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During the past decade the need for Artificial Reproductive Techniques in felids has greatly increased. Mostly, this is a result of growing expectations that these techniques may be applied in conservation biology and thereby contribute to saving wild felids from extinction. In this article we describe three most common methods of obtaining embryos in vitro in the domestic cat and its wild relatives: classic in vitro fertilisation, in vitro fertilisation by intracytoplasmic sperm injection and somatic cell nuclear transfer. Each of the methods provides a cleavage rate of around 50% and approx. 20% of embryos develop to the blastocyst stage. After the transfer of embryos produced by these methods, scientists obtained living offspring of the domestic cat, as well as several wild cats: the tiger, serval, fishing cat, caracal, ocelot, wild cat, sand cat, black-footed cat and the oncilla. These successes, in spite of the low efficiency of the discussed methods, are promising and suggest that biotechniques of reproduction will be valuable tools in the protection of wild species. Somatic cell nuclear transfer will allow to sustain the narrow gene pool in the critically endangered felids. For these reasons it is necessary to conduct further research on the optimization of artificial reproduction techniques in cats.
The use of assisted reproductive techniques in wild felids (Felidae) is currently the subject of research in many scientific centers all around the world. Despite the described success, the pregnancy rates obtained as the result of artificial insemination or embryo transfer are low and the litters are small, which is a limiting factor for wider use of reproduction biotechnology in wild felids. The lack of sufficient knowledge about endocrinology of individual members of the Felidae family and the inability to optimize female hormonal stimulation is given as a reason of failure by many authors. This paper presents methods of control of ovarian cycle in wild animals, characteristic features of reproduction of the family Felidae, and methods of the induction of estrus and ovulation. The paper also draws attention to endocrine disorders that occur in felines after hormonal stimulation and describes attempts to minimize them by prestimulatory down-regulation of ovarian activity.
The lowest part of the Monarch Mill Formation in the Middlegate basin, west-central Nevada, has yielded a middle Miocene (Barstovian Land Mammal Age) vertebrate assemblage, the Eastgate local fauna. Paleobotanical evidence from nearby, nearly contemporaneous fossil leaf assemblages indicates that the Middle Miocene vegetation in the area was mixed coniferous and hardwood forest and chaparral-sclerophyllous shrubland, and suggests that the area had been uplifted to 2700–2800 m paleoaltitude before dropping later to near its present elevation of 1600 m. Thus, the local fauna provides a rare glimpse at a medium- to high-altitude vertebrate community in the intermountain western interior of North America. The local fauna includes the remains of fish, amphibians, reptiles, birds, and 25 families of mammals. Carnivorans, the focus of this study, include six taxa (three of which are new) belonging to four families. Canidae are represented by the borophagine Tomarctus brevirostris and the canine Leptocyon sp. indet. The earliest record and second North American occurrence of the simocyonine ailurid Actiocyon is represented by A. parverratis sp. nov. Two new mustelids, Brevimalictis chikasha gen. et sp. nov. and Negodiaetictis rugatrulleum gen. et sp. nov., may represent Galictinae but are of uncertain subfamilial and tribal affinity. The fourth family is represented by the felid Pseudaelurus sp. indet. Tomarctus brevirostris is limited biochronologically to the Barstovian land mammal age and thus is consistent with the age indicated by other members of the Eastgate local fauna as well as by indirect tephrochronological dates previously associated with the Monarch Mill Formation. Actiocyon parverratis sp. nov. extends the temporal range of the genus Actiocyon from late Clarendonian back to the Barstovian. The Eastgate local fauna improves our understanding of mammalian successions and evolution, during and subsequent to the Mid-Miocene Climatic Optimum (~14–17 Ma).
Aura
|
2002
|
nr 11
23-25
The beautiful large eurasian bobcat was thought to have been extinct in Western and Central Europe as recently as 1900. The decimated populations have survived only in the Pyrenees, the Balkans, Carpathians and Scandinavia. For the last thirty years, there have been attempts at reintroducing the bobcat to Jura and the Alps, each with differing success. The author describes the geographical distribution and number of the bobcat populations, as well as the reasons for their decrease and the recreation programme in the Alps.
Gastrointestinal parasites were collected from 7 free-ranging Geoffroy's cats, Oncifelis geoffroyi from Lihué Calel National Park, Argentina. Also, fecal samples were analyzed from these animals and 3 other sympatric ones. The helminths were identified as Vigosospirura potekhina, Didelphonema longispiculata, Pterygodermatites cahirensis, Trichuris campanula, Ancylostoma tubaeforme, Toxocara cati, and Taenia sp. Fecal analysis revealed the presence of eggs of Capillaria sp. and an unidentified anoplocephalid tapeworm, and coccidian oocysts. The findings of V. potekhina, D. longispiculata, P. cahirensis, and T. campanula represent first records of these species in O. geoffroyi. Further, the former three had never been reported in South America.
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