Plains viscacha were established in the laboratory to Spanish by Llanos & Crespo (), and some details of reproduction were given. Llanos, A. and J. Crespo. Ecología de la vizcacha (Lagostomus maximus maximus Blainv.) en el nordeste de la provincia de Entre Ríos. Rev. Llanos, A. C. and J. A. Crespo. Ecología de la vizcacha (Lagostomus maximus maximus Blainv.) en el nordeste de la Provincia de Entre Ríos. Revista de.

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The diversities of plant species in the environment, as well as in the diet, were estimated using the standardized Shannon-Wiener function H’, Col- well and Futuymaand compared with the test of Hutcheson Vida Sil- vestre Neotropical, 3: Once the specificity of PRL-customized primers was established see Material and Methodswe evaluated the variations of PRL gene rcespo in the pituitary gland of L.

During lactation, pituitary PRL immunoexpression decreased to values similar to the basal production measured in non-ovulating non-pregnant animals Figure 6.

Comparing food frespo space use between these two closely related species may elucidate whether their spatial segregation contributes to reduce competition. The objectives of this paper are to analyze the diet composition and habitat prefe- rences of vizcacha, and their changes in relation to food availability in a Northern Pata- gonia environment.

Spectrochimica Acta Part A: After bleeding, animals were sacrificed by an intracardiac injection of Euthanyle 0.

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Previous studies have indicated that the adult male viscacha is a photoperiod-dependent seasonal breeder [ 2945 — 48 ]. Plant spe- cies were grouped in four categories according to vizcaacha life form: Regrettably, neither of these techniques proved to be successful for PRL serum determination in vizcachas. To receive news and publication updates for International Journal of Endocrinology, enter your email address in the box below.


Vizcacha’s diet in La Payunia, within the most arid and elevated region of its distribution, showed a similar variety since half of the plant species present in the field were included. The pineal gland of female viscacha presented an oval-like morphology, elongated, with a stalk connected to the brain.

Gonzalez del Solar for his editorial suggestions. More studies about herbi- vores dietary overlap, and their capability of habitat modification are needed in Nor- thern Patagonia.

Click here to sign up. Materials and Methods 2. Consumption of chamae- phytes was higher in Escoriales, whose plains differed from the others due to the high chamaephytes availability. Melanin pigmentation in bovine pineal gland and its possible correlation with gonadal function.

Neuromelanin in human dopamine neurons: The morphology, histochemical properties, and ultrastructure of the pigmented cells may indicate that the melanogenesis takes place in these cells, and then, the melanin is transferred to pinealocytes and interstitial cells.

Forbs availability, strongly related to dietary quality Branch et ai. Selectivity of plant categories by the vizcacha Grasses 0. Pituitary expression of PRL increased during pregnancy. The photomicrograph shows a semithin section with numerous pigmented cells arrowheads in close relation to blood vessels v.

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This hypothesis states that feeding selectivity increases in cir- cumstances of low diversity and abundance of food, forced by its low quality. Ultrathin sections were stained with uranyl acetate and lead citrate [ 36 ] and were observed under a Siemens Elmiskop I electron microscope.

Cell types in the pineal gland of vizcaacha horse: Field and laboratory design Duringfive samplings were carried out in crspo 1O-km2 areas, represen- tative of cres;o four above defined habitats. Daily morphological variations in the viscacha Lagostomus maximus maximus retina. Slides of this material were analyzed by the microhistological method of Baumgartner and Martin ; 50 fields per sample unit at X microscope magnification were examined, using plant reference material from La Payunia stored in the Ruiz Leal Herbarium IADIZA, Argentinaand described by Puig et al.


Chile, Argentina, Uruguay, Paraguay: Intra- and interassay coefficients of variation were 7.

The following techniques were applied: During gestation, particularly from midpregnancy, we detected a significant accumulation of pituitary PRL that reached its maximum at term pregnancy. The immunoexpression of PRL increased in mid- and term pregnant groups, exhibiting in the latter the highest reactivity, especially in those lactotropic cells closest to the capillaries.

Lux-Lantos2,3 A. E; Esco- fizcachaand food availability per microhabitat pI: Genus level, and species level when possible, were reached during plant cuticle identification. Variations in the number of pigmented vzcacha and serum hormone levels between nonpregnant and pregnant viscachas. All females captured from early autumn to spring April—September were pregnant.

Poa, a good forage even during the dormancy period, was selecti- vely searched for in winter beyond the surrounding denuded area of vizcacheras also in a semiarid grassland Giulietti and Jackson A high selectivity ocurred in habitats and sea- sons with low plant diversity. Puma Puma concolor and wild cats Oncifelis geoffrovi and O.

Both coarse grasses tended to be avoided, and the relevance of Stipa as the main complementary element in vizcacha’s diet should be attributed to its high availability rather than to its quality. The viscachas were quickly sacrificed by intracardiac injection of Euthanyle 0.

Molecular and Biomolecular Spectroscopy. Large size 5 kg of mean body weightnocturnal activity creapo distribution centered in alluvial plains Weir make the vizcacha Lagostomus rnaximus to stand out from the family Chinchillidae Order Rodentia.

This area is located within the northernmost unit of the Patagonian Biogeographical Province Cabrera and Willink