Biomedical subjects

S Hernández-Rodríguez

Publications and source records attributed to S Hernández-Rodríguez.

7 recordsLinked to original sources

PubMed2000

Experimental bovine hypodermosis in Spain.

An experimental survey was carried out in western Spain to investigate both the chronobiology of Hypoderma spp. and the immunoresponse of their bovine hosts. This study was initiated with a new system of obtaining Hypoderma spp. larvae directly from their host, including the eclosion of adults from their pupae, infestation under natural but controlled conditions, and confirmation of the resulting infection. This survey was carried out over 2 cattle grub seasons; it was possible to infest and reinfest the experimental animals and to monitor them by both parasitological methods and by an enzyme-linked immunosorbent assay. This method permitted the evaluation of the development of anti-Hypoderma antibodies during the experiment. The experimental design also enabled us to establish the period of detectable H. lineatum infection to be from December until the end of April with the largest number of warbles observed during March and April. After a pupal period of < 30 d, adults were seen in April and May. Hypoderma bovis (de Geer) showed a delay of 2 m.o. relative to H. lineatum (de Villiers). This study reports a completed biological life cycle of Hypoderma spp. under controlled conditions in both natural and experimental environments.

Animals↗

PubMed1998

Comparative scanning electron microscopy of third-instar Hypoderma spp. (Diptera: Oestridae).

Scanning electron microscope study of third-instar larvae of four species of Hypoderma revealed differences among species in the pattern of spination, spine morphology and morphology of the spiracular plates. These observations identify characters that enable the differentiation of Hypoderma actaeon and H. diana, parasitizing red deer (Cervus elaphus) in Europe, and provide additional characters for differentiating H. bovis and H. lineatum parasitizing cattle.

Animals↗

PubMed1998

Method for collecting Hypoderma spp. (Diptera: Oestridae) larvae from cattle.

A new method for collecting 3rd-instar Hypoderma lineatum (Villers) and Hypoderma bovis (L.) is described. A procedure for carrying out chronobiological and other studies involving the life cycle of these flies is included. The larvae are collected from cattle using a dressing made of a circle of cardboard attached to a piece of tulle similar in color to the coat of the animal. These small cloth cages were attached to the animal skin with fast-drying contact glue wherever the swellings produced by 2nd- or 3rd-instar Hypoderma spp. had been previously detected. Each animal was inspected daily to detect the appearance of new larvae. This procedure allows the collection of each emerged larva without contact with other larvae and avoids friction of the cloth cages or dressing with the larvae, thus reducing larval death and increasing viability of the parasite.

Animals↗

PubMed1997

Deer hypodermosis.

Hypodermyiasis is a common myiasis which affects a wide variety of deer species in many parts of the world. In this article a great review of the disease is made, treating the different species of flies that cause the myiasis in the different species of hosts. Biologies of deer and flies are also studied, with special dedication to the chronobiology of the life cycle of the parasite. Prevalence and intensity of parasitization in many parts of Europe are recorded like expression of the importance of hypodermyiasis in deer. Finally, some remarks about treatment and control are included.

Animal Husbandry↗

PubMed1994

Comparison of the use of secretory and somatic antigens in an ELISA for the serodiagnosis of hypodermosis.

An antigen was prepared from metabolic products which were produced by maintaining first instar larvae of Hypoderma lineatum in RPMI tissue culture medium for 48 h. Three major proteins were identified in the secretory products and were characterised in terms of their molecular weights and iso-electric points. The antigen compared favourably with a soluble extract of larvae when used in an enzyme-linked immunosorbent assay (ELISA) against a panel of control sera and 2000 bovine sera collected from farms in Andalucia, Spain.

Animals↗

PubMed1993

Immunological and histological study of T- and B-lymphocyte activity in canine visceral leishmaniosis.

Lymphocyte activity during canine leishmaniosis was studied by histological and immunological methods in experimental and natural infections. Eight dogs were inoculated with 5 x 10(7) promastigotes of Leishmania infantum, LEM 75, zimodeme MON-1, and maintained for 110 days post-infection. Another eight dogs with advanced natural infection were identified by parasitological and serological methods. Three techniques were used: the lymphocyte transformation test (LTT) to study T-cell activity, immunofluorescence assay and enzyme-linked immunosorbent assay to measure antibody production (B-cell activity), and methyl green-pyronin staining to assess tissue responses of lymphocytes. There was a noticeable B-cell response, reflected both histologically and immunologically. High percentages of activated lymphocytes and plasma cells were evident in lymphoid organs and production of specific antibodies was seen throughout the infection. LTT results showed a T-cell unresponsiveness during canine leishmaniosis. These same immunohistological features were observed, although to different degrees, in both experimental and natural infections.

Animals↗

PubMed1992

Sarcocystis jorrini sp. nov. from the fallow deer Cervus dama.

Sarcocystis jorrini sp. nov. isolated from the muscle of naturally infected fallow deer (Cervus dama) from the Doñana National Park (Spain) is described by light and electron microscopy. Sarcocysts were macroscopic (2.7 x 1.4 mm) and were found in all striated muscle, including that of the esophagus and the heart. As visualized by light microscopy, the cyst walls were formed by mammilated protrusions surrounded by a coating of connective tissue measuring 10-35 mm in thickness. Electron microscopy revealed that the parasitophorous vacuole was serrated in appearance, with numerous pinocytic vesicles running along its whole length. Villar protrusions were of varying shape and were square, rectangular, or linguiform in cross section. The core of the villi contained small dense granules and microfilaments, which were more abundant in peripheral areas. Ground substance contained larger dense granules clustered around the base of villi. The sarcocyst was surrounded by a secondary cyst wall composed of collagen fibrils and fibrocytes. S. jorrini is the first macroscopically visible sarcocyst of the genus Cervus reported to have a secondary cyst wall.

Animals↗