estradiol and progesterone concentrations were basal at start of treatment. Thereafter, estradiol concentration increased dramatically during estrus in all treated groups. Moreover, progesterone concentration increased 10 days post-mating in PMSG/hCG and GnRH groups while still low in PMSG group. Finally, we conclude that PMSG/hCG and GnRH can be used to treat ovarian inactivity in mares and induce follicular growth and ovulation. On the other hand, we cannot recommend PMSG alone to treat ovarian inactivity in mares.

Zusammenfassung Gegenstand und Ziel: Untersuchungen zur Beeinflussung des Blutspiegels von Glukose und anorganischem Phosphat bei gesunden, laktierenden Kühen nach 5- und 20%iger Glukoseinfusion. Material und Methoden: Für den Versuch standen 10 gesunde, laktierende und nichtgravide, 3- bis 6-jährige Kühe der Rasse Deutsch Holstein mit einer Tagesmilchleistung von 20,3±2,7 Litern zur Verfügung. Den Tieren wurde vor, während sowie 0 und 60 Minuten nach der Infusion von 0,9%iger NaCl-Lösung, 5- oder 20%iger Glukoselösung Blut zur Bestimmung des Gehalts an Glukose und anorganischem Phosphat entnommen. Ergebnisse: Es konnte ein signifikanter Einfluss der Glukose infusion auf den Blutglukosespiegel der Kühe nachgewiesen werden. Nach Infusion von 1000 ml einer 20%igen Glukoselösung (200 g Glukose) stieg die Glukosekonzentration um durchschnittlich 13,26 mmol/l, nach Verabreichung von 1000 ml einer 5%igen Glukoselösung (50 g Glukose) um durchschnittlich 3,31 mmol/l. Kein signifikanter Zusammenhang ergab sich zwischen einer 0,9%igen NaCl-Infusion, 5- oder 20%igen Glukoseinfusion und der Blutkonzentration an anorganischem Phosphat. Schlussfolgerung: Eine Infusion von 1000 ml 5- oder 20%iger Glukoselösung bedingt keinen nachteiligen Abfall des Blutphosphatspiegels und eignet sich zur Verbesserung der Blutglukose versorgung der Kuh.