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Denguin, France

Gamarra G.,UNCEIA Departement Recherche et Developpement | Ponsart C.,UNCEIA Departement Recherche et Developpement | Lacaze S.,MIDATEST | Le Guienne B.,UNCEIA Departement Recherche et Developpement | And 7 more authors.
Reproduction, Fertility and Development | Year: 2015

Rapid genetic improvement in cattle requires the production of high numbers of embryos of excellent quality. Increasing circulating insulin and/or glucose concentrations improves ovarian follicular growth, which may improve the response to superovulation. The measurement of anti-Müllerian hormone (AMH) can help predict an animal's response to superovulation treatment. The aim of the present study was to investigate whether increasing circulating insulin concentrations, through propylene glycol (PG) drenches, could improve in vitro embryo production in oestrus-synchronised superovulated heifers with different AMH profiles. Holstein heifers were grouped according to pre-experimental AMH concentrations as low (L) or high (H). The PG drench increased circulating insulin and glucose concentrations and reduced β-hydroxybutyrate and urea concentrations compared with the control group. AMH was a good predictor of follicle and oocyte numbers at ovum pick-up (OPU), and of oocyte and embryo quality (AMH H>AMH L). PG in the AMH H group increased the number of follicles and blastocyst quality above that in the control group, but did not improve these parameters in the AMH L group. These results indicate that short-term oral PG supplementation modifies an animal's metabolic milieu and is effective in improving in vitro embryo production, after superovulation-OPU, more markedly in heifers with high rather than low AMH concentrations. © 2015 CSIRO. Source


Gamarra G.,UNCEIA Departement Recherche et Developpement | Ponsart C.,UNCEIA Departement Recherche et Developpement | Lacaze S.,MIDATEST | Le Guienne B.,UNCEIA Departement Recherche et Developpement | And 6 more authors.
Livestock Science | Year: 2014

This study was designed to determine the effects of dietary propylene glycol (PG; Propypact®, DIFAGRI, France) on blood metabolites, metabolic and reproductive hormones and follicular growth in 10 dairy heifers. Treatments consisted of (1) 1.1kg of sugar beet pulp (Control), (2) 150g PG (PG150) and (3) 300g PG (PG300). Each heifer received the three treatments in different randomized orders. A standard hay/concentrate diet, formulated to allow a daily liveweight gain of 900g/day, was given at 8:00 and the dietary treatments were given at 16:00 from Days 1 to 13 of the oestrous cycle following induced oestrus (Day 0). Oestrus induction treatment consisted of a subcutaneous 3mg norgestomet implant inserted for 9 days combined with GnRH treatment (i.m.) at implant insertion. Two days before implant removal, 500μg cloprostenol was administered i.m. Blood samples were collected by jugular venipuncture every 2h for 24h on Days 0 and 13 to measure plasma insulin, glucose, β-hydroxybutyrate (BHB) and urea concentrations. Blood samples were also collected to measure insulin-like growth factor-1 (IGF-1), oestradiol, progesterone concentrations on Days 2, 6, 9 and 12 and AMH (Anti-Müllerian hormone) on Days 0, 2, 6, 9 and 12. On Days 2, 6, 9 and 12 ovarian follicular growth was evaluated; the total number of follicles and their diameters were recorded and classed (2-3mm, 4-7mm, and >8mm). Results were analysed by repeated-measures ANOVA. There were no treatment, day and interaction effects on average urea concentrations while there were some differences between Days 0 and 13 for insulin, glucose and BHB. Insulin and glucose concentrations were higher on Day 13 compared to Day 0 and the opposite was observed for BHB. There were treatment, time and interaction effects on glucose and BHB concentrations measured over 24h on Day 13; glucose concentrations were higher (P<0.05) at 4:00, 8:00, 12:00, 16:00 and 20:00h, whereas BHB concentrations were lower (P<0.05) at 20:00 and 22:00h in the PG300 group compared to the control and PG150 groups. There were treatment, day and interaction effects on IGF-1 and progesterone concentrations, and the number of small follicles. PG150 resulted in higher progesterone concentrations on Days 9 and 12, and more small follicles on Day 2 compared to Control. AMH concentrations were unaffected by day of oestrous cycle and dietary treatment. However a negative correlation was observed between pre-PG distribution insulin and AMH (r=-0.47, P<0.05). These results indicate that short-term dietary PG supplementation affects circulating concentrations of metabolites and metabolic hormones, increases progesterone concentrations and the number of small follicles. Propylene glycol supplementation may be effective in improving oocyte production when combined with hormonal treatments to stimulate follicular growth for superovulation or ovum-pick up. © 2014 Elsevier B.V. Source


Ponsart C.,Animal Health Laboratory | Gamarra G.,Animal Health Laboratory | Lacaze S.,MIDATEST | Ponter A.A.,National Veterinary School of Alfort | Ponter A.A.,CNRS Developmental Biology Laboratory
Animal Reproduction | Year: 2014

Nutritional and metabolic status of domestic ruminant females is linked with reproductive success. Diet can influence ovarian activity via effects at various levels of the hypothalamus-pituitary-ovarian axis. Changes in the plane of nutrition can affect follicular growth by inducing changes in plasma metabolites and metabolic hormones, such as insulin and IGF1. This paper will review different results from in vivo and in vitro feeding approaches describing a programmed sequence in circulating insulin concentrations. The stimulatory effect of insulin and IGF1 on follicle growth has been previously demonstrated, especially on small follicle growth prior to superovulation. Thus, in vivo feeding strategies have been recently tested to enhance embryo development. It has been shown that the interaction between the gonadotropin content of the superstimulatory preparation with the nutritional program of the donor cow needs to be considered when aiming to optimize the success of ovarian superstimulatory protocols. Moreover, some practical feeding strategies such as short term dietary propylene glycol could improve in vitro embryo production in superovulated growth-restricted heifers. To conclude, different diets or dietary supplements may improve fertility and embryo quality by inducing a programmed sequence in circulating insulin concentrations. Source


Capitan A.,UNCEIA Union Nationale des Cooperatives dElevage et dInsemination Animale | Capitan A.,French National Institute for Agricultural Research | Michot P.,UNCEIA Union Nationale des Cooperatives dElevage et dInsemination Animale | Michot P.,French National Institute for Agricultural Research | And 15 more authors.
Reproduction, Fertility and Development | Year: 2015

Fertility is a major concern in the dairy cattle industry and has been the subject of numerous studies over the past 20 years. Surprisingly, most of these studies focused on rough female phenotypes and, despite their important role in reproductive success, male- and embryo-related traits have been poorly investigated. In recent years, the rapid and important evolution of technologies in genetic research has led to the development of genomic selection. The generalisation of this method in combination with the achievements of the AI industry have led to the constitution of large databases of genotyping and sequencing data, as well as refined phenotypes and pedigree records. These resources offer unprecedented opportunities in terms of fundamental and applied research. Here we present five such examples with a focus on reproduction-related traits: (1) detection of quantitative trait loci (QTL) for male fertility and semen quality traits; (2) detection of QTL for refined phenotypes associated with female fertility; (3) identification of recessive embryonic lethal mutations by depletion of homozygous haplotypes; (4) identification of recessive embryonic lethal mutations by mining whole-genome sequencing data; and (5) the contribution of high-density single nucleotide polymorphism chips, whole-genome sequencing and imputation to increasing the power of QTL detection methods and to the identification of causal variants. © IETS 2015. Source


Ponsart C.,UNCEIA Research and Development | Le Bourhis D.,UNCEIA Research and Development | Knijn H.,Crv Inc. | Fritz S.,French National Institute for Agricultural Research | And 7 more authors.
Reproduction, Fertility and Development | Year: 2014

Genomic tools are now available for most livestock species and are used routinely for genomic selection (GS) in cattle. One of the most important developments resulting from the introduction of genomic testing for dairy cattle is the application of reasonably priced low-density single nucleotide polymorphism technology in the selection of females. In this context, combining genome testing and reproductive biotechnologies in young heifers enables new strategies to generate replacement and elite females in a given period of time. Moreover, multiple markers have been detected in biopsies of preimplantation stage embryos, thus paving the way to develop new strategies based on preimplantation diagnosis and the genetic screening of embryos. Based on recent advances in GS, the present review focuses on new possibilities inherent in reproductive technologies used for commercial purposes and in genetic schemes, possible side effects and beneficial impacts on reproductive efficiency. A particular focus is on the different steps allowing embryo genotyping, including embryo micromanipulation, DNA production and quality assessment. © IETS 2014. Source

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