Age, Dose of FSH and Other Factors Affecting Superovulation in Holstein Cows

Abstract

Effects of age of donor and other factors on superovulation and production of transferable embryos were investigated. Data were obtained on 987 recoveries of embryos performed between November 1980 and June 1984 by Select Embryos, Inc. The 339 Holstein donors ranged in age from 1.8 to 17.8 yr. The effects of age of donor and dose of follicle stimulating hormone (FSH) were examined using regression analysis. For on-farm recoveries, numbers of embryos, rates of fertilization, quality scores of all embryos and numbers of transferable embryos decreased (P less than .01, P less than .001, P less than .05, P less than .01, respectively) with increasing age of donor. For in-clinic recoveries, numbers of embryos plus ova recovered were affected by age of donor, dose of FSH and the interaction of the two (P less than .05). Among older donors, increasing doses of FSH were associated with an increase in the number of ova plus embryos recovered. However, among younger donors, increasing doses of FSH had a negative effect. Numbers of embryos, rates of fertilization and numbers of transferable embryos decreased (P less than .05) with advancing age and increased (P less than .05) with increasing doses of FSH. Greater numbers of ova plus embryos were recovered when treatment with FSH was begun on d 10 or 11 as compared with d 7, 8, 9, 12, 13 or 14 (P less than .001). It was concluded that an increase in age of donor had a negative influence on the success of superovulation and the production of transferable embryos, and that the response to FSH was affected by age of donor.

Improvement of dairy cow embryo yield with low level laser irradiation

“…According to Looney (1986), in a study conducted on 2048 donor cows, 70% of the embryos were collected from only 30% of the donors. Similar variability was reported for a group of more than 900 dairy cows (Lerner et al 1986). …”

Influence of Factors during Superovulation on Embryo Production in Korean Holstein Cattle

“…Mean values of donor parity, milk production and postparturient day after ER were not statistically different among the groups. Increasing parity did not affect ERs or TEs as in previous studies [9,12,22], even though a large-scale parity analysis could not be done in Korea. Milk yield was not related to the production of TEs.…”

“…Moreover, the season when ER was conducted in this study had no significant effect on the production of TEs, but other studies of the effect of season on the superovulatory response of cattle have yielded conflicting results. While some researchers [15,22] have reported an influence of season on superovulatory response, others [25,28] did not find a consistent effect of season on ovarian response. Therefore, it is suggested that the conventional parameters did not influence the superovulatory response and that they could not be used as indicators of donor selection in Korean Holstein cattle.…”

“…Thus, many research studies have focused on inducing additional ovulations in cattle, and during the past half-century, this has been a major consideration in development of commercially acceptable ET technology. Many reports have identified important factors affecting superovulation response in donor cattle: 1) breed and individuals [9], 2) gonadotropins [20,24,26], 3) season and temperature [3,28] and 4) age and nutrition [1,22].…”

Effect of follicular wave synchronization on superovulatory response of Girolando embryo donors

“…A study conducted by Lerner et al (1986) with 339 Holstein donors reported that the increased donor age reduces the number of recovered structures and viable embryos. An alternative proposed by these authors to change this situation would be to increase the FSH dose, but this increase did not have the same result in heifers.…”