Immunization of heifers against gonadotropin-releasing hormone: antibody titers, ovarian function, body growth, and carcass characteristics1
Autor: | Daniel J. Prendiville, Mark A. Crowe, M. Finnerty, W. J. Enright, James F. Roche, N. Hynes |
---|---|
Rok vydání: | 1995 |
Předmět: |
Estrous cycle
endocrine system medicine.medical_specialty animal structures animal diseases medicine.medical_treatment Antibody titer Ovary General Medicine Gonadotropin-releasing hormone Biology Active immunization Animal science Endocrinology medicine.anatomical_structure Immunization Internal medicine Genetics medicine Animal Science and Zoology Adjuvant hormones hormone substitutes and hormone antagonists Food Science Conjugate |
Zdroj: | Journal of Animal Science. 73:2382-2389 |
ISSN: | 1525-3163 0021-8812 |
Popis: | To investigate the effects of active immunization of cyclic beef heifers with different doses of a human serum albumin-Cys-Gly-GnRH (HSA-GnRH) conjugate on antibody titers, ovarian function, body growth, and carcass characteristics, 32 heifers (BW = 477 ± 7.1 kg ; mean ± SE) were assigned to one of four immunization treatments :.1 mg of HSA or.01,.1, or 1.0 mg of HSA-GnRH, respectively. All heifers received a primary (d 0) and booster (d 28) immunization using DEAE-dextran as adjuvant. The duration of the experiment was 158 d. Overall antibody titers against GnRH were greater (P 21 d) were 1/8, 8/8, 7/8, and 8/8, respectively. The interval from primary immunization to anestrus (40.7 ± 6 d) and the duration of anestrus (78 ± 7 d) were not affected by dose of HSA-GnRH conjugate. The number of ovulations detected was reduced (P .10) of treatment on overall growth rate (ADG.54 ±.041 and.51 ±.054 kg for control and GnRH-immunized heifers, respectively) or carcass measurements. However, ADG was reduced for GnRH-immunized heifers between d 56 and 84. In , immunization of heifers with a HSA-GnRH conjugate invoked an immune response in all heifers and induced anestrus in 23/24 heifers for 82.8 ± 6.9 d ; dose of HSA-GnRH conjugate did not affect the incidence or duration of anestrus. |
Databáze: | OpenAIRE |
Externí odkaz: |