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Animal Reproduction Science Dec 2021Interest in the use of assisted reproductive technology in reindeer husbandry has gradually increased during the last decades. This article reviews Western and Russian... (Review)
Review
Interest in the use of assisted reproductive technology in reindeer husbandry has gradually increased during the last decades. This article reviews Western and Russian literature on reindeer semen collection, semen cryopreservation and artificial insemination. In addition, literature on the synchronisation of the stage of reindeer oestrous cycle among females, recovery of in vivo embryos, embryo transfer, the production of in vitro-produced embryos and pregnancy diagnosis is reviewed.
Topics: Animals; Cryopreservation; Embryo Transfer; Estrous Cycle; Female; Insemination, Artificial; Male; Pregnancy; Pregnancy, Animal; Reindeer; Reproductive Techniques, Assisted; Semen; Specimen Handling
PubMed: 34847527
DOI: 10.1016/j.anireprosci.2021.106890 -
Journal of Animal Science Jul 2022Ovum pickup and in vitro production (IVP) of bovine embryos are replacing traditional multiple ovulation embryo transfer (MOET) as the primary means for generating... (Review)
Review
Ovum pickup and in vitro production (IVP) of bovine embryos are replacing traditional multiple ovulation embryo transfer (MOET) as the primary means for generating transferable embryos from genetically elite sires and dams. However, inefficiencies in the IVP process limit the opportunities to produce large numbers of transferable embryos. Also, the post-transfer competency of IVP embryos is inferior to embryos produced by artificial insemination or MOET. Numerous maternal, paternal, embryonic, and culture-related factors can have adverse effects on IVP success. This review will explore the various efforts made on describing how IVP embryo development and post-transfer competency may be improved by supplementing hormones, growth factors, cytokines, steroids and other bioactive factors found in the oviduct and uterus during early pregnancy. More than 40 of these factors, collectively termed as embryokines, are reviewed here. Several embryokines contain abilities to promote embryo development, including improving embryo survivability, improving blastomere cell numbers, and altering the distribution of blastomere cell types in blastocysts. A select few embryokines also can benefit pregnancy retention after IVP embryo transfer and improve neonatal calf health and performance, although very few embryokine-supplemented embryo transfer studies have been completed. Also, supplementing several embryokines at the same time holds promise for improving IVP embryo development and competency. However, more work is needed to explore the post-transfer consequences of adding these putative embryokines for any adverse outcomes, such as large offspring syndrome and poor postnatal health, and to specify the specific embryokine combinations that will best represent the ideal conditions found in the oviduct and uterus.
Topics: Animals; Blastocyst; Cattle; Embryo Transfer; Embryo, Mammalian; Embryonic Development; Female; Fertilization in Vitro; Insemination, Artificial; Pregnancy
PubMed: 35772761
DOI: 10.1093/jas/skac091 -
Animal : An International Journal of... May 2023With the term "assisted reproduction technologies" in modern cattle farming, one could imply the collection of techniques that aim at the optimal use of bovine gametes... (Review)
Review
With the term "assisted reproduction technologies" in modern cattle farming, one could imply the collection of techniques that aim at the optimal use of bovine gametes to produce animals of high genetic value in a time- and cost-efficient manner. The accurate characterisation of sperm quality plays a critical role for the efficiency of several assisted reproduction-related procedures, such as sperm processing, in vitro embryo production and artificial insemination. Bull fertility is ultimately a collective projection of the ability of a series of ejaculates to endure sperm processing stress, and achieve fertilisation of the oocyte and production of a viable and well-developing embryo. In this concept, the assessment of sperm functional and molecular characteristics is key to bull fertility diagnostics and prognostics. Among others, functional features linked to sperm plasma membrane, acrosome and DNA integrity are usually assessed as a measure of the ability of sperm to express the phenotypes that will allow them to maintain their homeostasis and orchestrate-in a strict temporal manner-the course of events that will enable the delivery of their genetic content to the oocyte upon fertilisation. Nevertheless, measures of sperm functionality are not always adequate indicators of bull fertility. Nowadays, advancements in the field of molecular biology have facilitated the profiling of several biomolecules in male gametes. The molecular profiling of bovine sperm offers a deeper insight into the mechanisms underlying sperm physiology and, thus, can reveal novel candidate markers for bull fertility prognosis. In this review, the importance of three organelles (the nucleus, the plasma membrane and the acrosome) for the characterisation of sperm fertilising capacity and bull fertility is discussed at functional and molecular levels. In particular, information about sperm head morphometry, chromatin structure, viability as well as the ability of sperm to capacitate and undergo the acrosome reaction are presented in relation to the cryotolerance of male gametes and bull fertility. Finally, major spermatozoal coding and non-coding RNAs, and proteins that are involved in the above-mentioned aspects of sperm functionality are also summarised.
Topics: Cattle; Male; Animals; Semen; Fertility; Spermatozoa; Acrosome; Insemination, Artificial; Sperm Motility
PubMed: 37567681
DOI: 10.1016/j.animal.2023.100795 -
Reproduction in Domestic Animals =... Oct 2022Ultrasound technology has led to new lines of research in equine reproduction, and it has helped to greatly improve clinical diagnosis and reproductive outcomes in... (Review)
Review
Ultrasound technology has led to new lines of research in equine reproduction, and it has helped to greatly improve clinical diagnosis and reproductive outcomes in equine practice. This review aims to discuss the potential clinical uses and new approaches of ultrasonography in equine reproduction. Doppler modalities are usually used to evaluate the vascularization of the follicles, corpus luteum (CL), and the uterus in the mare for diagnostic purposes. Inclusion of Doppler ultrasound in artificial insemination and embryo transfer programs could improve the reproductive outcome of these techniques. Better selection of recipients based on CL functionality, early pregnancy diagnosis 7-8 days postovulation of the donor before flushing or diagnosis of mares with endometritis with pathological increases of blood flow are examples of clinical applications in the mare. In the stallion, colour Doppler ultrasound has improved the diagnostic potential of B-mode ultrasound, improving the differential diagnosis of pathologies such as testicular torsion (decrease or absence of blood flow in the cord) and orchitis (increased blood flow in the cord). The incorporation of pulsed Doppler ultrasound into the reproductive evaluation of the stallion has enabled early identification of stallions with testicular dysfunction, thus allowing administration of timely treatment and subsequent improvements of the fertility prognosis for these animals. In addition, this technique has been used in the monitoring of patients undergoing medical and surgical treatments, thus verifying their efficacy. Recently, computer-assisted pixel analysis using specific software has been performed in research work in order to semi-quantitatively evaluate the vascularization (colour and power Doppler) and echotexture of different organs. These softwares are now being developed for clinical purposes, as is the case with Ecotext, a computer program developed for the evaluation of testicular echotexture, providing information on testicular functionality.
Topics: Animals; Corpus Luteum; Female; Horses; Insemination, Artificial; Male; Pregnancy; Reproductive Medicine; Ultrasonography; Ultrasonography, Doppler, Color
PubMed: 35748405
DOI: 10.1111/rda.14192 -
Fertility and Sterility Jun 2021
Topics: Female; Fertilization in Vitro; Humans; Insemination, Artificial, Homologous; Male; Pregnancy; Pregnancy Rate; Sperm Count; Spermatozoa
PubMed: 33867136
DOI: 10.1016/j.fertnstert.2021.03.013 -
Frontiers in Endocrinology 2020Anti-Müllerian hormone reflects the continuum of the functional ovarian reserve, and as such can predict ovarian response to gonadotropin stimulation and be used to... (Review)
Review
Anti-Müllerian hormone reflects the continuum of the functional ovarian reserve, and as such can predict ovarian response to gonadotropin stimulation and be used to individualize treatment pathways to improve efficacy and safety. However, consistent with other biomarkers and age-based prediction models it has limited ability to predict live birth and should not be used to refuse treatment, but rather to inform counselling and shared decision making. The use of absolute clinical thresholds to stratify patient phenotypes, assess discordance and individualize treatment protocols in non-validated algorithms combined with the lack of standardization of assays may result in inappropriate classification and sub-optimal clinical decision making. We propose that holistic baseline phenotyping, incorporating antral follicle count and other patient characteristics is critical. Treatment decisions driven by validated algorithms that use ovarian reserve biomarkers as continuous measures, reducing the risk of misclassification, are likely to improve overall outcomes for our patients.
Topics: Adult; Anti-Mullerian Hormone; Female; Fertilization in Vitro; Humans; Insemination, Artificial; Male; Ovary; Ovulation Induction; Pregnancy
PubMed: 33362720
DOI: 10.3389/fendo.2020.606744 -
Animal Reproduction Science May 2024Successful artificial breeding underpins rapid genetic and production gains in animal agriculture. In sheep, artificial insemination with frozen semen is performed via... (Review)
Review
Successful artificial breeding underpins rapid genetic and production gains in animal agriculture. In sheep, artificial insemination with frozen semen is performed via intrauterine laparoscopy as frozen-thawed spermatozoa do not traverse the cervix in sufficient numbers for high fertility and transcervical insemination is anatomically impossible in most ewes. Historically, laparoscopic artificial insemination has always been considered reasonably successful, but recent anecdotal reports of poor fertility place it at risk of warning adoption. Understanding the male, female and environmental factors that influence the fertility of sheep is warranted if the success of artificial insemination is to be improved and genetic progress maximised for the sheep industry. This review details the current practice of laparoscopic AI in sheep. It explores the effects of semen quantity and quality, the ewe, her preparation, and environmental conditions, on the fertility obtained following laparoscopic artificial insemination.
Topics: Animals; Insemination, Artificial; Sheep; Female; Laparoscopy; Male; Pregnancy; Semen Preservation
PubMed: 38547814
DOI: 10.1016/j.anireprosci.2024.107453 -
The Journal of Reproduction and... Feb 2021Over the past few decades, the luteolytic dose of prostaglandin F (PGF) and its analogs, used to synchronize estrus for fixed-time insemination in dairy cattle, have... (Review)
Review
Over the past few decades, the luteolytic dose of prostaglandin F (PGF) and its analogs, used to synchronize estrus for fixed-time insemination in dairy cattle, have remained unchanged. Given the beneficial effects of PGF on a young corpus luteum and on multiple ovulations in a fixed-time insemination protocol, and its therapeutic abortive effects on multiple ovulations in pregnant cows, we propose the use of a double PGF dose or two PGF treatments 24 hours apart. Ultrasonography procedures serve to identify luteal structures and may therefore help to determine the best PGF dose to improve the fertility of high-producing dairy cows.
Topics: Animals; Cattle; Dairying; Dinoprost; Dose-Response Relationship, Drug; Drug Administration Schedule; Estrus Synchronization; Female; Insemination, Artificial; Luteolysis; Pregnancy
PubMed: 33162429
DOI: 10.1262/jrd.2020-101 -
Theriogenology Dec 2020This study aimed to determine whether the insemination site and dose with cryopreserved sperm of reproductively normal mares affect the sperm population in uterine tubes...
This study aimed to determine whether the insemination site and dose with cryopreserved sperm of reproductively normal mares affect the sperm population in uterine tubes and the intensity of endometrial inflammatory response. Experimental subjects were estrous mares inseminated, in the mid-uterine body (Body) or the tip of the uterine horn (Tip), ipsilateral to the dominant follicle, with one 0.5 mL straw with 50 × 10 sperm (50) or with eight straws with 50 × 10 sperm/straw (400). Mares were slaughtered 2 h, 4 h and 12 h after artificial insemination (AI) and randomly assigned to following groups: Body 50 (n = 19) (2 h, 4 h or 12 h); Tip 50 (n = 29) (2 h, 4 h, or 12 h); Body 400 (n = 24) (2 h, 4 h, or 12 h); Tip 400 (n = 21) (2 h, 4 h, or 12 h). A Control group (n = 16) was not inseminated. After slaughter, uterine tubes were separated from uterus, and uteri and tubes flushed with phosphate-buffered saline (PBS). After flushing, an endometrial sample was collected from ipsilateral and contralateral horns and mid-uterus body for further histopathological examination. A sample of each uterine tube flushing was examined for sperm count, and a sample of each uterine flushing was used for polymorphonuclear neutrophils (PMNs) count. Data were analyzed using PROC GLM from SASv9.4. Insemination time, site, sperm dose, and their interactions were considered independent variables and sperm and PMNs numbers dependent variables. Deep horn insemination increased ipsilateral uterine tube sperm number without an increase in the inflammatory reaction compared with the uterine body insemination. The higher the insemination dose, the higher the uterine tubes' sperm number and inflammatory reaction, with a quicker resolution. In conclusion, the insemination site and dose affected sperm in the uterine tubes, while post-insemination time and dose influenced the inflammatory reaction.
Topics: Animals; Cryopreservation; Female; Horses; Insemination, Artificial; Male; Sperm Count; Sperm Transport; Spermatozoa; Uterus
PubMed: 32961353
DOI: 10.1016/j.theriogenology.2020.09.021 -
Journal of Animal Science Feb 2020Efforts to understand biological functions and develop management schemes specific to Bos indicus-influenced cattle raised in tropical and subtropical environments are... (Review)
Review
Efforts to understand biological functions and develop management schemes specific to Bos indicus-influenced cattle raised in tropical and subtropical environments are critical to meet the increasing global demand for protein. In the United States, B. indicus breeds are mostly used to generate B. indicus × B. taurus crosses with increased thermal and parasite tolerance, while retaining some productive characteristics of B. taurus cattle. Although crossbreeding represents a proven strategy to improve cattle adaptation almost immediately, research has also attempted to identify B. taurus genetics that can withstand subtropical and tropical climates. Reduced milk production and delayed reproductive maturation appear to be related with tropical adaptation of B. taurus breeds, as a means to conserve energy under stressful conditions and limited nutrition. Moreover, longevity may be the ultimate adaptation response to unfavorable environments, and retention of bulls and heifers from proven cows is the recommended strategy to improve longevity in B. indicus-influenced herds. Besides selection for longevity, other aspects should be considered when planning reproductive management in tropical and subtropical regions. Bos indicus and B. taurus breeds have multiple differences pertaining to reproductive function, including age at puberty, ovarian dynamics, and pregnancy development. Nutritional strategies such as the stair-step regimen, and use of exogenous progesterone (P4) inserts are options to hasten puberty attainment of late-maturing B. indicus-influenced heifers. Yet, limited pharmacological alternatives are available for reproductive management of B. indicus-influenced females in the United States, which rely on GnRH-based protocols not specifically designed to the reproductive function of B. indicus breeds. In contrast, hormonal protocols based on exogenous P4, estradiol esters, and equine chorionic gonadotropin are available for use in B. indicus females in South America. These include protocols tailored to prepubertal heifers, anestrous cows, and cycling nulliparous or parous females, which often yield pregnancy rates of 50% to fixed-time artificial insemination. The global dairy industry also faces similar challenges in increasing demand and production as the beef industry. Selection of cows capable of sustaining optimal milk yield, reproductive success, and health status in hot and humid conditions is essential for optimal dairy production in subtropical and tropical regions.
Topics: Adaptation, Physiological; Animals; Breeding; Cattle; Estradiol; Female; Gonadotropin-Releasing Hormone; Insemination, Artificial; Longevity; Male; Ovary; Pregnancy; Pregnancy Rate; Progesterone; Reproduction; Tropical Climate
PubMed: 31955201
DOI: 10.1093/jas/skaa015