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.

Immunohistochemical study of the local immune response to Fasciola hepatica in primarily and secondarily infected goats.

The distribution of CD2, CD4, CD8, gamma/delta T-lymphocytes, B-cells and IgG lambda-light chain (lambda-IgG) containing cells were analysed in the inflammatory infiltrate associated to hepatic lesions and gallbladder (HL), and in hepatic lymph nodes (HLN) of goats primarily and secondarily infected with Fasciola hepatica. In the HL, CD2 and CD8 T-cells were more numerous (p=0.01) in secondarily rather than in primarily infected goats, whereas CD4 T-lymphocytes were less numerous than CD8 and showed no significant change in both groups. The ratio CD4/CD8 was 0.66 and 0.39 for primarily and secondarily infected goats, respectively. In contrast, in the HLN, CD4 were more numerous than CD8 T-cells, the ratio CD4/CD8 was 2.0 in control, 1.5 and 1.3 in primary and secondary infections, respectively. Gamma/delta T-lymphocytes were scarce in the HL and moderate in the HLN of both primarily and secondarily infected animals. B-cells (IgM+, lambda-IgG+ or CD79+) varied from scarce or moderate in the HL to abundant in the HLN, where CD79+-cells were mainly located in lymphoid follicles and IgM and IgG in plasma-cells of the medullary cords, suggesting an intense local humoral immune response. However, this response did not prevent the hepatic damage in secondarily infected goats, in which hepatic lesions were more severe than in primarily infected ones.

Elaeophora elaphi n. sp. (Filarioidea: Onchocercidae) parasite of the red deer (Cervus elaphus). With a key of species of the genus Elaeophora.

We described a new species of nematode filarioid (Onchocercidae) parasiting the hepatic vessels of the red deer Cervus elaphus. This new species is characterized by the number and disposition of the papillae on the genital area of the male, and the presence and characteristics of an "area rugosa" situated just in front of the ventral impair precloacal papilla. We discussed this new species, giving a key to the identification of all the known species of the genus Elaeophora.