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Number of results: 6
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Abstract

Primiparous and multiparous lactating crossbred dairy cows with a mature corpus luteum and a follicle with >10 mm in diameter were treated with cloprostenol. Those cows that showed oestrus within 5 days after treatment were inseminated (Group P). The other cows (Group PG) were treated with GnRH 2 days after cloprostenol treatment and timed artificial insemination (AI) was performed on the consecutive day, or were inseminated (Group G) after detected oestrus and treated with GnRH immediately after AI. The control cows (Group C) after detected oestrus were only inseminated. All of the AIs using frozen semen were done between 6 and 7 a.m. while the ultrasonographic examinations after AI were performed between 4 to 6 p.m. The ovaries of each cow were scanned by means of transrectal ultrasonography from the day of AI until ovulation. Daily blood samples were collected for progesterone measurements. The ovulation and preg- nancy rates among the groups changed between 84.6% and 95.5%, as well as 44.4% and 60%, respectively, however the differences were not statistically significant. All the cows were evaluated according to date of ovulation after AI and the pregnancy rate was 55.4% (Group 1: ovulation occurred between AI and 9-11 h after AI), 54.5% (Group 2: ovulation occurred between 9-11 h and 33-35 h after AI) and 35.5% (Group 3: ovulation occurred between 33-35 h and 57-59 h after AI), respectively. There was a trend (P=0.087) for 2.2 greater odds of staying open among cows inseminated between 33 to 35 h and 57 to 59 h before ovulation compared to cows inseminated within 9 to 11 h before ovulation. If ovulation occurred before AI, the pregnancy rate was only 22.2%, therefore determination of optimal time for AI is of great importance.
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Abstract

The aim of the study was to investigate the influence of cystic ovarian follicles (COFs) occurring after puerperium on fertility and the effect of their treatment with progesterone releasing device on reproductive performance in dairy cows. The study was carried out in 3 herds of Polish Holstein-Friesian cows under herd health program. COFs were diagnosed by ultrasound above 60 days p.p. They were defined as follicular structures with a diameter > 2.5 cm in the absence of a corpus luteum at two repeated examinations at the 14-days interval. On the day of COF diagnosis blood samples were collected to measure progesterone (P4) concentration. On the basis of the wall thickness measurement and progesterone concentration at the first examination, the COFs were differentiated into follicular and luteal cysts. The experimental group consisted of 23 animals with COF. The cows were treated with PRID Delta (Ceva Animal Health, Poland), containing 1.55 g of progesterone, for 7 days. The cows without oestrus signs within 14 days after treatment were re-examinated. If COF persisted, the cows were treated again with PRID Delta. The treatment was repeated maximum three times. Fifteen cows with ovarian cysts were left untreated and served as a control group. The cows with COF were matched to healthy cows without COF. The cows with COF had worse fertility performances compared to cows without COF. There were significant (p<0.05) differences in conception rates, number of services per conception and days open between these groups. Compared with non-treated cows with COF, in cows with COF treated with PRID Delta conceptions rates and number of services per conception were similar, but the days open were significantly (p<0.05) lower in cows treated than in non-treated (183.3 days vs. 277.6 days). There were no differences in reproductive performances between the follicular and luteal cysts in treated and non-treated cows. In conclusion, the results of our study confirm the negative impact of COF after puerperium on fertility in dairy cows. Furthermore the results indicate the usefulness of PRID Delta for the treatment of COF occurring after the puerperium regardless of cysts type.
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Abstract

The aim of this study was to compare the efficacy of estrus induction and fertility by using subcutaneous melatonin (MEL, T1) and short-term intravaginal medroxyprogesteronacetate plus pregnant mare serum gonadotropin treatments (sMAP+eCG, T2) in ewes on seasonaly anestrus. In this study, 105 mature clinically healthy Kivircik ewes in anestrus season and 4 rams were used. After synchronization applications, ewes exhibiting estrus signs were hand-mated with rams known to be fertile. Blood samples were collected at different times in order to determine progesterone (P4) concentrations. Results showed that estrus manipulation protocols induced significant improvement in pregnancy rate. All the fertility results obtained with the sMAP+eCG or MEL groups were similar, in seasonal anestrus. The efficacy duration of P4 in the MEL group was longer than that in short-term progestagen group. Plasma P4 concentrations was significantly different between the first (I) and last (III) measurement days (p<0.01). Increase in P4 concentration in T2 group was faster than that in T1 group, and blood P4 concentrations at higher levels could successfully be achieved by using any of the protocols in this study during the seasonal anestrus. In conclusion, according to the results obtained, the hormone application groups received very high estrus response. In addition, the twin ratio was found to be higher in T1 group compared to those determined in the other groups (T2 and Control group). Furthermore, plasma P4 concentrations and high birth rates were obtained in ewes in T1 and T2 groups. These procedures can be considered a good alternative to traditional procedures due to its flexibility under field conditions.
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Abstract

To evaluate the role of preovulatory progesterone on canine sexual behavior and the course of proestrus and estrus, seven bitches in spontaneous cycles were treated with aglepristone for temporary elimination of progesterone action. Aglepristone was administered at the dose 10 mg/kg b.m., two times 24 hours apart, beginning in early proestrus when progesterone concen- tration was <0.5 ng/ml. Seven untreated bitches served as a control group. Reproductive sexual behavior (standing behavior, display vulva, tail deviation) was evaluated according to behavioral score. Cytologic, clinical and vaginoscopic examinations and progesterone measurements were used for the determination of proestrus and estrus and estimation of ovulation time. Although, a similar pattern and magnitude of sexual behavior were observed in both groups, the duration of a total reproductive behavior was significantly extended (28.71 ± 2.06 vs 17.00 ± 2.45, p <0.05) in experimental group; similarly, the length of cytologic estrus (23.86 ± 3.02 vs 11.14 ± 2.41, p <0.05) was prolonged in treated bitches. In contrast, ovulation rate, duration of proestrus did not differ between the groups (p >0.05). We conclude, that during the canine estrus cycle the preovulatory progesterone terminates the duration of reproductive behavior and cytologic estrus.
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Abstract

One of the effective reproductive management programs in dairy cattle is the accurate detection of pregnancy. A total of 204 non-descriptive cows were examined for pregnancy before slaughter in Sulaimani abattoir. Examinations were done by rectal palpation and enzyme-linked immunosorbent assay (ELISA) to measure the levels of progesterone and bovine pregnancy-associated glycoproteins (bPAGs) in their blood. Detection of a live conceptus in the uterus of slaughtered cows was used as the gold standard to determine the accuracy of the three pregnancy detection methods. The results showed that the accuracies of rectal palpation, progesterone assay, and bPAGs assay in the diagnosis of pregnancy were 87.2%, 84.8%, and 97.05%, respectively. The bPAGs assay scored the highest sensitivity (100%) for detection of pregnancy, followed by the progesterone assay (92.3%) and rectal palpation (84.6%). In addition, the specificity of the bPAGs assay was the highest (96.0%), while progesterone assay exhibited the lowest specificity (80.1%) and rectal palpation showed a specificity rate of (88.8%). In conclusion, the best method for the detection of either for early or late pregnancy in cows was the bPAGs assay, which gave the lowest number of false-positive and false-negative results.
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Abstract

Progesterone (P4) is responsible for the main reproduction processes. Concentration of P4 varies widely among different determination methods, and interpretation of these values may be difficult. The objective of the current study was to assess the agreement of three different enzyme immunoassays (ELISA) in relation to radioimmunoassay (RIA) of P4 concentration assessment of beef cow serum samples. Samples were collected randomly considering high (pregnant cows) and low (non-pregnant cows) P4 concentrations. Depending on the P4 assessment method, four groups were created as follows: Group 1 – direct samples assessed by ELISA, Group 2 – extracted samples assessed by ELISA, Group 3 – samples assessed by automated ELISA, and Group 4 – samples assessed by RIA. The mean progesterone concentration was 4.50 ng/mL, 1.24 ng/mL, 4.07 ng/mL and 4.39 ng/mL from Group 1 to Group 4, respectively. The mean difference (MD) between Group 1, Group 2 and Group 3 individually compared with Group 4 was −0.10 ± 1.24 ng/mL, 3.15 ± 3.58 ng/mL and 0.33 ± 1.42 ng/mL, and the 95% confidence interval (CI) for the differences (s) was from −0.99 to 0.78 ng/mL, from 0.59 to 5.71 ng/mL, and from −0.69 to 1.34 ng/mL, respectively. The confidence interval for the lower and upper limit of the agreement ranged from −4.12 to −1.05 ng/mL and from 0.84 to 3.91 ng/mL between Group 1 and Group 4, from −8.45 to 0.42 ng/ mL and from 5.88 to 14.75 ng/mL between Group 2 and Group 4, from −4.29 to −0.76 ng/mL, and from 1.41 to 4.94 ng/mL between Group 3 and Group 4. Our findings show that the best agreement with RIA was observed for Group 1 and Group 3, while the agreement in the extraction method was least accurate.
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