Papers by Ricardo Alberio
Reproduction, Fertility and Development, 2005
Until now, the major obstacle associated with the extensive use of in vitro-produced bovine embry... more Until now, the major obstacle associated with the extensive use of in vitro-produced bovine embryos is the lack of suitable methods to cryopreserve them. At least two approaches exist for overcoming this problem. One is to adjust cryopreservation methods to the requirements of these embryos, and the other is to improve embryo quality by using an appropriate in vitro environment for embryo production. The objective of this study was to determine the effect of estrous cow serum (ECS) during in vitro culture on embryo survival after cryopreservation by slow freezing or vitrification. Cumulus-oocytes complexes were in vitro-matured and fertilized as previously described (Ferre et al. 2003 Theriogenology 59, 301 abst). Presumptive zygotes were denuded from cumulus cells and cultured in groups of 50 in 400 μL drops of CR1aa medium. Seventy-two hour post-insemination (PI) embryos were randomly separated into three groups. Each group was then cultured in CR1aa + 5% ECS (without BSA; CR1-ECS...
El objetivo de este trabajo fue determinar el efecto de la sincronizacion del servicio sobre la p... more El objetivo de este trabajo fue determinar el efecto de la sincronizacion del servicio sobre la productividad estimada (kg de ternero destetado/vaca tratada) en siete rodeos de vacas A. Angus multiparas. Las vacas fueron asignadas a la sincronizacion de la inseminacion mediante un tratamiento con progesterona y estradiol (Sincronizacion, n=593) o a la no sincronizacion (Control, n= 385). En Sincronizacion se hizo inseminacion artificial sistematica (IAS); la temporada de servicio duro 30 dias. La productividad del rodeo se estimo asumiendo que la gestacion duro 280 dias, que los terneros pesaron 23 kg al nacer y que ganaron 0,687 kg/dia, siendo destetados a los 180 dias de iniciada la paricion en cada rodeo. La prenez obtenida mediante la IAS fue de 33±9,5%. La tasa de concepcion del primer celo (vacas control prenadas en el primer celo/vacas control inseminadas) fue 52,1±13,8%. La Sincronizacion produjo efectos significativos respecto del Control (p 0,05). La tasa de concepcion ...
Small Ruminant Research, 2010
The objective of this study was to characterize the vaginal bacterial flora and subsequent pregna... more The objective of this study was to characterize the vaginal bacterial flora and subsequent pregnancy rates after AI in sheep subjected to 4 different estrous synchronization regimes – the use of two intravaginal devices (silicone or polyurethane sponges), and two different treatment periods (7 or 14 days). Twenty-one multiparous Texel ewes were randomly allocated to 4 treatment groups during the
The results of the combination of sex-sorted sperm and superovulation (SOV) have not been very en... more The results of the combination of sex-sorted sperm and superovulation (SOV) have not been very encouraging so far, due to the low quantity of sperms as well as their short life. In a previous study conducted in Brazil in Holstein cows, it was shown that using the protocol of SOV P36/Lh60 and inseminating with sex-sorted sperm at the 18 and 30 hours (interval of 12h between the two inseminations) after application of the inductor of the ovulationit is obtained an equal quantity of transferable structures than inseminating at the 12 and 24h with non-sorted sperm. The aim of this investigation was to adjust the hours of the artificial insemination (AI) in superovulated and inseminated cows with sex-sorted sperm to achieve better synchrony with ovulations, so in this way to increase the quantity of transferable embryosobtained. This adjustment evaluated 2 moments of AI in which the interval between both diminished to 6h. For this, 30 lactating Holstein cows previously superovulated once...
Reproduction, Fertility and Development
Recipient handling during embryo transfer (ET) induces prostaglandin F2α (PGF2α) production in 2 ... more Recipient handling during embryo transfer (ET) induces prostaglandin F2α (PGF2α) production in 2 periods: an early transient and rapid increase around the time of ET, followed by another 2 to 4 h later. This PGF2α is associated with embryonic loss during early gestation by affecting both the embryo and the corpus luteum. To control this, antiprostaglandins such as flunixin meglumine (FM) have been applied IM at the time of ET with varying results. In such studies, the interaction of IM administration of FM and difficulty of transfer has not always been evaluated, possibly confusing the interpretation of the results. Furthermore, IV FM injection at ET and its relationship with pregnancy rates (PR) has not been determined. The objectives were (1) to determine the relationship between difficulty of ET and PR; and (2) to evaluate the efficacy of IM v. IV FM on pregnancy outcomes. One hundred and ten crossbred (Bos taurus × Bos indicus) heifers (18-24 months old) from 3 farms were used a...
Reproduction, Fertility and …, 2003
Ultrasonography is widely used in domestic species of camelids, but there is no information about... more Ultrasonography is widely used in domestic species of camelids, but there is no information about the use of this technique for pregnancy diagnosis and determination of embryonic or fetal losses in the vicuña (Vicugna vicugna). The study was performed in 202 vicuñas (3-year-old females, n = 31; adult females, n = 171) mated during the summer months (January through March 2001) at the Abra Pampa Experimental Farm of Altitude in north-west Argentina. Transrectal ultrasound examination was performed in May (estimated 40–120 days of gestation) to determine the number of pregnant females. The pregnancy rate was 45.5% (92/202). No significant difference (P > 0.05) was observed between the pregnancy rate of 3-year-old females (41.9%) and adult females (46.2%). In December (estimated 250–330 days of gestation) of the same year, a second ultrasonographic study was performed on those vicuñas that were diagnosed as pregnant from the first ultrasound scan. Of 92 animals diagnosed as pregnant in May, only 84 were present in December, because eight females died in the period of study. Overall, 11.9% (10/84) of fetuses were lost during the period (18.1% in 3-year-old vicuñas and 10.9% in adult vicuñas). In conclusion, transrectal ultrasonography was found to provide a rapid and non-invasive means for pregnancy and fetal mortality diagnosis in vicuñas.
Theriogenology, 2011
Whole seminal plasma (SP) enhances the function and fertility of frozen/thawed ram sperm. The obj... more Whole seminal plasma (SP) enhances the function and fertility of frozen/thawed ram sperm. The objective of the current study was to investigate whether SP proteins capable of binding to molecules from the sperm plasma membrane were conserved among ram breeds, and whether these proteins were sufficient to overcome cryopreservation-induced reductions in sperm quality. Whole ram SP, obtained from rams of various breeds, improved progressive motility of frozen/thawed sperm at all times evaluated (P
Theriogenology, 2006
The present study investigated the effect of estrous cow serum (ECS) during culture of bovine emb... more The present study investigated the effect of estrous cow serum (ECS) during culture of bovine embryos on blastocyst development and survival after cryopreservation by slow freezing or vitrification. Embryos were derived from in vitro maturation (IVM) and in vitro fertilization (IVF) of abbatoir-derived oocytes. At Day 3, embryos were cultured in three different media: Charles Ronsenkrans medium + amino acids (CR1aa; without bovine serum albumin (BSA)) + 5% estrous cow serum (CR1-ECS), CR1aa + 3 mg/mL BSA (CR1-BSA) or CR1aa + 5% ECS + 3 mg/ mL BSA (CR1-ECS-BSA). At 7.5 d post-insemination (PI), blastocyst yield and quality were evaluated; blastocysts and expanded blastocysts from each media were cryopreserved by Open Pulled Straw (OPS) vitrification method or slow freezing (1.5 M ethylene glycol, EM). Total blastocyst yield did not differ among CR1-ECS, CR1-BSA and CR1-ECS-BSA (30.9, 33.1 and 32.9%, respectively, P < 0.05). Embryo survival (hatching rate) was higher in vitrified versus slow-frozen embryos (43% versus 12%, respectively, P < 0.01), and in embryos cultured in CR1-BSA (40.3%) compared with those cultured in serum-containing media (CR1-ECS, 21.5% and CR1-ECS-BSA, 19.8%; P < 0.01). In conclusion: (a) it was possible to produce in vitro bovine embryos in serum-free culture medium without affecting blastocyst yield and quality; (b) serum-free medium produced the best quality www.journals.elsevierhealth.com/periodicals/the Theriogenology 65 (2006) 1551-1562
Tropical Animal Health and Production
BMC Developmental Biology
Background: The segregation of the hypoblast and the emergence of the pluripotent epiblast mark t... more Background: The segregation of the hypoblast and the emergence of the pluripotent epiblast mark the final stages of blastocyst formation in mammalian embryos. In bovine embryos the formation of the hypoblast has been partially studied, and evidence shows that MEK signalling plays a limited role in the segregation of this lineage. Here we explored the role of different signalling pathways during lineage segregation in the bovine embryo using immunofluorescence analysis of NANOG and SOX17 as readouts of epiblast and hypoblast, respectively. Results: We show that SOX17 starts to be expressed in 16-32-cell stage embryos, whereas NANOG is first detected from 8-cell stage. SOX17 is first co-expressed with NANOG, but these markers become mutually exclusive by the late blastocyst stage. By assessing the expression kinetics of NANOG/SOX17 we show that inhibition of MEK signalling can eliminate SOX17 expression in bovine blastocysts, without altering NANOG expression. Modulation of WNT, PKC and LIF did not affect NANOG expression in the epiblast when used in combination with the ERK inhibitor. Conclusions: This study shows that SOX17 can be used as a reliable early marker of hypoblast in the bovine, and based on its expression profile we show that the hypoblast segregates in day 7 blastocysts. Furthermore, SOX17 expression is abolished using 1 μM of PD0325901, without affecting the NANOG population in the epiblast. Modulation of WNT, PKC and LIF are not sufficient to support enhanced NANOG expression in the epiblast when combined with ERK inhibitor, indicating that additional signalling pathways should be examined to determine their potential roles in epiblast expansion.
BMC research notes, Jan 27, 2018
The use of induced pluripotent stem (iPS) cells as an alternative to embryonic stem cells to prod... more The use of induced pluripotent stem (iPS) cells as an alternative to embryonic stem cells to produce transgenic animals requires the development of a biotechnological platform for their generation. In this study, different strategies for the generation of bovine and porcine iPS cells were evaluated. Lentiviral vectors were used to deliver human factors OCT4, SOX2, KLF4 and c-MYC (OKSM) into bovine and porcine embryonic fibroblasts and different culture conditions were evaluated. Protocols based on the integrative lentiviral vector STEMCCA produced porcine iPS-like cells more efficiently than in bovine cells. The iPS-like cells generated displayed stem cell features; however, expression of exogenous factors was maintained along at least 12 passages. Since inactivation of the exogenous factors is still a major bottleneck for establishing fully reprogrammed iPS cells, defining culture conditions that support endogenous OKSM expression is critical for the efficient generation of farm an...
Small Ruminant Research, 2015
To determine the differences in the physio-logical processes that affect the postpartum reproduct... more To determine the differences in the physio-logical processes that affect the postpartum reproductive performance, follicular dynamics, postpartum cyclicity resumption and suckling behavior were studied in cows of breeds with enhanced reproductive performance (Angus) and poor reproductive performance (Criolla Argentina) in two experiments. In experiment 1, ovarian follicular dynamics was monitored daily by transvaginal ultrasonography in 6 suckled Angus cows and 6 suckled Criolla Argentina cows, from day 30 postpartum to either 90 days after calving or when the second ovulation was detected whichever came earlier. Simultaneously suckling behavior was observed daily for 6 hours at 18 stages of lactation. In each observation, the frequency (number of suckling bouts), average duration of each bout (minutes) and total time spent in suckling (minutes/6 hours), were recorded. In experiment 2, the return to cyclicity was monitored weekly by transrectal ultrasonography in 20 suckled Angus co...
La productividad de un rebaño de cría depende de su eficiencia reproductiva y ésta, en parte, dep... more La productividad de un rebaño de cría depende de su eficiencia reproductiva y ésta, en parte, depende del intervalo parto-reiniciode la actividad estral. Un método que permita que las vacas muestren celo y conciban en el primer periodo de la época de servicio mejorará la tasa de preñez y permitirá concentrar los partos al principio de la paridera. Además, estas vacas destetarán terneros más pesados y tendrán una mejor eficacia reproductiva que aquellas que paren más tarde. Se utilizaron 76 vacas de cría con el objetivo de evaluar la respuesta estral y ovárica producidas por un destete temporal (DT) de 80 h de duración asociado a una inyección de benzoato de estradiol (BE) 32 h antes del retorno de los terneros y del DT o BE utilizados en forma separada . Los animales en condiciones de pastoreo fueron agrupados según su condición corporal y fecha de parto y distribuidos aleatoriamente a los siguiente grupos: Control -C-: 20; DT: 19; BE: 19; DT+BE: 18. El estado de aciclia fue determi...
Volver a: Ecografía y ultrasonido RESUMEN El diagnóstico de gestación por medio de ultrasonografí... more Volver a: Ecografía y ultrasonido RESUMEN El diagnóstico de gestación por medio de ultrasonografía es ampliamente utilizado en las especies domésticas. No existe información sobre el uso de esta técnica en vicuñas (Vicugna vicugna). Este trabajo se realizó en el Campo Experimental de Altura (CEA INTA Abra Pampa, Jujuy, Argentina) ubicado a 3.484 m.s.n.m. Los objetivos del presente trabajo fueron determinar la factibilidad de realizar el diagnóstico de gestación por medio de ultrasonografía y establecer el porcentaje de preñez en un rebaño de vicuñas mantenidas en semicautiverio. Se realizó el diagnóstico en 202 vicuñas. El porcentaje de preñez fue del 50,0%. No se observaron diferencias significativas (p>0,05) entre la tasa de gestación en hembras de 3 años (57,6%) y hembras adultas (48,5%) ni entre la tasa de gestación de hembras en lactancia (50,0%) y hembras sin cría al pie (49,1%). Se concluye que el uso de la ultrasonografía para diagnóstico de gestación en vicuñas es una té...
Reproduction in domestic animals = Zuchthygiene, Jan 15, 2015
We have already shown that seminal collection method affects seminal plasma composition and sperm... more We have already shown that seminal collection method affects seminal plasma composition and sperm quality in Corriedale rams. In this study, we evaluated the effect of seminal plasma collected by electroejaculation or artificial vagina on sperm resistance to cryodamage. Seminal plasma of five rams of the Corriedale breed collected by artificial vagina or electroejaculation was added before freezing to sperm cells collected by the two methods, and post-thaw quality parameters were evaluated. We found that seminal plasma has no effect on sperm resistance to cryodamage. However, we observed significantly higher percentages of sperm with intact and functional plasma membrane, intact acrosome and greater fertilizing potential after thawing in samples obtained by electroejaculation. This study demonstrates that sperm collected by electroejaculation are more resistant to damage caused by cryopreservation than those collected by artificial vagina.
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Papers by Ricardo Alberio