Register      Login
Animal Production Science Animal Production Science Society
Food, fibre and pharmaceuticals from animals
RESEARCH ARTICLE

Immunisation against gonadotrophin-releasing hormone (GnRH) increases growth and reduces variability in group-housed boars

F. R. Dunshea A B I , G. M. Cronin B C , J. L. Barnett A B , P. H. Hemsworth A B , D. P. Hennessy D , R. G. Campbell E , B. Luxford F , R. J. Smits F , A. J. Tilbrook G , R. H. King A B and I. McCauley H
+ Author Affiliations
- Author Affiliations

A Melbourne School of Land and Environment, The University of Melbourne, Melbourne, Vic. 3010, Australia.

B Formerly Department of Primary Industries, 600 Sneydes Road, Werribee, Vic. 3030, Australia.

C Faculty of Veterinary Science, The University of Sydney, Camden, NSW 2570, Australia.

D Pfizer Animal Health, Poplar Road, Parkville, Vic. 3052, Australia.

E Pork Cooperative Research Centre, Roseworthy Campus, The University of Adelaide, SA 5371, Australia.

F Rivalea Australia, Corowa, NSW 2646, Australia.

G Department of Physiology, Monash University, Clayton, Vic. 3800, Australia.

H Department of Primary Industries, Mickleham Road, Attwood, Vic. 3049, Australia.

I Corresponding author. Email: fdunshea@unimelb.edu.au

Animal Production Science 51(8) 695-701 https://doi.org/10.1071/AN11021
Submitted: 16 February 2011  Accepted: 27 May 2011   Published: 5 August 2011

Abstract

It is generally accepted that entire boars are leaner and more efficient than barrows but that they have poorer meat quality with an increased risk of boar taint. An additional issue in producing boars to meet market specifications is variation in growth performance, which may be exacerbated by high levels of aggression and mounting behaviour in group-housed animals. Immunisation against gonadotrophin-releasing hormone (GnRH), leading to immunological castration, offers a means of reducing aggression and mounting behaviour while maintaining most of the production efficiencies associated with entire boars. A total of 120 control boars, 120 immunised boars and 60 barrows (physically castrated at 5 days of age) were used in a study conducted in two replicates. Each replicate consisted of two pens each of boars, immunised boars and barrows, each pen containing 15 pigs, and two blocks of 15 individually-housed boars and immunised boars. The group-housed pigs had access to two single place electronic feeders per pen. Immunised boars were given the anti-GnRH vaccine (Improvac) at 14 and 18 weeks of age. In the 2 weeks immediately after the secondary immunisation at 18 weeks, average daily gain was greater in the immunised boars than the boars or barrows, particularly in those that were group housed, as indicated by the interaction (P = 0.035). From 18 to 23 weeks of age average daily gain was greater (P = 0.005) in immunised boars than in control boars and barrows and was greater (P < 0.001) in individually- than in group-housed pigs. The average daily gain of group-housed immunised boars and individually-housed control boars were similar over the 5-week period after secondary immunisation (1090 vs 1099 g/day), being ~20 and 15% higher than the group-housed control boars and barrows, respectively. The average daily feed intake was greater (P = 0.011) in immunised boars than in control boars with barrows intermediate. The standard deviation of bodyweight increased with age but was lower (P from 0.032 to 0.09) in immunised boars than in control boars and barrows between 18 and 22 and 17 and 21 weeks of age. Carcass fighting damage and pork pH were higher (P < 0.05) for control boars than for immunised boars or barrows. In conclusion, immunisation against GnRH increased average daily gain and average daily feed intake while decreasing variation in bodyweight and improving carcass and pork quality.


References

Allison J, McKeith F, Souza C, Boler D, Killefer J, Hennessy D (2009a) Impact of using vaccination with Improvac rather than physical castration on the objective meat quality of finishing male pigs. In ‘The 55th international congress of meat science and technology (ICoMST). 16–21 August 2009, Copenhagen, Denmark’. pp. 1227–1229.

Allison J, McKeith F, Souza C, Boler D, Killefer J, Hennessy D (2009b) Impact of using vaccination with Improvac on the sensory perception of meat from finishing male pigs. In ‘The 55th international congress of meat science and technology (ICoMST). 16–21 August 2009, Copenhagen, Denmark’. pp. 1234–1236.

Anonymous (2007) ‘Model Code of Practice for the Welfare of Animals – pigs (Revised). Primary Industries Ministerial Council.’ (CSIRO Publishing: Melbourne)

Baumgartner J, Laister S, Koller M, Pfutzner A, Grodzycki M, Andrews S, Schmoll F (2010) The behaviour of male fattening pigs following either surgical castration or vaccination with a GnRF vaccine. Applied Animal Behaviour Science 124, 28–34.
The behaviour of male fattening pigs following either surgical castration or vaccination with a GnRF vaccine.Crossref | GoogleScholarGoogle Scholar |

Bonneau M (1982) Compounds responsible for boar taint, with special emphasis on androstenone: a review. Livestock Production Science 9, 687–705.
Compounds responsible for boar taint, with special emphasis on androstenone: a review.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL3sXhtVGktrw%3D&md5=a0b1b68fac57412358a2c49babdd94adCAS |

Campbell RG, Taverner MR (1988) Genotype and sex effects on the relationship between energy intake and protein deposition in growing pigs. Journal of Animal Science 66, 676–686.

Cronin GM, Dunshea FR, Butler KL, McCauley I, Barnett JL, Hemsworth PH (2003) The effects of immuno- and surgical-castration on the behaviour and consequently growth of group-housed, male finisher pigs. Applied Animal Behaviour Science 81, 111–126.
The effects of immuno- and surgical-castration on the behaviour and consequently growth of group-housed, male finisher pigs.Crossref | GoogleScholarGoogle Scholar |

de Haer LCM, de Vries AG (1993) Feed intake patterns and digestibility in growing pigs housed individually or in groups. Livestock Production Science 33, 277–292.
Feed intake patterns and digestibility in growing pigs housed individually or in groups.Crossref | GoogleScholarGoogle Scholar |

Dunshea FR (2007) Castration in the swine industry – why is it done and what does it cost in terms of lost production. In ‘Congress of the Asian Pig Veterinary Society, Vol. 3’. pp. 80–86. (Wuhan, China)

Dunshea FR, King RH, Campbell RG, Sainz RD, Kim YS (1993) Interrelationships between sex and ractopamine on protein and lipid deposition in rapidly growing pigs. Journal of Animal Science 71, 2919–2930.

Dunshea FR, Eason PJ, King RH, Campbell RG (1998) Interrelationships between dietary ractopamine, dietary energy and sex on protein and fat deposition in growing pigs. Australian Journal of Agricultural Research 49, 565–574.
Interrelationships between dietary ractopamine, dietary energy and sex on protein and fat deposition in growing pigs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXjtVSjtL0%3D&md5=ec9d894a5d87e8b04287e18a5029462bCAS |

Dunshea FR, Colantoni C, Howard K, Jackson P, Long KA, Lopaticki S, Nugent EA, Simons JA, Walker J, Hennessy DP (2001) Vaccination of boars with a GnRH vaccine (Improvac) eliminates boar taint and increases growth performance. Journal of Animal Science 79, 2524–2535.

Fàbrega E, Velarde A, Cros J, Gispert M, Suarez P, Tibau J, Soler J (2010) Effect of vaccination against gonadotrophin-releasing hormone, using Improvac, on growth performance, body composition, behaviour and acute phase proteins. Livestock Science 132, 53–59.
Effect of vaccination against gonadotrophin-releasing hormone, using Improvac, on growth performance, body composition, behaviour and acute phase proteins.Crossref | GoogleScholarGoogle Scholar |

Fredriksen B, Nafstad O (2006) The Norwegian research programme for entire male pig production. Acta Veterinaria Scandinavica 48, S16
The Norwegian research programme for entire male pig production.Crossref | GoogleScholarGoogle Scholar |

Hansson I (1974) Effect of sex and weight on growth, feed efficiency and carcass characteristics of pigs. 1. Growth rate and feed efficiency of boars, barrows and gilts. Swedish Journal of Agricultural Research 4, 214–218.

Horgan R (2006) Piglet castration and EU animal welfare legislation. Acta Veterinaria Scandinavica 48, S2
Piglet castration and EU animal welfare legislation.Crossref | GoogleScholarGoogle Scholar |

Judge MD, Mills EW, Orcutt MW, Forrest JC, Diekman MA, Harmon BG, Lin RS, Nicholls LL (1990) Utilization of boar meat: composition, quality and odor incidence in relation to androstenone and skatole. Journal of Animal Science 68, 1030–1033.

Keeler GL, Tokach MD, Goodband RD, Nelssen JL, Langemeir MR (1994) Assisting swine producers to maximize marketing returns. Journal of Extension 32, http://www.joe.org/joe/1994june/a7.php

McCauley I, Watt M, Suster D, Kerton DJ, Oliver WT, Harrell RJ, Dunshea FR (2003) A GnRH vaccine (Improvac) and porcine somatotropin (Reporcin) have synergistic effects upon growth performance in both boars and gilts. Australian Journal of Agricultural Research 54, 11–20.
A GnRH vaccine (Improvac) and porcine somatotropin (Reporcin) have synergistic effects upon growth performance in both boars and gilts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXhs1yntrY%3D&md5=850771f97b23ca7de1495d3916b0f004CAS |

Moeller SJ, Miller RK, Edwards KK, Zerby HN, Logan KE, Aldredge TL, Stahl CA, Boggess M, Box-Steffensmeier JM (2010) Consumer perceptions of pork eating quality as affected by pork quality attributes and end-point cooked temperature. Meat Science 84, 14–22.
Consumer perceptions of pork eating quality as affected by pork quality attributes and end-point cooked temperature.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BC3c3ks1Wnsw%3D%3D&md5=be91e67feebf80b6a5d50654c6cc7b0cCAS |

Monod H, Bailey RA (1992) Pseudofactors – normal use to improve design and facilitate analysis. Journal of the Royal Statistical Society: Series C (Applied Statistics) 41, 317–336.

Moore KL, Dunshea FR, Mullan BP, Hennessy DP, D’Souza DN (2009) Ractopamine supplementation increases lean deposition in entire and immunocastrated male pigs. Animal Production Science 49, 1113–1119.
Ractopamine supplementation increases lean deposition in entire and immunocastrated male pigs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsVWqtLnL&md5=57bb22c3396edf3f6501c89c232badcfCAS |

Morales J, Gispert M, Hortos M, Pérez J, Suárez P, Piñeiro C (2010) Evaluation of production performance and carcass quality characteristics of boars immunised against gonadotropin-releasing hormone (GnRH) compared with physically castrated male, entire male and female pigs. Spanish Journal of Agricultural Research 8, 599–606.

Oliver WT, McCauley I, Harrell RJ, Suster D, Kerton DJ, Dunshea FR (2003) A gonadotropin-releasing factor vaccine (Improvac) and porcine somatotropin have synergistic and additive effects on growth performance in group-housed boars and gilts. Journal of Animal Science 81, 1959–1966.

Patterson DC (1985) A note of the effect of individual penning on the performance of fattening pigs. Animal Production 40, 185–188.
A note of the effect of individual penning on the performance of fattening pigs.Crossref | GoogleScholarGoogle Scholar |

Pauly C, Spring P, O’Doherty JV, Ampuero Kragten S, Bee G (2009) Growth performance, carcass characteristics and meat quality of group-penned surgically castrated, immunocastrated (Improvac®) and entire male pigs and individually penned entire male pigs. Animal 3, 1057–1066.
Growth performance, carcass characteristics and meat quality of group-penned surgically castrated, immunocastrated (Improvac®) and entire male pigs and individually penned entire male pigs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhtVSnsL%2FJ&md5=0a28fb3211e16a4aefa28c2690387600CAS |

Payne HG, Mullan BP, Trezona M, Frey B (1997) A review – variation in pig production and performance. In ‘Manipulating pig production VII’. (Ed. PD Cranwell) pp. 13–26. (Australasian Pig Science Association: Werribee, Vic.)

Rikard-Bell C, Curtis MA, van Barneveld RJ, Mullan BP, Edwards AC, Gannon NJ, Henman DJ, Hughes PE, Dunshea FR (2009) Ractopamine hydrochloride improves growth performance and carcass composition in immunocastrated boars, intact boars, and gilts. Journal of Animal Science 87, 3536–3543.

Rydhmer L, Zamaratskaia G, Andersson HK, Algers B, Guillemet R, Lundstrom K (2006) Aggressive and sexual behaviour of growing and finishing pigs reared in groups, without castration. Acta Agriculturae Scandinavica 56, 109–119.

Rydhmer L, Lundstrom K, Andersson K (2010) lmmunocastration reduces aggressive and sexual behaviour in male pigs. Animal 4, 965–972.
lmmunocastration reduces aggressive and sexual behaviour in male pigs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXlsVOgt7Y%3D&md5=03affdade74806281e22c245a0223634CAS |

Suster D, Leury BJ, Kerton DJ, Borg MR, Butler KL, Dunshea FR (2006) Longitudinal DXA measurements demonstrate lifetime differences in lean and fat tissue deposition in individually penned and group-penned boars and barrows. Australian Journal of Agricultural Research 57, 1009–1015.
Longitudinal DXA measurements demonstrate lifetime differences in lean and fat tissue deposition in individually penned and group-penned boars and barrows.Crossref | GoogleScholarGoogle Scholar |

Wood JD, Riley JE (1982) Comparison of boars and castrates for bacon production. 1. Growth data, and carcass and joint composition. Animal Production 35, 55–63.
Comparison of boars and castrates for bacon production. 1. Growth data, and carcass and joint composition.Crossref | GoogleScholarGoogle Scholar |

Zamaratskaia G, Andersson HK, Chen G, Andersson K, Madej A, Lundstrom K (2008) Effect of a gonadotropin-releasing hormone vaccine (Improvac) on steroid hormones, boar taint compounds and performance in entire male pigs. Reproduction in Domestic Animals 43, 351–359.
Effect of a gonadotropin-releasing hormone vaccine (Improvac) on steroid hormones, boar taint compounds and performance in entire male pigs.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXntFyrsLY%3D&md5=63b2193699303657d5b8e78c92b49bb4CAS |