Effects of immunization against alpha-inhibin using two adjuvants on daily sperm production and hormone concentrations in ram lambs.
Twenty-five ram lambs were immunized against alpha-inhibin peptide emulsified in Freund's adjuvant (FRA), Emulsigen (EML) containing an oligodeoxynucleotide as an immunostimulant, or adjuvant without alpha-inhibin antigen (control). Four immunizations were administered during an 85-d period, after which testes were obtained for determination of daily sperm production (DSP) and histological evaluation. alpha-Inhibin antibody (Ab) titers were 70-fold greater in lambs treated with FRA than in EML-treated ram lambs. alpha-Inhibin immunization had no effect on testes weight or on plasma concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. Mean DSP/g tended (P=0.1) to be greater in alpha-inhibin-immunized (EML=17.6x10(6); FRA=15.8x10(6)) ram lambs than in control animals (14.4x10(6)). One of the 8 control ram lambs had an elevated DSP/g, which was a statistical outlier. Without data from this lamb, DSP/g was increased (P<0.01) in alpha-inhibin-immunized ram lambs by 28% over controls. No association was found between the titer of alpha-inhibin Ab developed and DSP/g. Histologically, the percentage of testicular area occupied by seminiferous tubules differed (P=0.01) by treatment and was greatest (82%) in EML-treated ram alpha-inhibin-immunized lambs and lowest (74%) in control animals. Percentage tubular area and DSP/g were correlated (r=0.57, P=0.003). Findings show that (1) the extent of the increase in DSP/g is not dependent on the titer of alpha-inhibin Ab; (2) the increase in DSP/g is achieved through an increase in the mass of seminiferous tubules; and (3) FRA elicits a greater alpha-inhibin Ab titer than EML containing an oligodeoxynucleotide.
Voge
J L
JL
Department of Animal Science, University of Minnesota, St. Paul, MN 55108, USA.
Parker
J B
JB
Wheaton
J E
JE
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D057134:Antibodies, Neutralizing / Q000502:physiology; D005640:Follicle Stimulating Hormone / Q000097:blood; D005620:Freund's Adjuvant / Q000494:pharmacology; D007114:Immunization / Q000662:veterinary; D007265:Inhibins / Q000276:immunology*; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009929:Organ Size; D012671:Seminiferous Tubules / Q000033:anatomy & histology / Q000187:drug effects / Q000276:immunology; D012756:Sheep; D013076:Sperm Count / Q000662:veterinary*; D013091:Spermatogenesis / Q000187:drug effects* / Q000276:immunology; D013737:Testis / Q000033:anatomy & histology / Q000187:drug effects* / Q000276:immunology; D013739:Testosterone / Q000097:blood
D000276:Adjuvants, Immunologic; D057134:Antibodies, Neutralizing; C094377:inhibin-alpha subunit; D013739:Testosterone; D007265:Inhibins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D005620:Freund's Adjuvant