Astrid Vargas

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short title: lynx and cat relaxin and RXFP1 expression

Argumentación, discurso y política

El presente articulo contiene una reflexion en torno a un concepto fundamental: la argumentacion,... more El presente articulo contiene una reflexion en torno a un concepto fundamental: la argumentacion, realizando un abordaje del mismo a partir de algunos de sus elementos constituyentes, lo cual permite al lector unamayor comprension acerca de la dinamica social-cultural vista desde el analisis del discurso y mas especificamente los elementos que componen el discurso politico, que a su vez contribuye con el control de las masas y en ocasiones, hace uso del miedo como medio de persuasion.

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Benign juvenile focal epilepsy in a captive Iberian lynx (Lynx pardinus)

Veterinary Record Case Reports, 2019

An 8-week-old intact male lynx cub (Lynx pardinus) from a captive breeding colony was presented w... more An 8-week-old intact male lynx cub (Lynx pardinus) from a captive breeding colony was presented with a 2-day history of cluster seizures. There was no history of intoxication. Physical and neurological examinations were normal. Complete blood profile, infectious diseases panel, MRI of the brain and cerebrospinal fluid analysis were unremarkable. A diagnosis of suspected idiopathic epilepsy was made. The lynx cub was treated with increasing doses of phenobarbital and seizure activity stopped within 28 days. After 23 seizure-free months, phenobarbital was tapered over 4 months and finally discontinued. No further seizures were observed during the follow-up period of 8 years. Given the early onset followed by rapid and maintained remission, seizure semiology and the lack of underlying disease, a presumptive diagnosis of benign focal epilepsy similar to benign childhood focal epilepsies as described in human medicine is postulated.

Programa de Funcionamiento del centro de cría El Acebuche, Parque Nacional Doñana

Comparative analysis of intraluteal steroidogenic enzymes emphasises the functionality of fresh and persistent corpora lutea during pro- and metoestrus in the lynx

The Journal of Steroid Biochemistry and Molecular Biology, 2015

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A feline leukemia virus (FeLV) outbreak in the Doñana Iberian lynx population

The Feline Leukemia Virus (FeLV) is a retrovirus that affects domestic cats all over the world, o... more The Feline Leukemia Virus (FeLV) is a retrovirus that affects domestic cats all over the world, occasionally affecting other felid species. Its pathogenic effects generally include anemia, immunosuppression and tumors. In the Iberian lynx (Lynx pardinus), sporadic contact has been detected since the virus began to be monitored in the population, although no outbreak had ever been detected before 2007. During the first half of 2007, an FeLV outbreak was detected in Coto del Rey, the densest subpopulation within the Donana Iberian lynx population. The outbreak showed a rapid dissemination, 66% of the individuals in the nucleus being infected during the first trimester of the year. The infection showed an acute response and high associated mortality. Given that the occurrence of the outbreak threatened the scarce Donana Iberian lynx population, a management programme was carried out to stop the dispersion of the virus over the population. The management measures included in the control programme included the following: 1) removal of viremic lynxes; 2) vaccination of negative individuals and 3) reduction of the feral cat population (which is thought to be the primary vector for the FeLV infection in lynxes). Around 80% of the total lynx population and 90% of the outbreak focus subpopulation could be evaluated. Finally, the outbreak could be controlled during 2007, probably due to the application of the management measures. A total of 12 infected individuals were found, most of them showing signs of nonregenerating anemia and associated immunosuppression. Two of them sequestered the virus and live normally in the field, while eight of them have died.

Pregnancy diagnosis in urine of Iberian lynx (Lynx pardinus)

Theriogenology, Jan 15, 2009

Diagnosis of pregnancies is an important management tool for the Iberian lynx Conservation Breedi... more Diagnosis of pregnancies is an important management tool for the Iberian lynx Conservation Breeding Program, a program geared to recover the world's most endangered felid. Non-invasive methods such as fecal hormone analyses are not applicable to the lynx, since fecal progestin does not follow the typical pregnancy pattern of felids. Therefore, we aimed to test whether urine can be used as an alternative substance for pregnancy diagnosis in the Iberian lynx. Progesterone immunoreactive metabolites were determined in urine samples of pregnant and non-pregnant females before and during breeding season. Additionally, we used the Witness Relaxin test to determine relaxin in blood and urine. No differences were found in progestin concentrations determined in urine samples collected from pregnant and non-pregnant animals between day 1 and 65 following mating. Although the Witness Relaxin test was positive in serum samples collected from animals between day 32 and 56 of pregnancy, it fa...

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Early development and growth in captive-born Iberian lynx ( Lynx pardinus )

Zoo Biology, 2014

Knowledge on the growth and early development patterns of endangered species can become a useful ... more Knowledge on the growth and early development patterns of endangered species can become a useful conservation tool because it may allow detecting anomalous growth in newborns, both in captivity breeding and in the wild. We studied the growth and early development of 40 Iberian lynx (Lynx pardinus) cubs belonging to 21 litters born in captivity between 2005 and 2012 at &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;El Acebuche&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; Iberian Lynx Breeding Centre. This is the first study on growth in this critically endangered species. The Iberian lynx cubs were not fully developed at birth. During the first 3 weeks of life, cubs underwent many of the physical changes that allowed them to improve their interaction with the environment, such as the opening of eye and auditory channels, teeth eruptions, and the ability to walk. When the cubs were 1 month old, they were ready to leave the den and develop new behaviors such as the exploration of their environment, play, or hunt. Three different models had been fitted to the body mass growth of the Iberian lynx. The von Bertalanffy curve provided the best fit. The asymptotic adult mass was the only parameter that differed between males and females (males being 8% larger), due to the higher growth rate of males. The adult weight of hand-reared cubs (i.e., those abandoned at born) did not differ from that of cubs reared by their mothers. Both growth and development showed differences from other lynx species.

Effects of diet on captive black‐footed ferret (Mustela nigripes) food preference

Zoo Biology, 1996

Black-footed ferrets (Mustela nigripes) are both habitat and prey specialists that depend on prai... more

Reproductive inefficiency in male black-footed ferrets (Mustela nigripes)

Zoo Biology, 2000

The black-footed ferret (Mustela nigripes), once considered extinct, has benefited from captive b... more The black-footed ferret (Mustela nigripes), once considered extinct, has benefited from captive breeding and subsequent reintroduction into native habitat. A high proportion of females (&gt;90%) exhibit estrus in captivity during the spring breeding season. However, many males considered to be prime-breeding age (1-3 years old) fail to sire offspring. Breeding records in 1995 revealed that 40 of 73 males (55%) managed under the Black-Footed Ferret Species Survival Plan did not reproduce, despite being provided opportunity. The present study was conducted to determine the incidence and etiology of male reproductive failure in 1996 and 1997. In 1996, 38 of 69 (55%) 1- to 3-year-old males failed to sire offspring. Likewise, 35 of 60 (58%) males did not reproduce in 1997. Overall, 21% of adult males failed to sire young in three consecutive breeding seasons (1995-1997). Electroejaculate traits (ejaculate volume, sperm concentration, motility, morphology, and acrosomal integrity) from 29 proven breeder males were not different (P &gt; 0.05) from those of 23 males that did not sire young (nonproven breeders). However, six categories of reproductive failure were identified for the 73 prime-breeding age, nonproven males: 1) underdeveloped testes (22%); 2) improper breeding position with the female (25%); 3) excessive aggression toward estrous females (9%); 4) copulation with no sperm detected at postcoital lavage (19%); 5) copulation with sperm in the vaginal lavage but no resulting pregnancy (18%); and 6) copulation with no vaginal lavage performed and no resulting pregnancy (7%). These data indicate that combined behavioral and physiologic factors, but not overall sperm quality, influence reproductive performance in male black-footed ferrets managed in captivity. Zoo Biol 19:517-528, 2000. Copyright 2000 Wiley-Liss, Inc.

Importance of canine distemper virus (CDV) infection in free-ranging Iberian lynxes (Lynx pardinus)

Veterinary Microbiology, 2010

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Feline leukemia virus infection: A threat for the survival of the critically endangered Iberian lynx (Lynx pardinus)

Veterinary Immunology and Immunopathology, 2010

The Iberian lynx (Lynx pardinus) is native to the Iberian peninsula and is considered the most en... more The Iberian lynx (Lynx pardinus) is native to the Iberian peninsula and is considered the most endangered felid species in the world (Nowell and Jackson, 1996; Nowell, 2002; IUCN, 2007). Only two isolated populations live in southern Spain (Doñ ana and Sierra Morena areas), where only 40-50 and 150-200 individuals, respectively, are estimated to remain (Ferreras et al., 2010). During the last decades, this species has been especially threatened due to the decline of its basic prey (the wild European rabbit, Oryctolagus cuniculus), fragmentation and loss of habitat, and non-natural mortality due to illegal hunting and road kills (Ferreras et al., 2010). In addition, a phylogenetic study has recently documented the limited genetic diversity of the Iberian lynx population (Johnson et al., 2004), and histopathological studies revealed generalized immune depletion in these animals, apparently unrelated to infectious agents or malnutrition (Peñ a et al., 2006). Low population size, coupled with the low genetic variability, may contribute to render this species particularly susceptible to infectious diseases. Although limited, information is available on the incidence of Cytauxzoon felis (C. felis, a Theileria-like agent), Toxoplasma gondii, hemotropic mycoplasmas, Mycobacterium bovis, Ehrlichia and Anaplasma species, Bartonella henselae,

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Reproductive traits in captive and free-ranging males of the critically endangered Iberian lynx (Lynx pardinus)

REPRODUCTION, 2009

The Iberian lynx (Lynx pardinus) is the most endangered felid in the world. Adequate genetic mana... more The Iberian lynx (Lynx pardinus) is the most endangered felid in the world. Adequate genetic management of in situ and ex situ populations, and linkage between both, require knowledge on male reproductive biology and factors influencing it. We examined the influence of age, free-ranging versus captive conditions and seasonality on phenotypic, endocrine and semen traits, and links between reproductive traits and male fertility. Males had relatively small testes, produced low sperm numbers, a low proportion of normal sperm, and a high proportion of motile sperm. Young (2-year-old) males had lower testosterone levels, fewer sperm, and a lower proportion of motile and normal sperm than ≥4-year-old males. No major differences were found in semen traits before and after the mating season or between free-ranging and captive males, although the latter had better sperm motility. Males with larger relative testes weight and more sperm copulated more frequently, whereas males that produced mor...

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The molecular detection of relaxin and its receptor RXFP1 in reproductive tissue of Felis catus and Lynx pardinus during pregnancy

REPRODUCTION, 2012

Relaxin acts as a pregnancy-specific signal in feline species, but specific information about pro... more Relaxin acts as a pregnancy-specific signal in feline species, but specific information about protein structure and binding is essential for the improvement of pregnancy diagnosis in endangered feline species, like the Iberian lynx. To generate a felid-specific relaxin antibody, the DNA and protein sequences of lynx and cat were determined and peptides were chosen for antibody generation. In addition, relaxin and relaxin receptor (RXFP1) mRNA expressions were measured in uteri and ovaries of pregnant domestic cats and lynx placentae. Using real-time PCR and immunohistochemistry, it was established that feline placenta is the main source of relaxin during pregnancy. In other tested tissues, relaxin mRNA expression was weak. TheRXFP1mRNA expression was found mainly in cat uterine tissue and feline placentae. It was assumed that these tissues were main targets for relaxin. In the ovary, relaxin immunostaining was associated with blood vessels, signifying its role in vascularization.

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Ketamine-Medetomidine or Isoflurane Immobilization of Black-Footed Ferrets

The Journal of Wildlife Management, 1998

Field immobilization of black-footed ferrets (Mustela nigripes) is required for examination, iden... more

Development of survival skills in captive-raised Siberian polecats (Mustela eversmanni) I: Locating prey

Journal of Ethology, 1990

Abstract -- We exposed naive Siberain polecats (Mustela eversmanni) (aged 2, 3, and 4 months) to ... more

Determination of serum biochemical reference intervals for the Iberian lynx (Lynx pardinus)

Veterinary journal (London, England : 1997), 2010

Biochemical reference intervals were determined for 31 clinically healthy Iberian lynxes (Lynx pa... more Biochemical reference intervals were determined for 31 clinically healthy Iberian lynxes (Lynx pardinus) between 1 and 6 years of age. Thirteen of the lynxes were wild-caught and the other 18 were captive-reared animals. The samples were collected between November 2004 and December 2006. The influence of sex (males vs. females), age (juveniles vs. adults) and habitat condition (free-living vs. captive) on the biochemical analytes were evaluated. Serum albumin concentrations were significantly higher in females than in males, while creatine phosphokinase was higher in males. The levels of alkaline phosphatase and lactate dehydrogenase were higher in juvenile lynxes, while gamma glutamyl-transferase and creatinine values were higher in adults. Lynxes captured in the wild had higher concentrations of iron, calcium, alkaline phosphatase and creatinine, but lower aspartate aminotransferase and alanine aminotransferase than lynxes maintained in captivity. The results were generally compar...

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Feline leukemia virus and other pathogens as important threats to the survival of the critically endangered Iberian lynx (Lynx pardinus)

PloS one, 2009

BACKGROUND: The Iberian lynx (Lynx pardinus) is considered the most endangered felid species in t... more BACKGROUND: The Iberian lynx (Lynx pardinus) is considered the most endangered felid species in the world. In order to save this species, the Spanish authorities implemented a captive breeding program recruiting lynxes from the wild. In this context, a retrospective survey on prevalence of selected feline pathogens in free-ranging lynxes was initiated. METHODOLOGY/ PRINCIPAL FINDINGS: We systematically analyzed the prevalence and importance of seven viral, one protozoan (Cytauxzoon felis), and several bacterial (e.g., hemotropic mycoplasma) infections in 77 of approximately 200 remaining free-ranging Iberian lynxes of the Doñana and Sierra Morena areas, in Southern Spain, between 2003 and 2007. With the exception of feline immunodeficiency virus (FIV), evidence of infection by all tested feline pathogens was found in Iberian lynxes. Fourteen lynxes were feline leukemia virus (FeLV) provirus-positive; eleven of these were antigenemic (FeLV p27 positive). All 14 animals tested negativ...

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Conservación Ex Situ Del Lince Ibérico: Un Enfoque Multidisciplinar Iberian Lynx Ex Situ Conservation: An Interdisciplinary …

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Heterozygosity‐Fitness Correlations and Inbreeding Depression in Two Critically Endangered Mammals

Conservation Biology, 2012

The relation among inbreeding, heterozygosity, and fitness has been studied primarily among outbr... more The relation among inbreeding, heterozygosity, and fitness has been studied primarily among outbred populations, and little is known about these phenomena in endangered populations. Most researchers conclude that the relation between coefficient of inbreeding estimated from pedigrees and fitness traits (inbreeding-fitness correlations) better reflects inbreeding depression than the relation between marker heterozygosity and fitness traits (heterozygosity-fitness correlations). However, it has been suggested recently that heterozygosity-fitness correlations should only be expected when inbreeding generates extensive identity disequilibrium (correlations in heterozygosity and homozygosity across loci throughout the genome). We tested this hypothesis in Mohor gazelle (Gazella dama mhorr) and Iberian lynx (Lynx pardinus). For Mohor gazelle, we calculated the inbreeding coefficient and measured heterozygosity at 17 microsatellite loci. For Iberian lynx, we measured heterozygosity at 36 microsatellite loci. In both species we estimated semen quality, a phenotypic trait directly related to fitness that is controlled by many loci and is affected by inbreeding depression. Both species showed evidence of extensive identity disequilibrium, and in both species heterozygosity was associated with semen quality. In the Iberian lynx the low proportion of normal sperm associated with low levels of heterozygosity was so extreme that it is likely to limit the fertility of males. In Mohor gazelle, although heterozygosity was associated with semen quality, inbreeding coefficient was not. This result suggests that when coefficient of inbreeding is calculated on the basis of a genealogy that begins after a long history of inbreeding, the coefficient of inbreeding fails to capture previous demographic information because it is a poor estimator of accumulated individual inbreeding. We conclude that among highly endangered species with extensive identity disequilibrium, examination of heterozygosity-fitness correlations may be an effective way to detect inbreeding depression, whereas inbreeding-fitness correlations may be poor indicators of inbreeding depression if the pedigree does not accurately reflect the history of inbreeding.

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