Birth of a Live Cria After Transfer of a Vitrified-Warmed Alpaca (Vicugna pacos) Preimplantation Embryo

Abstract

The alpaca (Vicugna pacos) is an important species for the production of fiber and food. Genetic improvement programs for alpacas have been hindered, however, by the lack of field-practical techniques for artificial insemination and embryo transfer. In particular, successful techniques for the cryopreservation of alpaca preimplantation embryos have not been reported previously. The objective of this study was to develop a field-practical and efficacious technique for cryopreservation of alpaca preimplantation embryos using a modification of a vitrification protocol originally devised for horses and adapted for dromedary camels. Four naturally cycling non-superovulated Huacaya females serving as embryo donors were mated to males of proven fertility. Donors received 30 μg of gonadorelin at the time of breeding, and embryos were non-surgically recovered 7 days after mating. Recovered embryos (n = 4) were placed individually through a series of three vitrification solutions at 20°C (VS1: 1.4 M glycerol; VS2: 1.4 M glycerol + 3.6 M ethylene glycol; VS3: 3.4 M glycerol + 4.6 M ethylene glycol) before loading into an open-pulled straw (OPS) and plunging directly into liquid nitrogen for storage. At warming, each individual embryo was sequentially placed through warming solutions (WS1: 0.5 M galactose at 37°C; WS2: 0.25 M galactose at 20°C), and warmed embryos were incubated at 37°C in 5% CO2 in humidified air for 20–22 h in 1 ml Syngro® holding medium supplemented with 10% (v/v) alpaca serum to perform an initial in vitro assessment of post-warming viability. Embryos whose diameter increased during culture (n = 2) were transferred individually into synchronous recipients, whereas embryos that did not grow (n = 2) were transferred together into a single recipient to perform an in vivo assessment of post-warming viability. Initial pregnancy detection was performed ultrasonographically 29 days post-transfer when fetal heartbeat could be detected, and one of three recipients was pregnant (25% embryo survival rate). On November 13, 2019, the one pregnant recipient delivered what is believed to be the world's first cria produced from a vitrified-warmed alpaca embryo.

New Alternative Mixtures of Cryoprotectants for Equine Immature Oocyte Vitrification

“…Besides these disaccharides, which have been the only non-permeating CPAs tested in equine oocytes vitrification up to now (for review, De Coster & Angel-Velez, et al, 2020 [ 5 ]), monosaccharides may provide a valuable alternative. Monosaccharides (galactose, fructose, glucose) seem to be more effective osmotic buffers than disaccharides during vitrification and warming [ 34 ], and they have been used successfully for the vitrification of bovine [ 35 ] and feline [ 36 ] oocytes, as well as for bovine [ 37 ], porcine [ 38 ], dromedary camel [ 39 ], alpaca [ 40 ], and equine embryos [ 37 , 41 , 42 ].…”

Innovations in cryoconservation of animal genetic resources

“…alpaca (Vicugna pacos) Birth of a live cria after transfer of a vitrified-warmed alpaca (Vicugna pacos) preimplantation embryoLutz et al, 2020 …”

Zoonotic diseases of potential concern among alpacas MONIKA

“…Over the past three decades, international interest in breeding alpacas and other SACs has grown, partly due to demand for their fine fleece; the global SAC population in 2020 was estimated to be over 9.1 million individuals (FAOSTAT 2018, Available online at: http://www.fao.org/faostat/en/#data/QA (accessed October 13, 2020), 44) with the largest population of alpacas in Europe being in Great Britain, with around 35,000 individuals (http://www.bas-uk.com/). A significant increase in alpaca breeding has also been noted in Poland.…”