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Da Silva-Álvarez E, Ortiz-Rodríguez J, Gaitskell-Phillips G, Serres C, García-Rodríguez B, Gutiérrez-Cepeda L, Martín- Cano F, Echegaray A, Escartin-Casas N, Requena F, Gil M, Peña F, Ortega-Ferrusola C. Evaluation of testicular echotexture with Ecotext as a diagnostic method of testicular dysfunction in stallions. Theriogenology 2022; 185:50-60. [DOI: 10.1016/j.theriogenology.2022.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 12/16/2021] [Accepted: 03/07/2022] [Indexed: 11/28/2022]
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Junco JA, Fuentes F, Millar RP. A dual kisspeptin-GnRH immunogen for reproductive immunosterilization. Vaccine 2021; 39:6437-6448. [PMID: 34489132 DOI: 10.1016/j.vaccine.2021.07.080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 07/07/2021] [Accepted: 07/28/2021] [Indexed: 02/03/2023]
Abstract
GnRH immunogens have been extensively employed in immunocontraception of animals. While they are effective, they are not 100% efficacious and of limited duration. GnRH secretion is dependent on upstream stimulation by kisspeptin. We therefore hypothesised that a dual immunogen combining GnRH and kisspeptin may be more efficacious through targeting two levels of the axis. We have previously shown GnRH immunogen elicits permanent sterilisation when sheep are vaccinated neonatally suggesting that the efficacy of GnRH immunisation may be dependent on the stage of reproductive development. We have now studied over 300 days the efficacy of immunisation with a dual immunogen comprising GnRH linked to kisspeptin via a hepatitis B T helper peptide sequence (GKT) administered to male and female rats prepubertally, pubertally and as adults. At all stages of development all immunised animals produced antibodies to GnRH, kisspeptin and GKT but differentially in titre with respect to sex and stage of development. In immunised adult, prepubertal and pubertal males testosterone and testes length was markedly reduced by 60 days and remained at low levels until day 150. Thereafter, testosterone recovered to pre immunisation levels and testes length increased to a maximum of about 40% of controls. 80% of males were infertile in three matings over 250 days. In prepubertal and pubertal female rats a single immunisation at day 0 reduced estradiol to low levels by day 60 which remained low until termination of the experiment on day 300. In matings of these females with fertile males on days 90, 120 and 250, 74% of prepubertal females were infertile and impressively, 100% (10/10) of pubertal females were infertile after a single immunisation on day 0. These findings set the scene for exploration of immunosterilisation of wild and domestic animals after a single immunisation.
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Affiliation(s)
- Jesus A Junco
- Prostate Cancer Department, Centre for Genetic Engineering and Biotechnology of Camaguey. Ave Finlay y Circunvalación Norte, CP 70100 Camaguey, Cuba
| | - Franklin Fuentes
- Prostate Cancer Department, Centre for Genetic Engineering and Biotechnology of Camaguey. Ave Finlay y Circunvalación Norte, CP 70100 Camaguey, Cuba
| | - Robert P Millar
- Centre for Neuroendocrinology, Department of Immunology, Faculty of Health Sciences, University of Pretoria, Gezina 0084, Pretoria, South Africa; Institute of Infectious Disease and Molecular Medicine, Department of Integrative Biomedical Sciences, Faculty of Health Sciences, University of Cape Town, Observatory 7925, Cape Town, South Africa.
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Schütz J, Rudolph J, Steiner A, Rothenanger E, Hüsler J, Hirsbrunner G. Immunization against Gonadotropin-Releasing Hormone in Female Beef Calves to Avoid Pregnancy at Time of Slaughter. Animals (Basel) 2021; 11:ani11072071. [PMID: 34359199 PMCID: PMC8300343 DOI: 10.3390/ani11072071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/08/2021] [Accepted: 07/09/2021] [Indexed: 11/16/2022] Open
Abstract
Precocious puberty in beef heifers can result in unwanted pregnancies due to accidental breeding by farm bulls. Inbreeding, premature calving followed by dystocia and a high stillbirth rate or slaughtering of pregnant heifers are the consequences of this behaviour. The aim of the study was to postpone puberty by using Improvac®, an anti-GnRH vaccine. Therefore, n = 25 calves were twice vaccinated, once at the age of 5 and then at 6.5 months. n = 24 calves served as unvaccinated case controls. The onset of puberty was assigned if progesterone analysis in the blood exceeded 1 ng/mL. Progesterone values were excluded if the corresponding serum cortisol levels were ≥60 nmol/L. Our target was met, as in the vaccinated group none of the calves exceeded a progesterone value >1 ng/mL until the scheduled age of slaughter at 11 months and only 12.5% of the animals exceeded a progesterone value of 1 ng/mL over the whole measuring period (>400 days) compared with 56.5% of the calves in the control group. In conclusion, the favourable results from our study using the vaccine Improvac® represent an animal-friendly, non-invasive and reliable way to avoid early pregnancy in heifers as well as the slaughter of pregnant cattle.
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Affiliation(s)
- Julia Schütz
- Nutztierpraxis Rudolph AG, CH-6280 Hochdorf, Switzerland; (J.S.); (J.R.)
| | - Jürn Rudolph
- Nutztierpraxis Rudolph AG, CH-6280 Hochdorf, Switzerland; (J.S.); (J.R.)
| | - Adrian Steiner
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109 a, CH-3012 Bern, Switzerland;
| | | | - Jürg Hüsler
- Institute of Mathematical Statistics and Actuarial Science, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland;
| | - Gaby Hirsbrunner
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109 a, CH-3012 Bern, Switzerland;
- Correspondence: ; Tel.: +41-31684-2344
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Viana JHM, Pereira NES, Faria OAC, Dias LRO, Oliveira ER, Fernandes CAC, Siqueira LGB. Active immunization against GnRH as an alternative therapeutic approach for the management of Bos indicus oocyte donors diagnosed with chronic cystic ovarian disease. Theriogenology 2021; 172:133-141. [PMID: 34166988 DOI: 10.1016/j.theriogenology.2021.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 06/14/2021] [Accepted: 06/16/2021] [Indexed: 10/21/2022]
Abstract
The aim of this study was to evaluate the effect of active immunization against GnRH in Nelore (Bos indicus) cows repeatedly used as oocyte donors that developed chronic cystic ovarian disease (COD). In the first experiment, ovarian and uterine features were first compared between COD cows (n = 15) and healthy cows (n = 22, cycling control group) from the same breed and herd. Cows with COD had a greater number of large (P < 0.0001) and medium follicles (P < 0.01) but lesser small follicles (P < 0.05) than cycling controls. Mucometra was diagnosed in 73.3% of COD cows, but in none of the controls. No difference in average thickness of the endometrium was detected between groups; however, endometrial thickness and mucometra score were negatively correlated (R = -0.73, P = 0.0029) in COD cows. In the second experiment, COD cows were randomly allocated into two experimental groups, which received two 1.0 mL SC injections of either an anti-GnRH vaccine (COD immunized group, n = 8) or saline (COD control group, n = 7), given 28 days apart. Cows were examined weekly by transrectal ultrasonography during nine consecutive weeks after the first injection to evaluate the number and distribution of follicles among size classes, endometrial thickness, and presence of clinical mucometra. Vaccination against GnRH resulted in a progressive suppression of follicle growth and a reduction in the average size of the largest follicle, as well as in the number of large follicles (P < 0.01) in COD immunized cows compared with COD controls from week 7 onwards. Conversely, the number of small follicles in the COD immunized group increased after week 5 and was greater (P = 0.0023) than controls on week 9. Endometrial thickness and mucometra score were not affected (P > 0.05) by immunization against GnRH. In the third experiment, the COD immunized cows with effective suppression of follicle growth four weeks after the 2nd injection (n = 6) were submitted to three consecutive ovum pick-up (OPU) sessions (weeks 10, 11, and 12) for in vitro embryo production (IVEP). Cumulus-oocyte complexes (COC) collected from slaughterhouse ovaries were used as controls for IVEP. COD cows with produced 25.0 ± 3.8 COC per OPU session with no apparent detrimental effect of anti-GnRH vaccine on oocyte developmental potential in vitro, i.e., we observed similar cleavage rate (P = 0.5914) and greater blastocyst rate (P = 0.0177) in immunized cows compared with COC from slaughterhouse controls. Finally, in the fourth experiment wave emergence and follicular dynamics after follicle ablation were compared between COD immunized cows with effective suppression of follicle growth and a subset (n = 6) of the cycling, control group. No follicles grew beyond 4 mm diameter after follicle ablation in the COD immunized group, whereas a normal follicular wave emergence occurred in cycling controls. Antral follicle count was similar between cycling controls and COD immunized groups at 24 h and 96 h post-follicle ablation (P > 0.05), but greater in cycling controls at 48 h and 72 h post-follicle ablation (P < 0.05). In summary, our results suggest that active immunization against GnRH is effective to induce the regression of follicular cysts as well as increase the number of small follicles growing on the ovaries, in oocyte donors diagnosed with chronic COD, with no apparent negative effect on oocyte developmental potential in vitro.
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Affiliation(s)
- Joao Henrique Moreira Viana
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-901, Brazil; Universidade José do Rosário Vellano, Alfenas, MG, 37130-000, Brazil; Universidade de Brasília, Brasília, DF, 70910-900, Brazil.
| | | | | | | | | | | | - Luiz Gustavo Bruno Siqueira
- Universidade José do Rosário Vellano, Alfenas, MG, 37130-000, Brazil; Embrapa Gado de Leite, Juiz de Fora, MG, 36038-330, Brazil
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R. Huenchullan P, Vidal S, Larraín R, Saénz L. Effectiveness of a New Recombinant antiGnRH Vaccine for Immunocastration in Bulls. Animals (Basel) 2021; 11:ani11051359. [PMID: 34064713 PMCID: PMC8151010 DOI: 10.3390/ani11051359] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/05/2021] [Accepted: 05/07/2021] [Indexed: 12/03/2022] Open
Abstract
Simple Summary Castration of males is a common procedure in cattle production. Surgical procedures are most commonly used, but there is an increasing interest in non-invasive alternatives to avoid risk of infection, bleeding, pain, stress and to improve animal welfare. Immunization against gonadotropin-releasing hormone is currently being used in livestock, but there is only one commercially available vaccine for cattle and results regarding the number of doses needed to maintain castration are variable. The efficacy, safety, and production parameters of a new antigen for immunocastration in bulls was assessed. Results showed that two doses of the vaccine to 40 10-month-old bulls achieved testosterone suppression below productive performance. Live weight at slaughter and carcass yield was greater in immunized animals than in surgically castrated cattle. Castration effects of the vaccine were maintained until the end of the trial at 24 weeks. Abstract Castration by surgical techniques is common in livestock; however, post-surgery complications and concerns for animal wellbeing have created a need for new non-invasive alternatives. The objective of this study was to evaluate immunocastration in bulls using antigen GnRX G/Q; a recombinant peptide proved to be effective in laboratory and companion animals. A nine-month trial with 80 9-month-old Normand x Hereford bulls, kept in a pastured system, was conducted. The herd was divided in half with 40 bulls surgically castrated (SC) and 40 castrated by immunization against GnRH (IC). The antigen was injected on days 0 and 40 of the experiment. After the second dose, the IC group had elevated GnRH antibodies and decreased testosterone levels (below 5 ng/mL) that were maintained for 23 weeks. At slaughter on day 190, the immunocastrated group obtained a higher weight, hot carcass, and dressing percentage than the SC group. There was no difference in pH, color of meat, fat coverage, cooking loss, or tenderness between groups. The bulls showed no inflammatory reaction at the injection site or adverse side effects from the vaccine. Our results demonstrate that immunocastration with GnRX G/Q is an efficient and safe alternative to surgical castration in livestock. Additional work evaluating antigen effects over a longer period is needed to validate commercial viability.
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Affiliation(s)
- Paula R. Huenchullan
- Programa de Doctorado en Ciencias Silvoagropecuarias y Veterinarias, Universidad de Chile, Santiago 8820808, Chile;
| | - Sonia Vidal
- Laboratory of Veterinary Vaccines, Department of Animal Biology, Faculty of Veterinary and Animal Science, Universidad de Chile, Santiago 8820808, Chile;
| | - Rafael Larraín
- Departamento de Ciencias Animales, Facultad de Agronomía e Ingeniería Forestal de la Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago 7820436, Chile;
| | - Leonardo Saénz
- Laboratory of Veterinary Vaccines, Department of Animal Biology, Faculty of Veterinary and Animal Science, Universidad de Chile, Santiago 8820808, Chile;
- Correspondence:
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Doroteu EM, Viana JHM, Ferreira Junior JA, Macedo JTA, Oliveira RA, Pedroso PMO. Effect of a single or two doses of an anti-GnRH vaccine on testicle morpho-functional characteristics in Nelore bulls. Trop Anim Health Prod 2021; 53:153. [PMID: 33547980 PMCID: PMC7867542 DOI: 10.1007/s11250-021-02600-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 01/27/2021] [Indexed: 11/26/2022]
Abstract
The aim of this study was to compare testicle morpho-functional characteristics in bulls undergoing a single or two immunizations against GnRH. Nelore (Bos taurus indicus) bulls were randomly allocated into three experimental groups: G1 (n=12), a single 400 μg dose of anti-GnRH vaccine on day 0; G2 (n=11), a first 400 μg dose of anti-GnRH vaccine on day 0 followed by a second (boost) dose 30 days later; and control group (CG, n=12), 1 mL saline 0.9% at day 0. Every 30 days, from day 0 until slaughter at day 90, the bulls were weighed and underwent testicular biometry, semen collection and analysis, and blood sample collection for testosterone measurement. Immediately after slaughter, the testicles were removed and transport at 15°C to the laboratory for histopathological analysis. There was a decrease in testicular height (P=0.0476), width (P=0.0021), and in scrotal circumference (P=0.0001), after either a single (G1) or two (G2) immunizations against GnRH. Both G1 and G2 had lower testosterone concentrations than CG from day 60 on (P<0.01), but in G2, it was also lower than in G1 at day 90 (P=0.0006). All sperm parameters were affected by active immunization against GnRH (P<0.05), and in G2, averages were lesser (P<0.05) than in G1 from day 60 on. No signs of seminiferous tubule degeneration were found in any sample from the CG, contrasting with 75.0% and 100.0% of the samples from G1 and G2, respectively. In summary, immunocastration affected testicle morpho-functional characteristics in bulls in a time- and dose-dependent way.
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Affiliation(s)
- Emanuel M Doroteu
- Universidade de Brasília, Brasília, DF, 70636-200, Brazil.
- Universidade de Brasília, Campus Universitário Darci Ribeiro, ICC, Ala Sul, Asa Norte, Brasília, DF, 70297-400, Brazil.
| | - Joao H M Viana
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-190, Brazil
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Yao Z, Si W, Tian W, Ye J, Zhu R, Li X, Ji S, Zheng Q, Liu Y, Fang F. Effect of active immunization using a novel GnRH vaccine on reproductive function in rats. Theriogenology 2018; 111:1-8. [PMID: 29407422 DOI: 10.1016/j.theriogenology.2018.01.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 01/13/2018] [Accepted: 01/18/2018] [Indexed: 11/29/2022]
Abstract
To investigate the effect of gonadotropin-releasing hormone 2-multiple antigen peptide (GnRH2-MAP) on reproductive function. In our study, 20-day-old male rats (n = 90) were randomly allocated to one of three treatment groups: GnRH2-MAP immunization, GnRH2 immunization, and non-immunized control groups. The immunized animals were administered three doses of GnRH2-MAP or GnRH2 vaccines from 0 to 6 weeks at 2-week intervals. The control group only received oil adjuvant. Blood and right testis samples were collected, and the left testis was weighed and its volume was measured at 0, 2, 4, 6, 8, 10 and 12 weeks after the first immunization. The serum antibody titer and testosterone concentration were determined by ELISA, and the right testis samples were collected for histological analysis. The results revealed that the serum of vaccinated rats elicited a significantly higher antibody titer and a lower T concentration compared with the control group two weeks after the first immunization (P < 0.05), but the highest antibody titer and lowest T concentration were found in animals treated with GnRH2-MAP (P < 0.05). The second immunization resulted in a significant decrease in testicular weight and volume (P < 0.05) in both immunized groups compared to the control, but these values were significantly lower in the GnRH2-MAP group than in the GnRH2 group. Furthermore, seminiferous tubules revealed more significant atrophy in the GnRH2-MAP group than in the GnRH2 group, and no sperm were observed in rats of the GnRH2-MAP group. Thus, GnRH2-MAP may be an effective antigen and a potential immunocastration vaccine with higher effectiveness.
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Affiliation(s)
- Zhiqiu Yao
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Wenyu Si
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Weiguo Tian
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Jing Ye
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Rongfei Zhu
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Xiumei Li
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Shichun Ji
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Qianqian Zheng
- Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Ya Liu
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China
| | - Fugui Fang
- Anhui Provincial Key Laboratory of Genetic Resources Protection and Biological Breeding in Local Livestock and Poultry, 130 Changjiang West Road, Hefei, Anhui 230036, China; Department of Animal Veterinary Science, College of Animal Sciences and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui 230036, China.
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Lueders I, Young D, Maree L, van der Horst G, Luther I, Botha S, Tindall B, Fosgate G, Ganswindt A, Bertschinger HJ. Effects of GnRH vaccination in wild and captive African Elephant bulls (Loxodonta africana) on reproductive organs and semen quality. PLoS One 2017; 12:e0178270. [PMID: 28915245 PMCID: PMC5603079 DOI: 10.1371/journal.pone.0178270] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 05/10/2017] [Indexed: 12/04/2022] Open
Abstract
OBJECTIVES Although the African elephant (Loxodonta africana) is classified as endangered by the International Union for Conservation of Nature (IUCN), in some isolated habitats in southern Africa, contraception is of major interest due to local overpopulation. GnRH vaccination has been promoted as a non-invasive contraceptive measure for population management of overabundant wildlife. We tested the efficacy of this treatment for fertility control in elephant bulls. METHODS In total, 17 male African elephants that were treated with a GnRH vaccine were examined in two groups. In the prospective study group 1 (n = 11 bulls, ages: 8-36 years), semen quality, the testes, seminal vesicles, ampullae and prostate, which were all measured by means of transrectal ultrasound, and faecal androgen metabolite concentrations were monitored over a three-year period. Each bull in the prospective study received 5 ml of Improvac® (1000 μg GnRH conjugate) intramuscularly after the first examination, followed by a booster six weeks later and thereafter every 5-7 months. In a retrospective study group (group 2, n = 6, ages: 19-33 years), one examination was performed on bulls which had been treated with GnRH vaccine for 5-11 years. RESULTS In all bulls of group 1, testicular and accessory sex gland sizes decreased significantly after the third vaccination. In six males examined prior to vaccination and again after more than five vaccinations, the testis size was reduced by 57.5%. Mean testicular height and length decreased from 13.3 ± 2.6 cm x 15.2 ± 2.8 cm at the beginning to 7.6 ± 2.1 cm x 10.2 ± 1.8 cm at the end of the study. Post pubertal bulls (>9 years, n = 6) examined prior to vaccination produced ejaculates with viable spermatozoa (volume: 8-175 ml, sperm concentration: 410-4000x106/ml, total motility: 0-90%), while after 5-8 injections, only 50% of these bulls produced ejaculates with a small number of immotile spermatozoa. The ejaculates of group 2 bulls (vaccinated >8 times) were devoid of spermatozoa. Faecal androgen metabolite concentrations measured in captive males decreased significantly after the fourth vaccination. None of the males entered musth during the treatment period. CONCLUSIONS Our results showed a marked decrease in semen quality, testicle and secondary sex gland sizes following repeated GnRH vaccinations. After 2-4 years of continuous treatment every 5-7 months, the effects were similar to surgical castration.
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Affiliation(s)
- Imke Lueders
- GEOlifes-Animal Fertility and Reproductive Research, Frohmestr. 7, Hamburg, Germany
- Endocrine Research Laboratory, Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Debbie Young
- African Elephant Research Unit, Plettenberg Bay, South Africa
| | - Liana Maree
- Department of Medical Biosciences, University of the Western Cape, Bellville, South Africa
- Department of Research and Scientific Services, National Zoological Gardens of South Africa, Pretoria, South Africa
| | - Gerhard van der Horst
- Department of Medical Biosciences, University of the Western Cape, Bellville, South Africa
- Department of Research and Scientific Services, National Zoological Gardens of South Africa, Pretoria, South Africa
| | - Ilse Luther
- Department of Medical Biosciences, University of the Western Cape, Bellville, South Africa
- Department of Research and Scientific Services, National Zoological Gardens of South Africa, Pretoria, South Africa
| | | | - Brendan Tindall
- Robberg Veterinary Clinic, 56 Longships, Plettenberg Bay, South Africa
| | - Geoffrey Fosgate
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - André Ganswindt
- Endocrine Research Laboratory, Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Henk J. Bertschinger
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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Hirsbrunner G, Rigert S, Janett F, Hüsler J, Schnydrig P, Lopez E, Amatayakul-Chantler S, Steiner A. Immunization against GnRF in adult cattle: a prospective field study. BMC Vet Res 2017; 13:208. [PMID: 28666431 PMCID: PMC5493852 DOI: 10.1186/s12917-017-1129-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 06/22/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Suppression of cyclic activity in cattle is often desired in alpine farming and for feedlot cattle, not intended for breeding. A cattle specific anti-GnRF vaccine (Bopriva™) is registered for use in heifers and bulls in different countries. In adult cows vaccinated with Bopriva™, the median period until recurrence of class III follicles was 78 days from the day of the 2nd vaccination and reversibility could be proven, as out of 11 experimental cows 10 cows became pregnant at first, and one cow at second insemination. In the present study, 76 healthy, cyclic Eringer heifers and cows were vaccinated twice with Bopriva™ 3-7 weeks apart, to prevent estrus during alpine pasturing. Blood samples were taken for progesterone and GnRF antibody titer analysis on the day of inclusion (7-9 d before the first vaccination) and at the first vaccination. At the same time, gynaecological examinations were performed. When estrus occurred in the course of the alpine pasturing season, a gynaecological examination was done including analysis of a blood sample (progesterone, anti-GnRF antibody titer). Cows were followed for fertility out to 26 months post second vaccination. RESULTS Median duration of estrus suppression was 191 days after the second vaccination (when the 2 vaccinations were given 28-35 days apart). From n = 13 cows showing signs of estrus on the alpine pasture, n = 7 could not be confirmed in estrus (serum progesterone value >2 ng/ml, no class III follicles seen using ultrasonography). Median duration between second vaccination and next calving was 496 days (25%/75% quartiles: 478/532 days). CONCLUSION Bopriva™ induced a reliable and reversible suppression of estrus for more than 3 months in over 90% of the cows.
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Affiliation(s)
- Gaby Hirsbrunner
- Clinic for Ruminants, Vetsuisse Faculty, University of Berne, Bremgartenstrasse 109a, CH-3012, Berne, Switzerland.
| | - Sarah Rigert
- Tierarztpraxis Arche, CH-3952, Susten, Switzerland
| | - Fredi Janett
- Department of Farm Animals, Vetsuisse-Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057, Zurich, Switzerland
| | - Jürg Hüsler
- Institute of Mathematical Statistics and Actuarial Science, Sidlerstrasse 5, CH-3012, Berne, Switzerland
| | - Philipp Schnydrig
- Institut for Veterinary Bacteriology, Länggassstrasse 122, CH-3012, Berne, Switzerland
| | - Ester Lopez
- Zoetis Research and Manufacturing, 45 Poplar Road, Parkville, VIC, A-3052, Australia
| | | | - Adrian Steiner
- Clinic for Ruminants, Vetsuisse Faculty, University of Berne, Bremgartenstrasse 109a, CH-3012, Berne, Switzerland
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