Effect of the interval between estrus onset and artificial insemination on sex ratio and fertility in cattle: a field study

Martínez, Félix; Kaabi, M.; Martínez‐Pastor, Felipe; Álvarez, M.; Anel, E.; Boixo, J.C.; Paz, P. de; Anel, L.

doi:10.1016/j.theriogenology.2004.01.002

Cited by 46 publications

(43 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Factors that have been reported to influence sex ratio in cattle are the timing of insemination in vivo [35], the maturation stage of the oocyte at the time of in vitro fertilization [15], modifications of the fertilization procedure [20,36], and the postfertilization culture conditions [37].…”

Section: Discussionmentioning

confidence: 99%

In vitro and in vivo quality of bovine embryos in vitro produced with sex-sorted sperm

et al. 2012

View full text Add to dashboard Cite

In this work we analyzed the effects of three culture systems on developmental ability of bovine embryos in vitro produced with sexed sperm, the survival to vitrification (cryologic vitrification method) of such blastocysts, and their pregnancy rates after embryo transfer to recipients, both as fresh and after vitrification/warming. Finally, we measured the accuracy of the sorting protocol by a polymerase chain reaction-based method to validate the embryo sex at blastocyst stages. We confirmed an individual effect of the bull as well as development rates of embryos produced with sorted sperm lower than embryos with unsorted sperm, independent of the culture system used. The cryoresistance to vitrification of embryos produced with sexed sperm did not differ from that of conventionally produced embryos (re-expansion rates at 24 and 48 h: 74.6% vs. 75.5%, and 64.5% vs. 68.1% for embryos produced with conventional and sorted sperm, respectively; hatching rates at 48 h: 63.55% vs. 55.5% for embryos produced with conventional and sorted sperm, respectively). Finally, no significant differences were found in pregnancy rates after the embryo transfer of fresh and vitrified/warmed blastocysts (52.8% vs. 42.0%, respectively; P Ͼ 0.05). Male and female embryos produced with sorted sperm showed the same quality in terms of developmental ability, cryoresistance, and pregnancy rates after transfer. Our culture system, coupled with the vitrification in fiber plugs, provides good quality sex-known embryos which survive vitrification at similar rates than embryos produced with conventional unsorted sperm; also it produces good pregnancy rates after transfer of sexed embryos both fresh and after vitrification and warming.

show abstract

Section: Discussionmentioning

confidence: 99%

In vitro and in vivo quality of bovine embryos in vitro produced with sex-sorted sperm

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Martinez et al [13] showed that the sex ratio of calves could be altered by the timing of AI, with early insemination during estrus resulting in more females and late insemination resulting in more males. However, we reported that changing the timing of AI did not influence the sex ratio of embryos collected from superovulated heifers [14].…”

Section: Discussionmentioning

confidence: 99%

“…Numerous efforts have been directed toward developing procedures for skewing the sex of offspring [10][11][12][13]. However, it is difficult to reach a clear conclusion from the literature, as different laboratories report conflicting results under similar conditions.…”

mentioning

confidence: 99%

Subjecting Holstein Heifers to Stress During the Follicular Phase Following Superovulatory Treatment May Increase the Female Sex Ratio of Embryos

Ideta

Hayama

Kawashima

et al. 2009

Journal of Reproduction and Development

View full text Add to dashboard Cite

Abstract. The sex ratio of mammals has previously been shown to be affected by maternal stress. In our previous study, the proportion of female embryos collected from superovulated and artificially inseminated Holstein heifers that were frequently placed in stanchions and subjected to transrectal examinations of the ovaries during the follicular phase tended to be higher than the expected 50%. The goal of the present study was to test the validity of this observation using a greater number of heifers. Superovulated heifers were artificially inseminated at 56 and 72 h after PGF2α treatment using a single batch of frozen semen. Frequent capture (FC), transrectal examination and/or blood sampling were performed at 4-h intervals from 36 to 76 h after PGF2α treatment (n=13). Nine heifers were used as the Control (non-treatment). Seven-day-embryos were recovered by uterine flushing. Male and female embryos were separated using the loop-mediated isothermal amplification procedure. The proportion of female transferable embryos in the FC group (67.8%, 78/115) was significantly higher than that in the Control group (51.2%, 43/84, P<0.05). The peak concentration of plasma cortisol during the follicular phase following superovulatory treatment was 20.6 ng/ml in the FC group. These results suggest that subjecting heifers to stress during the follicular phase following superovulatory treatment may increase the female sex ratio of embryos.

show abstract

“…Martinez et al [16] found that early insemination during estrus results in more females and that late insemination results in more males; however, the reason why the different timings of AI skew the sex ratio is not well understood. It is possible that X and Y chromosome-bearing spermatozoa have many physiological differences due to differences in motility [29], timing of capacitation [30] and survival time [31] in the bovine reproductive tract.…”

Section: Discussionmentioning

confidence: 99%

“…However, Martinez et al [16] showed that the sex ratio of calves could be altered by the timing of AI, with early insemination during estrus resulting in more females and late insemination resulting in more males. The authors speculated that Y chromosome-bearing spermatozoa are capacitated and decapacitated before the X chromosome-bearing spermatozoa.…”

mentioning

confidence: 99%

Relationships among Estrous Behavior, Superovulatory Response and Grade 1 Embryo Sex Ratio in Superovulated Holstein Heifers

Ideta

Hayama

Urakawa

et al. 2007

Journal of Reproduction and Development

View full text Add to dashboard Cite

Abstract. Abstract. In this study, we first attempted to determine whether the timing of artificial insemination affects the sex ratio of seven-day-old embryos in superovulated Holstein heifers. The superovulatory treatment consisted of eight decreasing doses of FSH for 4 days and 2 doses of PGF2α given with the last two doses of FSH. The superovulated heifers were given a GnRH analogue 48 h after the first PGF2α treatment and were artificially inseminated 48 h (n=10) or 56 h (n=8) after the first PGF2α treatment. There were no significant differences in the percentages of unfertilized ova and transferable embryos (grades 1 to 3) between the two groups. The proportions of female grade 1 embryos did not significantly differ from the expected ratio of 50:50 (49.3% at 48 h and 52.5% at 56 h). We then compared the estrous behavior and superovulatory responses of the heifers with a proportion of female embryos of 50% or less (n=7, Low group) to those of the heifers with a proportion of female embryos of more than 50% (n=9, High group). The Low group had a longer duration of estrus and a higher superovulatory response than the High group. These findings offer little encouragement for prediction of the population of female embryos collected from superovulated heifers. Further studies are necessary to evaluate to what degree maternal hormone levels are related to estrus duration and sex ratio. Key words: Estrous behavior, Sex ratio, Superovulation, Superovulatory response (J. Reprod. Dev. 53: [1015][1016][1017][1018][1019][1020][1021] 2007) he dairy and beef industries mainly use female or male animals, respectively. Numerous efforts have been directed toward developing procedures to skew the sex of offspring [1][2][3]; however, it is difficult to draw clear conclusions from the literature, as different laboratories have reported conflicting results under similar conditions. Significant enrichment of X chromosome-bearing spermatozoa has only been demonstrated by sex selection of spermatozoa based on chromatin differences (cell sorting by flow cytometry) [4]; however, this procedure is not widely used due to the cost of the equipment and the limitations in relation to sorting rate.On the other hand, the sex ratio of offspring has been altered for several species by varying the timing of insemination, such as in humans [5,6], hamsters [7,8], mice [9] and sheep [10]. In cattle, some researchers have shown that varying the timing of artificial insemination (AI) does not influence embryo sex ratio [11,12]. The overall sex ratio of bovine embryos produced in vivo and in vitro does not differ from the expected ratio of 50:50 [13][14][15].

show abstract

Effect of the interval between estrus onset and artificial insemination on sex ratio and fertility in cattle: a field study

Cited by 46 publications

References 28 publications

In vitro and in vivo quality of bovine embryos in vitro produced with sex-sorted sperm

In vitro and in vivo quality of bovine embryos in vitro produced with sex-sorted sperm

Subjecting Holstein Heifers to Stress During the Follicular Phase Following Superovulatory Treatment May Increase the Female Sex Ratio of Embryos

Relationships among Estrous Behavior, Superovulatory Response and Grade 1 Embryo Sex Ratio in Superovulated Holstein Heifers

Contact Info

Product

Resources

About