Variations in metabolic parameters of matured porcine oocytes after vitrification-warming.

Background: As the porcine oocyte is the most sensitive to low-temperature damage, it has been difficult to cryopreserve compared to those from other domestic animals. However, at present, vitrification is used as a method for the cryopreservation of both oocytes and embryos in this species.

Aim: Our aim was to analyze alterations in metabolic parameters in vitrified-warmed matured porcine oocytes at different post-warming recuperation times.

Dehydration of llama sperm using different osmolarity media and temperatures for preservation.

The objective of this study was to evaluate effects of dehydration on sperm DNA with the aim of eventually using this method for preserving llama spermatozoa. Two experiments were conducted: 1) sperm preservation at 5 °C for 60 days in different hyperosmotic solutions (500, 800, 1000 and 1200 mOsmol/l) (n = 6, replications = 2) and 2) sperm preservation at 5 and -20 °C for 60 days in the same hyperosmotic solutions, with supplementary antibiotics (n = 6, replications = 2). Sperm motility, membrane functional integrity, viability and morphology were evaluated at 0 and 48 h of the preservation period (Experiment 1) and at 30 min and 24 h (Experiment 2).

Air-Drying Llama Sperm Affects DNA Integrity.

The objective of this study was to evaluate the effects of air-drying preservation on llama sperm DNA. Semen collections were carried out using electroejaculation under general anesthesia. A total of 16 ejaculates were processed from 4 males ( = 4, = 4).

In vitro production of porcine zygotes using intracytoplasmic injection of vitrified sperm.

The objectives of this study were to evaluate if vitrified porcine spermatozoa are able to maintain their capacity to produce zygotes in vitro using intracytoplasmic sperm injection (ICSI) and to evaluate the zygote development in two in vitro atmospheric conditions: 5% CO and tri-gas. A group of porcine oocytes maturated in vitro were injected with vitrified-warmed sperm (treatment group) and another group, with sperm diluted and conserved at 17°C (control group). To evidence parthenogenetic activation, some oocytes were submitted to a Sham test.

Comparison of two cooling protocols for llama semen: with and without collagenase and seminal plasma in the medium.

Seminal plasma (SP) of South American Camelids could interfere with the interaction of spermatozoa with the extenders; therefore it becomes necessary to improve semen management using enzymatic treatment. Our objective was to compare two cooling protocols for llama semen. Twelve ejaculates were incubated in 0.

Effect of cryoprotectant and equilibration temperature on cryopreservation of Lama glama spermatozoa.

The aim of this study was to determine the effect of two equilibration temperatures (5 °C and room temperature) and two cryoprotectants (glycerol and dimethylformamide, both at 7%) on llama sperm cryopreservation. Llama ejaculates were divided into four aliquots. A lactose-EDTA-egg yolk (LEEY) extender with either 7% glycerol (LEEY-G) or 7% dimethylformamide (LEEY-DMF) was added to two of the aliquots, which were equilibrated for 20 min at room temperature and subsequently frozen.

First llama (Lama glama) pregnancy obtained after in vitro fertilization and in vitro culture of gametes from live animals.

The aim of this study was to evaluate the developmental competence and pregnancy rate of llama hatched blastocysts produced in vitro using gametes from live animals and two different culture conditions. Fifteen adult females were superstimulated with 1500 IU of eCG, eleven (73%) responded to the treatment and were used as oocyte donors. Follicular aspiration was conducted by flank laparotomy.

Evaluation of DNA fragmentation in llama (Lama glama) sperm using the sperm chromatin dispersion test.

The integrity of sperm chromatin is now viewed as an important factor in male fertility and in early embryonic development. The objectives of this study were: (1) adapt the simple and inexpensive sperm chromatin dispersion (SCD) test to evaluate DNA fragmentation in llama sperm and establish the halo patterns observed in this species, (2) determine an effective and reliable positive control for this technique and (3) evaluate correlation between the SCD test and the toluidine blue (TB) stain. To adapt the SCD test, three different mercaptoethanol (ME) concentrations were assayed (2.