The effect of melatonin and season on in vivo embryo production of Dohne Merino ewes

Buffoni, A.; Vozzi, Pedro Alejandro; González, Díaz; Rios, G.; Viegas-Bordeira, H.; Abecia, J. A.

doi:10.1016/j.smallrumres.2014.05.003

Cited by 9 publications

(7 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These two situations can be solved when LAI is performed twice with the interval of 6 hr, which coincides with the median time from first to last ovulation reported in superovulated sheep(Cognié, Baril, Poulin, & Mermillod, ). The use of two LAI produces good results in multiple ovulated sheep fertilized with either fresh and frozen semen (respecting inclusion criteria), similar results were reported by Lima et al () and Buffoni et al ().…”

Section: Discussionsupporting

confidence: 84%

Effect of semen and donor factors on multiple ovulation and embryo transfer (MOET) in sheep

Bergstein-Galan¹,

Weiss

Kozicki

2018

Reprod Domestic Animals

View full text Add to dashboard Cite

Contents Multiple ovulation and embryo transfer (MOET) is an important tool in the sheep industry for increasing numbers of genetically superior individuals. The objective of this study was to evaluate the effect of semen source (frozen or fresh), the number of embryo collection procedures for each donor (NECP), the season in which embryo transfer and collection was performed, and the age and breed of the donor, on the number of recovered embryos and pregnancy rates after embryo transfer. The Alamos Genetics’ flushing station database was used. This consisted of 140 embryo collection procedures, from 53 Dorper and White Dorper sheep donors, aged between one and eight years, totalling 1,200 collected embryos. Neither the number of retrieved embryos nor the pregnancy rate was affected by the semen preservation method (fresh or frozen), NECP or the age and breed of donor. The season did not affect the number of collected embryos but had a significant effect (p < 0.05) on the recipient pregnancy rate, with higher pregnancy rates reported in the winter (65.57% ± 25.33%) compared with spring (37.11% ± 33.27%), summer (29.95% ± 28.33%) or autumn (35.03% ± 31.66%). There is an estimated increase of 98.4% and 71.5% of embryos recovered in the spring and summer seasons, respectively, when winter is used as reference. The survival of embryos is significantly higher when implanted during the breeding season, more specifically in winter. Embryo collection can be carried out throughout the year in sheep, but there may be a marginal advantage in the use of superovulation and fresh embryo transfer programmes in the autumn and winter.

show abstract

Section: Discussionsupporting

confidence: 84%

Effect of semen and donor factors on multiple ovulation and embryo transfer (MOET) in sheep

Bergstein-Galan¹,

Weiss

Kozicki

2018

Reprod Domestic Animals

View full text Add to dashboard Cite

show abstract

“…McEvoy et al (1998) were the first to experiment with superovulated ewes during the anoestrous period to increase their embryo production but found no difference in the number and quality of embryos between melatonin-treated and untreated ewes. Similar results were reported by other researchers (Buffoni et al, 2014;Abecia et al, 2019), who used external melatonin to improve embryo production in multiple ovulation and embryo transfer (MOET) programmes, outside the breeding season as well. In contrast, Mitchell et al (2002) found no effect of melatonin supplementation on ovulation, fertilisation or viability rates, nor on the number of viable embryos per ewe; however, the number of degenerate embryos in the anoestrous period was highest in the melatonin-treated group, probably due to seasonal shifts in LH secretion and/or its effect on follicular function.…”

Section: Embryo Productionsupporting

confidence: 89%

Various approaches to influence melatonin level in sheep reproduction

et al. 2023

View full text Add to dashboard Cite

A new field of research in reproductive biology was heralded by the discovery of melatonin in 1958. The concentration of melatonin follows light-dark cycles with significantly higher concentrations during darkness. The authors present the importance of the melatonin protein hormone by focusing on the reproductive processes in domestic sheep. In their literature review, they report that sheep melatonin levels show daily and seasonal rhythms. In sheep as a seasonal breeder and short-day animal species, seasonal increases in melatonin production stimulate sexual activity. The authors describe innovative possibilities for regulating melatonin levels in sheep production. The use of exogenous melatonin brings forward the expression of the sexual cycle. It increases the fertility rate, the number of lambs born, and the chances of survival of twin lambs. Melatonin is a neuroprotection compound against cerebral hypoxia and the development of inflammatory processes in the growing foetus and the newborn lamb.

show abstract

“…tonin improves developmental oocyte competence in the seasonal anestrus period (Vázquez et al, 2010) and significantly increases the maturation rate of oocytes and tends to increase their cleavage rate (Casao et al, 2010). Also, melatonin reduces embryo degeneration (Buffoni et al, 2014) and increases the percentage of hatched blastocysts (Abecia et al, 2002) during seasonal anestrus. Furthermore, the luteotrophic effect of melatonin has been reported (Durotoye et al, 1997), leading to an increase in plasma P 4 concentrations.…”

mentioning

confidence: 99%

Manipulation of reproductive seasonality using melatonin implantation in Anglo-Nubian does treated with controlled internal drug release and equine chorionic gonadotropin during the nonbreeding season

El-Mokadem

El-Din

Ramadan

et al. 2017

Journal of Dairy Science

View full text Add to dashboard Cite

The objective of this study was to compare the efficiency of hormonal treatments on ovarian activity and reproductive performance in anestrous Anglo-Nubian does during the nonbreeding season (February to May). A total of 48 multiparous does were divided into 2 groups (24 lactating does and 24 dry does). In each group, animals were allocated randomly into 2 equal subgroups (12 does each). In the first subgroup, does received a single 18-mg melatonin implant for 42 d followed by a controlled internal drug release (CIDR) device for 19 d in conjunction with 500 IU of equine chorionic gonadotropin (eCG) i.m. on the day of CIDR device removal. The second subgroup received CIDR combined with eCG in parallel with the first subgroup. Melatonin implantation induced a luteotrophic effect, expressed as an increasing number of corpora lutea, increased serum progesterone concentration, and reduced estradiol concentration. Regardless of treatment, dry does showed greater value of progesterone concentration. With the advancement of day of treatment, number of total follicles, small follicles, and medium follicles tended to increase to the greatest values at the day of CIDR device insertion. Furthermore, at day of mating, the numbers of large follicles reached the greatest value, which was associated with the lowest value of the number of corpora lutea. At day of mating, serum progesterone concentration achieved the lowest value, which increased until d 56 of pregnancy. The estradiol:progesterone ratio showed the opposite trend. The detrimental effect of reproductive seasonality, expressed as cessation of estrus behavior and fertile mating during the nonbreeding season, was successfully alleviated by the CIDR-eCG protocol. Furthermore, melatonin implantation in conjunction with the CIDR-eCG protocol enhanced conception rate and fecundity at d 28 of pregnancy and prolificacy at d 56 of pregnancy compared with does that were not implanted. Interestingly, does that failed to conceive did not come to heat again. In conclusion, the beneficial effect of melatonin implantation in conjunction with the CIDR-eCG protocol on the luteotrophic effect was reflected in the increasing number of corpora lutea, increasing progesterone concentration, and decreasing estradiol concentration. Furthermore, conception rate, prolificacy, and fecundity were improved compared with does that were not implanted during the nonbreeding season.

show abstract

The effect of melatonin and season on in vivo embryo production of Dohne Merino ewes

Cited by 9 publications

References 16 publications

Effect of semen and donor factors on multiple ovulation and embryo transfer (MOET) in sheep

Effect of semen and donor factors on multiple ovulation and embryo transfer (MOET) in sheep

Various approaches to influence melatonin level in sheep reproduction

Manipulation of reproductive seasonality using melatonin implantation in Anglo-Nubian does treated with controlled internal drug release and equine chorionic gonadotropin during the nonbreeding season

Contact Info

Product

Resources

About