Analyze Diet
Zoo biology2007; 26(4); 237-244; doi: 10.1002/zoo.20109

Immunocontraception and increased longevity in equids.

Abstract: Intensive population management by means of fertility control has been shown to change the age profile of a wild horse herd. The primary change has been an increase in the number and percent of older animals, as expected, but also the appearance of new and older age classes. An examination of direct effects of fertility control on two groups of treated animals shows a significant increase in longevity over non-treated animals that is associated with contraceptive treatment. The mean age at death (MAD) was calculated for 128 wild horses for which precise birth and death dates were known, including 56 stallions, 42 untreated mares, 11 mares treated with a porcine zona pellucida contraceptive vaccine for 1-2 years, and 19 mares treated with the same vaccine for >/=3 years. The MAD for stallions (10.3+/-0.84 [SEM] years), and mares treated for 1-2 years (10.2+/-0.56), was significantly greater (P<0.05) than for untreated mares (6.4+/-0.85), and significantly /=3 years (19.9+/-1.66). Zoo Biol 26:237-244, 2007. (c) 2006 Wiley-Liss, Inc.
Publication Date: 2007-07-01 PubMed ID: 19360577DOI: 10.1002/zoo.20109Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research investigates the impact of immunological infertility control, known as immunocontraception, on equine longevity and population age dynamics, finding that its use does increase the lifespan of treated horses and creates older age classes in herds.

Context and Methodology

  • The researchers aimed to explore the impact of intensive population management through fertility control on the age structure of a wild horse herd.
  • This study used the age and survival data of 128 horses, a mixture of stallions, treated and untreated mares.
  • Of these, some mares were treated with a contraceptive vaccine derived from pig egg covering (commonly known as porcine zona pellucida – PZP) for either 1-2 years or for at least 3 years.

Main Findings

  • One of the main findings showed an increase in the number of older animals within the herd, representing a shift in the age structure as a result of fertility control.
  • Alongside this, the study observed the development of new and older age groups, suggesting the emergence of age classes that may previously have been absent or few in number.
  • The contraceptive treatment significantly increased horse longevity. This is reflected in the Mean Age at Death (MAD) calculations, where treated mares appeared to live longer compared to untreated ones and stallions.
  • Specifically, stallions and mares treated for 1-2 years had a MAD of 10.3 and 10.2 respectively, whereas untreated mares had a significantly lower MAD of 6.4.
  • Mares treated with the contraceptive for at least 3 years exhibited the highest MAD at 19.9, almost doubling the lifespan of untreated mares.

Implications

  • These findings can aid in understanding the long-term impacts of fertility control on wildlife populations, specifically equids or horse-like animals.
  • Besides influencing age structure within herds, fertility control, in this case immunocontraception, contributed to an increase in horse lifespan. This discovery can be useful for population management strategising.
  • The results may lead to the implementation of fertility control as a regular management strategy for wild horse herds as it promotes the health and welfare of individual horses and maintains a balanced age distribution within the population.

Cite This Article

APA
Kirkpatrick JF, Turner A. (2007). Immunocontraception and increased longevity in equids. Zoo Biol, 26(4), 237-244. https://doi.org/10.1002/zoo.20109

Publication

ISSN: 1098-2361
NlmUniqueID: 8807837
Country: United States
Language: English
Volume: 26
Issue: 4
Pages: 237-244

Researcher Affiliations

Kirkpatrick, Jay F
  • The Science and Conservation Center, Billings, Montana.
Turner, Allison

    Citations

    This article has been cited 3 times.
    1. Harvey AM, Ramp D, Mellor DJ. Review of the Foundational Knowledge Required for Assessing Horse Welfare.. Animals (Basel) 2022 Dec 1;12(23).
      doi: 10.3390/ani12233385pubmed: 36496906google scholar: lookup
    2. Kuninaga N, Asano M, Matsuyama R, Minemoto T, Mori T, Suzuki M. Serological and histological evaluation of species-specific immunocontraceptive vaccine antigens based on zona pellucida 3 in the small Indian mongoose (Herpestes auropunctatus).. J Vet Med Sci 2019 Feb 28;81(2):328-337.
      doi: 10.1292/jvms.17-0605pubmed: 30587673google scholar: lookup
    3. Ransom JI, Powers JG, Thompson Hobbs N, Baker DL. Ecological feedbacks can reduce population-level efficacy of wildlife fertility control.. J Appl Ecol 2014 Feb;51(1):259-269.
      doi: 10.1111/1365-2664.12166pubmed: 25558083google scholar: lookup