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At least 19 recordsLinked to original sources
PubMed2007

Spectacular reproduction: Ron's Angels and mechanical reproduction in the age of ART (assisted reproductive technology).

Ron Harris captured the popular imagination in October 1999 with a website where he auctioned off the ova of fashion models to the highest bidder. This article treats the controversy surrounding Harris' site within a dual frame of critical theory's approach to reproduction and a folkloristic approach to discourse. The website fuses traditional narrative motifs and structures with the logic of advertising, seventies television, family-values rhetoric, and the fertility industry. I argue that the great attraction of ronsangels.com is that it put into relief the intervention of mechanical reproduction in human fertility together with the state of genetics at the turn of the 21st century. The result is not only a disconcerting aestheticization and commodification of biological reproduction, but also the biological reproduction of a particular aesthetic and moral code--a generation of reality by model.

Advertising↗
PubMed2005

Correlation of cell-mediated immunity against porcine reproductive and respiratory syndrome virus with protection against reproductive failure in sows during outbreaks of porcine reproductive and respiratory syndrome in commercial herds.

OBJECTIVE: To determine whether cell-mediated immunity against porcine reproductive and respiratory syndrome (PRRS) virus is correlated with protection against reproductive failure in sows during clinical outbreaks of PRRS in commercial herds. DESIGN: Outbreak investigation in 4 swine breeding herds. ANIMALS: 97 sows. PROCEDURES: On each farm, blood samples were collected from sows with clinical signs (abortion or increased fetal death; case sows) and from clinically normal sows (control sows). The intensity of the cell-mediated immune (CMI) response was determined by use of an interferon-gamma enzyme-linked immunospot (ELISPOT) assay. Multiple logistic regression analyses and t tests were used to compare ELISPOT assay values between case and control sows. Multiple linear regression was used to investigate associations between cell-mediated immunity and the magnitude of clinical signs. RESULTS: In 2 farms, case sows had lower ELISPOT assay values than control sows. A negative association between the intensity of the CMI response and the number of pigs born dead per litter was detected on 1 farm. In 1 farm, no association was detected between the intensity of the CMI response and protection against reproductive failure. CONCLUSIONS AND CLINICAL RELEVANCE: Evidence that a strong CMI response was correlated with protection against clinical PRRS was detected in 3 of 4 farms. However, farms and sows within farms varied considerably in their immune responsiveness and in the degree to which they were protected clinically. Increasing cell-mediated immunity within infected herds has the potential to decrease clinical reproductive disease, but only if the sources of intra- and interfarm variation in the intensity of cell-mediated immunity to PRRS virus can be identified.

Abortion, Veterinary↗
PubMed2000

Assisted reproductive technology in the United States: 1997 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of assisted reproductive technology (ART) initiated in the United States in 1997. DESIGN: Data were collected electronically by using Society for Assisted Reproductive Technology Clinical Outcome Reporting System software and were submitted to the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. PARTICIPANT(S): 335 programs submitted data on procedures performed in 1997. Data were collated after November 1998 so that the outcome of all pregnancies established would be known. MAIN OUTCOME MEASURE(S): Incidence of clinical pregnancy, ectopic pregnancy, abortion, stillbirth, delivery, and structural and functional abnormalities. RESULT(S): Programs reported initiating 73,069 cycles of ART treatment. Of these, 51,344 cycles involved IVF (with and without micromanipulation), with a delivery rate per retrieval of 27.9%; 1,943 were cycles of GIFT, with a delivery rate per retrieval of 30.0%; and 1,104 were cycles of zygote intrafallopian transfer, with a delivery rate per retrieval of 28.0%. The following additional ART procedures were also initiated: 4,616 donor oocyte cycles, with a delivery rate per transfer of 40.0%; 10,181 frozen embryo transfer procedures, with a delivery rate per transfer of 18.8%; 1,584 frozen embryo transfers using donated oocytes, with a delivery rate per transfer of 22.2%; and 600 cycles using a host uterus, with a delivery rate per transfer of 34.6%. Furthermore, 1,173 cycles were reported as combinations or more than one treatment type, 40 cycles as research, 258 as embryo banking, and 226 as other (unclassified) cycle types. As a result of all procedures, 17,311 deliveries resulting in 25,059 babies were reported. CONCLUSION(S): In 1997, more programs reported ART treatment and the number of reported cycles increased significantly (10.9%) compared with 1996. In comparable cycle types, the overall success rate (deliveries per retrieval) increased by 1.8%, which represents an increase of 6.9% compared with the success rate for 1996.

Abortion, Spontaneous↗
PubMed1996

Assisted reproductive technology in the United States and Canada: 1994 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of assisted reproductive technology (ART) initiated in the United States in 1994. DESIGN: Data were collected on the Society for Assisted Reproductive Technology (SART) Database program and submitted to KMPG Peat Marwick, who served as the 1994 collection center for the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. PARTICIPANT(S): Two hundred forty-nine programs submitted data on procedures performed in 1994. Data were collected after October 1995 so that outcome of all pregnancies established would be known. MAIN OUTCOME MEASURE(S): The outcomes measured included clinical pregnancy, ectopic pregnancy, abortion, stillbirth, delivery, and congenital abnormality. RESULT(S): Programs reported initiations of 39,390 cycles of ART treatment, excluding frozen embryo and donor oocyte cycles. Of these, 33,700 cycles initiated were IVF (standard, with micromanipulation, and for host uterus transfer) with 20.7% deliveries per retrieval; 4,214 were cycles of GIFT with 28.4% deliveries per retrieval; 926 were cycles of zygote intrafallopian transfer with 29.1% deliveries per retrieval; and 550 were combination cycles, combining IVF and one of the tubal transfer techniques, resulting in 29.7% deliveries per retrieval. In addition to these cycles initiated in 1994, 7,046 frozen ET procedures were reported, either as separate procedures or in combination with another ART procedure with 15.4% deliveries per procedure, and 3,119 donor oocyte cycles were initiated with an overall success of 46.8% deliveries per retrieval. As a result of all procedures, a total of 9,573 deliveries were reported. CONCLUSION(S): In 1994, there were fewer programs reporting a similar number of treatment cycles of ART as in 1993. Overall average success rates (deliveries per procedures) exhibited only a small increase compared with previously reported summaries.

Adult↗
PubMed1998

Assisted reproductive technology in the United States and Canada: 1995 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of assisted reproductive technology (ART) initiated in the United States and Canada in 1995. DESIGN: Data were collected in the Society for Assisted Reproductive Technology database program and cycle reporting forms and were submitted to the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. PARTICIPANT(S): Two hundred eighty-one programs submitted data on procedures performed in 1995. Data were collected after November 1996 so that outcome of all pregnancies established would be known. MAIN OUTCOME MEASURE(S): Procedural outcomes measured included clinical pregnancy, ectopic pregnancy, abortion, stillbirth, delivery, and congenital abnormality. RESULT(S): Programs reported initiating 59,142 cycles of ART treatment, including frozen embryo and donor oocyte cycles. Of these, 41,087 cycles initiated were IVF (with and without micromanipulation) with 22.5% deliveries per retrieval; 3,741 were cycles of gamete intrafallopian transfer with 27.0% deliveries per retrieval; 1,078 were cycles of zygote intrafallopian transfer with 27.9% deliveries per retrieval. In addition to these cycles initiated in 1995, 8,453 frozen embryo thaw procedures were reported, either as separate procedures or in combination with other ART procedures with 15.2% deliveries per transfer, 3,555 donor oocyte cycles were initiated with an overall success of 36.0% deliveries per transfer, 1,028 cryopreserved embryo thaw procedures from donated oocyte procedures with an overall success of 16.8% deliveries per transfer, and 200 ART treatment cycles in which a host uterus was used were initiated with an overall success of 34.9% deliveries per ET. As a result of all procedures, a total of 11,631 deliveries were reported, resulting in 16,520 neonates. CONCLUSION(S): In 1995, there were more programs reporting ART treatment and a significant (19.3%) increase in reported cycles. In comparable cycle types, overall average success rates (deliveries per transfer) exhibited a 0.6% increase or a 2.5% increase over the rates in the 1994 reported summaries.

Adult↗
PubMed1999

Assisted reproductive technology in the United States: 1996 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of assisted reproductive technology (ART) initiated in the United States in 1996. DESIGN: Data were collected electronically using the Society for Assisted Reproductive Technology Clinical Outcome Reporting System software and submitted to the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. PARTICIPANT(S): Three hundred programs submitted data on procedures performed in 1996. Data were collected after November 1997 so that the outcome of all pregnancies established would be known. MAIN OUTCOME MEASURE(S): Procedural outcomes measured included clinical pregnancy, ectopic pregnancy, abortion, stillbirth, delivery, and congenital abnormality. RESULT(S): Programs reported initiating 65,863 cycles of ART treatment, including frozen embryo and donor oocyte cycles. Of these. 44,647 cycles initiated were in vitro fertilization (IVF) (with and without micromanipulation) with 26.0% deliveries per retrieval; 2,879 were cycles of gamete intrafallopian transfer (GIFT) with 29.0% deliveries per retrieval; 1,200 were cycles of zygote intrafallopian transfer (ZIFT) with 30.9% deliveries per retrieval. In addition to these cycles initiated in 1996, 9,610 frozen embryo transfer procedures were initiated with 16.8% deliveries per transfer, 3,768 donor oocyte cycles were initiated with an overall success of 39.1% deliveries per transfer, 1,096 cryopreserved embryo transfers from donated oocytes procedures with an overall success of 20.8% deliveries per transfer, and 688 ART treatment cycles using a host uterus were initiated with an overall success of 31.3% deliveries per embryo transfer. Also, 1,341 cycles were reported as combinations of more than one treatment type, 19 cycles as research, 311 as embryo banking, and 304 as other (unclassified) cycle types. As a result of all procedures, a total of 14,702 deliveries were reported resulting in 21,196 neonates. CONCLUSION(S): In 1996, there were more programs reporting ART treatment and a significant (11.3%) increase in reported cycles. In comparable cycle types, overall average success rates (deliveries per retrieval) exhibited an actual increase of 3.5% (this is an increase of 15.8% when compared to the success rate for 1995).

Female↗
PubMed2006

Monitoring reproductive health in Europe: what are the best indicators of reproductive health? A need for evidence-based quality indicators of reproductive health care.

Monitoring reproductive health by the Reprostat indicators in Europe will facilitate the transparency of reproductive health as well as comparisons over time and between countries. However, for the monitoring and improvement of reproductive health care, we suggest the systematic development of evidence-based quality indicators, especially process and structure indicators.

Europe↗
PubMed1995

Assisted reproductive technology in the United States and Canada: 1993 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of assisted reproductive technology (ART) initiated in the United States in 1993. DESIGN: Data were collected on an annual summary form and submitted to the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. PARTICIPANTS: Two hundred sixty-seven programs submitted data on procedures performed in 1993. Data were collected in October 1994 so that outcome of all pregnancies established would be known. MAIN OUTCOME MEASURES: The outcomes measured included clinical pregnancy, ectopic pregnancy, abortion, stillbirth, delivery, and congenital abnormality. RESULTS: Programs reported initiations of 41,209 cycles of ART treatment, excluding frozen embryo and donor oocyte cycles. Of these, 33,543 cycles initiated were IVF (standard, with micromanipulation, and for host uterus transfer) with 18.3% deliveries per retrieval; 4,992 were cycles of GIFT with 28.1% deliveries per retrieval; 1,792 were cycles of ZIFT with 24.4% deliveries per retrieval; and 882 were combination cycles, combining IVF and one of the tubal transfer techniques, resulting in 27.8% deliveries per retrieval. In addition to these cycles initiated in 1993, 6,869 frozen ET procedures were reported, either as separate procedures or in combination with another ART procedure with 13.3% deliveries per procedure, and 2,766 donor oocyte cycles were initiated with an overall success of 30.2% deliveries per retrieval. As a result of all procedures, a total of 8,741 deliveries were reported. CONCLUSIONS: In 1993, there were more programs offering more treatment cycles of ART. Overall average success rates (deliveries per procedures) exhibited only a small increase compared with previously reported summaries.

Adult↗
PubMed2002

Assisted reproductive technology in the United States: 1998 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of ART initiated in the United States in 1998. DESIGN: Data were collected electronically by using the SART Clinical Outcome Reporting System software and submitted to the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. PARTICIPANT(S): Three hundred and sixty programs submitted data on procedures performed in 1998. Data were collated after November 1999 so that the outcome of all pregnancies established would be known. MAIN OUTCOME MEASURE(S): Incidence of clinical pregnancy, ectopic pregnancy, abortion, stillbirth, and delivery. RESULTS: Programs reported initiating 81,899 cycles of ART treatment. Of these, 58,937 cycles involved IVF (with and without micromanipulation), with a delivery rate per retrieval of 29.1%; 1,293 were cycles of gamete intrafallopian transfer, with a delivery rate per retrieval of 27.4%; 1,054 were cycles of zygote intrafallopian transfer with a delivery rate per retrieval of 29.6%. The following additional ART procedures were also initiated: 5,273 fresh donor oocyte cycles, with a delivery rate per transfer of 41.2%; 11,228 frozen embryo transfer procedures, with a delivery rate per transfer of 19.3%; 1,913 frozen embryo transfers using donated oocytes or embryos, with a delivery rate per transfer of 23.5%, and 809 cycles using a host uterus, with a delivery rate per transfer of 31.6%. In addition, 969 cycles were reported as combinations or more than one treatment type, 25 cycles as research, and 398 as embryo banking. As a result of all procedures, 20,241 deliveries were reported, resulting in 29,128 neonates. CONCLUSIONS: In 1998, there were more programs reporting ART treatment and a significant (12.1%) increase in reported cycles compared with 1997. In comparable cycle types, the actual increase in overall success rate (deliveries per retrieval) was 1.4%, which represents an increase of 4.7% compared with the success rate in 1997.

Adult↗
PubMed2002

Assisted reproductive technology in the United States: 1999 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of ART initiated in the United States in 1999. DESIGN: Data were collected electronically by using the SART Clinical Outcome Reporting System software and submitted to the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. PARTICIPANT(S): Three hundred sixty programs submitted data on procedures performed in 1999. Data were collated after November 2000 so that the outcome of all pregnancies established would be known. MAIN OUTCOME MEASURE(S): Incidence of clinical pregnancy, ectopic pregnancy, abortion, stillbirth, and delivery. RESULT(S): Programs reported initiating 88,077 cycles of ART treatment. Of these, 63,639 cycles involved IVF (with and without micromanipulation), with a delivery rate per retrieval of 29.4%; 838 were cycles of gamete intrafallopian transfer, with a delivery rate per retrieval of 27.9%; 945 were cycles of zygote intrafallopian transfer, with a delivery rate per retrieval of 29.8%. The following additional ART procedures were also initiated: 6,509 fresh donor oocyte cycles, with a delivery rate per transfer of 41.8%; 12,005 frozen embryo transfer procedures, with a delivery rate per transfer of 18.6%; 2,488 frozen embryo transfers using donated oocytes or embryos, with a delivery rate per transfer of 23.6%, and 821 cycles using a host uterus, with a delivery rate per transfer of 33.6%. In addition, 398 cycles were reported as combinations of more than one treatment type, 18 cycles as research, and 416 as embryo banking. As a result of all procedures, 21,904 deliveries were reported, resulting in 30,967 neonates. CONCLUSION(S): In 1999, more programs reported ART treatment and reported cycles increased significantly (7.5%) compared to 1998. In comparable cycle types, the overall success rate (deliveries per retrieval) increased by 0.4%, which represents an increase of 1.2% compared to the success rate for 1998.

Adult↗
PubMed1978

[Reproductive lifespan and reproductive performance in SPF C3H mice: the onset of reproductive life and production efficiency (author's transl)].

To improve the production system, the onset and the termination of reproductive life of C3Hf/HeMsNrs mice mated immediately after weaning and reared for 400 days of life, were studied. From weaning females mated with a full grown male (group A), the first litter was obtained at a mean age of 47 days, suggesting the first copulation at 26 days of age. The age of males at the first copulation was estimated to be at 44 days of age from the age giving the first litters in weanling males mated with weanling (group B) and full grown (group C) females. The sex ratio of litters delivered by young dams tended to be excess in males. The reproductive performance of dams in later life was not affected by the parturition in earlier age. The production efficiency with weaned youngs per pair during the first 200 days after mating was the highest in group A. It was found from these results that the C3H females attained their sexual maturity at 5 to 6 days after weaning, being available for breeding without any deletion in reproductive performance.

Age Factors↗
PubMed2004

Assisted reproductive technology in the United States: 2000 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry.

OBJECTIVE: To summarize the procedures and outcomes of ART initiated in the United States in 2000. DESIGN: Data were collected electronically using the SART Clinical Outcome Reporting System software and submitted to the American Society for Reproductive Medicine/ Society for Assisted Reproductive Technology Registry. PARTICIPANT(S): Three hundred eighty-three programs submitted data on procedures performed in 2000. Data were collated after November 2000 so that the outcome of all pregnancies established would be known. MAIN OUTCOME MEASURE(S): Incidence of clinical pregnancy, ectopic pregnancy, abortion, stillbirth, and delivery. RESULT(S): Programs reported initiating 99,989 cycles of ART treatment. Of these, 73,406 cycles involved fresh nondonor IVF (46.6% with intracytoplasmic sperm injection [ICSI]), with a delivery rate per retrieval of 29.9%; 549 were cycles of gamete intrafallopian transfer, with a delivery rate per retrieval of 24.7%; 763 were cycles of zygote intrafallopian transfer, with a delivery rate per retrieval of 29.9%. The following additional ART procedures were also initiated: 7,581 fresh donor oocyte cycles, with a delivery rate per transfer of 43.7%; 13,083 frozen embryo transfer procedures, with a delivery rate per transfer of 20.4%; 2,721 frozen embryo transfers using donated oocytes or embryos, with a delivery rate per transfer of 23.5%, and 1,200 cycles using a host uterus, with a delivery rate per transfer of 35.8%. In addition, 326 cycles were reported as combinations of more than one treatment type, 41 cycles as research, and 319 as embryo banking. As a result of all procedures, 25,394 deliveries were reported, resulting in 35,345 neonates, of which 35,031 were live born and 314 stillborn. CONCLUSION(S): In 2000, there were more programs reporting ART treatment and a significant (13.5%) increase in reported cycles compared to 1999. In comparable cycle types, overall success rate (deliveries per retrieval) exhibited an actual increase of 0.6%, which represents an increase of 2.2% when compared to the success rate for 1999.

Embryo Transfer↗
PubMed1989

Reproductive events, occurring in adolescence at the time of development of reproductive organs and at the time of tumour initiation, have a bearing on growth characteristics and reproductive hormone regulation in normal and tumour tissue investigated decades later--a hypothesis.

Both animal and human data indicate that reproductive events taking place early in reproductive life may have an important influence on growth characteristics and reproductive hormone regulation in both normal tissue and neoplastic tissue investigated later in life.

Adolescent↗
PubMed2002

Safety issues in assisted reproduction technology: the children of assisted reproduction confront the responsible conduct of assisted reproductive technologies.

Neurological sequelae and multiple birth defects have been observed in children conceived by IVF and ICSI. Multiple pregnancy is the most important risk factor. These health problems challenge the responsible practice of medicine. The core values of medicine and the deontology of the profession have been reviewed to define the responsible conduct of research and clinical practice. Professional associations have proposed guidelines to reduce health problems in assisted reproductive technology. Although these health problems could have been prevented, this response by the medical community is nonetheless an important step towards improving responsible medical practices that have become questionable over the years. Professional associations must find out means, not only to implement their guidelines, but also to prevent the recurrence of such episodes in the history of medicine.

Congenital Abnormalities↗
PubMed2005

Reproductive disorders of crossbred dairy cows in the central highlands of Ethiopia and their effect on reproductive performance.

The study was conducted to estimate the proportion of reproductive disorders and to determine factors affecting reproductive performance of crossbred dairy cows under four different production systems in the central highlands of Ethiopia. The principal postpartum reproductive disorders were retained fetal membranes (14.7%) and uterine infection (15.5%). Anoestrus was the major postpartum reproductive problem in the mixed crop-livestock production system (38.6%) and was significantly associated with this production system. Apart from anoestrus, the occurrence of reproductive disorders was not significantly associated with a production system. Most of the reproductive disorders occurred as a complex rather than as a single abnormality. Two or more abnormal conditions were seen in 11.4% of the cases. Each reproductive trait measured was affected adversely by reproductive disorders. Cows with reproductive disorders in each production system, lactation group and suckling and non-suckling group had longer intervals from calving to first service and to conception (p < 0.001) and required more services per conception (p < 0.001). Pregnancy rate and conception to first service were 84.7% and 51.7%, respectively, for cows without reproductive health problems; and 64.2%, and 15.1%, respectively, for cows with reproductive disorders (p < 0.001). Overall, intervals from calving to first service were shorter (p < 0.05) than in younger cows. Intervals from calving to first service and to conception were longer in suckling than in non-suckling cows (p > 0.05). Cows with a good body condition score (> 3.5) at calving had shorter calving to first service and conception intervals than cows in poor condition (p < 0.001). The results showed that reproductive abnormalities, coupled with poor body condition, are important factors that contributed to reproductive inefficiency. An appropriate reproductive health management, a reliable artificial insemination service and supplementary feeding could be the management options to reduce or alleviate some of the problems.

Anestrus↗
PubMed2006

How to improve reproductive efficacy from now in Japan? Find out the factors of late lactation to predict postpartum reproductive diseases.

Reproductive efficiency and performance in dairy cattle has been declining over the last 20 years in Japan. Recently, this has resulted in serious problems in dairy herds. There have been changes in the animals themselves and in the animal's environment, e.g. the genetic potential for milk yield has improved, the herd size of dairy farms has been expanding, the housing system of dairy cattle has been changing from tie stall to free stall, and total mixed ratio (TMR) feeding systems have become widespread. It is not clear whether the animals have adapted adequately to these environmental changes. Up till now, reproductive management has been undertaken by monitoring animal performance and/or hormonal treatments, and this has resulted in acceptable reproductive performance. However, conception and pregnancy rates have continued to decline, and the calving to calving interval has continued to extend. Consequently, the average parity and the average age at culling in dairy cattle have been declining. The most common causes of culling in dairy cattle are reproductive disorders in Japan. Therefore, in future, prevention of reproductive disorders will be required for both reproductive efficiency and animal welfare. During late pregnancy and the transition from the pregnant, non-lactating state to the non-pregnant, lactating state, dramatic changes are occurring in the dam including an increase in the fetal-placental mass and calving. Thus, the demand for energy, protein and minerals by the conceptus increases, the space within the abdominal cavity and the rumen capacity decreases due to the increased volume of the conceptus, the local immunological relationship between the fetal and maternal placenta dramatically changes, and physiological homeostasis is activated to adapt to these changes. If cattle can't maintain homeostasis before calving, the incidence of reproductive diseases will be greatly increased. We have been examining reproductive, nutritional and immunological factors to predict the occurrence of reproductive disorders as early as possible and to develop strategies to prevent them. It is unlikely that all dairy farms in Japan will be able to improve reproductive performance with general advice, due to the wide variation in feeding systems and management in Japan. Therefore, specific advice needs to be tailored to each herd, based on management systems employed within each herd. We have proposed that it is important to identify common risk factors across herds, to use these factors as an index for disease control and reproductive management and finally to demonstrate the relationship between these factors and fundamental improvement of the reproductive efficiency. We propose this approach with the aim of providing a breakthrough in improving reproductive performance in dairy cattle in Japan. The focus of this review will be that such an approach is important for improvement of the reproductive efficiency in Japanese dairy cows.

Animals↗