BACKGROUND: This study aims to determine whether pre or post-processing semen parameters obtained during intrauterine insemination (IUI) predict pregnancy when controlling for confounding effects.
METHODS: A prospective cohort study of 2231 semen analyses was conducted at McGill University of IVF center. Any couples who underwent IUI with partner sperm, over a 2.5-year period, were included. Controlled ovarian stimulation was done with Clomiphene Citrate, Letrozole, or Gonadotropins. Statistical analysis was performed using t tests, two types of stepwise logistic regression, and stepwise discriminant analysis. A comparison of pre and post-processing semen parameters was undertaken to determine the probability of pregnancy.
RESULTS: There were significant differences between pregnant and non-pregnant women in post-processing concentration (P=0.043), post-processing total motile sperm count (TMSC) (P=0.049), and post-linearity (P=0.012). However, when variable out-of-the-equation logistic regression or discriminant analysis, which controls for confounding effects between variables, were used, the findings were no longer significant. It was statistically proven that when a variable in the equation logistic regression was employed, post-processing concentration (P=0.005) and post-processing TMSC (P=0.009) remained reliable predictors of pregnancy.
CONCLUSIONS: Two of three prediction models suggested that TMSC\'s relationship with pregnancy is due to confounding factors. One model maintained the validity of the TMSC. While TMSC has always been studied as an important predictor of insemination pregnancies, this finding may be due to confounding effects between semen parameters and therefore requires further investigation as to this relationship.

BACKGROUND: Thin endometrium in infertile female patients has always been a clinical challenge for the treating reproductive physicians.
OBJECTIVE: This study aimed to evaluate the effect of intrauterine instillation of autologous platelet-rich plasma on endometrial thickness and vascularity in infertile female patients with thin endometrium undergoing ovarian stimulation with intrauterine insemination.
METHODS: This prospective randomized control study included 120 women undergoing ovarian stimulation with intrauterine insemination, aged between 21 and 37 years, with persistent thin endometrium (<7 mm) on ≥1 cycle in previous ovarian stimulation cycles, even after conventional treatment with estradiol valerate. The women were randomly assigned to study group A and control group B. Baseline endometrial thickness and endometrial vascularity were noted. Intrauterine instillation of autologous platelet-rich plasma was done on the day of trigger in group A, whereas estradiol valerate was given in group B. Another evaluation of endometrial parameters was done on the day of intrauterine insemination. The cycle was repeated for 3 cycles or until the pregnancy was achieved, whichever occurred earlier. Parameters were noted for both groups. Primary outcomes were the change in endometrial thickness and endometrial vascularity. Secondary outcomes were positive pregnancy rate and clinical pregnancy rate.
RESULTS: In group A, mean pre-platelet-rich plasma endometrial thickness was 4.66±0.79 mm, which significantly increased to 7.47±0.85 mm after platelet-rich plasma instillation (P<.05) after 3 cycles. This increase was significantly greater than that observed in group B. There was significant increase in endometrial vascularity in group A compared with group B (P<.05). The positive pregnancy rate and clinical pregnancy rate in group A were 23.73% and 18.64%, respectively, and significantly higher than those in group B.
CONCLUSIONS: Autologous platelet-rich plasma is a promising, easily procurable, and novel option for management of infertile females with thin endometrium not responding to conventional treatment. Using it in intrauterine insemination cycles can reduce costs and psychological burden of this subgroup of women by reducing the need for resorting to advanced options such as in vitro fertilization and surrogacy.

Low fertility rates in lactating dairy cows as well as restricted availability of semen doses of young bulls with high genetic merit are two major problems in the reproduction of dairy cows. By using liquid semen (LS), the number of doses per ejaculate can be increased. One of the challenges of optimizing the reproductive performance of dairy cows is the phenomenon of variable estrus lengths. The objective of this study was to determine whether the use of LS affects pregnancy outcome of dairy cows with delayed ovulation, when compared with frozen semen (FS). A randomized controlled clinical trial was implemented. In a split-sample procedure, 131 ejaculates were processed into LS (Caprogen, LIC, New Zealand) and FS (BioXcell, IMV, France). Both semen types of each ejaculate were inseminated under the same field conditions to cows showing natural or induced heat. Cows and semen type were allocated according to the last digit of the cows identification number (even = frozen semen, odd = liquid semen). Inseminations (n = 667) were conducted after localization of the pre-ovulatory follicle. Determination of ovulation was performed 24 h post AI per transrectal ultrasonographic examination. Ovulations were classified as delayed when the pre-ovulatory follicle was still present at ovulation control. The prevalence of delayed ovulations was 25.2%. Data of 667 inseminations were analyzed with a generalized linear mixed model including semen type (P = 0.016), parity (P = 0.014), backfat thickness (P = 0.006), estrus induction (P = 0.010), ovulation (P = 0.265) and the interaction term \'semen type by ovulation\' (P = 0.094). Overall, a higher pregnancy per AI (P/AI) of LS (45.4%) than P/AI of FS (33.7%) was found. In cases of delayed ovulations, use of LS resulted in higher P/AI (46.8%) compared with FS (27.7%; P = 0.017). We concluded that the fertilizing capacity of LS in prolonged intervals from AI to ovulation might be greater when compared with FS and could be an efficient tool to improve fertility of lactating dairy cows with delayed ovulations.

Retained cytoplasmic droplets (CD) provide the most abundant sperm abnormality in boar and reduce fertility. It is still unclear as to whether high CD rates in semen portions are compensable. The aim was to explore the impact of CD in relation to quantitative and qualitative sperm traits on fertility performance of sows. Retrospective data analysis of 1497 inseminations was performed. Ejaculates (n = 260) were assigned to three groups with low (<10%), medium (≥10% to <15%), and high (≥15%) CD rates. Average sperm numbers were lowest in the high CD group (2.08 × 109/mL). Membrane integrity and mitochondrial activity did not differ between the groups. Breakpoint analysis indicated a shift towards lower litter sizes when the CD rate exceeded 11%. Group comparisons revealed no difference in litter size (p = 0.205), together with a slightly higher farrowing rate in the high CD group (p < 0.001), which coincided with higher resistance against temperature stress in the stored semen samples (p < 0.001) and a higher sperm motility (p < 0.001). In conclusion, an increased prevalence of CD in boar semen is compensable by high tolerance against temperature stress, whereas sperm numbers per dose are less relevant.

Currently, 52% of all raptor species demonstrate a decreasing population tendency, and the American harpy eagle (Harpia harpyja) has been categorized as \"near threatened\" by the IUCN. Habitat loss, persecution, and subsequent reduction of genetic diversity are regarded as major threats to the world\'s strongest eagle. Captive breeding and reintroduction into protected habitats are approaches of species conservation projects, but captive propagation is difficult due to low ex-situ numbers and scarce successful breeding pairs. The aim of the present study was to collect, analyze, and store semen from harpy eagles and to use aliquots for artificial insemination to increase the number of offspring and to include more individuals into the ex-situ gene pool. First, semen collection and semen availability were assessed in four males during the course of 1 year in European zoos. Second, these experiences were transferred to ex-situ breeding programs in Brazilian zoos to attempt semen collection in 13 male eagles. Semen collection was successful in 51.7% of the attempts and in 8/13 males (individual success rates 20-100%) using electro-stimulation. Most commonly, whey-like to milky, whitish semen samples were collected, regularly containing urate impurities (67.7%). The median semen volume was 106 μl and the median sperm concentration 5,000 sperm/μl (750-22,500 sperm/μl). Mean values for pH were 6.7, for sperm motility 27.7 ± 22.6%, for progressive motility 2.9 ± 5.6%, and for sperm viability 46.6 ± 16.3%. Using semen extenders, a sperm motility of 8% was maintained for 27 h in the refrigerator. Artificial insemination was performed in one female, but the success of fertilization could not be assessed due to egg destruction. In this study, methods for assisted reproduction were refined for use in harpy eagles, and the first semen samples were evaluated as a start to establish species-specific orientation values.

This case study describes the effects of a contamination of boar bedding material with reprotoxic compounds in an AI centre in southern Germany. The origin of the investigations was an extreme decline in the production output of the boars. In July 2021, more than 54% of boars were not in production and over 45% of ejaculates had insufficient sperm quality and quantity, which is a significant drop in comparison with the other months. This drop was accompanied by oligozoospermia (azoospermia), asthenozoospermia and teratozoospermia. Through intensive troubleshooting, the changes could be attributed to fenpropimorph, an ergosterol biosynthesis-inhibiting fungicide with reprotoxic potential, which was found in the sawdust used as bedding as well as in liver samples of affected animals, reaching a concentration (mean ± SD) between 0.20 ± 0.36 mg/kg and 0.019 ± 0.001 mg/kg respectively. Furthermore, autopsy findings revealed hyperaemia of the testis, histologically focal degeneration of the germinal epithelium and signs of reduced spermatogenesis and spermiogenesis.

Is there a relation between the characteristics of potential sperm donors and the acceptance rate of these potential donors?
A relatively higher acceptance rate was observed for potential sperm donors who were aged ≤ 35 years, were married, had children, and who had received higher education, and acceptance rates were also higher during spring and winter than summer and autumn.
Recruiting donors to a sperm bank program is difficult and slow owing to the high rates of rejection and dropout.
A total of 24040 potential sperm donors were screened by the Henan Human Sperm Bank from 2006 to 2019.
Potential sperm donors were recruited using the following baseline requirement: height of 168 cm or taller; age 22-45 years; currently attending or had graduated from high school or above. Men who met the criteria for age, height, and education level were invited for semen quality screening. The acceptable criteria for semen samples included liquefaction time < 60min, volume ≥ 2mL, sperm concentration ≥ 60 × 106/mL, progressive motility ≥ 60%, post-thaw motility ≥ 40%, pre-freezing total motile sperm per vial > 30 × 106/mL, post-thaw total motile sperm per vial > 12 × 106/mL, and freeze-thaw survival rate ≥ 60%. Any potential sperm donors meeting the minimum criteria for acceptable semen quality on two consecutive semen samples were scheduled for clinical assessment, physical examination, and laboratory tests. The reasons for sperm donor rejection were analyzed. The characteristics of accepted and rejected donors were compared using the chi-square test, and multivariate logistic regression analyses were conducted to identify factors associated with the acceptance rate of potential sperm donors and the positive rate of sexually transmitted diseases (STDs).
Only 23.38% (5620/24040) of potential sperm donors were accepted. The top four reasons for rejection were suboptimal semen quality (90.27%), STDs (6.26%), dropped out (2.65%), and chromosomal abnormalities (0.35%). The most common reason for the rejection of donors with an STD was a positive test for mycoplasmas (49.05%), followed by hepatitis B virus (27.56%), Chlamydia trachomatis (4.68%), and Escherichia coli (3.03%). n this study, the acceptance rate for men aged ≤ 35 years was significantly higher than that for men aged >35 years (P < 0.05). The acceptance rates were also significantly higher for men with a higher education than for men with lower education, married men than unmarried men, and men with children than men without children (P < 0.05). Moreover, acceptance rates were significantly higher during spring and winter than during summer (P <0.05) but were not significantly higher during autumn than during summer (P >0.05).
This study was not performed to analyze the effect of lifestyle habits, such as alcohol consumption and cigarette smoking, on the acceptance rate of potential sperm donors.
Only a small proportion of potential sperm donors were accepted in this anonymous sperm donor program. New strategies for sperm donor recruitment may be required to improve the acceptance rate. In the future, we may have to target potential sperm donors who are aged ≤ 35 years and who received higher education in order to improve the acceptance rate.
This work was supported by the Joint Construction Project of Henan Medical Science and Technology Research Plan under grant number LHGJ20190389. The authors report no conflict of interest.
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In sheep, cervical artificial insemination (AI) involves depositing semen at the cervical opening, as it is not possible to traverse the cervix due to its complex anatomy. However, internationally this method yields low pregnancy rates when frozen-thawed semen is used. An exception to this is in Norway, in which vaginal deposition of frozen-thawed semen to a natural estrus yields pregnancy rates around 70%. As the cervix and its secretions are the principal factors influencing sperm transport to the site of fertilization the aim of this study was to characterise the differences in the cervical anatomy as well as the cervicovaginal mucus properties of six European ewe breeds across three countries known to have differences in pregnancy rates following cervical AI with frozen-thawed semen. These were Suffolk and Belclare in Ireland, Fur and Norwegian White Sheep (NWS) in Norway and Ile de France and Romanov in France (n = 28-30 ewes/breed). Cervicovaginal mucus was collected at the follicular and luteal phases of both a synchronized and natural cycle and assessed for mucus weight, viscosity and colour. The anatomical characteristics of the cervix (length of the cervix, number of cervical rings and the appearance of the external os) were assessed post-mortem. There was a type of the cycle by ewe breed interaction represented by no differences in mucus production between ewe breeds at the natural cycle for both the follicular and luteal phases of the cycle. However, there were differences between ewe breeds at the synchronized cycle (P < 0.05). Belclare had the lowest mucus production at the follicular phase while NWS had the lowest amount of mucus at the luteal phase of the synchronized cycle. Overall, across all ewe breeds, mucus production was higher at the follicular than at the luteal phase (P < 0.05). Despite reports of Suffolk and NWS having the most divergent pregnancy rates following cervical AI with frozen-thawed semen, both breeds had the lowest overall mucus viscosity at the follicular phase of both types of cycle with no differences between both ewe breeds (P > 0.05). The length of the cervix, number of cervical rings and the external os type were affected by ewe breed (P < 0.05). Suffolk ewes had longer cervices but lower number of cervical rings than NWS and Fur ewes (both with higher pregnancy rates). In conclusion, while mucus production and mucus viscosity was affected by breed, these changes are not consistent with the known differences between ewe breeds in their pregnancy rates following cervical AI with frozen-thawed semen.

The successful development and application of an assisted breeding program in any animal relies primarily on a thorough understanding of the fundamental reproductive biology (anatomy, physiology and behaviour) of the species in question. Surely, the ultimate goal and greatest hallmark of such a program is the efficacious establishment of a series of reliable techniques that facilitate the reproductive and genetic management of fragmented populations, both in captivity and in the wild. Such an achievement is all that more challenging when knowledge of the reproductive biology of that species is essentially rudimentary and without adequate models to compare to. Using the koala (Phascolarctos cinereus) as a case study, this chapter provides insights into the development of a concept that began as small undergraduate student project but that subsequently evolved into the first-ever successful artificial insemination of a marsupial. Apart from this historical perspective, we shall also provide a brief review of the current reproductive biology of the koala, discuss technical elements of current assisted breeding technology of this species, its application to the closely related wombat, and the potential role it might play in helping to conserve wild koala populations in the form of a live koala genome bank. There is little doubt that the unique reproductive biology and tractability of the koala has been a benefit rather than a hindrance to the success of artificial breeding in this species.

Conception rate with the use of sexed semen is lower than that with the use of conventional semen, posing a major problem in the dairy industry. The aim of this study was to understand the risk factors that affect the conception rate after artificial insemination (AI) with conventional and sexed semen using field data. The records of the first insemination in Holstein heifers with conventional (n = 41,857) and sexed semen (n = 45,465) in Hokkaido, Japan were analyzed. The mean conception rate after AI from 2012 to 2016 was 56.9% with conventional semen and 47.3% with sexed semen. A multivariable logistic regression model including the effects of year, heifer age, time of the year, semen type, service sire, and their interactions was used to evaluate the interaction effect of heifer age and time of the year by semen type on the conception rate. In the analysis using heifer age, we found that heifers inseminated with sexed semen were approximately 21 days younger than those inseminated with conventional semen. Interestingly, in early, warmer months (Jun, Jul, and Aug), the conception rate after AI with sexed semen significantly decreased compared with that after AI with conventional semen (P < 0.01). Our results showed that more careful implementation of AI is required for a stable conception using sexed semen, particularly during warmer months.