Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-28T09:49:42.490Z Has data issue: false hasContentIssue false
  • English
  • Français

Extending the interval between second vaccination and slaughter: II. Changes in the reproductive capacity of immunocastrated ram lambs

Published online by Cambridge University Press:  17 January 2019

T. Needham Open the ORCID record for T. Needham [Opens in a new window] ,
H. Lambrechts  and
L. C. Hoffman
T. Needham
Affiliation:
Department of Animal Sciences, University of Stellenbosch, Private Bag X1, Matieland, Stellenbosch7602, South Africa Department of Animal Science and Food Processing, Faculty of Tropical AgriSciences, Czech University of Life Sciences Prague, Kamýcká 961/129, Prague165 00, Czech Republic
H. Lambrechts
Affiliation:
Department of Animal Sciences, University of Stellenbosch, Private Bag X1, Matieland, Stellenbosch7602, South Africa
L. C. Hoffman*
Affiliation:
Department of Animal Sciences, University of Stellenbosch, Private Bag X1, Matieland, Stellenbosch7602, South Africa Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Health and Food Sciences Precinct, 39 Kessels Rd, Coopers Plains4108, QLD, Australia
*
†E-mail: [email protected]
Get access

Abstract

Immunocastration improves the welfare of castrated commercial slaughter lambs; however, the time-point at which this technique influences semen quality and sperm production has not yet been established for various vaccination schedules. Furthermore, the effect of extended intervals between second vaccination and slaughter needs to be investigated regarding continued testosterone suppression in immunocastrated lambs. The effect of extending the interval between second immunocastration vaccination and slaughter from four to six weeks on the reproductive capacity of Dohne Merino lambs was examined. A total of 40 Dohne Merino lambs were stratified according to initial weight (45.4±3.68 kg) and randomly assigned to four treatments that included intact control rams (R), Burdizzo-castrated lambs (B) and lambs immunocastrated with either four (ICS4) or six (ICS6) weeks between second vaccination and slaughter. Blood and semen samples were collected throughout the study period to determine serum testosterone concentrations, evaluate semen quality and assess sperm viability. Semen samples from R showed improvement over the trial. Throughout the collection period, B lambs had low serum testosterone concentrations, poor sperm motility and sperm viability, as expected. However, a slight increase in the percentage of live sperm in semen samples from B lambs towards the end of the collection period indicated poor success rates of the technique in some lambs. Burdizzo-castration also caused testes tissue necrosis and abscessing, indicating physiological stress. Semen appearance scores varied for both immunocastrated treatments, but the mass motility scores decreased over time. The ICS6 lambs showed a consistent and continuous decline in serum testosterone concentrations and sperm viability, with an increased percentage of dead abnormal sperm in the semen samples at the end of the study. The ICS4 treatment was successful in interrupting serum testosterone production and reducing semen quality; however, not as consistently as the ICS6 treatment. Primary immunocastration vaccination influenced serum testosterone concentrations but consistently low levels were only realised for both treatments after secondary vaccination. Although all castration treatments influenced testes size and colour, the six-week vaccination-to-slaughter interval caused a greater decrease in testes cut surface L* (lightness) colour values and in seminiferous tubule circumference. Extending the interval between second immunocastration vaccination and slaughter resulted in a more consistent and reliable influence on reproductive capacity of immunocastrated lambs. Thus, immunocastration is a suitable alternative to Burdizzo-castration regarding the interruption of testosterone production and testis functioning.

Keywords

electro-ejaculationBurdizzogonadotropin-releasing hormonesheeptestes
Type
Research Article
Information
animal , Volume 13 , Issue 9 , September 2019 , pp. 1962 - 1971
Copyright
© The Animal Consortium 2019 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bai, M, Sun, L, Zhao, J, Xiang, L, Cheng, X, Li, J, Jia, C and Jiang, H 2017. Histological analysis and identification of spermatogenesis-related genes in 2-, 6-, and 12-month-old sheep testes. The Science of Nature. 104, 1–13.CrossRefGoogle Scholar
Bedford-Guaus, S 2016. Breeding soundness examination of rams. Retrieved on 9 October 2017 from http://www.msdvetmanual.com/management-and-nutrition/breeding-soundness-examination-of-the-male/breeding-soundness-examination-of-rams.Google Scholar
D’Occhio, M and Brooke, D 1982. Threshold of plasma testosterone required for normal mating activity in male sheep. Hormones and Behaviour 16, 383–394.CrossRefGoogle ScholarPubMed
Gofur, M, Hossain, K, Khaton, R and Hasan, M 2014. Effect of testosterone on physio-biochemical parameters and male accessory sex glands of black Bengal goat. International Journal of Emerging Technology and Advanced Engineering 9, 456–465.Google Scholar
Gökdal, Ö, Atay, O, Ülker, H, Kayaardi, S, Kanter, M, de Avila, M and Reeves, J 2010. The effects of immunological castration against GnRH with recombinant OL protein (ovalbumin-LHRH-7) on carcass and meat quality characteristics, histological appearance of testes and pituitary gland in Kivircik male lambs. Meat Science 86, 692–698.CrossRefGoogle ScholarPubMed
Hafez, B and Hafez, E 2008. Reproduction in farm animals, 7th edition. Wiley-Blackwell, Indianapolis, IN, USA.Google Scholar
Hosie, B, Carruthers, J and Shepard, B 1992. Lamb castration: some practical considerations. Proceedings of the Sheep Veterinary Society 16, 93–95.Google Scholar
Janett, J, Lanker, U, Jörg, H, Hässig, M and Thun, R 2003. Die Kastration männlicher Lämmer mittels Immunisierung gegen GnRH. Schweizer Archiv für Tierheilkunde 145, 291–299. in German.CrossRefGoogle Scholar
Kiyma, Z, Adams, T, Hess, B, Riley, M, Murdoch, W and Moss, G 2000. Gonadal function, sexual behaviour, feedlot performance, and carcass traits of ram lambs actively immunised against GnRH. Journal of Animal Science 78, 2237–2243.CrossRefGoogle Scholar
Lealiifano, A, Pluske, J, Nicholls, R, Dunshea, F, Campbell, R, Hennessy, D, Miller, D, Hansen, C and Mullan, B 2011. Reducing the length of time between slaughter and the secondary gonadotropin-releasing factor immunization improves growth performance and clears boar taint compounds in male finishing pigs. Journal of Animal Science 89, 2782–2792.CrossRefGoogle ScholarPubMed
Martins, M, Gonçalves, M, Tavares, K, Gaudêncio, S, Santos Neto, P, Dias, A, Gava, A, Saito, M, Oliveira, C, Mezzalira, A and Vieira, A 2011. Castration methods do not affect weight gain and have diverse impacts on the welfare of water buffalo males. Livestock Science 140, 171–176.CrossRefGoogle Scholar
Melches, S, Mellema, S, Doherr, M, Wechsler, B and Steiner, A 2007. Castration of lambs: A welfare comparison of different castration techniques in lambs over 10 weeks of age. Veterinary Journal 173, 554–563.CrossRefGoogle ScholarPubMed
Needham, T, Lambrechts, H and Hoffman, L 2016. The influence of vaccination interval on growth, carcass traits and testicle parameters of immunocastrated ram lambs. Small Ruminant Research 145, 53–57.CrossRefGoogle Scholar
Needham, T, Lambrechts, H and Hoffman, L 2017. Castration of male livestock and the potential of immunocastration to improve animal welfare and production traits: Invited Review. South African Journal of Animal Science 47, 731–742.CrossRefGoogle Scholar
Needham, T, Lambrechts, H and Hoffman, L 2019. Influence of immunocastration vaccine administration interval on serum androgen concentrations and testis activity in ram lambs. Small Ruminant Research 170, 82–90.CrossRefGoogle Scholar
Quanson, J, Stander, M, Pretorius, E, Jenkinson, C, Taylor, A and Storbeck, K 2016. High-throughput analysis of 19 endogenous androgenic steroids by ultra-performance convergence chromatography tandem mass spectrometry. Journal of Chromatography B 1031, 131–138.CrossRefGoogle Scholar
Ramsem 2017. Semen collection. Retrieved on 16 October 2017 from http://www.ramsem.com/semen_collection.php.Google Scholar
Rouge, M 2004a. Counting cells with a hemacytometer. Retrieved on 20September 2017 from http://www.vivo.colostate.edu/hbooks/pathphys/reprod/semeneval/hemacytometer.html.Google Scholar
Rouge, M 2004b. Sperm morphology. Retrieved on 20 September 2017 from http://www.vivo.colostate.edu/hbooks/pathphys/reprod/semeneval/morph.html.Google Scholar
Thompson, D 2000. Immunization against GnRH in male species (comparative aspects). Animal Reproduction Science 60-61, 459–469.CrossRefGoogle Scholar
Ülker, H, Gökdal, Ö, Temur, C, Budağ, C, Oto, M, de Avila, D and Reeves, J 2002. The effect of immunization against LHRH on body growth and carcass characteristics in Karakas ram lambs. Small Ruminant Research 45, 273–278.CrossRefGoogle Scholar
Ülker, H, Kanter, M, Gökdal, Ö, Aygün, T, Karakus, F, Sakarya, M, De Avila, D and Reeves, J 2005. Testicular development, ultrasonographic and histological appearance of the testis in ram lambs immunized against recombinant LHRH fusion proteins. Animal Reproduction Science 86, 205–219.CrossRefGoogle ScholarPubMed
Ülker, H, Küçük, M, Yilmaz, A, Yörük, M, Arslan, L, deAvila, D and Reeves, J 2009. LHRH fusion protein immunization alters testicular development, ultrasonographic and histological appearance of ram testis. Reproduction in Domestic Animals 44, 593–599.CrossRefGoogle ScholarPubMed
Zoetis (Pfizer Animal Health) 2010. Transform bull management with Bopriva: Veterinary Guide. Retrieved on 16 October 2017 from http://www.zoetis.co.nz/_locale-assets/doc/species-products/bopriva-veterinary-guide.pdf.Google Scholar
Supplementary material: File

Needham et al. supplementary material

Table S1 and Figures S1-S2

Download Needham et al. supplementary material(File)
File 189.5 KB