Consequences of transfer of an in vitro-produced embryo for the dam and resultant calf

Abstract

No reports exist on consequences of in vitro production (IVP) of embryos for the postnatal development of the calf or on postparturient function of the dam of the calf. Three hypotheses were evaluated: calves born as a result of transfer of an IVP embryo have reduced neonatal survival and altered postnatal growth, fertility, and milk yield compared with artificial insemination (AI) calves; cows giving birth to IVP calves have lower milk yield and fertility and higher incidence of postparturient disease than cows giving birth to AI calves; and the medium used for IVP affects the incidence of developmental abnormalities. In the first experiment, calves were produced by AI using conventional semen or by embryo transfer (ET) using a fresh or vitrified embryo produced in vitro with X-sorted semen. Gestation length was longer for cows receiving a vitrified embryo than for cows receiving a fresh embryo or AI. The percentage of dams experiencing calving difficulty was higher for ET than AI. We observed a tendency for incidence of retained placenta to be higher for ET than AI but found no significant effect of treatment on incidence of prolapse or metritis, pregnancy rate at first service, services per conception, or any measured characteristic of milk production in the subsequent lactation. Among Holstein heifers produced by AI or ET, treatment had no effect on birth weight but the variance tended to be greater in the ET groups. More Holstein heifer calves tended to be born dead, died, or were euthanized within the first 20d of life for the ET groups than for AI. Similarly, the proportion of Holstein heifer calves that either died or were culled for poor health after 20d of age was greater for the ET groups than for AI. We observed no effect of ET compared with AI on age at first service or on the percentage of heifers pregnant at first service, calf growth, or milk yield or composition in the first 120d in milk of the first lactation. In a second experiment, embryos were produced using 1 of 2 culture media: synthetic oviductal fluid-bovine embryo 1 (SOF-BE1) or Block-Bonilla-Hansen 7 (BBH7). We detected no difference between cows receiving an SOF-BE1 or BBH7 embryo in gestation length, the percentage of cows in which parturition was induced, or the percentage of cows that experienced calving difficulty, retained placenta, prolapse, or metritis. Among Holstein heifers, birth weight was higher for BBH7 calves than for SOF-BE1 calves. Treatment had no significant effect on calf death. Results indicate that calves born as a result of IVP-ET are more likely to experience alterations in birth weight and increased death in early life but that there were few consequences to the dam of carrying a fetus derived by IVP-ET.

Comparison between an exclusive in vitro–produced embryo transfer system and artificial insemination for genetic, technical, and financial herd performance

“…This is similar to the cumulative risk of abortion used in Kaniyamattam et al (2016). The stillbirth risk was 6% for IVP-ET calves (Bonilla et al, 2014) and 3% for calves conceived from AI. Estrus detection, conception, and abortion were triggered stochastically.…”

“…That study did not include genetic and additional benefits from IVP-ET, however. The increased cost includes the expense of the IVP-ET procedures but also higher probabilities of abortion and neonatal death loss (Taverne et al, 2002;Bonilla et al, 2014). Given the genetic benefits but greater costs, it is not clear how exclusive IVP-ET systems compare with exclusive AI systems regarding genetic, technical, and financial performance.…”

Long term effects of ART: What do animals tell us?

“…In terms of production characteristics, carcass weight (Patterson, Steen, & Kilpatrick, ), and fertility (Bonilla et al, ) are not affected by IVP although milk yield tends to be lower in cows born after IVP using reverse X‐sorted semen compared to IVP controls (Siqueira et al, ).…”

“…Thus, it is difficult to perform long term monitoring of these animals and only clinically visible effects observed in young animals are generally reported. Adverse neonatal and adult health outcomes are not reported by the bovine industry (Blondin, 2016), although higher calf birth weight are still observed (Bonilla, Block, Denicol, & Hansen, 2014). Moreover, calves born after IVP using reverse X-sorted semen are heavier compared to calves born after artificial insemination, whereas calves born after IVP with conventional semen have an intermediate birthweight (Siqueira, Dikmen, Ortega, & Hansen, 2017).…”

Epigenetics and developmental programming of welfare and production traits in farm animals

“…However, a large study (comprising 426 ET recipients) in Florida, involving the transfer of fresh or frozen-thawed and sexed IVP embryos versus AI in Holstein cows, found no effects of ART on pregnancy rates to first service or daily milk yields during first lactation in resultant female offspring (Bonilla et al 2014). Consequently, it is unlikely that these traits would be affected in beef cattle.…”