Male reproductive biotechnologies in South American Camelids Part II: Semen dilution, cryopreservation and artificial insemination.

Even though South American Camelids (SAC) are a rustic species, adapted to harsh environments, their ability to reproduce is low in their natural habitat. Conception and birth rates in camelids vary from 50 % to 90 %. This depends on the mating system used, sire and dam fertility, postpartum interval, environmental conditions, and nutrition.

Cooling of alpaca spermatozoa using an extender with the addition of different percentages of seminal plasma.

The objective of this study was to evaluate the effect of the addition of different percentages of seminal plasma (SP) during the cooling at 5 °C of alpaca spermatozoa from vas deferens. Fifteen pools of sperm from vas deferens were evaluated and then divided into four aliquots that were diluted to a final concentration of 30 × 10 sperm/ml with either: (1) Tris with 20% egg yolk (T-EY) (control, 0% SP), (2) T-EY with 10% SP, (3) T-EY with 25% SP, and (4) T-EY with 50% SP. Samples were cooled at 5 °C and the following sperm parameters were evaluated after 24 and 48 h of storage: motility, viability, membrane function, acrosome integrity, morphology, and chromatin condensation.

Use of commercial extenders, with and without the addition of egg yolk, for cooling llama semen.

The objective of this study was to evaluate the effect of two commercial extenders, AndroMed® (AM) and Androstar® Plus (AS) both with and without the addition of egg-yolk (EY), for cooling llama semen. A total of sixteen ejaculates were collected from four males. Each ejaculate was divided into four aliquots and diluted with: AM, AM with 20 % EY (AM-EY), AS and AS with 20 % EY (AS-EY) and then cooled to 5 °C in an Equitainer®.

Cryopreservation of llama semen using a combination of permeable cryoprotectants.

Semen cryopreservation is not available for massive use in South American Camelids (SACs) due to the lack of an efficient protocol and the low pregnancy rates obtained with artificial insemination (AI). The use of a single cryoprotectant (CP) is commonly used in SACs frozen semen. The objective of the study was to evaluate the combined cryoprotective capacity of two permeable CPs at different stages of the cryopreservation protocol in llama semen.

Use of Androcoll-E to Separate Frozen-Thawed Llama Sperm From Seminal Plasma and Diluent.

It is not easy to separate frozen-thawed South American camelid sperm from seminal plasma (SP) and diluents to be used for embryo production. The objective of this study was to evaluate Androcoll-E™ (AE) efficiency to separate llama sperm from SP and freezing extender in frozen-thawed semen. A total of 22 ejaculates from five males were collected using electroejaculation.

Comparison of Extenders With the Addition of Egg Yolk for Cooling Alpaca Sperm Obtained From Deferent Ducts.

The use of non-commercial and commercial extenders for cooling alpaca sperm has already been reported, the latter showing certain advantages over the first. The Andromed® (AM) extender was created for use in ruminants and has also been tested in ejaculated and epididymal alpaca sperm. According to the manufacturer, this extender does not need the addition of egg yolk (EY); however, it is known that the addition of EY to some extenders improves the preservation of cooled sperm.

Incubation of frozen-thawed llama sperm with seminal plasma.

Seminal plasma is intimately connected to sperm physiology and particularly in South American Camelids, has demonstrated to be involved in multiple physiological reproductive events. Different percentages of seminal plasma (0%, 10% and 50%) were added to thawed llama semen samples with the objective of evaluating the interaction with cryopreserved sperm over time (0, 1.5 and 3 hr at 37°C).