published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Background: Intrauterine Insemination (IUI)is one of the common first-line assisted reproductive technologies (ART) for couples suffering infertility. Controlled ovarian stimulation (COH) with clomiphene citrate (CC) or aromatase inhibitor (like Letrozole) is often used in adjunct to IUI to increase the pregnancy outcome. Both CC and letrozole can be given alone as a single ovulation induction agent or they can be combined with injectable gonadotropin for purpose of superovulation. Study objectives: To systematically review the efficacy and adverse outcomes of letrozole and CC for supervulation in infertility patients undergoing IUI. Method: Systematic review of pertinent randomised controlled trials (RCT) using the bibliographic databases EMBASE, PubMed, Cochrane, Medline (OVID), Academic Search Premier and CINAHL. References of selected articles identified were hand-searched for additional relevant citations. RCTs that have compared the pharmacological performance of CC and letrozole as a single agent or combination with equal dose of gonadotropins were included. Results: Ten published randomized controlled trials were included in this review. The mean age, infertility diagnosis and duration of infertility of the recruited participants were comparable. Pregnancy rate was found to be comparable in clomiphene citrate (CC) group and letrozole (L) group. Higher peak estrogen concentration and greater number of dominant follicles were reported in CC group. Endometrial thickness was found significantly greater in L group. Adverse outcomes of rate of miscarriage, multiple pregnancies, ectopic pregnancies, OHSS and fetal anomalies were not significantly different between the two intervention groups. Conclusion: Letrozole and CC, considered equally patient-friendly agent due to oral route administration. Both agents achieved similar pregnancy rates without any increased risk of adverse events in either group. Letrozole can be used as alternative first-line OI agent to CC in reproductive treatments. Drug selection for patients should be done according to the cost effectiveness, duration of therapy, characteristics and compliance of patients. / published_or_final_version / Public Health / Master / Master of Public Health

Thesis (MTech. degree in Agriculture.)--Tshwane University of Technology, 2011. / There is limited information on semen characterisation and fertility rate of unimproved indigenous goat following cryopreservation. The aim of the study was to characterise semen, evaluate raw and frozen-thawed semen and test the fertility rate of frozen-thawed semen.

No description available.

Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, 1991. / Includes bibliographical references (leaves 274-316).

Thesis (doctoral)--Universität, Mannheim, 2007. / Description based on print version record. Includes bibliographical references (p. [231]-249).

Tierärztl. Hochsch., Diss., 2004--Hannover.

No description available.

No description available.

Doctor of Philosophy / Department of Animal Sciences and Industry / Jeffrey S. Stevenson / Four experiments were conducted in beef cows to determine factors that increased the probability of pregnancy per AI when cows are inseminated by appointment. Cows in all experiments were inseminated after a 7-d CO-Synch + CIDR program (100 μg GnRH [2 mL Factrel, Pfizer Animal Health, Whitehouse Station, NJ] 7 d before 25 mg PGF₂[subscript]α [d 0; 5 mL Lutalyse; Pfizer Animal Health]). Experiment 1 compared 1 vs. 2 inseminations and GnRH injection times at 60 and 75 h after the CO-Synch + CIDR program. Delaying AI until 75 h, according to interpretation of estrus-detection patches, for cows not in estrus by 60 h after CIDR insert removal increased (P < 0.05) pregnancy risk (PR) compared with cows not in estrus and inseminated at 60 h (51.4 vs. 41.7%), respectively. The necessity of GnRH injection concurrent with AI was tested in experiment 2. Cows displaying estrus by 65 h that were injected with GnRH had similar PR to cows in estrus and not treated with GnRH (61.9 vs. 60.4%), respectively. Cows in experiment 2 that did not display estrus, but were treated with a GnRH injection at 65 h and then inseminated at 84 h after CIDR insert removal had increased PR compared with similar cows not treated with GnRH (33.4 vs. 15.0%; P < 0.01), respectively. Experiments 3 and 4 were observational studies conducted to determine if blood metabolites glucose and beta-hydroxy butyrate (BHB experiment 3), or physical body and blood metabolites, (glucose, BHB, non-esterified fatty acids [NEFA], blood urea nitrogen [BUN], body weight, rump fat [RF], or BCS; experiment 4) were indicative of future reproductive success in suckled beef cows enrolled in a timed AI program. In experiment 3, plasma glucose concentration 10 d before AI was lesser (P = 0.01; 52.2 vs. 56.9 mg/dL) and serum BHB concentration was lesser (P < 0.01) in cows that became pregnant 35 d after timed AI than for cows that did not become pregnant (600 vs. 690 μM), respectively. Experiment 4 identified relationships between indicators and reproductive success including the finding that serum NEFA concentration 2 to 4 wk before AI is negatively correlated (P < 0.05) with PR to AI.