Effect of immunization of ewes against prostaglandin F-2 alpha on the life-span of corpora lutea and oestrous behaviour during two breeding seasons.
Two adjuvants, Freund's complete adjuvant (FCA) and GNE (proprietary product; Intervet Ltd, The Netherlands), were used to immunize cyclic Finnish Landrace ewes (4-6/treatment) against a prostaglandin F-2 alpha-human serum albumin (PGF-HSA) conjugate. Ewes were randomized to the following treatments: (a) control-untreated, (b) control-5 mg HSA in FCA (control-HSA), (c) 5 mg PGF-HSA in FCA (FCA-5 mg), (d) 15 mg PGF-HSA in FCA (FCA-15 mg), (e) 5 mg PGF-HSA in GNE (GNE-5 mg) and (f) 15 mg PGF-HSA in GNE (GNE-15 mg). Ewes were monitored for oestrus (twice daily) and ovarian activity (progesterone concentrations in blood samples taken twice weekly) for 2 consecutive breeding seasons. In the first breeding season, the mean number of oestrous periods detected was 6.0, 5.7, 0.0, 0.2, 1.8 and 0.5 in control, control-HSA, FCA-5 mg, FCA-15 mg, GNE-5 mg and GNE-15 mg-assigned ewes, respectively [pooled standard error of difference (s.e.d.) = 1.2]. A persistent CL formed, on average, 10.0, 10.0, 29.8 and 32.5 days after primary immunization (pooled s.e.d. = 14.6) in 6/6 FCA-5 mg, 6/6 FCA-15 mg, 5/6 GNE-5 mg and 4/4 GNE-15 mg-assigned ewes, respectively; these CL were maintained for, on average, 138.7, 139.0, 127.8 and 129.0 days, respectively (pooled s.e.d. = 15.9).(ABSTRACT TRUNCATED AT 250 WORDS)
Ronayne
E
E
Department of Animal Nutrition and Physiology, Grange Research Centre, Dunsany, Co. Meath, Ireland.
Quirke
J F
JF
Enright
W J
WJ
Roche
J F
JF
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D000906:Antibodies / Q000032:analysis; D003338:Corpus Luteum / Q000502:physiology*; D003340:Corpus Luteum Maintenance / Q000187:drug effects*; D015237:Dinoprost / Q000276:immunology*; D004971:Estrus / Q000502:physiology*; D005260:Female; D005620:Freund's Adjuvant / Q000494:pharmacology; D007114:Immunization; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D011897:Random Allocation; D012621:Seasons; D012756:Sheep / Q000097:blood / Q000502:physiology*
D000276:Adjuvants, Immunologic; D000906:Antibodies; D011374:Progesterone; D005620:Freund's Adjuvant; D015237:Dinoprost