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Artificial Insemination (artificial + insemination)
Selected AbstractsEffect of Oxytocin Treatment on Artificial Insemination with Frozen,Thawed Semen in Murciano,Granadina GoatsREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2009MP Viudes-de-Castro Contents The site where the semen is deposited appears to be one of the most important factors affecting pregnancy of inseminated goats. In Murciano,Granadina (MG) goats, post-cervical insemination is achieved in a limited number of females. An effective way to increase fertility rate could be by increasing post-cervical inseminations. Effect of exogenous oxytocin application to facilitate the cervical penetration and its effect on kidding rate and prolificacy in MG goats were investigated. Oestrus was synchronized using progesterone-impregnated sponges for 11 days. Females were randomly divided into three groups (n = 190) and received either an i.v. injection of 100 or 200 IU of oxytocin or saline solution 15 min before being inseminated. Data on semen deposition depth were recorded for each animal using a catheter scaled in centimetres (up to 4 cm). Depth of semen deposition was affected by the oxytocin treatment (p < 0.05). Oxytocin enhanced cervical passage only with the dose of 200 IU compared with the control group, increasing the deposition depth (2.9 cm vs 1.9 cm). No significant effect of oxytocin treatment on kidding rate and prolificacy was detected. Depth of semen deposition affected kidding rate (p < 0.01). In conclusion, oxytocin treatment improved the depth of semen deposition in AI of MG goats, but kidding rate and prolificacy was not affected. More studies must be conducted to assess the minimal effective dose required for sufficient cervical dilation, and to determine the effects of such doses of oxytocin on uterine motility, sperm transport and fertility in goats. [source] Case of Pregnancy in Two Cows with Unicorn Horn of the Uterus either by Artificial Insemination at Ipsilateral or Embryo Transfer at Contralateral Corpus Luteum in the OvaryREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2008C Moriyama Contents Two Holstein heifers and a cow were diagnosed with White Heifer Disease by ultrasonography. Case 1 was a 14 month-old heifer with aplasia of both sides of the uterine horn. In case 2, a primiparous cow and case 3, an 18 month-old heifer, both showed aplasia of the right uterine horn. Case 2 became pregnant by artificial insemination at ipsilateral ovulatory follicle and corpus luteum in the left ovary, while case 3 became pregnant by embryo transfer at 7 days after oestrus with contralateral corpus luteum in the right ovary. [source] The Effect of Post-Ovulatory Artificial Insemination on Sow Reproductive PerformanceREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2003CD Castagna Contents In order to increase reproductive performance, sows are usually inseminated several times during oestrus. In practice, this results in a significant number of sows receiving one or more post-ovulatory inseminations. This study was carried out to determine the percentage of sows that receive one or more post-ovulatory inseminations and the effect of such treatment on reproductive performance. The results were analysed from a total of 1298 sows on two farms. It was observed that more than 70% of the sows received at least one post-ovulatory insemination and approximately 20% received two or more. There was no observed effect on the rate of return to oestrus, farrowing rate or litter size (p > 0.05). [source] Quality Parameters for Alpaca (Vicugna pacos) Semen are Affected by Semen Collection ProcedureREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2010KM Morton Contents Artificial insemination (AI) is poorly developed in camelids owing to the difficulty in collecting high quality semen and the highly viscous nature of the semen. Semen collected by artificial vagina (AV) is often of low quality and must be improved before any further development of AI technology can occur. The present study investigated the effects of adding a cervix-like stricture to the AV, presence of females, collecting semen into Androhep®, skim-milk or Tris diluents, and catalase supplementation (0, 100, 200 or 600 units/ml) of Tris diluent on alpaca semen quality parameters. The addition of a cervix-like stricture increased mating length (p < 0.05), whilst the presence of females during semen collection did not improve semen quality parameters (p > 0.05). Collection of semen into Tris diluent improved sperm motility (58.0 ± 11.9%) compared with the control (34.0 ± 10.8%; p < 0.05), Androhep® (33.5 ± 10.7%) and skim-milk diluents (28.2 ± 10.4%). Semen viscosity was reduced by collection into Androhep® (4.6 ± 1.7 mm) and skim-milk diluents (3.6 ± 1.3 mm) compared with Tris diluent (5.7 ± 2.1 mm) and no collection medium (9.3 ± 3.5 mm; p < 0.05). Tris diluent supplemented with 100, 200 or 600 units/ml catalase increased semen viscosity (5.0 ± 3.2 and 4.9 ± 3.2 mm). Collection of alpaca semen by AV into Tris diluent increased semen quality facilitating further development of AI technology in alpacas. [source] Aspects of the reproductive biology and breeding management of Asian and African elephants Elephas maximus and Loxodonta africanaINTERNATIONAL ZOO YEARBOOK, Issue 1 2006T. B. HILDEBRANDT Elephants possess many unique qualities, including some that relate directly to their reproductive biology. Thus, comparative studies on elephants provide valuable information to the growing biological database for extant mammals. Left undisturbed, Asian Elephas maximus and African Loxodonta Africana elephants reproduce well in the wild. It is ironic then that most captive populations face possible,extinction'because of historically poor reproductive performance. Some of the problems with breeding elephants in captivity are logistical but others, like ovarian and uterine pathologies and bull infertility, have management-related aetiology. Through advances in endocrine monitoring and ultrasound imaging techniques, we are beginning to understand some of the complex mechanisms controlling reproductive function in elephants. Several reproductive characteristics appear to be unique to the taxon, such as luteal steroidogenic function, follicular development patterns, pituitary gonadotrophin secretion, a 22 month-long gestation and musth (in ,,). One example is the,double LH surge'occurring 3 weeks apart during the follicular or non-luteal phase of the cycle, with only the second surge inducing ovulation. These qualities have at times both enhanced and hampered efforts to understand and control reproduction. We have learned that techniques developed for domestic or laboratory species are not always directly applicable to elephants. However, the recent success of artificial insemination based on new ultrasound and endocrine methodology offers hope that establishing selfsustaining populations is possible. This paper reviews our current knowledge of elephant reproduction and how it is being used to aid species conservation for maximal reproductive efficiency and enhancement of genetic management. [source] Effect of male age on sperm traits and sperm competition success in the guppy (Poecilia reticulata)JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 1 2010C. GASPARINI Abstract Deleterious mutations can accumulate in the germline with age, decreasing the genetic quality of sperm and imposing a cost on female fitness. If these mutations also affect sperm competition ability or sperm production, then females will benefit from polyandry as it incites sperm competition and, consequently, minimizes the mutational load in the offspring. We tested this hypothesis in the guppy (Poecilia reticulata), a species characterized by polyandry and intense sperm competition, by investigating whether age affects post-copulatory male traits and sperm competition success. Females did not discriminate between old and young males in a mate choice experiment. While old males produced longer and slower sperm with larger reserves of strippable sperm, compared to young males, artificial insemination did not reveal any effect of age on sperm competition success. Altogether, these results do not support the hypothesis that polyandry evolved in response to costs associated with mating with old males in the guppy. [source] Sperm binding properties and secretory activity of the bovine oviduct immediately before and after ovulationMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 1 2008Edita Sostaric Abstract The possibility that differences in hormonal regimes between the two oviducts in the cow around ovulation affects secretory activity of the oviduct epithelial cells and/or sperm,oviduct binding was studied. Oviducts were collected immediately after slaughter at 6 hr before to 5 hr after timed ovulation of 14 normally cyclic cows that had been inseminated (n,=,6) or not (n,=,8) and material obtained from the same cows was processed in three ways. First, in vivo, after artificial insemination of the cows, low numbers of sperm cells (approx. 15 per oviduct) were found within the entire oviducts as observed by scanning electron microscopy (SEM). Almost all sperm were located in the isthmus and then only on ciliated cells and showed without exception fully matured, intact morphology. Secretory activity of noninseminated oviduct epithelia was induced after ovulation which was most predominant in the pockets of the ipsi-lateral ampulla compared to the contra-lateral ampulla (P,<,0.01). Second, ex vivo, explants dissected from oviducts of the noniseminated cows were incubated with sperm. In all cases, the sperm bound to the explants in a similar pattern as observed in vivo and this binding was strictly fucose-dependent. The main difference with in vivo experiments was the high numbers of sperm bound at any site of the oviduct (,3,000 cells per mm2) indicating the high sperm binding capacity of the oviduct epithelia. Ovulation induced a striking drop in sperm binding capacity in the oviducts and was most pronounced in the isthmus (,1,300 cells per mm2; P,<,0.001) and to a lesser extent in the ampulla (,2,000 cells per mm2, P,<,0.01). Third, in vitro, pieces of tissue dissected from oviducts of the noninseminated cows were cultured to mono-layers. Culturing epithelial cells resulted in loss of their normal morphological appearance. In all cases, the sperm binding capacity in monolayers was very low (<50 cells per mm2) when compared to corresponding explants (P,<,0.0001). Sperm binding to monolayers originating from the isthmus (<25 cells per mm2) was lower than in those from the ampulla (40,50 cells per mm2; P,<,0.01) and remained similar after ovulation. In all three approaches, no significant differences were found in sperm,oviduct binding characteristics and sperm-distribution in the ipsi- versus contra-lateral oviducts. This indicates, that systemic endocrine changes around ovulation rather than specific oviduct changes at the ipsi,lateral oviduct induce secretion in oviduct epithelial cells, and thus induce sperm release. Mol. Reprod. Dev. 75: 60,74, 2008. © 2007 Wiley-Liss, Inc. [source] Expression of insulin-like growth factors systems in cloned cattle dead within hours after birthMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 4 2007Shijie Li Abstract Cloning by somatic nuclear transfer is an inefficient process in which many of the cloned animals die shortly after birth and display organ abnormalities. In an effort to determine the possible roles IGFs played in neonatal death and organ abnormalities, we have examined expression patterns of eight genes in insulin-like growth factor (IGF) systems (IGF1, IGF2, IGF1R, IGF2R, IGFBP-1, IGFBP-2, IGFBP-3, and IGFBP-4) in six organs (heart, liver, spleen, lung, kidney, and brain) of both neonatal death cloned bovines (n,=,9) and normal control calves (n,=,3) produced by artificial insemination (AI) using real-time quantitative RT-PCR. The effect of the age of the fibroblast donor cell on the gene expression profiles was also investigated. Aberrant expressions of six genes (IGF2, IGF1R, IGF2R, IGFBP-2, IGFBP-3, and IGFBP-4) were found in some studied tissues, but the expression of two genes (IGF1 and IGFBP-1) had similar levels with the normal controls. For the studied genes, kidney was the organ that was most affected (five genes) by gene downregulation, whereas spleen was the organ that was not affected. The two upregulation genes were in brain, but both of downregulation and upregulation were found in the heart, liver, and lung. The expression of three genes (IGF2R, IGFBP-4, and IGF2) in some tissues showed significant differences between AF cell-derived and FF cell-derived clones. Our results suggest that aberrations in gene expression within IGF systems were found in most cloned bovine tissues of neonatal death. Because IGF systems play an important role in embryo development and organogenesis, the aberrant transcription patterns detected in these clones may contribute to the defects of organs reported in neonatal death of clones. Mol. Reprod. Dev. 74: 397,402, 2007. © 2006 Wiley-Liss, Inc. [source] Roles of antioxidants on prolonged storage of avian spermatozoa in vivo and in vitroMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2003Christelle Bréque Abstract This review focuses on natural and assisted prevention against lipid peroxidation in avian spermatozoa. The presence of high levels of n-6 polyunsaturated fatty acids (PUFAs) in the plasma membrane creates favorable conditions for the formation of peroxidative products, a major cause of membrane damage which may ultimately impair male fertility. However, a complex antioxidant system involving vitamin C, vitamin E and GSH is naturally present in avian semen. Coupled with a battery of enzymatic defenses (e.g., SOD, GSH-Px either Se- or non-Se-dependent), this system acts to prevent or restrict the formation and propagation of peroxides. The presence of specialized sites dedicated to prolonged sperm storage in avian females raises the question of durable protection of sperm membranes against peroxidation. Preliminary observations have revealed the presence of a specific antioxidant system at these sites in which vitamin C could exert a major role. From a practical standpoint, the extensive use of artificial insemination in poultry, along with the emergence in some species of workable techniques to cryopreserve spermatozoa, demand better control of peroxidation occurring in the plasma membrane of spermatozoa before or during storage. Dietary supplementation with vitamin E is effective in limiting lipid peroxidation of sperm plasma membranes, both in chickens and turkeys. In addition, organic Se with or without vitamin E stimulates Se-GSH-Px activity in seminal plasma. Preliminary observations in female chickens have also revealed the effectiveness of dietary supplementation with vitamin E, organic selenium or both to sustain fertility in aging flocks. Mol. Reprod. Dev. 66: 314,323, 2003. © 2003 Wiley-Liss, Inc. [source] Protein profiles of bovine placenta derived from somatic cell nuclear transferPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 16 2005Hong Rye Kim Abstract Practical application of animal cloning by somatic cell nuclear transfer (SCNT) has been hampered by an extremely low success rate. To address whether placental dysfunction in SCNT causes fetal loss during pregnancy, we have used a global proteomics approach using 2-DE and MS to analyze the differential protein patterns of three placentae from the afterbirth of cases of postnatal death, derived from SCNT of Korean Native cattle, and three normal placentae obtained from the afterbirth of fetuses derived from artificial insemination. Proteins within a pI range of 4.0,7.0 and 6.0,9.0 were analyzed separately by 2-DE in triplicate. A total of approximately 2000 spots were detected in placental 2-DE gels stained with CBB. In the comparison of normal and SCNT samples, 60 spots were identified as differentially expressed proteins, of which 33 spots were up-regulated proteins in SCNT placentae, while 27 spots were down-regulated proteins. Most of the proteins identified in this analysis appeared to be related with protein repair or protection, cytoskeleton, signal transduction, immune system, metabolism, extracellular matrix and remodeling, transcription regulation, cell structure or differentiation and ion transport. One of up-regulated proteins in SCNT was TIMP-2 protein known to be related to extracellular matrix and remodeling during pregnancy. Western blot analysis showed an increased level of TIMP-2 in SCNT placenta compared to normal. Our results revealed composite profiles of key proteins involved in abnormal placenta derived from SCNT, and suggested expression abnormality of these genes in SCNT placenta, resulting in fetal losses following SCNT. [source] Expression of Progesterone Receptor in the Utero-tubal Junction After Intra-uterine and Deep Intra-uterine Insemination in SowsREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2010P Tummaruk Contents The aim of this study was to investigate the expression of progesterone receptor (PR) in the utero-tubal junction (UTJ) of sows at 24 h after intra-uterine insemination (IUI) and deep intra-uterine insemination (DIUI) compared with conventional artificial insemination (AI) in pigs. Fifteen multiparous sows were used: AI (n = 5), IUI (n = 5) and DIUI (n = 5). The sows were inseminated with a single dose of diluted semen during the second oestrus after weaning at 6,8 h prior to ovulation (AI: 3000 × 106 spermatozoa, IUI: 1000 × 106 spermatozoa and DIUI: 150 × 106 spermatozoa). The UTJ was collected and subject to immunohistochemical staining using avidin-biotin immunoperoxidase technique with mouse monoclonal antibody to PR. In the oviductal part of the UTJ, the intensity of PR in the tunica muscularis and the proportion of PR-positive cells in the surface epithelium after DIUI were lower than AI (p < 0.05). The intensity and the proportion of PR-positive cells between AI and IUI in all compartments of the UTJ did not differ significantly (p > 0.05). When comparing between tissue compartments, prominent staining was observed in the muscular layer of the UTJ. It could be concluded that the expression of PR in the UTJ prior to fertilization after DIUI with a reduced number of spermatozoa was lower than that after AI. This might influence sperm transportation and the fertilization process. [source] First Service Pregnancy Rates Following Post-AI Use of hCG in Ovsynch and Heatsynch Programmes in Lactating Dairy CowsREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2010H Karami Shabankareh Contents Lactating dairy cows (n = 667) at random stages of the oestrous cycle were assigned to either ovsynch (O, n = 228), heatsynch (H, n = 252) or control (C, n = 187) groups. Cows in O and H groups received 100 ,g of GnRH agonist, i.m. (day 0) starting at 44 ± 3 days in milk (DIM), and 500 ,g of cloprostenol, i.m. (day 7). In O group, cows received 100 ,g of GnRH (day 9) and were artificially inseminated without oestrus detection 16,20 h later. In H group, cows received 1 mg oestradiol benzoate (EB) i.m., 24 h after the cloprostenol injection and were artificially inseminated without oestrus detection 48,52 h after the EB injection. Cows in C group were inseminated at natural oestrus. On the day of artificial insemination (AI), cows in all groups were assigned to subgroups as follows: human Chorionic Gonadotrophin (O-hCG) (n = 112), O-saline (n = 116), H-hCG (n = 123), H-saline (n = 129), C-hCG (n = 94) and C-saline (n = 93) subgroups. Cows in hCG and saline subgroups received 3000 IU hCG i.m. and or 10 ml saline at day 5 post-AI (day 15), respectively. Pregnancy status was assessed by palpation per rectum at days 40 to 45 after AI. The logistic regression model using just main effects of season (summer and winter), parity (primiparous and pluriparous), method1 (O, H and C) and method2 (hCG and saline) showed that all factors, except method1, were significant. Significant effects of season (p < 0.01), hCG and parity (p < 0.01), and a trend of parity and season (p < 0.1) were detected. A clear negative effect of warm period on first service pregnancy rate was noted (p < 0.01). The pregnancy rate was the lowest in the H protocol during warm period (p < 0.05). Treatment with hCG 5 days after AI significantly improved pregnancy rates in those cows that were treated with the H protocol compared with saline treatments (41.5% vs 24.8%; p < 0.01). O and H were more effective in primiparous than in pluriparous cows (46.1% vs 29.9%; p < 0.1 and 43.6% vs 24.6%; p < 0.01). First service pregnancy rates were higher in primiparous hCG-treated than in pluriparous hCG-treated cows (57.9% vs 32.3%; p < 0.01). The pregnancy rate was higher for the hCG-treated cows compared with saline-treated cows during warm period (37.9% vs 23.6%; p < 0.001). [source] Efficacy of Ovsynch Protocol with Antiprolactin Treatment for Timed Artificial Insemination During Non-breeding Seasons in Yaks (Poephagus grunniens L.)REPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2010M Sarkar Contents An attempt was undertaken to investigate the efficacy of Ovsynch protocol for timed artificial insemination (TAI) with or without Norprolac (antiprolactin) treatment during non-breeding season (winter months) in yaks (n = 25). During non-breeding season, plasma prolactin profile has been reported high due to cold and nutritional stress. The Norprolac dose of i.m. administration was standardized for prolactin suppression. Three different doses viz. 2.5, 5.0 and 7.5 mg were attempted and the dose of 7.5 mg Norprolac i.m. per animal was found to be suitable for suppression of prolactin levels up to 30 h. Ovsynch treatment with Norprolac induced more number of oestrous symptoms per animal (4.8 vs 2.1), higher LH peak concentration (24.01 vs 16.16 ng/ml), longer duration of LH surge (6.8 vs 5.2 h) and higher conception rate (70 vs 30%) in Ovsynch plus Norprolac treated animals compared with animals treated with Ovsynch alone. Therefore, this study clearly indicates the opportunity for practical application of the Ovsynch plus Norprolac protocol for TAI in yaks during non-breeding seasons. [source] Number of Spermatozoa in the Crypts of the Sperm Reservoir at About 24 h After a Low-Dose Intrauterine and Deep Intrauterine Insemination in SowsREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2010P Tummaruk Contents The aim of this study was to investigate the number of spermatozoa in the crypts of the utero-tubal junction (UTJ) and the oviduct of sows approximately 24 h after intrauterine insemination (IUI) and deep intrauterine insemination (DIUI) and compared with that of conventional artificial insemination (AI). Fifteen crossbred Landrace × Yorkshire (LY) multiparous sows were used in the experiment. Transrectal ultrasonography was performed every 4 h to examine the time of ovulation in relation to oestrous behaviour. The sows were inseminated with a single dose of diluted fresh semen by the AI (n = 5), IUI (n = 5) and DIUI (n = 5) at approximately 6,8 h prior to the expected time of ovulation, during the second oestrus after weaning. The sperm dose contained 3000 × 106 spermatozoa in 100 ml for AI, 1,000 × 106 spermatozoa in 50 ml for IUI and 150 × 106 spermatozoa in 5 ml for DIUI. The sows were anaesthetized and ovario-hysterectomized approximately 24 h after insemination. The oviducts and the proximal part of the uterine horns (1 cm) on each side of the reproductive tracts were collected. The section was divided into four parts, i.e. UTJ, caudal isthmus, cranial isthmus and ampulla. The spermatozoa in the lumen in each part were flushed several times with phosphate buffer solution. After flushing, the UTJ and all parts of the oviducts were immersed in a 10% neutral buffered formalin solution. The UTJ and each part of the oviducts were cut into four equal parts and embedded in a paraffin block. The tissue sections were transversely sectioned to a thickness of 5 ,m. Every fifth serial section was mounted and stained with haematoxylin and eosin. The total number of spermatozoa from 32 sections in each parts of the tissue (16 sections from the left side and 16 sections from the right side) was determined under light microscope. The results reveal that most of the spermatozoa in the histological section were located in groups in the epithelial crypts. The means of the total number of spermatozoa in the sperm reservoir (UTJ and caudal isthmus) were 2296, 729 and 22 cells in AI, IUI and DIUI groups, respectively (p < 0.01). The spermatozoa were found on both sides of the sperm reservoir in all sows in the AI and the IUI groups. For the DIUI group, spermatozoa were not found on any side of the sperm reservoir in three out of five sows, found in unilateral side of the sperm reservoir in one sow and found in both sides of the sperm reservoir in one sow. No spermatozoa were found in the cranial isthmus, while only one spermatozoon was found in the ampulla part of a sow in the IUI group. In conclusion, DIUI resulted in a significantly lower number of spermatozoa in the sperm reservoir approximately 24 h after insemination compared with AI and IUI. Spermatozoa could be obtained from both sides of the sperm reservoir after AI and IUI but in one out of five sows inseminated by DIUI. [source] Ultrasonographic and Endocrine Evaluation of Three Regimes for Oestrus and Ovulation Synchronization for Sheep in the SubtropicsREPRODUCTION IN DOMESTIC ANIMALS, Issue 6 2009A Ali Contents This study aimed to evaluate three regimes for oestrus and ovulation synchronization in Farafra ewes in the subtropics. During autumn, 43 ewes were assigned to (i) controlled internal drug releasing (CIDR)-eCG group, treated with CIDR for 12 days and eCG at insert withdrawal, n = 13; (ii) PGF2,-PGF2, group, treated with two PGF2, injections at 11 days interval, n = 14; and (iii) GnRH-PGF2,-GnRH group, treated with GnRH, followed 5 days later with PGF2, and 24 h later with a second GnRH, n = 16. Oestrus-mating detection was carried out at 4 h intervals starting on day 0 [the day of CIDR withdrawal (CIDR-eCG group), the day of second PGF2, treatment (PGF2,-PGF2, group) and the day of PGF2, treatment (GnRH-PGF2,-GnRH group)]. Ovarian dynamics was monitored by ultrasound every 12 h beginning on day 0 and continued for 4 days. Blood samples were obtained daily for progesterone (P4) and oestradiol 17, (E2) estimation starting on day 0 and continued for 4 days. The obtained results showed that, oestrus expression, ovulation and conception were greater (p < 0.05) in CIDR-eCG and PGF2,-PGF2, groups than in GnRH-PGF2,-GnRH group. All ewes of PGF2,-PGF2, group presented, on day of second PGF2, injection with mature CL (P4 > 2.0 ng/ml), compared to 42.9% in GnRH-PGF2,-GnRH group (p = 0.01). The peak of oestrus occurred 32,52, 48,60 and 28,96 h after the end of treatment in CIDR-eCG, PGF2,-PGF2, and GnRH-PGF2,-GnRH groups, respectively. Ovulation started 48 h after treatment in all groups and extended for 24, 36 and 48 h for CIDR-eCG, PGF2,-PGF2, and GnRH-PGF2,-GnRH groups, respectively. Results demonstrated that oestrus and ovulation synchronization could be efficiently achieved in Farafra ewes using either CIDR-eCG or PGF2,-PGF2, regimes; however, the GnRH-PGF2,-GnRH treatment induced a more spread oestrus and ovulation that may make the protocol inadequate for timed artificial insemination. [source] Prolonged Duration of Fertility of Dog OvaREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009T Tsutsui Contents The fertile period for natural mating in dogs extends from before ovulation until day 5 post ovulation (PO) and involves a delay in oocyte maturation until 2,3 days PO and viability of secondary oocytes for 48,60 h or more. Spermatozoa do not enter the uterus after vaginal insemination in late oestrus. Cervical closure appears to occur on average 5 days PO, but conception may occur following intrauterine artificial insemination (IUAI) up to 8 days PO. Therefore, the present study was conducted to clarify the duration of fertility of canine ova. Using IUAI at 6, 7, 8 and 9 days PO (n = 5 bitches each) conception rates were 100%, 71.4%, 37.5% and 0%, respectively, with an average litter resorption rate of 30.8%, and with mean litter sizes and times to delivery PO being 4.3 ± 1.6 and 64.3 ± 0.3 days, 4.0 ± 1.4 and 66.3 ± 0.4 days, and 2.5 and 68 days for IUAI at 6, 7 and 8 days, respectively. The high pregnancy rates with IUAI at 6 and 7 days PO confirm that many canine oocytes are fertile at 4,5 days after maturation. The high rate of resorption was presumably because of aging of ova or asynchrony between embryonic development and the intrauterine environment. [source] Factors Affecting the Quality of Cryopreserved Buffalo (Bubalus bubalis) Bull SpermatozoaREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2009SMH Andrabi Contents Storage of buffalo (Bubalus bubalis) bull semen in the cryopreserved state is discussed in this article. Fertility rate in buffalo following artificial insemination with frozen,thawed semen is reviewed. To better understand the freezability of bubaline spermatozoa, the available data on biochemical components and the activity of specific enzymes of semen/spermatozoa are given. Moreover, the major factors that may influence the post-thaw viability and fertility of buffalo spermatozoa are examined in detail. In addition, suggestions for improvement in cryogenic procedures for buffalo spermatozoa are also given. [source] Body Condition Change Ante- and Postpartum, Health and Reproductive Performance in German Holstein CowsREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2009M Hoedemaker Contents The effects of body condition score (BCS) change and status ante- and postpartum (pp) on health and reproductive performance in 234 German Holstein cows from eight dairy farms were evaluated. BCS was determined from 6 weeks antepartum until 20 weeks pp in 2-week intervals. Three and 5 weeks pp progesterone concentrations in blood serum were determined to detect the presence of luteal tissue as an indicator of cyclicity. The incidence of various diseases, percent cycling cows, reproductive measures and culling rate were assessed. Data were subjected to logistic regression to account for possible herd and lactation number effects. Cows with a low BCS status (<3.0) at calving and during early lactation (4,10 weeks pp) were at a higher risk of suffering from lameness (OR 2.9,9.4), not being cycling at 3 and/or 5 weeks pp (OR 2.24,3.99) and being culled (OR 2.56,2.79) than cows in better body condition (,3.0) In addition, cows with a low BCS status at parturition were at a higher risk of developing endometritis (OR 2.95) and becoming pregnant later than 105 days pp (OR 5.92) than cows with a BCS , 3.0. At 10 weeks pp, the risk of dystocia (OR 4.10) or retained placenta (OR 2.78) at the preceding calving and not being pregnant at 200 days pp (OR 2.42) was higher in cows with a BCS < 3.0 than with a BCS , 3.0. Cows with no BCS loss antepartum were more likely to have an interval from calving to first artificial insemination of <80 days and <105 days open, to be cycling at 3 and 5 weeks pp and to be pregnant at 200 days pp than cows with a BCS loss of >0.25 (OR 2.44,6.67). Furthermore, cows with no BCS loss from calving to 4 weeks pp had a lower risk of suffering from displaced abomasum than cows with a slight or a severe BCS loss (OR 0.09,0.07 respectively). In conclusion, our results suggest that body condition loss during the antepartal period affected BCS status at parturition and to a certain extent during lactation which was linked to a higher incidence of reproductive disorders and lameness, a higher culling rate and lower reproductive performance. [source] Case of Pregnancy in Two Cows with Unicorn Horn of the Uterus either by Artificial Insemination at Ipsilateral or Embryo Transfer at Contralateral Corpus Luteum in the OvaryREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2008C Moriyama Contents Two Holstein heifers and a cow were diagnosed with White Heifer Disease by ultrasonography. Case 1 was a 14 month-old heifer with aplasia of both sides of the uterine horn. In case 2, a primiparous cow and case 3, an 18 month-old heifer, both showed aplasia of the right uterine horn. Case 2 became pregnant by artificial insemination at ipsilateral ovulatory follicle and corpus luteum in the left ovary, while case 3 became pregnant by embryo transfer at 7 days after oestrus with contralateral corpus luteum in the right ovary. [source] Autologous Whole Ram Seminal Plasma and its Vesicle-free Fraction Improve Motility Characteristics and Membrane Status but not In Vivo Fertility of Frozen,Thawed Ram SpermatozoaREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2007R El-Hajj Ghaoui Contents Motility characteristics (assessed subjectively and with computer-assisted semen analysis) and membrane status (after staining with chlortetracycline) of washed and non-washed frozen,thawed ram spermatozoa were evaluated after incubation in buffer and buffer containing autologous whole seminal plasma or one of its two fractions: the pellet of membrane vesicles obtained by ultracentrifugation (and used at three times normal protein concentration) or the vesicle-free supernatant fraction. Whole seminal plasma and supernatant, but not membrane vesicles, improved the motility characteristics of spermatozoa after 3 and 6 h of post-thaw incubation compared with the control buffer. Resuspension and incubation with whole seminal plasma, supernatant or membrane vesicles lowered the proportion of acrosome-reacted frozen,thawed spermatozoa compared with the control buffer. Unwashed frozen,thawed semen from three rams, incubated with autologous whole seminal plasma or its fractions and inseminated using cervical or intrauterine artificial insemination, had no effect on pregnancy rates of ewes in synchronized oestrus. However, fertility was higher after laparoscopic than cervical insemination (44.9 vs 12.3%, p < 0.001). In conclusion, resuspension and incubation of frozen,thawed ram spermatozoa in autologous whole seminal plasma or its vesicle-free supernatant fraction improved their motility characteristics and, with membrane vesicles, membrane status, but these benefits were not reflected in improved fertility after cervical or intrauterine insemination. [source] Effect of Insemination,Ovulation Interval and Addition of Seminal Plasma on Sow Fertility to Insemination of Cryopreserved SpermREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2007M Abad Contents In swine, the use of frozen-thawed (FT) sperm for artificial insemination (AI) is limited because of poor sow fertility, possibly associated with a post-thaw capacitation-like status resulting in fewer fully viable sperm. Sow fertility to AI with FT sperm may improve with deeper deposition of sperm within the female tract, insemination very close to ovulation, or reversal of cryocapacitation by seminal plasma (SP). We performed two experiments to examine these suggestions. In experiment 1, 122 multiparous Yorkshire sows received 600 IU equine chorionic gonadotrophin at weaning and 5 mg pLH 80 h later to control time of ovulation. The predicted time of ovulation (PTO) was 38 h after pLH injection. Thereafter, sows were assigned on the basis of parity to a single AI of FT sperm at 2 h before PTO, or at 12 h before PTO, or FT sperm supplemented with 10% SP at 12 h before PTO. Control sows received fresh semen at 12 h before PTO. All semen doses were adjusted to 3 × 109 live cells and deposited into the cervix. Experiment 2 employed 99 multiparous crossbred sows and repeated the treatments of experiment 1 except that all FT inseminations were intrauterine. In both experiments, farrowing rates were lower (p < 0.01) following FT inseminations with no effect of time of insemination or of supplemental SP. In experiment 1, litter size was smaller following FT insemination (p < 0.05), but no effect on litter size was evident in experiment 2. Supplemental SP had no effect on litter size in either experiment. The lack of effect of either SP or timing of FT insemination on sow fertility suggests that the non-lethal sperm cryoinjury affecting fertility involves more than just cryocapacitation. [source] Measurement of Faecal Progesterone Metabolites and its Application for Early Screening of Open Cows Post-inseminationREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2007B Kornmatitsuk Contents The present study investigated the changes of serum progesterone (P4) and its faecal metabolites in pregnant and non-pregnant cows (Expt 1) and the feasibilty of using faecal P4 metabolites for early screening of open cows post-insemination (Expt 2). In Expt 1, seven crossbred Holstein,Friesian (HF) cows were studied. Serum and faecal samples were collected once daily from the day of artificial insemination (AI) until 25 days after AI. In Expt 2, 27 crossbred HF inseminated cows were employed. Serum and faecal samples were obtained on the day of AI (day 0) and on days 19,22 post-insemination. Enzyme immunoassay measurements of serum P4 and faecal P4 metabolites were established. The low detection limit of the assay was 0.01 ng/ml and the amount of P4, resulting in a 50% reduction in the initial binding value, was 1.07 ng/ml. The intra- and inter-assay coefficients of variation were <8% and <14%, respectively. A positive correlation between the levels of serum P4 and faecal P4 metabolites was found in every single cow (r = 0.73,0.88, p < 0.001) and pooled data (r = 0.78, p < 0.001). The estimated value of faecal P4 metabolites at 100 ng/g of faeces was equal to the serum P4 levels of 1 ng/ml. The accuracies of pregnancy and non-pregnancy diagnosis based on the analyses of faecal P4 metabolites between day 0 and days 19,22 post-insemination, were 67% and 100%, respectively. In conclusion, the measurement of faecal P4 metabolites can be a potentially alternative method for early screening of open cows post-insemination with the same accuracy and precision, as measured by serum P4 assay. [source] Comparative IFN- , Secretion after Hatching by Bovine Blastocysts Derived Ex Vivo and Completely Produced In VitroREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2007JA Neira Contents The interferon-tau (IFN- ,) secretion levels after hatching by bovine blastocysts derived from in vitro maturated oocytes (Group A) and from in vivo (Group B) were investigated considering embryo quality. Only very homogeneous blastocysts of excellent or good quality were considered from day 7 of culture (Group A) and day 7 after artificial insemination with frozen-thawed from the same bull used for in vitro fertilization (Group B). All embryos were individually cultured into a 50 ,l droplet of synthetic oviduct fluid medium with 10% fetal calf serum. After 24-h culture both Group A (n =44) and B (n = 40) secreted <54 pm IFN- ,. After 48-, 72-, 96- and 120-h culture, Group A daily secreted 143 ± 24 pm IFN- , (n = 19) vs 85 ± 12 pm IFN- , (n = 21) for Group B (p < 0.01), 491 ± 128 pm IFN- , (n = 29) vs 216 ± 37 pm IFN- , (n = 23) (NS), 499 ± 135 pm IFN- , (n = 26) vs 353 ± 93 pm IFN- , (n = 21) (NS), 559 ± 136 pm IFN- , (n = 22) vs 333 ± 75 pm IFN- , (n = 20) (NS), respectively. Taken all together during 5 days, Group A produced per embryo 1690 ± 290 pm IFN- , (n = 22) vs 982 ± 182 pm IFN- , (n = 20) for Group B (p < 0.05). For all culture time there were sizable percentages of embryos that did not produce concentrations of IFN- , above a certain cut-off level, and as such were not used to compute the means. In respect of the embryo quality whatever the groups after days 7,12 of culture, IFN- , secretions were 1815 ± 453 pm (n = 10) for the embryos of excellent quality vs 1356 ± 200 pm (n = 28) for those of good quality (NS) and 360 ± 188 pm (n = 4) (p < 0.05) for embryos of fair quality. A positive relationship between IFN- , production and in vitro development of quality I embryos was observed, whatever the embryos origins and, the embryos completely produced in vitro secreted more IFN- , than the embryos produced in vivo. [source] Can We Increase the Estimative Value of Semen Assessment?*REPRODUCTION IN DOMESTIC ANIMALS, Issue 2006H Rodríguez-Martínez Contents Estimating the fertility of a semen sample or of the male from where it has been collected by simple assessment of in vitro sperm characteristics is still difficult, owing to the variable correlations that laboratory results achieve with in vivo fertility. A major reason behind these variations is the fact that the ejaculate and the artificial insemination (AI)-doses it generates are composed of a diverse sperm population. Such heterogeneity is reflected both in differences of intactness of attributes needed for fertilization, such as motility or morphology, but also in the relative ability of spermatozoa to prevail fertile over time, handling and exposure to different stimuli, all of which account for innate variations in fertilizing ability among doses, ejaculates and sires. However, methods are already available to select sub-populations of intact spermatozoa which can be tested for their degree of competence for fertilization and whose estimative power is promising, allowing the elimination of cases of sub-fertility, particularly in bovine. Examples of these methods are the separation of viable spermatozoa by swim-up or discontinuous gradient centrifugation, followed by testing the ability of the selected spermatozoa to dose-response/time sustain capacitation and acrosome reaction induction. Finding how large a sperm population with non-compensable attributes for fertilization and ability to display and sustain stimuli is, perhaps by a quick screening of membrane integrity and stability by multi-parametric methods, would allow, provided the particular male produces this sub-population in a repeatable manner, for a better estimation of fertility. [source] Second Oestrus Synchronization and Precocious Embryo Viability after Puberty Induction in Gilts by the Use of Gonadotrophin TreatmentREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2005V Do Lago Contents The use of exogenous gonadotrophins in puberty inducement and ovulation synchronization is a technique that has a positive influence on the management of swine. The purpose of this study was to verify the effects of a second gonadotrophin treatment [equine chorionic gonadotrophin (eCG) and luteinizing hormone (LH), intramuscularly (i.m.)] upon the second oestrus synchronization and fertility in gilts. Seventy-one NAIMA® (Pen Ar Lan) gilts had their first oestrus (puberty inducement) induced by a hormonal treatment (eCG and LH). Then, they were randomly distributed into two treatments, with (T1) and without (C) gonadotrophin treatment at the second oestrus. The animals were fed with a single ration (16% of crude protein and 3286.73 kcal ME/kg), and timed artificial insemination performed at the second oestrus. Gilts were slaughtered for embryo recovery and ovary examination about 5 days after insemination. There was no evidence of a difference in the percentage of the second oestrus expression (T1 , 90.90% and C , 86.84%), the duration of the oestrus cycle (T1 , 19.62 ± 0.82 days and C , 19.67 ± 4.14 days), the percentage of follicular cysts (T1 , 15.15% and C , 18.42%) and number of ovulations (T1 , 14.60 ± 5.7 and C , 13.23 ± 4.8) between treatments (p > 0.05). However, the hormonal treatment (T1) showed minor oestrus dispersion and embryo viability (T1 , 8.4 ± 5.6 and C , 11.2 ± 4.6) (p < 0.05). These results indicate that the better synchronization and expression of the second oestrus when using gonadotrophins (eCG and LH) is followed by a lower embryo viability, which is probably the consequence of the heterogeneous follicle recruitment during the injection of eCG. [source] Assessment of Progesterone Concentration Using Enzymeimmunoassay, for Early Pregnancy Diagnosis in Sheep and GoatsREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2003CM Boscos Contents The objective of this study was to determine a value of serum progesterone (P4) concentration, assessed using an enzymeimmunoassay (EIA), for the early distinction between pregnant and non-pregnant ewes and goats. Adult, non-lactating ewes of Chios (n=53), Berrichon (n=30) and Sfakia (n=45) breeds were synchronized during the breeding season with progestagens and gonadotrophins and mated to fertile rams (Experiment I). Adult, lactating goats of Swiss breeds (Alpine and Saanen, n=104) and indigenous Greek breed (n=45) were synchronized during the transitional season with progestagens, PGF2, and gonadotrophins. Cervical artificial insemination (AI) with fresh semen was applied once, 42,44 h after sponge removal (Experiment II). Jugular blood samples were collected on day 19 after sponge removal (ewes) or on day 21 after AI (goats) and serum P4 concentration was determined by EIA. Progesterone concentrations ,1.0, ,1.5, ,2.5 and ,4.0 ng/ml were tested as indicative of pregnancy. Pregnancy diagnosis was verified on birth. In the case of sheep, using a discriminatory level of 2.5 ng/ml, overall accuracy of pregnancy diagnosis was 91.4% and predictive value of negative and positive diagnoses were 98.3 and 85.3%, respectively. In the case of goats, predictive value of negative diagnosis was 95.8 and 94.0% and predictive value of positive diagnosis 71.3 and 71.7%, for 1.5 and 2.5 ng/ml, respectively; overall accuracy was 79.2% using either level. The other discriminatory levels tested did not improve these results. A significant positive correlation was observed between P4 concentration and the number of lambs or kids born, and further analysis indicated that this relationship is not a simple linear function. Based on the results of this study, P4 concentrations of 2.5 ng/ml in the case of ewes and 1.5,2.5 ng/ml in the case of goats, determined with EIA, are proposed as discriminatory levels between pregnant and non-pregnant animals, at an interval of one oestrous cycle after service. [source] Investigation of Cervical Patency and Uterine Appearance in Domestic Cats by Fluoroscopy and ScintigraphyREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2002K Chatdarong Contents The cervical patency of six domestic female cats was monitored under sedation by infusion of contrast medium (Omnipaque) into the cranial vagina during early oestrus, mid-oestrus, late oestrus and interoestrus or a radiopharmaceutical (99mTc-HSA) during mid- and interoestrus in a non-ovulatory oestrous cycle. The transport of the contrast medium or the radiopharmaceutical through the cervix and within the uterine horns was observed under fluoroscopy and with the aid of scintigraphy. In three of the queens, transcervical transport of contrast medium was demonstrated in all stages of oestrus, in one queen during mid-oestrus, late oestrus and 1 day after oestrus, and in two queens only during late oestrus. The relations between the cervical patency to the contrast medium and the oestrous behaviour, cornification of the vaginal cells and the serum oestradiol-17, concentration were evaluated, and a relationship was found between the cervical patency and the degree of vaginal cornification. Transcervical transport of the radiopharmaceutical was observed in three queens during mid-oestrus. When the cervix was open, hysterography under a fluoroscope and hysteroscintigraphy were performed. The fluoroscopic and scintigraphic recordings revealed the patterns of the uterine contractions during oestrus in both ascending and descending directions, and the movement of the uterine contents back and forth between the uterine horns. The hysterograms were classified according to the shape of the uterine horns and the appearance of the endometrial lining. Spiral-shaped uterine horns with a smooth inner contour were observed in two queens, and a corkscrew appearance with irregular filling defects in the uterine lumen was shown in two queens that had developed subclinical cystic endometrial hyperplasia. These findings demonstrated that fluids or particles deposited in the cranial vagina of the cat can be transported into the uterus during some stages of the oestrous cycle. The fluoroscopic and scintigraphic techniques developed in this study may be further modified to permit more detailed studies of uterine contractile patterns and sperm transport in the feline female reproductive tract. Hysterography proved useful to diagnose uterine disease. The information on cervical patency is of value also for the development of techniques for artificial insemination in this species, and should be studied also in the ovulatory cycle. [source] Relationship between Sperm Response to Glycosaminoglycans in vitro and Non-return Rates of Swedish Dairy AI BullsREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2000A Januskauskas Contents In this study, the relations between fertility (56-day non-return rates, 56-day NRR) after artificial insemination (AI) and bull sperm characteristics post-thaw, after swim-up and after co-incubation with heparin (Hep) and hyaluronan (HA), respectively, were determined, attempting to determine if such a procedure could be of value to evaluate the potential fertilizing ability of frozen-thawed AI bull spermatozoa. Spermatozoa from 20 semen batches derived from 20 Swedish Red and White AI bulls ranging widely in their field fertility after AI (55,79% 56-day NRRs) were evaluated with regards to post-thaw motility, membrane integrity, and migration through a simple swim-up procedure. Sperm viability and capacitation status were evaluated by two different vital staining procedures and chlortetracycline hydrochloride staining. Sperm motility and membrane integrity post-thaw (e.g. indicators of sperm viability) were significantly correlated (r = 0.53, p < 0.05 and r = 0.59, p < 0.01, respectively) with fertility. Heparin (5 µg/ml) significantly (p lt; 0.001) increased the frequencies of capacitation and acrosome-reaction (AR) among swim-up separated spermatozoa, whereas HA at a concentration of 50 ng/ml did not have any significant capacitating effect. The incidences of capacitated or AR-spermatozoa following Hep-treatment were not correlated with fertility. On the other hand, the percentage of viable spermatozoa was significantly (p < 0.001) lower in Hep-treated samples than in control and HA-treated samples and was significantly (r = 0.49, p < 0.05) correlated with fertility after AI (56-day NRR). The results indicate that the percentage of viable spermatozoa after swim-up separation and heparin-exposure from a selected population of AI bulls were significantly and positively related to the AI fertility of the donors and thus could be used as a parameter to determine the fertilizing ability of frozen,thawed AI bull spermatozoa. [source] Playing the Stockmarket in Tana TorajaTHE AUSTRALIAN JOURNAL OF ANTHROPOLOGY, Issue 1 2000Robyn Thompson This paper describes the players and the play in a weekly stockmarket in Tana Toraja. South Sulawesi, where up to 600 buffalo bulls are bought and sold for exorbitant prices by any standards. These prices are partly determined by external, global economic forces. The buffaloes are all intended for sacrifice in elaborate funerals. Although contributed by individuals or families they are conceived as part of mana. the common wealth of tongkonan. the origin houses of the Toraja. Live bulls cannot be given away but are able to be lent in ceremonial exchanges at funerals. After sacrifice, their raw meat is distributed to participants in the funeral in a version of potlatch. Bulls mediate all exchange. apart from mundane commodity exchange, and are liquid assets. A mature black bull is an object of general equivalence able to be exchanged as payment for certain symbolic objects. In the past the production, distribution and circulation of buffaloes, both on the hoof and as meat, were controlled by the nobility. Buffaloes were said to be in finite supply. They derived from the Upperworld and accompanied the ancestors of the Toraja nobility to this world and were replenished through the ritual of the ways of the ancestors. Now the advent of the market has democratised buffaloes. There has been a dispersion of wealth and the power that the bulls embody. Any man,noble, commoner or former slave-who has sufficient cash is able to buy and sell buffaloes: to have a share in the stockmarket. The marketplace has become a new field of power play, one where innovative methods are being found for increasing the supply of buffaloes by importing hundreds of inferior quality buffaloes and by a program of artificial insemination which has been instigated by the local government. In the parlance of Wall Street this is a bull market. [source] Male and Female Effects on the In Vitro Production of Bovine EmbryosANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2004G. A. Palma Summary A 3-year study was carried out to evaluate male and female effects on the efficiency of an in vitro fertilization (IVF) programme. The semen of different bulls used for artificial insemination was tested for the in vitro production of transferable blastocysts. The fertilization capacity was recorded for each bull. Bovine oocytes were matured in vitro, fertilized with frozen/thawed semen of 63 individual bulls and cultured during 8 days. The semen of one bull was used as control. The percentage of cleavage (36.3,93.4%) and blastocysts on day 7 (6.9,51.2%) varied from bull to bull. Despite high variability, blastocysts were produced with the semen of all bulls in the first trial. Moreover, oocytes fertilized with 85% of tested bulls reached a blastocyst rate not different to the control bull. The correlation coefficients of six bulls showed no significant male effect but an influence of oocytes on the cleavage rate (F -value 0.38, P > 0.05, and 12.4, P < 0.001, respectively). The development to blastocysts on day 7 was significantly influenced by sperms and also oocytes and session (P < 0.01), but no combined interaction was observed between female and male. It is concluded that transferable embryos can be produced in vitro in the first trial with frozen/thawed semen of 63 tested bulls. The results show different capacities of bulls to produce embryos and high male and female effects on the efficiency of an IVF programme. [source] | ||||||||||||||||