Restriction fragment length polymorphism of DQB and DRB class II genes of the ovine major histocompatibility complex.

The ovine major histocompatibility complex (MhcOvar) class II region was investigated by Southern blot hybridizations using ovine probes specific for the second exons of Ovar-DRB and Ovar-DQB genes. Multiple bands were revealed when genomic DNA was digested with each of five restriction enzymes (BamHI, EcoRI, HindIII, PvuII and TaqI), and successively hybridized with the two radiolabelled ovine probes. Restriction fragment length polymorphisms (RFLPs) were analysed in 89 sheep originating from six inbred families and the inheritance of the fragment patterns was determined.

[Induction of interferon activity in nasal mucus by association of levamisole by systemic route -- inactivated virus by local route (author's transl)].

Calf respiratory disease could have a non-specific origin. The respiratory tract bacterial flora is pathogen only if the animal faces stress which decreases the defense capacities of the respiratory mucosa. The simultaneous administration of UV irradiated IBR virus by nasal route and of levamisole by systemic route induces a protection which is accompanied by interferon synthesis in the nasal mucus.

Transfer of antibodies against the CPD virus through colostrum and milk.

Newborn lamb immunoglobulins are of maternal origin and the transfer is done exclusively by colostrum and milk (syndesmochorial placentation). Antibody levels in colostrum and in maternal serum are the same at the moment of lambing. Milk antibodies are synthesized by cells which invade the udder at the end of the milking period.