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1.
J Dairy Sci ; 106(10): 6816-6833, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37500448

ABSTRACT

This study investigated the effects of acacia (extract of Acacia mearnsii) and sainfoin (Onobrychis viciifolia) as condensed tannin (CT)-rich sources on ruminal and manure methane (CH4) emissions in comparison with non-CT silages characterized by different contents of the cell wall and water-soluble carbohydrates. In a 3 × 6 incomplete Latin square design, 30 Holstein cows (63 ± 23 d in milk; mean ± SD; 33.8 ± 7.6 kg of milk per day, body weight 642 ± 81 kg) were provided with ad libitum access to 1 of 6 total mixed rations comprising 790 g of silage and 210 g of concentrate per kilogram of dry matter (DM). The silages were either rich in sainfoin [neutral detergent fiber (NDF): 349 g/kg of DM], perennial ryegrass (NDF: 420 g/kg of DM), or red clover (NDF: 357 g/kg of DM). Each silage was supplemented with 20 g/kg (of total diet DM) of acacia or straw meal. Feed intake and milk yield were recorded daily. Milk composition and ruminal fluid characteristics and microbiota were analyzed. The individual ruminal CH4 production was determined using the GreenFeed system, and CH4 emissions from the manure of cows fed the same diets were measured in a parallel experiment over 30 d at 25°C using a dynamic flux chamber. The CT sources did not reduce CH4 yield or emission intensity. Acacia reduced milk production (from 26.3 to 23.2 kg/d) and DM intake (from 19.7 to 16.7 kg/d) when supplemented with ryegrass, and both CT sources reduced the milk protein content and yield. Acacia supplementation and ryegrass silage reduced the ruminal acetate:propionate ratio. Furthermore, during acacia treatment, the abundance of Methanobrevibacter archaea tended to be lower and that of Thermoplasmata was higher. Acacia reduced the CH4 emissions from manure for the ryegrass group by 17% but not for the sainfoin and clover groups. Feeding sainfoin silage resulted in the lowest manure-derived CH4 emissions (-47% compared with ryegrass). In conclusion, acacia reduced ruminal CH4 production by 10%, but not emission intensity, and the mitigation effect of sainfoin depended on the silage to which it was compared. Because mitigation was partially associated with animal productivity losses, careful evaluation is required before the implementation of tanniferous feeds in farm practice.


Subject(s)
Acacia , Proanthocyanidins , Female , Cattle , Animals , Manure , Lactation , Silage/analysis , Acacia/metabolism , Methane/metabolism , Digestion , Zea mays/metabolism , Diet/veterinary , Nutrients , Rumen/metabolism
2.
Theriogenology ; 169: 76-88, 2021 Jul 15.
Article in English | MEDLINE | ID: mdl-33940218

ABSTRACT

The ongoing mass extinction of animal species at an unprecedented rate is largely caused by human activities. Progressive habitat destruction and fragmentation is resulting in accelerated loss of biodiversity on a global scale. Over decades, captive breeding programs of non-domestic species were characterized by efforts to optimize species-specific husbandry, to increase studbook-based animal exchange, and to improve enclosure designs. To counter the ongoing dramatic loss of biodiversity, new approaches are warranted. Recently, new ideas, particularly the application of assisted reproduction technologies (ART), have been incorporated into classical zoo breeding programs. These technologies include semen and oocyte collection, artificial insemination, and in-vitro embryo generation. More futuristic ideas of advanced ART (aART) implement recent advances in biotechnology and stem-cell related approaches such as cloning, inner cell mass transfer (ICM), and the stem-cell-associated techniques (SCAT) for the generation of gametes and ultimately embryos of highly endangered species, such as the northern white rhinoceros (Ceratotherium simum cottoni) of which only two female individuals are left. Both, ART and aART greatly depend on and benefit from the rapidly evolving cryopreservation techniques and biobanking not only of genetic, but also of viable cellular materials suitable for the generation of induced pluripotent stem cells (iPSC). The availability of cryopreserved materials bridges gaps in time and space, thereby optimizing the available genetic variability and enhancing the chance to restore viable populations.


Subject(s)
Biological Specimen Banks , Endangered Species , Animals , Biodiversity , Female , Perissodactyla , Reproductive Techniques, Assisted/veterinary
5.
Reprod Fertil Dev ; 32(5): 468-473, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32172777

ABSTRACT

The success of invitro embryo production (IVEP) in horses has increased considerably during recent years, but little is known about the effect of the speed of invitro embryo development. Blastocysts (n=390) were produced by intracytoplasmic sperm injection of IVM oocytes from warmblood mares, cryopreserved, thawed and transferred into recipient mares on Days 3, 4, 5 or 6 after ovulation. The time required for invitro-produced (IVP) embryos to reach the blastocyst stage was recorded (Day 7 vs Day 8). The likelihood of foaling was affected by the speed of invitro embryo development and recipient day after ovulation at transfer. The odds ratio for foaling was ~0.63 for transfer of Day 8 (46%) compared with Day 7 (56%) IVP blastocysts. The highest likelihood of pregnancy (72%) and foaling (60%) was observed when IVP blastocysts were transferred to recipient mares on Day 4 after ovulation. Finally, the sex (colt:filly) ratio was higher after transfer of Day 7 (71%:29%) than Day 8 (54%:46%) IVP blastocysts, suggesting that the speed of embryo development is sex dependent. In conclusion, the speed of invitro embryo development in our IVEP system affects the likelihood of foaling and the sex of the foal.


Subject(s)
Blastocyst/physiology , Embryo Transfer/veterinary , Horses/physiology , In Vitro Oocyte Maturation Techniques/veterinary , Sperm Injections, Intracytoplasmic/veterinary , Animals , Animals, Newborn , Embryo Culture Techniques/veterinary , Female , Live Birth/veterinary , Male , Pregnancy , Retrospective Studies , Sex Ratio , Time Factors
6.
Equine Vet J ; 51(4): 446-450, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30269336

ABSTRACT

BACKGROUND: In vitro embryo production (IVEP) is increasingly popular but data assessing the outcome of transferred embryos are scarce. OBJECTIVES: To determine the likelihood of pregnancy and embryonic loss after transfer of frozen-thawed IVP embryos and identify factors influencing success. STUDY DESIGN: Retrospective clinical study. METHODS: Blastocysts (n = 261) were produced from immature oocytes of Warmblood mares (n = 116) by Intracytoplasmic Sperm Injection (ICSI) and in vitro culture, and cryopreserved. Thawed IVP embryos were transferred into recipient mares on day 4, 5 or 6 after ovulation. The influence of donor mare (age, reproductive history), recipient mare (age, reproductive status, management; in-house vs. outpatient, day post-ovulation), embryo (interval from ICSI to blastocyst formation) and management factors (season when ovum pickup was performed, year and method of transfer) on likelihood of pregnancy and embryonic loss was examined, and the developmental stage of the IVP embryo at the time of transfer was estimated. RESULTS: The percentage of mares pregnant 7-10, 23 and 37 days after transfer was 56% (147/261), 49% (129/261), and 48% (124/261), respectively. Development of IVP embryos after transfer equated to day 5 or 6 in vivo embryos. With the exception of year of transfer, none of the factors had an impact on the likelihood of pregnancy or embryonic loss. Nevertheless, the likelihood of pregnancy tended to be lower for IVP embryos from infertile mares or when embryos were transferred into recipient mares on day 6 after ovulation rather than on day 4 or 5. Finally, the diameter of the embryonic vesicle 7 days post transfer was lower for pregnancies that were lost compared to those that were maintained. MAIN LIMITATIONS: Small sample size in some of the donor and recipient mare categories. CONCLUSIONS: Cryopreserved IVP embryos should be transferred into recipient mares on day 4 or 5 after ovulation and a slower rate of post transfer vesicle expansion indicates a higher risk of subsequent embryonic loss The Summary is available in Portuguese - see Supporting Information.


Subject(s)
Abortion, Veterinary , Cryopreservation/veterinary , Embryo Transfer/veterinary , Horses/physiology , Animals , Blastocyst , Embryo, Mammalian , Female , Horses/embryology , Humans , Pregnancy , Retrospective Studies
7.
Clin Transl Radiat Oncol ; 15: 7-12, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30582015

ABSTRACT

The aim of this current study was to assess whether the tumour grade and molecular subtypes have influenced local control in the whole breast hypofractionated radiotherapy (HRT) over standard radiotherapy (SRT) in early breast node negative cancer patients by a retrospective control group study. Data of 215 patients treated with hypofractionated radiotherapy at our institution from 2008 to 2011 were prospectively collected and then compared with 215 pts treated with SRT in a control group study. The local relapse free survival (LRFS) in both arms was compared on the basis of variables defined by tumour grade (Nottingham Grading System), and Molecular subtypes. Kaplan-Meier method was applied to estimate the LRFS in both groups. Chi-squared and univariate Cox proportional hazards model were conducted for all variables in both groups to assess the impact on local control. Statistical significance was assumed at P < .05. Statistical significant variables at univariate analysis were then included in multivariate Cox proportional hazards model. The median follow up duration was 9.5 years (7-13 yrs); the Kaplan Meyer 8 year LRFS did not reach any statistical significant difference between the two groups (P = . 836). At univariate Cox analysis tumour grade 3 was significantly related to local relapse only in the SRT group (P = .041) while, among molecular subtypes, no differences were found for all groups; for Her2 + noL no difference was found (P = .233). Multivariate analysis confirmed Her2 non-luminal subtype as an independent variable for local relapse regardless the fractionation arm (P = .045). Breast cancer subtypes show a different radiosensitivity, which is independent by fractionation.

8.
Biochim Biophys Acta Mol Basis Dis ; 1864(6 Pt A): 2131-2142, 2018 06.
Article in English | MEDLINE | ID: mdl-29601977

ABSTRACT

Leigh syndrome (LS) associated with cytochrome c oxidase (COX) deficiency is an early onset, fatal mitochondrial encephalopathy, leading to multiple neurological failure and eventually death, usually in the first decade of life. Mutations in SURF1, a nuclear gene encoding a mitochondrial protein involved in COX assembly, are among the most common causes of LS. LSSURF1 patients display severe, isolated COX deficiency in all tissues, including cultured fibroblasts and skeletal muscle. Recombinant, constitutive SURF1-/- mice show diffuse COX deficiency, but fail to recapitulate the severity of the human clinical phenotype. Pigs are an attractive alternative model for human diseases, because of their size, as well as metabolic, physiological and genetic similarity to humans. Here, we determined the complete sequence of the swine SURF1 gene, disrupted it in pig primary fibroblast cell lines using both TALENs and CRISPR/Cas9 genome editing systems, before finally generating SURF1-/- and SURF1-/+ pigs by Somatic Cell Nuclear Transfer (SCNT). SURF1-/- pigs were characterized by failure to thrive, muscle weakness and highly reduced life span with elevated perinatal mortality, compared to heterozygous SURF1-/+ and wild type littermates. Surprisingly, no obvious COX deficiency was detected in SURF1-/- tissues, although histochemical analysis revealed the presence of COX deficiency in jejunum villi and total mRNA sequencing (RNAseq) showed that several COX subunit-encoding genes were significantly down-regulated in SURF1-/- skeletal muscles. In addition, neuropathological findings, indicated a delay in central nervous system development of newborn SURF1-/- piglets. Our results suggest a broader role of sSURF1 in mitochondrial bioenergetics.


Subject(s)
Central Nervous System/growth & development , Disease Models, Animal , Leigh Disease/genetics , Membrane Proteins/genetics , Mitochondrial Proteins/genetics , Sus scrofa/genetics , Animals , Animals, Genetically Modified , Animals, Newborn , Behavior, Animal , CRISPR-Cas Systems , Cells, Cultured , Down-Regulation , Electron Transport Complex IV/metabolism , Female , Fibroblasts , Gene Editing , Gene Knockout Techniques , Humans , Jejunum/pathology , Leigh Disease/pathology , Male , Mitochondria/pathology , Muscle, Skeletal/cytology , Muscle, Skeletal/pathology , Nuclear Transfer Techniques , Primary Cell Culture
9.
Clin Transl Radiat Oncol ; 7: 43-48, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29594228

ABSTRACT

BACKGROUND AND PURPOSE: To investigate the hypothesis on low-dose bath exposure related to radiation-induced nausea and vomiting (RINV) in adjuvant breast volumetric modulated arch therapy (VMAT). METHODS AND MATERIALS: A total of 106 consecutive breast cancer patients (pts) treated with adjuvant radiotherapy (RT) with VMAT from January 2013 to May 2016 were evaluated retrospectively. For each pt, a planning CT was reimported and the coeliac plexus and gastroesophageal junction with gastric mouth (GEJCPs) were contoured as a new organ at risk (OAR) in the upper abdominal area. RINV was associated with Dmax and Dmean to GEJCPs. Univariate analysis with χ2, t-test, and Pearson's covariance was used for statistical analysis. RESULTS: Of 106 pts, 64% complained of acute RINV according to the Common Terminology Criteria for Adverse Events (CTCAE) version 4.03. RINV was related to Dmax > 10 Gy and Dmean > 3 Gy to GEJCPs (P < 0.005). The radiation breast side and planning target volume (PTV) correlated with RINV. CONCLUSIONS: RINV in VMAT breast radiotherapy could be a new emerging acute side effect due to a low dose bath to upper abdominal structures such as the GEJCPs. A Dmax < 10 Gy and Dmean < 3 Gy to GEJCPs should be constrained in VMAT planning to minimize RINV risk in breast radiotherapy.

10.
Cell Dev Biol ; 5(2)2016 Aug.
Article in English | MEDLINE | ID: mdl-27774366

ABSTRACT

Human Embryonic Stem Cells (hESCs) potentially offer a unique in vitro model to study how an adverse environment during the early developmental stages post-fertilization can affect the physiology of the undifferentiated embryonic stem cells existing in the early embryo and predispose to long term effects on the offspring, according to the Developmental Origins of Health and Disease (DOHaD) concept. A number of unfavourable conditions can affect the development of the early embryo inducing oxidative stress both in vivo, for instance in gestational diabetes and in vitro, when embryos are derived from Assisted Reproductive Technologies (ART). Therefore, the aim of this study was the development of a novel in vitro model to analyse the effects of oxidative stress and the antioxidant response against Reactive Oxygen Species (ROS) in embryonic stem cells in comparison with somatic cells, fibroblasts and endothelial cells. To this purpose we designed an in vitro protocol based on hydrogen peroxide (H2O2) treatment of 72 h, in order to better resemble the period of embryonic development from the early cleavages to the blastocyst stage. We demonstrate that H2O2 treatment induces the modification of crucial oxidative stress biomarkers like ROS and lipid peroxidation levels, and mobilizes several antioxidant enzymes through NFkß translocation. Moreover we show differences between somatic and embryonic cells in their antioxidant response towards H2O2 induced damage. Therefore this study presents a promising in vitro model to investigate the effects of oxidative stress conditions on early human embryonic cells.

11.
Am J Transplant ; 15(2): 358-70, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25612490

ABSTRACT

Galactosyl-transferase KO (GalT-KO) pigs represent a potential solution to xenograft rejection, particularly in the context of additional genetic modifications. We have performed life supporting kidney xenotransplantation into baboons utilizing GalT-KO pigs transgenic for human CD55/CD59/CD39/HT. Baboons received tacrolimus, mycophenolate mofetil, corticosteroids and recombinant human C1 inhibitor combined with cyclophosphamide or bortezomib with or without 2-3 plasma exchanges. One baboon received a control GalT-KO xenograft with the latter immunosuppression. All immunosuppressed baboons rejected the xenografts between days 9 and 15 with signs of acute humoral rejection, in contrast to untreated controls (n = 2) that lost their grafts on days 3 and 4. Immunofluorescence analyses showed deposition of IgM, C3, C5b-9 in rejected grafts, without C4d staining, indicating classical complement pathway blockade but alternate pathway activation. Moreover, rejected organs exhibited predominantly monocyte/macrophage infiltration with minimal lymphocyte representation. None of the recipients showed any signs of porcine endogenous retrovirus transmission but some showed evidence of porcine cytomegalovirus (PCMV) replication within the xenografts. Our work indicates that the addition of bortezomib and plasma exchange to the immunosuppressive regimen did not significantly prolong the survival of multi-transgenic GalT-KO renal xenografts. Non-Gal antibodies, the alternative complement pathway, innate mechanisms with monocyte activation and PCMV replication may have contributed to rejection.


Subject(s)
Boronic Acids/therapeutic use , Complement C1 Inhibitor Protein/therapeutic use , Galactosyltransferases/genetics , Graft Survival/physiology , Heterografts , Kidney Transplantation , Plasma Exchange , Pyrazines/therapeutic use , Animals , Animals, Genetically Modified , Autoimmune Diseases , Bortezomib , Cytomegalovirus/physiology , Galactosyltransferases/deficiency , Gene Knockout Techniques , Immunity, Innate/physiology , Immunosuppressive Agents/therapeutic use , Kidney/surgery , Kidney/virology , Models, Animal , Papio anubis , Sus scrofa , Virus Replication/physiology
12.
Stem Cell Rev Rep ; 10(5): 712-24, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24906426

ABSTRACT

Amniotic fluid (AF) is a source of multipotent mesenchymal stem cells (MSCs), very promising cells for tissue engineering in clinical application. The aim of this work was to isolate and characterize cells isolated from bovine AF as alternative sources of primitive multipotent stem cells in a species that could be a large-animal model for biomedical and biotechnology researches. Samples were recovered, at slaughterhouse, from 39 pregnant cows at different trimesters of pregnancy and cells were cultured in vitro. At passages (P) 3 and 7 differentiation towards chondrogenic, osteogenic and adipogenic lineages was induced. Flow cytometry analysis for CD90, CD105, CD73, CD44, CD34, CD45 and CD14 was performed, immunocytochemistry (ICC) for Oct4, SSEA4, α-SMA, Vimentin, N- and E- Cadherin and CK and qPCR analysis for OCT4, NANOG and SOX2 were carried out. The cell yield was significantly higher in the first trimester compared to the second and the third one (P < 0.05). Cells were isolated from 25/39 samples and cell population appeared heterogeneous. Two main cell types were identified in samples from all trimesters: round- (RS) and spindle-shaped (SS) cells. 17/25 samples showed both populations (mixed, MX). Both cell types showed MSC-markers and differentiation capability with some variability related to the passages. The SS-population also expressed low levels of stemness markers such as NANOG and SSEA4 but not OCT4. Bovine AF shows a heterogeneous cell population containing also MSCs, multipotent cells that represent an intermediate stage between embryonic stem cells and adult ones.


Subject(s)
Amniotic Fluid/cytology , Mesenchymal Stem Cells/cytology , Pregnancy, Animal/physiology , Animals , Cattle , Cell Differentiation , Cell Separation , Cells, Cultured , Female , Flow Cytometry , Multipotent Stem Cells/cytology , Pregnancy
13.
Neurodegener Dis ; 13(4): 246-54, 2014.
Article in English | MEDLINE | ID: mdl-24157939

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that occurs in two clinically indistinguishable forms: sporadic (SALS) and familial (FALS), the latter linked to several gene mutations, mostly inheritable in a dominant manner. Nearly 20% of FALS forms are linked to mutations in the Cu/Zn superoxide dismutase (SOD1) gene. Research on ALS relies on transgenic models and particularly on mice carrying a glycine-to-alanine conversion at the 93rd codon (G93A) of the hSOD1 gene. Although G93A transgenic mice have been widely employed in clinical trials and basic research, doubts have been recently raised from numerous reliable sources about their suitability to faithfully reproduce human disease. Besides, the scientific community has already foreseen swine as an attractive and alternative model to nonhuman primates for modeling human diseases due to closer anatomical, physiological and biochemical features of swine rather than rodents to humans. On this basis, we have produced the first swine ALS model by in vitro transfection of cultured somatic cells combined with somatic cell nuclear transfer (SCNT). To achieve this goal we developed a SOD1(G93A) (superoxide dismutase 1 mutated in Gly93-Ala) vector, capable of promoting a high and stable transgene expression in primary porcine adult male fibroblasts (PAF). After transfection, clonal selection and transgene expression level assessment, selected SOD1(G93A) PAF colonies were used as nuclei donors in SCNT procedures. SOD1(G93A) embryos were transferred in recipient sows, and pregnancies developed to term. A total of 5 piglets survived artificial hand raising and weaning and developed normally, reaching adulthood. Preliminary analysis revealed transgene integration and hSOD1(G93A) expression in swine tissues and 360° phenotypical characterization is ongoing. We believe that our SOD1(G93A) swine would provide an essential bridge between the fundamental work done in rodent models and the reality of treating ALS.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Animals, Genetically Modified , Disease Models, Animal , Superoxide Dismutase/genetics , Swine/genetics , Animals , Humans , Male , Superoxide Dismutase-1
14.
Vet J ; 197(2): 128-42, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23810186

ABSTRACT

Over many decades assisted reproductive technologies, including artificial insemination, embryo transfer, in vitro production (IVP) of embryos, cloning by somatic cell nuclear transfer (SCNT), and stem cell culture, have been developed with the aim of refining breeding strategies for improved production and health in animal husbandry. More recently, biomedical applications of these technologies, in particular, SCNT and stem cell culture, have been pursued in domestic mammals in order to create models for human disease and therapy. The following review focuses on presenting important aspects of pre-implantation development in cattle, pigs, horses, and dogs. Biological aspects and impact of assisted reproductive technologies including IVP, SCNT, and culture of pluripotent stem cells are also addressed.


Subject(s)
Embryo Culture Techniques/veterinary , Embryo, Mammalian/physiology , Pluripotent Stem Cells/physiology , Reproductive Techniques, Assisted/veterinary , Animals , Embryonic Development
15.
Curr Med Chem ; 19(35): 6065-71, 2012.
Article in English | MEDLINE | ID: mdl-23061626

ABSTRACT

The development of in vitro testing strategies for chemical and drug screening is a priority need in order to protect human health, to increase safety, to reduce the number of animals required for conventional testing methods and finally to meet the deadlines of current legislations. The aim of this work was to design an alternative testing method based on human embryonic stem cells for the detection of prenatal neural toxicity. For this purpose we have created a model based on the generation of neural rosettes, reproducing in vitro the gastrulation events recapitulating the formation of the neural tube in vivo. To validate the model we have exposed this complex cell system to increasing concentrations of valproic acid, a known teratogenic agent, to analyse the morphological and molecular changes induced by the toxicant. Specific assays were applied to discriminate between cytotoxicity and specific neural toxicity. Transcriptomic analysis was performed with a microarray Affimetrix platform and validated by quantitative real time RT-PCR for the expression of genes involved in early neural development, neural tube formation and neural cells migration, key biological processes in which the effect of valproic acid is most relevant. The results demonstrated that neural rosette cells respond to valproic acid exposure with molecular and morphological changes similar to those observed in vivo, indicating that this method represents a promising alternative test for the detection of human prenatal neural toxicity.


Subject(s)
Neurons/metabolism , Teratogens/metabolism , Valproic Acid/toxicity , Cell Differentiation/drug effects , Cell Line , Cell Proliferation/drug effects , Embryonic Stem Cells/cytology , Embryonic Stem Cells/drug effects , Embryonic Stem Cells/metabolism , Gene Expression Profiling , Humans , Immunohistochemistry , Neurons/pathology , Valproic Acid/chemistry
16.
Reprod Domest Anim ; 47 Suppl 3: 2-11, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22681293

ABSTRACT

Somatic cell nuclear transfer (SCNT) was first developed in livestock for the purpose of accelerating the widespread use of superior genotypes. Although many problems still exist now after fifteen years of research owing to the limited understanding of genome reprogramming, SCNT has provided a powerful tool to make copies of selected individuals in different species, to study genome pluripotency and differentiation, opening new avenues of research in regenerative medicine and representing the main route for making transgenic livestock. Besides well-established methods to deliver transgenes, recent development in enzymatic engineering to edit the genome provides more precise and reproducible tools to target-specific genomic loci especially for producing knockout animals. The interest in generating transgenic livestock lies in the agricultural and biomedical areas and it is, in most cases, at the stage of research and development, with few exceptions that are making the way into practical applications.


Subject(s)
Cloning, Organism/methods , Livestock , Nuclear Transfer Techniques/veterinary , Agriculture , Animals , Animals, Genetically Modified , Congenital Abnormalities , Genetic Engineering/methods
17.
Reproduction ; 141(5): 625-32, 2011 May.
Article in English | MEDLINE | ID: mdl-21310813

ABSTRACT

Infertility in cattle herds is a growing problem with multifactorial causes. Embryonic genotype and level of inbreeding are among the many factors that can play a role on reproductive efficiency. To investigate this issue, we produced purebred and crossbred bovine embryos by in vitro techniques from Holstein oocytes and Holstein or Brown Swiss semen and analyzed several cellular and molecular features. In the first experiment, purebred and crossbred embryos, obtained from abattoir oocytes, were analyzed for cleavage, development to morula/blastocyst stages, amino acid metabolism and gene expression of developmentally important genes. The results indicated significant differences in the percentage of compacted morulae, in the expression of three genes at the blastocyst stage (MNSOD, GP130 and FGF4) and in the utilization of serine, asparagine, methionine and tryptophan in day 6 embryos. In the second experiment, bovine oocytes were collected by ovum pick up from ten Holstein donors and fertilized with the semen of the respective Holstein sires or with Brown Swiss semen. The derived embryos were grown in vitro up to day 7, and were then transferred to synchronized recipients and recovered on day 12. We found that purebred/inbred embryos had lower blastocyst rate on days 7-8, were smaller on day 12 and had lower expression of the trophoblast gene PLAC8. Overall, these results indicate reduced and delayed development of purebred embryos compared with crossbred embryos. In conclusion, this study provides evidence that embryo genotype and high inbreeding can affect amino acid metabolism, gene expression, preimplantation development and therefore fertility in cattle.


Subject(s)
Blastocyst/metabolism , Cattle Diseases/genetics , Fertility/genetics , Gene Expression Regulation, Developmental , Inbreeding , Infertility/veterinary , Animals , Blastocyst/pathology , Cattle , Cattle Diseases/physiopathology , Chi-Square Distribution , Cytokine Receptor gp130/genetics , Embryo Culture Techniques/veterinary , Embryo Transfer/veterinary , Embryonic Development/genetics , Energy Metabolism/genetics , Female , Fertilization in Vitro/veterinary , Fibroblast Growth Factor 4/genetics , Genetic Predisposition to Disease , Gestational Age , Infertility/genetics , Infertility/physiopathology , Male , Pedigree , Phenotype , Pregnancy , Superoxide Dismutase/genetics
18.
Theriogenology ; 74(4): 557-62, 2010 Sep 01.
Article in English | MEDLINE | ID: mdl-20452007

ABSTRACT

In the pig ovary, the transition from primordial to primary and secondary ovarian follicles begins before birth, but antral follicles can be observed, for the first time, at approximately 60-90 d of age. At approximately the same time, secondary follicles become responsive to gonadotropins, leading to the formation of antral follicles. Placing pieces of ovarian tissue under the kidney capsule of immunodeficient (SCID) mice allows the requirements for follicular recruitment and development to be studied. The objective of this study was to investigate if primordial follicles contained in ovarian fragments isolated from newborn piglets (36 +/- 12 h old) and immediately transplanted under the kidney capsule of SCID mice, are able to become responsive to gonadotropins after 60 d (as in an unaltered animal). Ovarian fragments were transplanted under the kidney capsule of three groups of four female and four male SCID mice. The first group did not receive any hormonal treatment for 12 wk. The second group was treated from the 9th week with 1 IU of FSH/LH on alternating days for 3 wk, and the third group was treated with 5 IU Pregnant Mare Serum Ganadotropin (PMSG) 48 h before euthanasia. Primordial follicles contained in ovarian fragments isolated from newborn piglets developed only to the secondary stage. Therefore, development of gonadotropin responsiveness in ovarian fragments xenotransplanted in SCID mice was delayed compared to what occurs in the unaltered animal, and there was minimal response to exogenous gonadotropins.


Subject(s)
Follicle Stimulating Hormone/pharmacology , Luteinizing Hormone/pharmacology , Ovary/transplantation , Swine/growth & development , Animals , Female , Male , Mice , Mice, SCID , Ovarian Follicle/drug effects , Ovarian Follicle/growth & development , Ovarian Follicle/transplantation , Ovary/drug effects , Ovary/pathology , Transplantation, Heterologous
19.
Theriogenology ; 73(6): 748-57, 2010 Apr 01.
Article in English | MEDLINE | ID: mdl-19726075

ABSTRACT

The culture of early embryos in the surrogate xeno-oviduct was first developed in the early 1950s to allow transport of embryos at long distances. Later, it was applied to the study of culture requirements of the early embryo especially that of bovine origin. In this article, we review the data available on the culture of in vitro-matured and in vitro-fertilized embryos of Bos taurus, Sus scrofa, Equus caballus and Ovis aries in the surrogate sheep oviduct compared with data on in vitro culture in different media. Short-term and long-term cellular and molecular effects are described mainly for the bovine species where more extensive use of this technique has been made. A comparison with in vitro culture in various conditions and species indicate that embryos cultured in the sheep oviduct have close similarities to totally in vivo-derived embryos. The data provided demonstrate that the technique of in vivo culture in the surrogate sheep oviduct is versatile and allows a high rate of embryonic development in all species examined.


Subject(s)
Cattle/embryology , Embryo Culture Techniques/veterinary , Fallopian Tubes , Horses/embryology , Sheep/embryology , Swine/embryology , Animals , Embryo Culture Techniques/methods , Embryonic Development , Female , Fertilization in Vitro/veterinary
20.
Reprod Domest Anim ; 43 Suppl 2: 1-7, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18638099

ABSTRACT

This paper summarizes the major advances in farm animal assisted reproduction in the last 20 years with particular attention to the contributions of the authors. A main emphasis is on the biology of the oocyte, including a description of methods for isolation of developing follicles and culture of the corresponding oocytes. Milestones that have led to optimization of procedures for maturation of fully grown oocytes, fertilization, intracytoplasmic sperm injection and embryo culture in sheep, cattle, pigs and horses are described. The current status of nuclear transfer, cloning and embryonic stem cell generation and culture is also summarized for all major farm animal species. It is concluded that the manipulation of early development in farm animals is of crucial importance for agricultural purposes and that reproductive biotechnologies in farm animals are expected to play an increasing role in the next decades due to the growing demand for agricultural products from the emerging economies worldwide. In the biomedical field large animals represent increasingly important research models especially in the stem cell field for creating genetically modified animals for specific purposes. Finally, the successful translation of large animal research in the applied context requires solid science, long-term resource commitment from involved institutions, and vision, dedication and entrepreneurial skills from the scientists involved.


Subject(s)
Breeding , Embryo, Mammalian/physiology , Oocytes/growth & development , Pregnancy, Animal/physiology , Reproductive Techniques, Assisted/veterinary , Animals , Cattle , Cryopreservation/veterinary , Female , Horses , Male , Nuclear Transfer Techniques/veterinary , Oocytes/physiology , Ovarian Follicle/growth & development , Ovarian Follicle/physiology , Pregnancy , Sperm Injections, Intracytoplasmic/methods , Sperm Injections, Intracytoplasmic/veterinary
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