Sex cells Almeling, Rene
2011., 20110821, 2011, 2011-09-20, 20110101
eBook
Unimaginable until the twentieth century, the clinical practice of transferring eggs and sperm from body to body is now the basis of a bustling market. In Sex Cells, Rene Almeling provides an inside ...look at how egg agencies and sperm banks do business. Although both men and women are usually drawn to donation for financial reasons, Almeling finds that clinics encourage sperm donors to think of the payments as remuneration for an easy "job." Women receive more money but are urged to regard egg donation in feminine terms, as the ultimate "gift" from one woman to another. Sex Cells shows how the gendered framing of paid donation, as either a job or a gift, not only influences the structure of the market, but also profoundly affects the individuals whose genetic material is being purchased.
Good quality Wahlberg, Ayo
2018., 20180403, 2018, 2018-09-20
eBook
From its crude and uneasy beginnings thirty years ago, Chinese sperm banking has become a routine part of China’s pervasive and restrictive reproductive complex. Today, there are sperm banks in each ...of China’s twenty-two provinces, the biggest of which screen some three thousand to four thousand potential donors each year. Given the estimated one to two million azoospermic men--those who are unable to produce their own sperm--the demand remains insatiable. China’s twenty-two sperm banks cannot keep up, spurring sperm bank directors to publicly lament chronic shortages and even warn of a national ‘sperm crisis’ (jingzi weiji). Good Quality explores the issues behind the crisis, including declining sperm quality in the country due to environmental pollution, as well as a chronic national shortage of donors. In doing so, Wahlberg outlines the specific style of Chinese sperm banking that has emerged, shaped by the particular cultural, juridical, economic and social configurations that make up China’s restrictive reproductive complex. Good Quality shows how this high-throughput style shapes the ways in which men experience donation and how sperm is made available to couples who can afford it.
Interest in the study of kinship, a key area of anthropological enquiry, has recently reemerged. Dubbed 'the new kinship', this interest was stimulated by the 'new genetics' and revived interest in ...kinship and family patterns. This volume investigates the impact of biotechnology on contemporary understandings of kinship, of family and 'belonging' in a variety of European settings and reveals similarities and differences in how kinship is conceived. What constitutes kinship for different publics? How significant are biogenetic links? What does family resemblance tell us? Why is genetically modified food an issue? Are 'genes' and 'blood' interchangeable? It has been argued that the recent prominence of genetic science and genetic technologies has resulted in a 'geneticization' of social life; the ethnographic examples presented here do show shifts occurring in notions of 'nature' and of what is 'natural'. But, they also illustrate the complexity of contemporary kinship thinking in Europe and the continued interconnectedness of biological and sociological understandings of relatedness and the relationship between nature and nurture.
Over the years, reproductive efficiency in the swine industry has focused on reducing the sperm cell number required per sow. Recent advances have included the identification of subfertile boars, new ...studies in extended semen quality control, new catheters and cannulas for intrauterine artificial insemination (AI), and fixed‐time AI under commercial use. Therefore, it is essential to link field demands with scientific studies. In this review, we intend to discuss the current status of porcine AI, pointing out challenges and opportunities to improve reproductive efficiency.
Our objective was to compare the AI submission rate and pregnancies per artificial insemination (P/AI) at first service of lactating Holstein cows submitted to a Double-Ovsynch protocol and timed ...artificial insemination (TAI) versus artificial insemination (AI) to a detected estrus after synchronization of estrus at a similar day in milk range. Lactating Holstein cows were randomly assigned to receive their first TAI after a Double-Ovsynch protocol (DO; n = 294) or to receive their first AI after a synchronized estrus (EST; n = 284). Pregnancy status was determined 33 ± 3 d after insemination and was reconfirmed 63 ± 3 d after insemination. Data were analyzed by ANOVA and logistic regression using the MIXED and GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC). By design, days in milk at first insemination did not differ between treatments (76.9 ± 0.2 vs. 76.7 ± 0.3 for DO vs. EST cows, respectively), but more DO cows were inseminated within 7 d after the end of the voluntary waiting period than EST cows (100.0 vs. 77.5%). Overall, DO cows had more P/AI than EST cows at both 33 d (49.0 vs. 38.6%) and 63 d (44.6 vs. 36.4%) after insemination, but pregnancy loss from 33 to 63 d after insemination did not differ between treatments. Primiparous cows had more P/AI than multiparous cows 33 and 63 d after insemination, but the treatment by parity interaction was not significant. Synchronization rate to the hormonal protocols was 85.3%, which did not differ between treatments; however, synchronized DO cows had more P/AI 33 d after insemination than synchronized EST cows (54.7 vs. 44.5%). In summary, submission of lactating Holstein cows to a Double-Ovsynch protocol and TAI for first insemination increased the percentage of cows inseminated within 7 d after the end of the voluntary waiting period and increased P/AI at 33 and 63 d after first insemination resulting in 64 and 58% more pregnant cows, respectively, than submission of cows for first AI after detection of estrus at a similar day in milk range. We conclude that, because the proportion of synchronized cows did not differ between treatments, DO cows had more P/AI than EST cows because of an intrinsic increase in fertility after submission to a fertility program.
Two experiments were conducted to evaluate an accelerometer system (Heatime; SCR Engineers Ltd., Netanya, Israel) to manage reproduction in lactating dairy cows. In experiment 1, lactating Holstein ...cows (n=112) were fitted with an accelerometer system and were treated with GnRH followed 7d later by PGF2α to synchronize estrus. A total of 89 cows that had a follicle >10mm in diameter and a functional corpus luteum at the PGF2α injection that regressed by 48h after induction of luteolysis were included in the analysis. Overall, 71% of cows were detected in estrus by the accelerometer system and 95% of cows showing estrus ovulated within 7d after induction of luteolysis. Of the cows not detected in estrus by the accelerometer system, 35% ovulated within 7d after induction of luteolysis. Duration of estrus activity (mean ± SD) was 16.1±4.7h and was neither affected by parity nor milk production. Intervals (means ± SD) from induction of luteolysis, onset of activity, peak raw activity, and peak weighted activity to ovulation was 82.2±9.5, 28.7±8.1, 20.4±7.8, and 16.4±7.4h, respectively, and the interval from AI to ovulation was 7.9±8.7h, but ranged from −12 to 26h. In experiment 2, cows were assigned randomly to receive an intramuscular injection of GnRH at artificial insemination (AI) after detection of estrus by the accelerometer system or receive no treatment (control). Nine hundred seventy-nine AI services from 461 cows were analyzed. Treatment with GnRH at AI did not affect fertility at 35 or 65d after AI, and no interaction was detected between treatment and season or treatment and AI number. Overall, two-thirds of the cows that were considered properly synchronized were inseminated based on the accelerometer system and ovulated after AI. The remaining cows either were not inseminated because they were not detected in estrus or would not have had a chance to conceive to AI because they failed to ovulate after estrus. Furthermore, mean time of AI in relation to ovulation determined by the accelerometer system was acceptable for most of the cows that displayed estrus; however, variability in the duration of estrus and timing of AI in relation to ovulation could lead to poor fertility in some cows. For lactating dairy cows detected in estrus by the accelerometer system, treatment with GnRH at the time of AI without reference to the onset of estrus did not increase fertility.
Background: Male livestock rendered sterile through vasectomy or epididymectomy, but still hormonally and behaviourally sexually active, have many uses. In small ruminants they can be used to advance ...the breeding season and puberty, synchronise and detect oestrus and improve conception rates to artificial insemination. In pigs, they can be used to hasten first oestrus in gilts and detect oestrus in sows. In cattle, they can be used to aid heat detection for artificial insemination.
Aim of the article: This article outlines the surgical techniques used to produce such ‘teaser’ animals and discusses how they can be best used, as well as the alternatives to their use.
The objective of this observational study was to evaluate the association between increased physical activity at first artificial insemination (AI) and subsequent pregnancy per AI (P/AI) in lactating ...Holstein cows following spontaneous estrus or a timed AI (TAI) protocol. We also wanted to identify factors associated with the intensity of activity increase (PA) captured by automated activity monitors (AAM) and fertility. Two experiments were conducted, in which cows either were inseminated based on the alert of the AAM system (AAM cows) or received TAI following a 7-d Ovsynch protocol (TAI cows) if not inseminated within a farm-specific period after calving. Experiment 1 included 2,698 AI services from AAM cows and 1,042 AI services from TAI cows equipped with the Smarttag Neck (Nedap Livestock Management) from a dairy farm in Slovakia (farm 1). In the second experiment, 6,517 AI services from AAM cows and 1,226 AI services from TAI cows fitted with Heatime (Heatime Pro; SCR Engineers Ltd.) from 8 dairy farms in Germany (farms 2–9) were included. Pregnancy diagnosis was performed on a weekly basis by transrectal ultrasound (farms 1, 3, 7, 8) or by transrectal palpation (farms 2, 4–6, 9). Estrous intensity was represented by the peak value of the change in activity. In experiment 1, PA was categorized into low (x-factor 0–20) and high (x-factor 21–100) PA, and in experiment 2 into low (activity change = 35–89) and high (activity change = 90–100) PA. In TAI cows from both experiments, PA was additionally categorized into cows with no AAM alert. Data were analyzed separately for AAM and TAI cows using multinomial logistic regression models for PA in TAI cows and logistic regression models for PA in AAM cows and P/AI in both groups. In experiment 1, P/AI of AAM cows was greater for AI services performed with conventional frozen semen (57.6%) compared with sexed semen (47.2%), whereas type of semen only tended to be associated with P/AI in TAI cows (54.4% conventional frozen semen vs. 48.9% sexed semen). In experiment 2, P/AI was greater for fresh semen (AAM cows: 44.4% vs. TAI cows: 44.2%) compared with conventional frozen semen (AAM cows: 37.6% vs. TAI cows: 34.6%). In both experiments, pregnancy outcomes were associated with PA. In experiment 1, AAM cows with high PA (55.1%) had greater P/AI than cows with low PA (49.8%). Within TAI cows, cows with no alert (38.8%) had reduced P/AI compared with cows with low (54.2%) or high PA (61.8%). In experiment 2, AAM cows with high PA (45.8%) had greater P/AI compared with cows with low PA (36.4%). Timed AI cows with no alert (27.4%) had decreased P/AI compared with cows with low (41.1%) or high (50.8%) PA. The greatest risk factors for high PA were parity (experiment 1) and season of AI (except for TAI cows from experiment 1). We conclude that high PA at the time of AI is associated with greater odds of pregnancy for both AAM and TAI cows. In both experiments, about 2 thirds of AAM cows (experiment 1: 69.9% and experiment 2: 70.7%) reached high PA, whereas only approximately one-third or less of TAI cows (experiment 1: 37.3% and experiment 2: 23.6%) showed high PA. Although we observed similar results using 2 different AAM systems for the most part, risk factors for high PA might differ between farms and insemination type (i.e., AAM vs. TAI).
Management of the ovine oestrous cycle is mainly based on the use of exogenous hormones to mimic or enhance (progesterone and its analogues) or manipulate (prostaglandin F2α and its analogues) the ...activity of the corpus luteum, combined with the application of other hormones mimicking the pituitary secretion of gonadotrophins (e.g. equine chorionic gonadotrophin). These protocols have been applied without major change for decades but, now, there are two reasons to reconsider them: (1) our greatly improved knowledge of the dynamics of ovarian physiology, following the application of transrectal ultrasonography, indicates that modification of the protocols may improve fertility yields and (2) increasing concerns about animal health and welfare, food safety and the environmental impact of the treatments, as evidenced by public opinion and therefore market forces. Here, we offer an overview of these issues, introduce an updated protocol and suggest ways for future improvements to the protocols.
A number of methods are currently used to predict the optimal date of insemination of the breeding bitch, particularly with the use of frozen–thawed canine semen which has a far shorter lifespan than ...fresh semen. Aside from confirming cytological oestrus, vaginal cytology is of no assistance in predicting the most fertile day(s) in a bitch; however, a neglected avenue of research suggests that vaginal cytology may be of great importance in confirming the days of optimal fertility retrospectively. Similarly, vaginoscopy provides clues as to the stage of a bitch's cycle but is inadequate as a sole determinant of her most fertile days. Nevertheless, vaginoscopy is useful to identify very late oestrus and the onset of dioestrus, as well as Stage I of labour (cervical dilatation). Due to variations in the rate at which circulating progesterone concentrations rise in individual bitches, the reliability of circulating progesterone concentrations for determining the optimal day(s) of insemination with frozen–thawed semen decreases as values rise. Moreover, progesterone assay results can vary widely due to extrinsic factors such as the time of blood sampling, sample storage conditions and the assay employed. Finally, this review investigates evidence surrounding various insemination routes and suggests that well‐performed vaginal insemination, even with frozen–thawed semen, may be an acceptable approach for cases where transcervical insemination is impractical.
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