The production of anti-H-Y monoclonal antibodies: their potential use in a sex test for bovine embryos.

In an attempt to improve the accuracy of sexing bovine embryos, new anti-H-Y monoclonal antibodies were produced and selected, using an extended screening procedure. In addition to the commonly used screening of soluble H-Y antigen sources, such as testis supernatant and Daudi supernatant, the binding specificity to cell surface H-Y antigen was tested also. A radioimmunoassay (RIA) employing male and, as a control, female bovine lymphocytes, and enzyme-linked immunosorbent assays (ELISAs) on solubilized membrane fractions resulted in the selection of a number of clones producing monoclonal antibody (mAb) with male-enhanced binding.

Daudi supernatant, unlike other H-Y antigen sources, exerts a sex-reversing effect on embryonic chick gonad differentiation.

In vitro cultures of intact chick gonads (organ cultures) and reaggregation cultures of dispersed gonad cells (roller cultures) were made. Gonads or gonad cells from 7-day-old chick embryos, at the stage when sex-specific differentiation begins, were cultured in the presence of presumed H-Y antigen-containing supernatants, or co-cultured in the presence of H-Y antigen-producing cell lines. The H-Y antigen-producing cells tested were of human, mouse, bovine and chicken origin.

Post-weaning anoestrus in primiparous sows: LH patterns and effects of gonadotropin injection and boar exposure.

Post-weaning anoestrus was studied in eighteen primiparous sows, selected from a breed showing a high proportion of anoestrous sows. The sows were studied from late lactation, through weaning at day 29 post-partum (p.p.

A comparative study on the use of bovine and murine monoclonal antibodies for passive immunization in cattle.

In the present experiments the efficacy of murine and bovine monoclonal antibodies for passive immunization in cattle was compared. The in vivo immunoneutralization of pregnant mare serum gonadotrophin (PMSG) by murine and bovine antibodies after repeated administration was chosen as a model for this study. Results indicate that repeated injections of murine monoclonal antibodies against PMSG (mMCA) alone did not, or only to a small extent, elicit an anti-mouse immune response.

Construction of a bovine-murine heteromyeloma cell line; production of bovine monoclonal antibodies against rotavirus and pregnant mare serum gonadotrophin.

Bovine-murine heteromyeloma cell lines were prepared by fusing lymphoid cells from a bovine leukemia virus (BLV)-infected cow with mouse myeloma cells. Selection of hybrid cell colonies was based on the ratio of bovine and murine chromosomes, the presence of cell-surface immunoglobulins and growth characteristics. First-generation fusion partners were compared for fusion efficiency and the number of antigen-specific antibody-producing clones generated.