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The study investigated the efficacy of fetal heart diameter for estimating gestational age by using transrectal ultrasonograph. For this purpose, two experiments (two stages of study) were performed on 36 fat-tailed sheep. In the first experiment, when the pregnancies had been detected 30 days after breeding (day 0), fetal heart, biparietal and trunk diameters were measured at 15-day intervals between days 40 and 100 of pregnancy to compare the estimated and actual gestational ages in 28 ewes. In the second experiment - a blind study - gestational ages were estimated at unknown ages of pregnancy by the operator in 8 ewes. There were positive correlations (p < 0.01) between the estimated and actual gestational ages determined by fetal heart, biparietal and body trunk diameters in stage I and stage II of the study, respectively (r = 0.99, r = 0.99; r = 0.99 and r = 0.89, r = 0.91, r = 0.97). In conclusion, transrectal ultrasonographic examination was reliable tool to estimate gestational age between days 40 and 100 of pregnancy, and estimatiing gestational age by fetal heart diameter was as reliable as that estimated by biparietal and trunk diameters.
The study was carried out during April and May 2006, on thirty-eight 15 - 23-month-old Holstein heifers with inactive ovaries, which were selected from a private dairy herd with 300 heifers. The heifers were randomly distributed into two groups: norgestomet group (n=29), and a control group (n=9). In the norgestomet group, silicone ear implants containing 6 mg of norgestomet were implanted, and a solution containing 3 mg of norgestomet and 5 mg of oestradiol valerate was injected intramuscularly. The silicone implants were removed 11 d later, and the heifers were continuously observed for signs of oestrus for three days. The heifers were inseminated 48 and 78 h after the removal of the implants, and after the first insemination they were treated with 50 µg of GnRH analogue. The rate of the induced oestrus was 86.2% (25/29) and 0% (0/9) in norgestomet and control groups, respectively. The pregnancy rate was 48.2% (14/29) and 0% (0/9) in norgestomet and control groups, respectively. Our results showed that fertile oestrus can be stimulated successfully in post-pubertal heifers with inactive ovaries by a norgestomet treatment, and-successful pregnancy rate can be obtained by a fixed-time insemination during this oestrus.
The aim of this study was to evaluate the accuracy of the ECF test for detecting the pregnancy status and embryonic mortality and to compare the reliability of ECF test from among ultrasonography and serum progesterone level. In this study, two groups were designed: the study group (n = 15) and control group (n = 9). All cows were observed for estrus activity four times daily. Cows in the study group were inseminated. After insemination, at the 7, 20, 30 and 45th days ECF test and ultrasonographic examination were applied to check the pregnancy status. Cows in the control group were not inseminated and examination procedure was performed like in the study group. Twenty days after insemination, pregnant positive cows that had been determined by ultrasonography were designated the study group. Twenty days after insemination, ECF test were applied and progesterone levels were determined in the serum samples obtained from pregnant positive cows. Fifteen cows in the study group were checked 20 days after insemination and determined pregnant. Their pregnancy status was confirmed 20 days after insemination by using ultrasonography. In the 30th and 45th days ultrasonography was repeated, after which 13 cows were determined pregnant. In the serum of these two cows progesterone levels fell under 2 ng/ml. However, in the 20th day these cows’ progesterone levels was higher than 2 ng/ml, in two cows embryonic death occurred. In cows which were determined as pregnant by ultrasonography at the 20th day, the ECF test was applied at the 7th day and 10 cows from this group had a positive reaction (66.7%). Test specificity, PPV and NPV results were 44.4%, 66.7% and 44.4% respectively; at the 20th day the ECF test was positive for 9 cows (60%), specificity, PPV and NPV results were 33.3%, 60.0% and 33.3%; at the 30th day, the ECF test was positive for 12 cows (92.3%), test specificity, PPV and NPV results were 45.5%, 66.7% and 83.3%; at the 45th day, 10 cows (76.9%), test specificity, PPV and NPV results were 54.5%, 66.7% and 66.7% respectively. Between the study groups, the ECF test accuracy at the 7th and 20th days were found lower than at the other days. The test’s accuracy was determined the highest at the 30th day (70.8%), and the lowest at the 20th day (50%). The results show that ECF test is an unreliable method for pregnancy diagnosis and for determining embryonic death in dairy cows and these data indicate that the current ECF test cannot accurately identify the nonpregnant cows.
Efficacies of hCG and GnRH with respect to follicular diameter in Cosynch protocol were investigated. Lactating cows (n=119) received injections of GnRH and PGF₂ₐ 7 d apart. Norgestomet ear implant was inserted at GnRH administration and removed prior to PGF₂ₐ injections. Presence of the corpus luteum (CL) at GnRH and PGF₂ₐ injections, and diameter of preovulatory follicle [small (SPF) <8 mm or large (LPF) ≥8 mm] at PGF₂ₐ were determined with transrectal ultrasonography (USG). The animals were randomly treated with GnRH (0.01 mg; GPG, n=62) or hCG (1,500 IU; GPH, n=57) at timed artificial insemination (TAI) 56 h after injection of PGF₂ₐ. Pregnancies were diagnosed with USG 32-35 d after TAI. Pregnancies per TAI (P/TAI) were significantly (P<0.05) lower in GPH cows (28.1%; 16/57) compared to those in GPG animals (46.8%; 29/62). P/TAI with respect to follicular size did not differ between GPG and GPH cows, although P/TAI was numerically higher in LPF (30.0%; 15/50) than in SPF (14.3%; 1/7) in GPH cows. P/TAI in cows without CL at PGF₂ₐ was 2.5 (1.0-6.7) times higher (P<0.01) in GPG (20.0%; 3/15) compared to GPH (10.5%; 2/19). In conclusion, use of hCG in milieu of the second GnRH in Cosynch+progesterone insert protocol did not have any advantage in lactating cows.
The reversibility of anoestrus caused by long-acting GnRH analogue (deslorelin), and the effectiveness of GnRH analogue to induce standing oestrous, and in consequence to the retardation of breeding season, was investigated. During the transition period, 26 fat tailed breed ewes were randomly divided into 3 groups. GnRH analogue Ovuplant and Suprelorin were inserted under the neck skin in group I (n=7) and group II, respectively. No administration was applied in group III (control group, n=10). Suprelorin was removed 60 d after the implant's insertion. The initiation of sexual activities based on the day of progesterone increase, and the first standing oestrous were 12.9±1.86, 34.7±9.69, 81.9±6.31, and 27.3±1.94, 48.3±9.24, 96.9±5.76 in control, Ovuplant and Suprelorin was administered to groups; respectively (P<0.001). In conclusion, deslorelin administration resulted in reversible anoestrus in ewes. During the 60 d experimental period, Suprelorin effectively suppressed sexual activity; therefore, Suprelorin could be used to delay the breeding season.
An eight-year-old German shepherd crossbreed clinically healthy bitch was ovariohysterectomized on the owner's request. The ovariohysterectomy operation was performed on the left flank area, under general anaesthesia. In both uterine horns, diffuse 0.1-3 cm in length cystic structures filled with serous fluid were detected during macroscopic examination. Histopathological examination of the uterus revealed that the pathological tissue was diffuse cystic lymphangiectasia.
The effects of levamisole, as an anthelmintic or immunomodulator, on pregnancy were investigated in ewes. Immunomodulatory and anthelmintic doses of levamisole and physiologic saline were injected on days 0 (oestrus), 7, 14, and 21 in group 1 (immunomodulatory dose; n=7), group II (anthelmintic dose; n=6), and group III (control; n=6), respectively. The first service pregnancy rate, tended to be lower (P<0.06) in group I (28.6%) compared to that of groups II (83.3%) and III (83.3%). Plasma progesterone (P₄) concentration was significantly higher (P<0.05) in group II compared to that of group III on day 3, and there was a treatment x day interaction (P<0.05). No effect of levamisole treatments on plasma P₄ concentrations was detected once pregnancy was established. There was a numeric decline in plasma cholesterol concentrations in group II, compared to group I or III on day 3. In conclusion, levamisole as an immunomodulator is detrimental for the establishment of pregnancy, possibly by stimulating general and intrauterine immunity.
The aims of this study were to compare two methods of estrus synchronization and to evaluate the effectiveness of the PMSG treatment combined with P4 application. Fifty non-lactating seasonal anestrus fat-tailed ewes were randomly assigned into five groups. The controlled internal drug release devices (CIDR) were applied during day 14 in group I and in group II. Progesterone impregnated sponges were applied during day 14 in group III and in group IV. And then 500 IU PMSG was injected in group I and III i.m. intravaginal devices removed. Ewes in group V served as controls. There was no difference between the groups in the peak value of LH and LH surge. Although LH surge was seen in the control groups 5 sheep, none of the control ewes expressed estrus. Different progestagen treatments have no different results when they are evaluated in terms of the success of the estrus synchronization. PMSG application, after P4 treatment, increased the success of the synchronization.
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