Comparison of pregnancy-associated glycoprotein and oestrone sulphate concentrations in recipient goats of in vitro produced embryos cultured in synthetic oviduct fluid (fresh and vitrified) or co-cultured with goat epithelial oviduct cells (vitrified)

in Reproduction in Domestic Animals (2008), 43(4), 55

Effects of ovum pick-up frequency and FSH stimulation: a retrospective study on seven years of beef cattle in vitro embryo production.

in Reproduction in Domestic Animals (2008), 43(2), 239-245

The aim of this retrospective study was to compare the number of follicles, cumulus oocyte complexes (COCs) and cultured In Vitro Produced (IVP) embryos obtained from 1396 non-stimulated Ovum Pick-up (OPU ... [more ▼]

The aim of this retrospective study was to compare the number of follicles, cumulus oocyte complexes (COCs) and cultured In Vitro Produced (IVP) embryos obtained from 1396 non-stimulated Ovum Pick-up (OPU) sessions on 81 donor animals in a twice weekly OPU scheme. Results were obtained from 640 sessions following FSH-LH superstimulation, on 112 donors subjected to OPU once every 2 weeks. The stimulation protocol started with the insertion of an ear implant containing 3 mg norgestomet (Crestar, Intervet, Belgium) 8 days before puncture (day -8). The dominant follicle was ablated by ultrasound-guided follicle puncture on day -6. On day -3 and day -2, cows were injected with FSH (Ovagen, ICP) twice daily (8 am to 8 pm), i.e. a total dose of 160 mug FSH and 40 mug LG per donor per stimulation cycle. Animals were punctured 48 h after the last FSH injection (day 0). Progesterone implants were removed the next day. Stimulated donor cows were treated with this protocol at 14-day intervals. Follicles were visualized with a Dynamic Imaging ultrasound scanner, equipped with a 6.5 MHz sectorial probe. Follicles were punctured with 55 cm long, 18 gauge needles at an aspiration pressure corresponding to a flow rate of 15 ml/min. Cumulus oocyte complexes were recovered and processed in a routine IVF set-up. Results demonstrate that, expressed per session, FSH stimulation prior to OPU increases production efficiency with significantly more follicles punctured and oocytes retrieved. However, when overall results during comparable 2-week periods are considered (four non-stimulated sessions vs one stimulated), more follicles are punctured and more oocytes are retrieved using the non-stimulated protocol. No significant differences in the number of cultured embryos could be detected, indicating that FSH/LH stimulation prior to OPU might have a positive effect on in vitro oocyte developmental competence as more embryos are cultured with less, presumably better-quality, oocytes [less ▲]

No effect of parity on concentrations of bovine pregnancy associated glycoprotein (PAG) measurement by radioimmunoassay.

in Reproduction in Domestic Animals (2008), 43(Suppl 5), 90

Pregnancy diagnosis in ruminant species.

in Reproduction in Domestic Animals (2008), 43(Suppl 5), 104

Influence of continuous breeding goats on return to cyclicity in seasonal breeding goats

in Reproduction in Domestic Animals (2007), 42

The boer goats which originated from the South African Republic are continous breeding animals when kept in the northern hemisphere and they kidd three times in 2 years. In this study, a mixed herd was ... [more ▼]

The boer goats which originated from the South African Republic are continous breeding animals when kept in the northern hemisphere and they kidd three times in 2 years. In this study, a mixed herd was monitored to determine whether boer goats could induce return to cyclicity in sesonal breeding goats. All goats (n = 20) were pluriparous and kidded during January and February. During January a mixed group was formed (10 boer goats kept together with 10 domestic breed goats). At the same time a group of domestic breed goats (n = 12), kept in the same manner, 40 km away from the experimental group was used as controls. Blood samples were collected every 72 h to determine level of progesterone in both herds. Goats were monitored at the same time to observe for signs of oestrus. Progesterone concentrations in sera samples were determined using a RIA method. Data were analysed by ANOVA using Statistica software. We observed visual oestrus in all boer goats and in eight domestic breed goats from the mixed group during March and April. Progesterone concentrations confirmed the presence of functional corpora lutea between two visual cycles in these animals. No visual oestrus or increases in progesterone were observed in the control group of goats. In conclusion, continuous breeding boer goats induced oestrus in 80% (n = 8) of seasonal breeding goats when kept in a mixed herd. [less ▲]

Comparison of five radioimmunoassay systems for PAG measurement: Ability to detect early pregnancy in cows

in Reproduction in Domestic Animals (2007), 42(4), 433-440

This study was conducted to describe the minimum detection limit, reproducibility, accuracy, specificity and parallelism of different pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA) systems ... [more ▼]

This study was conducted to describe the minimum detection limit, reproducibility, accuracy, specificity and parallelism of different pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA) systems: RIA-497, RIA-706, RIA-780, RIA-809 and RIA-Pool. Their ability to distinguish between non-pregnant and pregnant females at day 30 after artificial insemination (Al) was investigated. The antisera were raised in rabbits against different PAG preparations. All RIA systems proved to be sensitive, repeatable and accurate for measuring PAG concentrations. The dilutions of plasma samples taken at an early stage of pregnancy were found to be parallel to the standard curves. No cross-reaction was observed with different carbohydrates, either with Pregnant Marc Serum Gonadotropin (PMSG) or human Chorionic Gonadotropin (hCG). The concentrations of PAG in pregnant females at day 30 after Al were shown to be higher with the use of antisera R#706, R#780, R#809 and Pool when compared with antiserum R#497. All the RIA systems gave 100% sensitivity and negative predictive values. On the other hand, the use of antisera R#780 and R#809 resulted in lower specificity and positive predictive values. The present study clearly shows that the ability of PAG-RIA systems to diagnose pregnancy specifically at day 30 after Al can be improved by using a combination of antisera raised against different forms of PAG. [less ▲]

Breed-cross pregnancies increased plasmatic pregnancy-associated glycoprotein (PAG) concentration in pregnant Neospora-seropositive dairy cows

in Reproduction in Domestic Animals (2006), 41(suppl 2), 112

Effects of a single injection of a progesterone receptor antagonist during the third month of gestation in sheep

in Reproduction in Domestic Animals (2006), 41(4), 310

Effect of the type and number of prostaglandin treatments on corpus luteum, the largest follicle and progesterone concentration in dairy cows

in Reproduction in Domestic Animals (2005), 40(5), 436-442

Lactating dairy cows (n = 72) with a mature corpus luteum (CL) (diameter of >= 17 mm) determined by ultrasonography and having a follicle with a diameter of >= 10 min were randomly assigned to four groups ... [more ▼]

Lactating dairy cows (n = 72) with a mature corpus luteum (CL) (diameter of >= 17 mm) determined by ultrasonography and having a follicle with a diameter of >= 10 min were randomly assigned to four groups. Cows were treated with cloprostenol i.m. once or twice, or with dinoprost i.m. once or twice with an 8-h interval. The ovaries of each cow were scanned daily by transrectal ultrasonography to measure the changes in the areas of CL and the largest follicle and to determine the occurrence of ovulation. Oestrus was verified twice daily. In addition, blood sample was withdrawn from each cow daily for measuring progesterone (P4) concentrations. Significant decreases in the percentage changes relative to areas of CL and P4 concentrations or increases in the percentage changes in the area of the largest follicle on day 0 were detected in each group during the experiment. However, the type of the drug and the number of the treatments had no significant effect on those parameters. Cows ovulated with or without showing oestrus (group A) and cows exhibiting no oestrus and ovulation (group 13) were also evaluated. In contrast to the mean area of the CL and the mean concentration of P4 on day 0, the mean area of the largest follicles between, the two groups on day 0 differed significantly Significant decreases in the percentage changes relative to the area of the CL and P4 concentration or increases in the percentage changes relative to the area of the largest follicle during the experiment were detected in both groups; however, there were no group differences. Treatment of dairy cows with two injections of prostaglandins (cloprostenol or dinoprost) at an 8-h interval resulted in more cows being, observed in oestrus within 5 days after treatment and having significantly higher pregnancy rate than those treated with a single prostaglandin injection. [less ▲]

Embryonic signals and pregnancy diagnosis in ruminants

in Reproduction in Domestic Animals (2004), 39(4), 252