Reproduction

  • Alpaca Breeding - A Reference

    It is widely known and accepted that the simple act of breeding can have a major impact to an alpaca female uterus. Generally, it repairs itself after a period of time, 7-20 days. The uterus requires a certain amount of time to heal itself after a birth and regain a normal non-pregnant shape. This is the reason why you wait for nearly three weeks before rebreeding*. Studies have shown that this is common in open alpaca ranges of Peru. Repeatable breedings at short intervals or unnecessary breedings can do irreparable damage to a female. This action has the effect of shortening the breeding life of a female. The idea here is to breed females keeping the damage to her uterus minimal. To do this requires a good understanding of a female’s cycle and her receptiveness to a male.More »
  • Alpaca Semen Characteristics Previous to a Mating Period

    Increasing the knowledge of the semen characteristics in the alpaca will contribute to understanding one of the many factors that affect the poor fertility rate in this species. Ten adult male alpacas, 2.6–10 years of age, average weight 64.7±4.7 kg were used. The animals were distributed randomly into two groups of five each and submitted alternatively to two semen collections, using an artificial vagina and sexually receptive females. For the first semen collection the animals had a sexual rest period of about 90 and 45 days before the second. Duration of semen collection, color and volume of ejaculate were recorded, and sperm concentration and morphology (light microscopy) were evaluated. Descriptive statistical analyses were used for each variable, considering all samples obtained (n=19). An analysis of variance for animal groups and opportunity of collection were used for quantitative variables. Most frequent color was opalescent white (84.2%). There were no statistical differences among male groups or between semen collections. The average values and standard deviations for the quantitative variables were: 12.3±7.2 min for semen collection time, 1.8±0.8 ml for ejaculate volume, (17.6±26.1)×106 sperm/ml for sperm concentration and 34.0±52.2×106 for total number of sperm per ejaculate. The percentage of normal spermatozoa was 51.0±12.4%. From the total abnormalities, that of mid piece segment (14.4%) was the most frequent. These results indicate that male alpaca have poor semen quality, when compared with other domestic species. Nevertheless, for the evaluation of male alpaca as breeders it would be necessary to create a protocol for the selection of them, where phenotypic, behavioral and seminogram aspects are considered. The values reported herein define the characteristics of the alpaca semen that could be considered as the initial base of the seminal analysis to select male alpacas before mating.More »
  • Bilateral Epidiymal Cysts in an Alpaca Male Used for Breeding

    A 4-year-old alpaca stud was presented for examination of his reproductive tract. Ultrasonographic examination of the gonads revealed 2 cystic structures associated with the head of each epididymis. Biopsies of each testicle evidenced mild testicular degeneration. Histopathologic examination of the gonads revealed cystic efferent ductules in the head of each epididymis.More »
  • Biochemical Isolation and Purification of Ovulation-Inducing Factor (OIF) in Seminal Plasma of Llamas

    The objective of the present study was to isolate and purify the protein fraction(s) of llama seminal plasma responsible for the ovulation-inducing effect of the ejaculate.More »
  • Cetrorelix Suppresses the Preovulatory LH Surge and Ovulation Induced by Ovulation-Inducing Factor (OIF) Present in Llama Seminal Plasma

    The purpose of the study was to determine if the effect of llama OIF on LH secretion is mediated by stimulation of the hypothalamus or pituitary gland.More »
  • Do Differences in Maternal Immunoglobulin G Influence Passive Transfer and Subsequent Cria Growth in Alpacas?

    Undetected failure of passive transfer (FPT) of immunoglobulin is a major determinant of mortality in newborn alpaca cria, and early detection with proactive management can reduce mortality rates in cases of suspect FPT. The goal of this prospective observational study was to evaluate maternal serum IgG levels as a predictor for subsequent cria FPT (IgG 2000 mg/dl (n = 13). Analysis of variance within maternal groups revealed significant differences in cria birth IgG levels, whereby the highest levels were observed when dam IgG measured 1000-1499 mg/dl, followed by 1500-2000 mg/dl and cria had the lowest birth IgG levels from dams exhibiting IgG levels > 2000 mg/dl (640 mg/dl, 554 mg/dl and 545 mg/dl respectively). Although there were cria with birth IgGMore »
  • Embryonic Mortality in the Alpaca

    Four groups of 20 females each were sacrificed on days 3, 28–31, 40–55, or 87–95 following mating, to determine the fertility rates and the extent and time of embryonic losses. In a second experiment each of 21 adult and 20 yearling virgin females were mated to intact males, with or without single intramuscular doses of 300 IU of HCG given 2 hr before mating. Ovulation and fertilization rates on day 3 were determined in a representative half of the animals at sacrifice, or laparotomy, and in the other half maintenance of pregnancy was tested at monthly intervals. Fertility rates declined from 70% on day 3 to 35% on days 28–31 and showed little change thereafter. Although both ovaries were equally active, significantly more pregnancies were found in the left horns by days 87–95. Migrations of embryos from right to left uterine horns were found in three cases suggesting that the right uterine horn provides a less suitable environment for the embryo. Maintenance of pregnancies through day 90 in the second experiment was significantly higher (p < 0.05) in females treated with HCG before mating. No pregnancies were maintained in control animals up to this stage. Plasma progesterone levels at day 30 were higher and 20α-ol levels lower than in the natural service animals, suggesting a decreased conversion of progesterone to 20α-ol in the HCG-treated animals. Ovulation and fertilization rates in yearlings were similar to adults, but pregnancy rate on day 30 was significantly higher (p < 0.05) in yearlings.More »
  • Evaluation of Early Reproductive Performance in the Postpartum Alpaca by Progesterone Concentrations

    The proportion of female alpacas ovulating, conceiving and remaining pregnant up to 40 days after copulation was evaluated using progesterone concentrations. One hundred and seventy six parous, postpartum alpacas were divided into three groups for breeding at 10, 20, and 30 days postpartum at the La Raya research station, Cusco, Peru. Females were further subdivided into three groups to allow copulation once, twice, or three times at 24-h intervals, within different postpartum times. Blood samples were collected at time of breeding, at Day 7 (ovulation), at Day 21 (conception), and Day 40 (pregnancy) from all females after breeding. Progesterone analysis was performed by enzyme immunoassay. There was significant difference in the proportion of females ovulating at Days 10 (), 20 () or 30 () postpartum; however, frequency of breeding did not increase the number of females ovulating. There was significant difference in the proportion of females conceiving at Days 10 (), 20 (), and 30 () postpartum, compared with females ovulating at the three times of breeding. There was also a significant difference in the number of females in which pregnancy was sustained at Day 40 when bred at 10 (19), 20 (31) and 30 (44) days postpartum. There were significant differences in the concentration of progesterone of ovulating females (4.2 ng ml−1), conceiving females (3.1 ng ml−1) and females remaining pregnant (1.4 ng ml−1), compared with the overall mean of 0.4 ng ml−1 for females that did not ovulate, did not conceive and that experienced embryonic mortality. Altogether, these results suggest that breeding as early as Day 10 postpartum does not yield acceptable fertility rates as compared with breeding on Days 20 or 30 postpartum, and that repeated breeding does not increase the number of females ovulating or conceiving.More »
  • Foetal Mortality at Different Stages of Gestation in Alpacas (Lama pacos) and the Associated Changes in Progesterone Concentrations

    From spring 1990 to autumn 1993, 44 spring-mated and 82 autumn-mated alpacas at Flock House Agricultural Centre (FH) had their pregnancies monitored by ultrasound every 10–14 days from day 20 to day 120 of gestation. A further 32 autumn-mated alpacas at Tara Hills High Country Research Station (TH) were monitored in 1992. Trans-rectal probes were used in early gestation and trans-abdominal probes in late gestation. As techniques for pregnancy diagnosis in alpacas improved during the experiment, the stage of gestation at which pregnancies were first confirmed became earlier. From spring 1991 onwards most pregnancies were first diagnosed at 20–30 days of gestation. Progesterone concentrations were determined from individual blood samples collected each time alpacas were brought in for pregnancy diagnosis from spring 1991 onwards. Foetal loss from day 30 onwards was 25.7% with the foetal losses after day 120 of gestation being 9.6–16.7% in different mating groups. There were apparent differences in the pattern of foetal loss between autumn- and spring-mated alpacas at FH with foetal losses before day 81 being 17.3% and 2.8% respectively and no significant difference in foetal loss after day 81 of gestation. The younger New Zealand born alpacas had a similar incidence of foetal loss to the older Chilean born alpacas. There was a suggestion at TH that the stress of transport and relocation of a group of alpacas at 212 ± 3 days of gestation precipitated a high incidence of foetal loss. The spring-mated alpacas had a longer gestation length (350.1 ± 2.7 days) than autumn-mated alpacas at FH (340.2 ± 1.9 days).More »
  • Infertility and Subfertility in the Female Camelid

    Poor reproductive efficiency has been described as one of the major problems in camelids. The mean annual fertility (birthing rate) in alpacas and llamas in South America can be as low as 45%. No studies exist on the actual annual pregnancy rates in alpacas on North American ranches. Informal surveys in our area of practice (Pacific Northwestern USA) show an annual birthing rate of 78%. Various congenital as well as acquired disorders of the reproductive tract in camelids have been described and may play an important role in reduced fertility.1 In many cases, diagnosis of the cause of infertility may require monitoring the female over at least one reproductive cycle (from follicular growth to mating and pregnancy diagnosis). The objectives would be to answer the following questions: What is the expertise of the breeder? Is the male fertile? Does the female have normal genitalia? Is the female ovulating? Judicious choice of examination techniques and interpretation allow reaching a diagnosis in an accurate and timely manner. The objective of the present chapter is to discuss the major presenting complaints with regard to camelid infertility as seen in practice, as well as the main reproductive disorders in the female camelid and the approach to diagnosis and treatment.More »
  • Paddock Mating of Alpacas

    A step-by-step introduction to one-on-one hand matings of alpacas.More »
  • Reproduction in South American Camelids

    In this article, you are about to see that the South American Camelids appear to be a physiological and anatomical blend between cattle, horses, pigs and cats! I will point out these similarities as the article progresses.More »
  • Reproductive Anatomy and Physiology in the Male

    The male camelid has a tremendous impact on the reproductive performance and genetic improvement of a herd. Despite this, scientific reports on the male in the published literature remain scarce. Approximately only one paper is published on the male for every six papers published on reproduction in the female. In recent years, interest in the male has increased, particularly in semen and its use for artificial insemination. This chapter covers the reproductive physiology of the male with regard to the development of testicles, the disappearance of the penis–prepuce attachment, and the concentrations of testosterone. Finally, the spermatogenic function of testicles, including spermatic reserves, and the relationship between semen characteristics and fertility of the female are reviewed.More »
  • Reproductive Physiology in Alpacas

    A look at the basic fundamentals of the physiology of reproduction in alpacas.More »
  • Studies on the Physiology of Early Pregnancy in Alpacas

    Camelids are economically important production animals in many areas of the world. Early pregnancy loss is a major cause of reproductive inefficiency. Pregnancy maintenance depends on a timely signaling mechanism called maternal recognition of pregnancy (MRP). This mechanism is not well characterized in camelids. The work presented in this thesis is part of a larger research program to study early embryo development and MRP, as well as factors involved in early pregnancy loss.More »
  • Supervised Yard Mating of Alpacas

    A step-by-step introduction to one-on-one hand matings of alpacas.More »
  • The Effect of Enzymes on Semen Viscosity in Llamas and Alpacas

    The effect of four enzymes: collagenase, fibrinolysin, hyalurodinase, and trypsin were recorded on the viscosity, motility,percent live spermatozoa and acrosome integrity of Llama and Alpaca semen. Semen samples were collected using a modified artificial vagina for each of the five llamas and five alpacas. A 25% solution of the of enzyme at a concentration of 1 mg/ml was added to the ejaculate. Analysis of variance was used to determine differences in eliminating viscosity and alterations in motility, percent live spermatozoa and the acrosomal integrity at 0 (time of semen collection), 2 and 5 min. In Llama and Alpaca semen, collagenase eliminated viscosity in 100 and 99% of the samples, respectively. Correspondingly, fibrinolysin in 89 and 59%; hyalurodinase in 88 and 36%; and trypsin in 55 and 68% of the samples (pMore »
  • The Nerve of Ovulation-Inducing Factor in Semen

    A component in seminal fluid elicits an ovulatory response and has been discovered in every species examined thus far. The existence of an ovulation-inducing factor (OIF) in seminal plasma has broad implications and evokes questions about identity, tissue sources, mechanism of action, role among species, and clinical relevance in infertility. Most of these questions remain unanswered. The goal of this study was to determine the identity of OIF in support of the hypothesis that it is a single distinct and widely conserved entity. Seminal plasma from llamas and bulls was used as representative of induced and spontaneous ovulators, respectively. A fraction isolated from llama seminal plasma by column chromatography was identified as OIF by eliciting luteinizing hormone (LH) release and ovulation in llamas. MALDI-TOF revealed a molecular mass of 13,221 Da, and 12–23 aa sequences of OIF had homology with human, porcine, bovine, and murine sequences of β nerve growth factor (β-NGF). X-ray diffraction data were used to solve the full sequence and structure of OIF as β-NGF. Neurite development and up-regulation of trkA in phaeochromocytoma (PC12) cells in vitro confirmed NGF-like properties of OIF. Western blot analysis of llama and bull seminal plasma confirmed immunorecognition of OIF using polyclonal mouse anti-NGF, and administration of β-NGF from mouse submandibular glands induced ovulation in llamas. We conclude that OIF in seminal plasma is β-NGF and that it is highly conserved. An endocrine route of action of NGF elucidates a previously unknown pathway for the direct influence of the male on the hypothalamo–pituitary–gonadal axis of the inseminated female.More »

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