Shadows of structured beams in lenslike media.

The self-healing phenomenon of structured light beams has been comprehensively investigated for its important role in various applications including optical tweezing, superresolution imaging, and optical communication. However, for different structured beams, there are different explanations for the self-healing effect, and a unified theory has not yet been formed. Here we report both theoretically and experimentally a study of the self-healing effect of structured beams in lenslike media, this is, inhomogeneous lenslike media with a quadratic gradient index. By observing the appearance of a number of shadows of obstructed structured wave fields it has been demonstrated that their self-healing in inhomogeneous media are the result of superposition of fundamental traveling waves. We have found that self-healing of structured beams occurs in this medium and, interestingly enough, that the shadows created in the process present sinusoidal propagating characteristics as determined by the geometrical ray theory in lenslike media. This work provides what we believe to be a new inhomogenous environment to explain the self-healing effect and is expected to deepen understanding of the physical mechanism.

Symmetric gradient-index media reconstruction.

Ray tracing in gradient-index (GRIN) media has been thoroughly studied and several ray tracing methods have been proposed. Methods are based on finding the ray path given a known GRIN. In recent decades, the inverse problem, which consists of finding the GRIN distribution for a given light ray path, has been gaining attention. Given that it is not an easy task, the methods proposed in the literature vary in degrees of difficulty. In this work, an alternative method is presented to derive symmetric GRIN distributions whose implementation can be considered the simplest to date. Since it is based on invariants, which result from the symmetries of the system as stated by Fermat's principle, it is an exact numerical method, i.e., the physical system is not approximated. The robustness of the method permits the reconstruction of the GRIN distribution from a ray propagating in three-dimensions. In order to demonstrate its operation, different known symmetric GRIN media are reconstructed using rays that propagate in two and three dimensions.

YouTube® in Spanish as an information source for patients with autoimmune hepatitis.

INTRODUCTION AND AIM: A large number of patients with autoimmune hepatitis (AH) seek information about their disease on the Internet. The reliability, comprehensiveness, and quality of said information in Spanish has not been studied. Our aim was to describe the characteristics of the information about AH on YouTube®. METHODS: An analytic observational study evaluated videos in Spanish about AH available on YouTube®, describing their general characteristics, viewer engagement, and information sources. Standardized tools were utilized to analyze reliability (DISCERN), comprehensiveness, and overall quality (Global Quality Score [GQS]). RESULTS: One hundred videos were included, 93% of which provided information from healthcare professionals (group 1), and 7% of which reflected patient opinions (group 2). There were differences in the median reliability (DISCERN 4 vs 2, p ≤ 0.05) and comprehensiveness (4 vs 2, p ≤ 0.05) scores between groups, but equal overall quality (GQS 3 vs 2, p = 0.2). Reliability (DISCERN 4; RIC 3-4) and comprehensiveness (4.5; IQR 3-5) were higher in videos by professional organizations, compared with those by independent users, healthcare information websites, and for-profit organizations (DISCERN 3; IQR 2.5-3.5) (p < 0.001). Reliability (DISCERN 2; IQR 1.5-3), comprehensiveness (2; IQR 1.5-2.5), and quality (GQS 2.5; IQR 1.5-3.5) were lower for videos made by for-profit organizations. CONCLUSION: The majority of videos about AH in Spanish on YouTube® have good reliability, comprehensiveness, and quality. Videos created by academic organizations had higher scores, thus their collaboration, with respect to patient opinion videos, is suggested.

YouTube® in Spanish as a source of information for patients with inflammatory bowel disease.

INTRODUCTION AND AIM: The majority of patients with inflammatory bowel disease (IBD) seek information about their disease on the Internet. The reliability, comprehensiveness, and quality of said information in Spanish has not previously been studied. MATERIALS AND METHODS: An analytic observational study was conducted that included YouTube® videos on IBD available in Spanish, describing general characteristics, engagement, and sources. Standard tools for evaluating reliability (DISCERN), comprehensiveness, and overall quality (Global Quality Score, GQS) were employed. RESULTS: One hundred videos were included. Eighty-eight videos consisted of information produced by healthcare professionals (group 1) and 12 included patient opinions (group 2). There were no differences in the median scores for reliability (DISCERN 3 vs 3, p = 0.554) or comprehensiveness (3 vs 2.5, p = 0.768) between the two groups, but there was greater overall quality in the group 2 videos (GQS 3 vs 4, p = 0.007). Reliability was higher for the videos produced by professional organizations (DISCERN 4; IQR 3-4), when compared with healthcare information websites and for-profit agencies (DISCERN 3; IQR 2.5-3.5) (p < 0.001), but the videos with healthcare information website and for-profit sources had a higher quality score (GQS 3 vs 4, p < 0.001). Comprehensiveness scores were similar. CONCLUSION: The majority of YouTube® videos in Spanish on IBD have good reliability, comprehensiveness, and quality. Reliability was greater for the videos produced by professional organizations, whereas quality was higher for those created from healthcare information websites and for-profit agencies.

Geometrical-light-propagation in non-normalized symmetric gradient-index media.

Typically, as a means to obtain a less complicated ray tracing method on a gradient-index (GRIN) medium, a normalization is done. This normalization is based upon the fact that the values of the refractive index on the surface of the GRIN medium and the value of the refractive index medium where it is immersed are the same. In this paper, a Fermat's-ray-invariants-based ray tracing method in a non-normalized GRIN medium is presented. This method is so simple that it is no longer necessary to perform normalization to reduce ray tracing complications in GRIN media. In order to observe its operation, the method is implemented in different GRIN media with rectangular, cylindrical, and spherical symmetry. Also, the method is implemented in two different axicon GRIN lenses. MATLAB codes for the implementations are provided as supplementary files. Finally, it is possible to observe that the Fermat's ray invariant is still preserved even outside the lens. This implies that it is not necessary to apply Snell's law when the ray leaves the GRIN medium, because the conservation of the Fermat's ray invariant performs the refraction as if Snell's law had been applied.

Generalization of ray tracing in symmetric gradient-index media by Fermat's ray invariants.

Ray tracing in gradient-index (GRIN) media has been traditionally performed either by using the analytical or numerical solutions to the Eikonal equation or by creating a layered medium where Snell's law is calculated in each layer. In this paper, an exact general method to perform ray tracing in GRIN media is presented based on the invariants of the system as stated by Fermat's principle when the media presents symmetries. Its advantage, compared with other methods reported in the literature, relies on its easy implementation. Besides the GRIN distribution and the initial conditions of the incident ray, once the invariants of the system are stated the resulting math is simple to solve and interpret. To benchmark the algorithm, ray tracing in typical cases of GRIN media is calculated, finding minimal discrepancies between the analytical solutions and our simulations. The used media are axial refractive index and parabolic index fiber and lenses with spherical gradient-index symmetry, such as: Luneburg's, Gutman's, generalized Maxwell's Fish-eye, Eaton's, and concentrator lenses. Our method can be further applied to distributions with symmetries associated with other common curvilinear orthogonal coordinate systems, in particular to those associated to the separability of the Helmholtz equation that would allow us to investigate wave optics in these GRIN media with the associated geometries.

What are the traveling waves composing the Hermite-Gauss beams that make them structured wavefields?

To the best of our knowledge, at the present time there is no answer to the fundamental question stated in the title that provides a complete and satisfactory physical description of the structured nature of Hermite-Gauss beams. The purpose of this manuscript is to provide proper answers supported by a rigorous mathematical-physics framework that is physically consistent with the observed propagation of these beams under different circumstances. In the process we identify that the paraxial approximation introduces spurious effects in the solutions that are unphysical. By removing them and using the property of self-healing, that is characteristic to structured beams, we demonstrate that Hermite-Gaussian beams are constituted by the superposition of four traveling waves.

Single function crystalline lens capable of mimicking ciliary body accommodation.

The lens is a complex optical component of the human eye because of its physiological structure: the surface is aspherical and the structural entities create a gradient refractive index (GRIN). Most existent models of the lens deal with its external shape independently of the refractive index and, subsequently, through optimization processes, adjust the imaging properties. In this paper, we propose a physiologically realistic GRIN model of the lens based on a single function for the whole lens that accurately describes different accommodative states simultaneously providing the corresponding refractive index distribution and the external shape of the lens by changing a single parameter that we associate with the function of the ciliary body. This simple, but highly accurate model, is incorporated into a schematic eye constructed with reported experimental biometric data and accommodation is simulated over a range of 0 to 6 diopters to select the optimum levels of image quality. Changes with accommodation in equatorial and total axial lens thicknesses, as well as aberrations, are found to lie within reported biometric data ranges.

Kepler's law for optical beams.

It is well known that optics and classical mechanics are intimately related. One of the most important concepts in classical mechanics is that of a particle in a central potential that leads to the Newtonian description of the planetary dynamics. Within this, a relevant result is Kepler's second law that is related to the conservation of orbital angular momentum, one of the fundamental laws in physics. In this paper, we demonstrate that it is possible to find the conditions that allow us to state Kepler's second law for optical beams with orbital angular momentum by analyzing the streamlines of their energy flow. We find that the optical Kepler's law is satisfied only for cylindrical symmetric beams in contrast to the classical mechanics situation that is satisfied for the other conic geometries, namely, parabolic, elliptical and hyperbolic. We propose a novel approach to confirm our analytic results: we observe the propagation of the Arago's spot created by a beam with orbital angular momentum as a local "light-tracer" instead of looking at the propagation of the whole beam. The observed patterns fully agree with the prediction of our formalism.

Intelligent-assistant system for scleral spur location.

A system based on the use of two artificial neural networks (ANNs) to determine the location of the scleral spur of the human eye in ocular images generated by an ultrasound biomicroscopy is presented in this paper. The two ANNs establish a relationship between the distance of four manually placed landmarks in an ocular image with the coordinates of the scleral spur. The latter coordinates are generated by the expert knowledge of a subject matter specialist. Trained ANNs that generate good results for scleral spur location are incorporated into a software system. Statistical indicators and results yield an efficiency performance above 95%.

Topographic synthesis of arbitrary surfaces with vortex Jinc functions.

When a circular aperture is uniformly illuminated, it is possible to observe in the far field an image of a bright circle surrounded by faint rings known as the Airy pattern or Airy disk. This pattern is described by the first-order Bessel function of the first type divided by its argument expressed in circular coordinates. We introduce the higher-order Bessel functions with a vortex azimuthal factor to propose a family of functions to generalize the function defining the Airy pattern. These functions, which we call vortex Jinc functions, happen to form an orthogonal set. We use this property to investigate their usefulness in fitting various surfaces in a circular domain, with applications in precision optical manufacturing, wavefront optics, and visual optics, among others. We compare them with other well-known sets of orthogonal functions, and our findings show that they are suitable for these tasks and can pose an advantage when dealing with surfaces that concentrate a considerable amount of their information near the center of a circular domain, making them suitable applications in visual optics or analysis of aberrations of optical systems, for instance, to analyze the point spread function.

Three-dimensional ray tracing in spherical and elliptical generalized Luneburg lenses for application in the human eye lens.

Ray tracing in spherical Luneburg lenses has always been represented in 2D. All propagation planes in a 3D spherical Luneburg lens generate the same ray tracing, due to its radial symmetry. A geometry without radial symmetry generates a different ray tracing. For this reason, a new ray tracing method in 3D through spherical and elliptical Luneburg lenses using 2D methods is proposed. The physics of the propagation is shown here, which allows us to make a ray tracing associated with a vortex beam. A 3D ray tracing in a composite modified Luneburg lens that represents the human eye lens is also presented.

Composite modified Luneburg model of human eye lens.

A new lens model based on the gradient-index Luneburg lens and composed of two oblate half spheroids of different curvatures is presented. The spherically symmetric Luneburg lens is modified to create continuous isoindicial contours and to incorporate curvatures that are similar to those found in a human lens. The imaging capabilities of the model and the changes in the gradient index profile are tested for five object distances, for a fixed geometry and for a fixed image distance. The central refractive index decreases with decreasing object distance. This indicates that in order to focus at the same image distance as is required in the eye, a decrease in refractive power is needed for rays from closer objects that meet the lens surface at steeper angles compared to rays from more distant objects. This ensures a highly focused image with no spherical aberration.

Vitrification of in vitro mature alpaca oocyte: effect of ethylene glycol concentration and time of exposure in the equilibration and vitrification solutions.

The effect of different ethylene glycol concentrations, times of exposure and vitrification procedure on viability, cleavage and blastocyst rate of in vitro matured alpaca oocytes chemically activated after vitrification was analyzed. In Experiment 1, oocytes were incubated for 12-15 min with different concentrations of ethylene glycol (EG) in the equilibration solution (ES) followed by chemical activation and in vitro cultured for 8 days to determine oocyte viability, cleavage and blastocyst rates. In Experiment 2, oocytes were incubated in the equilibration solution containing 4% of EG for 12-15 min and then randomly assigned to vitrification solutions containing 25, 35 or 45% of EG for 30s, vitrified and stored at -196°C. In Experiment 3, oocytes were incubated in the equilibration solution containing 4% of EG for 12-15 min and then randomly assigned to the vitrification solution containing 35% of EG for 15, 30 or 45s, vitrified and stored at -196°C. For Experiments 2 and 3, non-vitrified and vitrified oocytes were activated and cultured in vitro. In Experiment 1, oocyte viability was lowest at concentrations of 6 or 8%, intermediate at 2 or 4% and highest at 0% of EG. Oocyte viability and cleavage rate were affected by EG concentration, time of exposure in the vitrification solution or vitrification procedure in Experiment 2 and 3. Alpaca oocytes were viable after vitrification, given that oocyte viability, cleavage and blastocyst rate were affected by the vitrification procedure, EG concentration and time of exposure in the equilibration and vitrification solutions.

First report of qacG, qacH and qacJ genes in Staphylococcus haemolyticus human clinical isolates.

OBJECTIVES: To investigate phenotypically and genotypically the presence of MDR efflux pumps in 21 clinical isolates of Staphylococcus haemolyticus collected over a period of 10 years. METHODS: MICs of different antibiotics and biocides were determined by the broth dilution method in the presence/absence of carbonyl cyanide-m-chlorophenylhydrazone (CCCP), an efflux pump inhibitor. PCR followed by sequencing was performed to detect the qac genes that encode for antiseptic resistance. Clonal relationships were determined by PFGE SmaI patterns using a standard protocol. RESULTS: All the isolates were resistant to gentamicin, 15 to erythromycin, 18 to ciprofloxacin, 7 to chloramphenicol and 1 to tetracycline. They showed higher susceptibility to antibiotics when they were exposed to CCCP. The MICs of ethidium bromide, SDS and benzalkonium chloride were also decreased, whereas the MIC of triclosan was decreased in only four isolates in the presence CCCP. Of the 21 isolates, qacA/B was detected in 5 isolates, smr in all of the isolates, qacG in 11 isolates, qacH in 10 isolates and qacJ in 4 isolates. PFGE analysis of the 21 isolates clustered them into 14 clones at 90% similarity corresponding to differences of between 7 and 16 bands among the clones. CONCLUSIONS: The efflux mechanism seems to be an important mechanism to confer resistance to antibiotics and biocides through MDR pumps. It was observed that several qac genes coexist in some of the isolates and seem to act simultaneously in the removal of different compounds out of the bacterial cell. The qac genes are horizontally spread among different clones.

[Effect of the administration of rectal indomethacin on amylase serum levels after endoscopic retrograde cholangiopancreatography, and its impact on the development of secondary pancreatitis episodes]. / Efecto de la administración de indometacina rectal sobre los niveles séricos de amilasa posteriores a colangiopancreatografía retrógrada endoscópica y su impacto en la aparición de episodios de pancreatitis secundaria.

BACKGROUND: Hyperamylasemia and acute pancreatitis represent the most frequent major complication after endoscopic retrograde cholangiopancreatography (ERCP), developing in 1-30% of cases. OBJECTIVE: To determine the incidence of hyperamylasemia and acute pancreatitis after ERCP, and to assess the utility of rectal indomethacin to prevent these events. MATERIAL AND METHODS: A randomized clinical trial. During a 12-month period 150 patients were included. They were divided up into a study group (n = 75), where 100 mg of rectal indomethacin were administered 2 hours prior to the procedure, and a control group (n = 75), which received rectal glycerin. Two hours after ERCP serum amylase levels were measured and classified as follows: 0or=600 IU/L. Clinical pancreatitis episodes were quantified and classified according to Ranson's criteria. RESULTS: Gender distribution: 100 women and 50 men. Mean age: 55.37 +/- 18.0 for the study group, and 51.1 +/- 17.0 for the control group. A diagnosis of benign pathology was present in 56 (74.7%) cases in the study group, and 59 (78.7%) controls. After ERCP 13 (17.3%) patients in the study group and 28 (37.3%) in the control group developed hyperamylasemia (p (2) 0.05). Hyperamylasemia > 600 IU/L was found in 3 patients in the study group, and in 10 in the control group (p = 0.001). Mild pancreatitis was detected in 4 (5.3%) patients in the study group, and in 12 (16%) patients in the control group (p = 0.034). There were no deaths or adverse drug reactions. CONCLUSIONS: Rectal indomethacin before ERCP decreases the risk of hyperamylasemia and pancreatitis. Indomethacine is a feasible, low-cost drug with minimal or nil side effects.

Efecto de la administración de indometacina rectal sobre los niveles séricos de amilasa posteriores a colangiopancreatografía retrógrada endoscópica y su impacto en la aparición de episodios de pancreatitis secundaria / Effect of the rectal administration of indomethacin on amylase serum levels after endoscopic retrograde cholangiopancreatography, and its impact on the development of secondary pancreatitis episodes

Introducción: hiperamilasemia y pancreatitis aguda representan las complicaciones mayores más frecuentes posteriores a colangiopancreatografía retrógrada endoscópica (CPRE), apareciendo en 1-30% de los casos. Objetivo: determinar la incidencia de hiperamilasemia y pancreatitis posterior a CPRE y evaluar la utilidad de indometacina rectal para la prevención de estos. Material y métodos: ensayo clínico controlado. Durante un periodo de 12 meses se incluyeron 150 pacientes. Estos fueron divididos en grupo de estudio (n = 75), a quienes se administró indometacina rectal 100 mg 2 horas previas al procedimiento, y control (n = 75) que recibió glicerina. Dos horas posteriores a la CPRE se determinó el nivel de amilasa sérica y se clasificaron en: 0 = 600 UI/l. Los episodios de pancreatitis clínica se cuantificaron y clasificaron de acuerdo a los criterios de Ranson. Resultados: distribución por género: 100 mujeres y 50 hombres. Edad media: 55,37 ± 18,0 para el grupo de estudio y 51,1 ± 17,0 para el control. El diagnóstico de patología benigna se presentó en 56 (74,7%) casos del grupo de estudio y 59 (78,7%) del control. Posterior al procedimiento, 13 (17,3%) pacientes del grupo experimental y 28 (37,3%) del control desarrollaron hiperamilasemia (p 600 UI/l en 3 pacientes del grupo de estudio y 10 del control (p = 0,001). Se detectó pancreatitis leve en 5,3% de los pacientes del grupo de estudio y 16% del control (p < 0,05). No hubo mortalidad ni eventos adversos. Conclusiones: indometacina rectal previo a CPRE disminuye el riesgo de hiperamilasemia y pancreatitis. La indometacina es accesible, de bajo costo con mínimos o nulos efectos secundarios

Background: hyperamylasemia and acute pancreatitis represent the most frequent major complication after endoscopic retrograde cholangiopancreatography (ERCP), developing in 1-30% of cases. Objective: to determine the incidence of hyperamylasemia and acute pancreatitis after ERCP, and to assess the utility of rectal indomethacin to prevent these events. Material and methods: a randomized clinical trial. During a 12-month period 150 patients were included. They were divided up into a study group (n = 75), where 100 mg of rectal indomethacin were administered 2 hours prior to the procedure, and a control group (n = 75), which received rectal glycerin. Two hours after ERCP serum amylase levels were measured and classified as follows: 0 = 600 IU/L. Clinical pancreatitis episodes were quantified and classified according to Ranson’s criteria. Results: gender distribution: 100 women and 50 men. Mean age: 55.37 ± 18.0 for the study group, and 51.1 ± 17.0 for the control group. A diagnosis of benign pathology was present in 56 (74.7%) cases in the study group, and 59 (78.7%) controls. After ERCP 13 (17.3%) patients in the study group and 28 (37.3%) in the control group developed hyperamylasemia (p 600 IU/L was found in 3 patients in the study group, and in 10 in the control group (p = 0.001). Mild pancreatitis was detected in 4 (5.3%) patients in the study group, and in 12 (16%) patients in the control group (p = 0.034). There were no deaths or adverse drug reactions. Conclusions: rectal indomethacin before ERCP decreases the risk of hyperamylasemia and pancreatitis. Indomethacine is a feasible, low-cost drug with minimal or nil side effects

Vaginal bleeding patterns in users of Perlutal, a once-a-month injectable contraceptive consisting of 10 mg estradiol enanthate combined with 150 mg dihydroxyprogesterone acetophenide. A trial of 5462 woman-months.

Perlutal (other names: Topasel, Perlutan) is a once-a-month injectable contraceptive that contains 10 mg estradiol enanthate and 150 mg dihydroxyprogesterone acetophenide. A prospective trial was conducted in 216 women in Medellín, Colombia, over five years (5,462 woman-months) to establish the rates of the different vaginal bleeding patterns during the use of Perlutal, and to assess their relation with discontinuation of the Perlutal regimen. It was found that with the use of Perlutal, the duration of menstrual bleeding decreased from 3.9 to 2.7 days (p < 0.01), and that the incidence of dysmenorrhea decreased from 31% to 1.6% (p < 0.01). At one year of follow-up, the incidence of altered bleeding patterns was 5.1%. The discontinuation rate due to an altered bleeding pattern was 3.9%. It is concluded that the low incidence of altered bleeding patterns observed with the use of Perlutal leads to a low discontinuation rate among users.

Timing of mating and ovarian response in llamas (Lama glama) treated with pFSH.

The effect of the timing of mating on ovarian response in llamas was evaluated using 20 adult llamas weighing 90-120 kg which had been in oestrus for 5 days and were treated with 20 mg pFSH every 12 h for the following 5 days (total dose: 200 mg of FSH-NIH-P1). They were randomly allocated to Group A (N = 10) and mated immediately at the end of pFSH treatment or to Group B (n = 10) and mated 36 h after the end of pFSH treatment. Llamas of both groups were given hCG (750 iu, i.m.) immediately after mating. A second mating was allowed 12 h later. Ova and embryos were recovered by non-surgical uterine flushing 7 days after the first mating. Ovarian response was immediately evaluated afterwards via laparoscopy. The mean ovulation rate of 4.5 corpora lutea for Group A was significantly lower (P < 0.01) than the mean of 13.8 observed for Group B. The total ovarian response (number of corpora lutea + follicles > 10 mm) was also significantly higher (P < 0.01) in Group B than in Group A. Twenty-seven ova were recovered in each group, corresponding to 60% and 20% (P < 0.01) of the corpora lutea observed in Groups A and B, respectively; however, no significant difference (P > 0.05) in fertilisation rate was observed. The results show that pFSH induces superovulation in llamas treated during oestrus and that a 36-h interval between the end of FSH treatment and mating increases ovulation rate and the total ovarian response but does not affect the number of ova/embryos recovered.

Superovulation in llamas (Lama glama) with pFSH and equine chorionic gonadotrophin used individually or in combination.

The purpose of this experiment was to evaluate the efficacy of pFSH and/or equine chorionic gonadotrophin (eCG) for inducing superovulation in llamas. Sixteen adult llamas weighing on average 130 kg (range 110-140) and which had been showing signs of oestrus for 5 days were randomly allocated to three treatment groups and one control group (n = 4). Llamas in Group A received eCG (500 IU, i.m.) once daily for 3 days, those in Group B received pFSH i.m., in decreasing doses every 12 h for 5 days for a total of 220 mg, while those in Group C received eCG (500 IU, i.m.) once, and pFSH (total of 156 mg, i.m.) in decreasing doses for the next 4 days. Llamas in Group D (control) received saline (5 ml, i.m.) every 12 h for 5 days. All llamas were allowed to be mated on the evening of Day 5 and were given hCG (750 IU, i.m.) at that time; a second mating was carried out 12 h later. A non-surgical ova/embryo collection technique was performed 7 days after the first mating and then the ovarian response was evaluated by way of laparoscopy. All 16 llamas were mated successfully. The mean (SEM) number of ovulations (7.3 +/- 3.1) in Group B was significantly higher (P < 0.05) than in the other groups (1.5 +/- 0.5, 2.0 +/- 0.7, and 0.3 +/- 0.3 for groups A, C and D, respectively). The number of follicles > 10 mm at the time of ova/embryo collection was significantly higher (P < 0.05) in the groups treated with eCG. A total of 21 ova/embryos was recovered from the all flushed llamas, corresponding to 47.7% of corpora lutea observed. Of the 21 ova, 15 were fertilised; 13 of those were classified as excellent blastocysts and the remaining 2 were classified as dead or degenerating. Results demonstrate that llamas can be successfully ovarian superstimulated while expressing behavioural oestrus and suggest that pFSH is more effective than eCG to induce superovulation.