Evaluation of equine semen frozen in extenders free of egg yolk using two different freezing curves.

A chemically defined cryopreservation extender that maintains seminal parameters is relevant. Fifteen ejaculates from 5 stallions (n= 5; r=3) were diluted in 5 extenders: 1) EDTA-glucose based extender with egg-yolk and dimethylformamide (EY); 2) commercial equine extender (CE); 3) CE with dimethylformamide (CE-3); 4) bovine commercial extender with liposomes (OP); 5) bovine commercial extender with soybean lecithin (BIO), and frozen using a slow and a rapid temperature descent curve. Post-thaw evaluations were: sperm kinematic parameters, viability and acrosome status, membrane lipoperoxidation and DNA fragmentation.

A portable and affordable aligner for the assembly of microfluidic devices.

The incorporation of sophisticated capabilities within microfluidic devices often requires the assembly of different layers in a correct arrangement. For example, when it is desired to include electrodes inside microfluidic channels or to create 3D microfluidic structures. However, the alignment between different substrates at the microscale requires expensive equipment not available for all research groups.

In vitro Inhibitory Activity of IgY Antibodies Against Salmonella Ser. Newport Isolated from Horses.

Equine salmonellosis is caused by several Salmonella serotypes, including Salmonella Newport, which cause enterocolitis and diarrhea. Treatment usually includes the administration of antibiotics. However, since multidrug-resistant Salmonella is commonly detected, alternative options to control the pathogen are needed.

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).

Uterine and Corpus Luteum Blood Flow Evaluation Prior to Uterine Flushing in Llama Embryo Donors.

The aim of this study was to assess the uterine blood flow (UBF) and corpus luteum blood flow (CLBF) in llamas 8 days post-mating, using color-Doppler ultrasonography (CDU), to determine the possible relationship between vascularization and the presence of an embryo. Adult females ( = 25) were used to monitor ovarian dynamics by palpation and transrectal ultrasonography until detection of a ≥6 mm growing follicle. Females were randomly assigned to one of two groups: Group I ( = 19), were mated and ovulation was induced by a single dose of buserelin (GnRH analog) that same day (Day 0); and Group II ( = 6), only ovulation was induced (control).

Plasma IGF1 and 17β-Estradiol Concentrations During the Follicular Wave in Llamas.

The aim of this study was to characterize the temporal association between follicular waves and circulating concentrations of 17β-estradiol (E2) and IGF1 in llamas. Follicular waves could be clearly divided in three phases: growth, plateau and regression; with a mean duration of 18.8 ± 0.

Apoptosis in porcine cumulus-oocyte complexes: Relationship with their morphology and the developmental competence.

The aim of this study was to assess the presence and distribution of apoptosis in porcine cumulus-oocyte complexes (COCs) and its relations with COC morphology and developmental competence. The COCs were obtained from slaughterhouse ovaries, classified into A1 (top category), A2, B1, B2, C, and D based on their morphology. A1, A2, and B1 were matured and fertilized in vitro, and blastocyst rate was compared among them.

Corpus luteum vascularization during the maternal recognition of pregnancy in llamas (Lama glama).

The aim of this study was to characterize corpus luteum vascularization and its association with plasma progesterone concentration in early stages of pregnancy, when maternal recognition of pregnancy is expected to occur. In all animals, both plasma progesterone concentration and corpus luteum vascularization increased from Day 6 to Day 8 post-mating and afterwards in non-pregnant llamas they started to decrease to reach basal levels around Days 12 to 14 post-mating, while in pregnant animals, both variables remained elevated until the end of the study. A lineal positive relationship between corpus luteum vascularization and plasma progesterone concentration was observed in pregnant (r  = .

Seminal plasma affects the survival rate and motility pattern of raw llama spermatozoa.

Unlabelled: The objectives of this study were to evaluate the effect over time of different percentages of seminal plasma (SP) on llama sperm characteristics in raw semen and correlate the techniques routinely used to evaluate sperm viability and acrosome status with the Fluorescein Isothiocyanate -Arachis hypogea agglutinin/Propidium Iodide (FITC-PNA/PI). Eighteen ejaculates, obtained from 6 male llamas using electroejaculation, were incubated in 0.1% collagenase in HEPES-TALP (HT), centrifuged and resuspended with SP and HT: 0, 10, 50 and 100% SP.

Induction of apoptosis in the bursa of Fabricius by vaccination against Gumboro disease.

Infectious bursal disease is a severe acute viral disease of young chickens, affecting mainly the B-lymphocytes in the bursa of Fabricius, leading to severe immunosuppression as a result of the death of lymphoid cells. In the bursa infected with infectious bursal disease virus, viral replication is associated with apoptosis of lymphoid cells, inflammatory change and atrophy. Vaccination has appeared to be a crucial factor for control, with live attenuated vaccines being the most used.

Porcine sperm vitrification II: Spheres method.

Owing to current problems in boar sperm cryopreservation, this study proposes to evaluate vitrification in spheres as an alternative cryopreservation procedure, comparing the use or not of permeable cryoprotectants and two warming methods. Extended (n = 3; r = 4) and raw (n = 5; r = 2) porcine spermatozoa were diluted in media, in the absence or presence of either 4% dimethylformamide or 4% glycerol, to a final concentration of 5 × 10  spermatozoa/ml and vitrified using the spheres method. Two warming procedures were evaluated: a rapid method (30 s at 37°C) and an ultrarapid method (7 s at 75°C, followed by 30 s at 37°C).

Porcine sperm vitrification I: cryoloops method.

The aims of this study were to evaluate porcine sperm vitrification in cryoloops, with and without two different cryoprotectants and assess two warming procedures. Extended (n = 3; r = 4) and raw (n = 5; r = 2) semen was diluted in media without and with cryoprotectants (4% dimethylformamide and 4% glycerol) to a final concentration of 20 × 10 spermatozoa ml and vitrified using the cryoloops method. Two warming procedures were evaluated: rapid method (30 s at 37°C) and an ultra-rapid method (7 s at 75°C, followed by 30 s at 37°C).

Comparison of differents methods of sperm selection of llama raw semen.

The objective of this study was to compare the efficiency of different sperm selection methods applied to the same llama ejaculate. Four treatments were compared: two variants of the swim up technique (with and without seminal plasma), and two different colloids, Androcoll-E-Large and Percoll(®). Using electroejaculation, 21 semen samples were obtained from 7 llama males (n=7, r=3).

In vitro equine embryo production using air-dried spermatozoa, with different activation protocols and culture systems.

The aim of this work was to evaluate the use of air-dried spermatozoa for in vitro production of equine embryos and verify if sperm extract activation and in vivo culture improve in vitro embryo production. Cooled spermatozoa (control) and air-dried spermatozoa stored for 2, 14 or 28 days were used for ICSI sperm extract, or ionomycin was used for oocyte activation, and embryos were in vitro or in vivo (in mare's oviduct) cultured for 7 days. With in vitro culture, cleavage rate was higher when activating with sperm extract (P < 0.

Hypo-osmotic test in cat spermatozoa.

The hypo-osmotic (HOS) test has been used in other species as an indicator of the fertilising capacity of spermatozoa. The aims of this study were to assess the response of domestic cat spermatozoa to the hypo-osmotic test, to determine the type of solution, concentration and time of incubation needed to obtain a maximum percentage of swelling, to correlate the selected combination with the percentages of progressive motility and to evaluate whether dilution of the ejaculate alters the results. Incubation for 30 and 45 min in solutions of fructose and of citrate of 50 and 100 mOsmol kg⁻¹ was evaluated.

Development of an artificial insemination protocol in llamas using cooled semen.

The objective of this study was to design an AI protocol using cooled semen to obtain pregnancies in the llama. Each raw ejaculate was subdivided into four aliquots which were extended 1:1 with: (1) 11% lactose-egg yolk (L-EY), (2) Tris-citrate-fructose-egg yolk (T-F-EY), (3) PBS-llama serum (S-PBS) and (4) skim milk-glucose (K). Each sample reached 5°C in 2.

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.

Morphometric analysis of llama (Lama glama) sperm head.

Llama production in Argentina has increased, as the international interest in breeding this type of animals has grown in the last years. Considering the great polymorphism that llama spermatozoa present at evaluation using light microscopy, the aim of this study was to objectively evaluate llama sperm head morphometry using digital morphometric analysis. Five ejaculates from each of eight males were obtained to evaluate morphometric parameters of 8000 sperm heads stained with Tinción 15(®).

Evaluation of Lama glama semen viscosity with a cone-plate rotational viscometer.

Llama semen is highly viscous. This characteristic is usually evaluated subjectively by measuring the thread formed when carefully pippeting a sample of semen. The aims of this study were (i) to objectively determine and analyse llama semen viscosity, (ii) to compare semen viscosity between ejaculates of the same male as well as between different males, (iii) to study the correlation between viscosity and other semen characteristics and (iv) to evaluate the effect of collagenase on semen viscosity.

Evaluation of the effect of cooling and of the addition of collagenase on llama sperm DNA using toluidine blue.

The effect cryopreservation has on sperm chromatin condensation has been studied in many species but not in South American camelids. The objectives of this study were to evaluate with toluidine blue (TB) the effects of cooling and of adding collagenase on llama sperm DNA condensation. The optimum incubation time (30 s, 1.

Embryo transfer technique: Factors affecting the viability of the corpus luteum in llamas.

The aim of the present study was to evaluate the effect of the embryo transfer (ET) maneuvers on plasma progesterone concentrations in recipient Lama glama females and the relationship between the site the embryo was transferred to and corpus luteum (CL) localization. Experiment I (effect of transcervical threading): adult non-pregnant, non-lactating llama females were randomly assigned into two groups: control group (without cervical threading, n=10) and group A (with cervical threading, n=10). In both groups, CL activity was evaluated through measurement of progesterone plasma concentrations.

Improvement of llama (Lama glama) seminal characteristics using collagenase.

Llama semen is characterized by great structural viscosity and minimal sperm progressive motility. These characteristics, inherent to South American Camelid ejaculates, have slowed down the development of assisted reproductive techniques in these species. The aim of the present research was to evaluate the effect of different combinations of dilutions and incubation time with H-TALP-BSA medium, with and without adding 0.

Collection method, season and individual variation on seminal characteristics in the llama (Lama glama).

The objective of the present study was to evaluate the effect of semen collection method (electroejaculation "EE" as compared with the artificial vagina "AV"), the season (summer versus winter) and the male used on macroscopic and microscopic characteristics of ejaculates in llamas. A total of 110 ejaculates were collected from six males and 92 of them were analyzed. Ejaculate volume, concentration, total sperm and the following sperm characteristics were studied: motility, membrane function (HOS test), membrane integrity (CFDA/PI fluorochromes) and morphology.