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Bianchi C.P.,CONICET | Meikle A.,University of Montevideo | Benavente M.A.,CONICET | Alvarez M.A.,National University of Central Buenos Aires | And 4 more authors.
Reproduction in Domestic Animals | Year: 2015

Endometrial expression of oestrogen receptor-α (ERα), progesterone receptor (PR) and cyclooxigenase-2 (COX-2) was evaluated in non-pregnant and pregnant llamas during the period when luteolysis/maternal recognition of pregnancy is expected to occur. Females (n = 28) were divided into two groups: non-pregnant llamas were induced to ovulate with a Buserelin injection, and endometrial biopsies were obtained on day 8 (n = 5) or 12 (n = 5) post-induction of ovulation. Animals of the pregnant group (n = 18) were mated with a fertile male. Pregnancy was confirmed by the visualization of the embryo collected by transcervical flushing in 5 of 9 animals on day 8 post-mating and by progesterone profile on day 12 post-mating in 4 of 9 animals, when endometrial biopsies were obtained. An immunohistochemical technique was used to evaluate receptors population and COX-2 expression. Pregnant llamas showed a higher percentage of positive cells and stronger intensity for ERα than for non-pregnant llamas in stroma on day 8 and in the luminal epithelium on day 12 post-induction of ovulation, while a deep decrease in endometrial PR population was reported in pregnant llamas on that day in luminal and glandular epithelia and stroma. In the luminal epithelium, COX-2 expression was lower in pregnant than in non-pregnant animals. Briefly, the increase of ERα in pregnant llamas gives further support to the hypothesis that oestrogens are involved in the mechanism of maternal recognition of pregnancy. Endometrial PR decrease in pregnant llamas might be a necessary event to allow the expression of proteins involved in conceptus attachment, a mechanism widely accepted in other species. Moreover, embryo seems to attenuate maternal PGF2α secretion during early pregnancy by decreasing the endometrial expression of COX-2 in the luminal epithelium of pregnant llamas. © 2015 Blackwell Verlag GmbH. Source


Trasorras V.,Catedra de Teriogenologia | Giuliano S.,Catedra de Teriogenologia | Giuliano S.,Institute Investigacion y Tecnologia en Reproduccion Animal INITRA | Chaves G.,Catedra de Teriogenologia | And 9 more authors.
Reproduction in Domestic Animals | Year: 2012

Contents: The aim of this study was to carry out in vitro fertilization using spermatozoa selected with Androcoll-E™ and to evaluate the efficiency of the culture medium DMEM-F12 for in vitro embryo development in the llama. Twelve adult females from 18 superstimulated (67%) were used as oocyte donors. They were superstimulated with 1500IU of eCG and after 5days, received a single dose of buserelin. Twenty hours post-injection, follicular aspiration was conducted by flank laparotomy. Semen collections were performed under general anesthesia by electroejaculation of the male. The ejaculates were processed with a solution of collagenase (0.1%) and an Androcoll-E™ column was used to improve the sample. Sixty nine COCs were recovered from 79 aspirated follicles (87% recovery). Only expanded COCs were used (n=67); they were randomly placed in groups of 1-5 in Fertil-TALP and the sperm suspension (20×10 6 live spermatozoa/ml) was added to each fertilization microdroplet. After 24h, they were randomly placed in one of two culture media: SOF (n=34) or DMEM-F12 (n=33) and incubated for 6days in humidified atmosphere of 5% CO 2, 5% O 2 and 90% N 2 at 38°C. The blastocyst rate was 20% (7/34) in SOF medium (3 hatched, 2 expanded and 2 early blastocysts) and 15% (5/33) in DMEM medium (all expanded blastocysts). In conclusion, using Androcoll-E™ it is possible to select good quality spermatozoa from llama ejaculates for in vitro fertilization and to produce blastocysts in DMEM-F12 medium. This is also the first time that hatched llama blastocysts have been produced after culture in a defined medium such as SOFaa. © 2011 Blackwell Verlag GmbH. Source


Trasorras V.,Institute Investigacion y Tecnologia en Reproduccion Animal INITRA | Baca Castex C.,Institute Investigacion y Tecnologia en Reproduccion Animal INITRA | Alonso A.,Institute Investigacion y Tecnologia en Reproduccion Animal INITRA | Giuliano S.,Institute Investigacion y Tecnologia en Reproduccion Animal INITRA | And 7 more authors.
Animal Reproduction Science | Year: 2014

The aim of this study was to evaluate the developmental competence and pregnancy rate of llama hatched blastocysts produced in vitro using gametes from live animals and two different culture conditions. Fifteen adult females were superstimulated with 1500IU of eCG, eleven (73%) responded to the treatment and were used as oocyte donors. Follicular aspiration was conducted by flank laparotomy. Semen collections were performed under general anesthesia by electroejaculation of the male. Sixty-six COCs were recovered from 77 aspirated follicles (86% recovery) and were randomly placed in Fertil-TALP microdroplets with the sperm suspension (20×106live spermatozoa/ml). After 24h, they were placed in SOFaa medium supplemented with FCS and randomly assigned to one of two culture conditions. Culture condition 1 (CC1) consisted of 6 days of culture (n=28) and culture condition 2 (CC2) consisted of renewing the culture medium every 48h (n=35). In CC1, the blastocyst rate was 36% (10/28) and the hatched blastocyst rate was 28% (8/28) whereas in CC2, the blastocyst rate was 34% (12/35) and the hatched blastocyst rate was 20% (7/35) (p>0.05). No pregnancies were obtained after embryo transfer (ET) of CC1 blastocysts (0/8) while one pregnancy was obtained (1/7) after transferring a hatched blastocyst from CC2. Forty-two days after the ET, the pregnancy was lost.This study represents the first report of a pregnancy in the llama after intrauterine transfer of embryos produced by in vitro fertilization using gametes from live animals. © 2014 Elsevier B.V. Source

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