Social behavior and welfare in horses (Equus caballus)

Thaana Van Dessel
Bachelorproef over sociaal gedrag bij paarden, met een specifieke nadruk op dominantie, agressie, vriendschappen (affiliaties) en ruimtelijke posities binnen de groep. Alsook onderzoek naar de effecten van het gebrek aan sociaal contact in de vorm van sociale isolatie.

Het verborgen leed van paarden

De laatste vijftig jaar is er een toename van het aantal mensen met paarden en een afname van het aantal paardenmensen.

Paarden maken al eeuwen deel uit van onze maatschappij, en nu is de paardensport nog populairder dan ooit. Maar hoe goed kennen we onze paarden eigenlijk? En in hoeverre weten we wel of ze gelukkig zijn? Hoe ervaren zij het leven dat we hun opleggen?

Ten einde het paard en zijn welzijnsnoden beter te begrijpen, heb ik tussen februari en mei 2018 een onderzoek gedaan naar het natuurlijk kuddegedrag van paarden, en naar de effecten van sociale isolatie. Het ultieme doel was om de ware aard van het paard naar voren te brengen, met als hoop dat de opgedane kennis een betere toekomst zou beteken voor gedomesticeerde paarden.
In de studie werden er twee onderzoekspopulaties ingezet: een kudde van veertien Akhal-Teke paarden, gehouden op 40 hectaren land in het Zuiden van Estland en een groep van negen IJslandse paarden gehuisvest op een paddock met inloopstal te Stabroek, België.

Resultaten

Vriendschap

De resultaten toonden dat paarden hoog sociale dieren zijn die frequent contact zoeken met hun kuddemaatjes. Zo zullen paarden elkaar krabben en poetsen, dicht bij elkaar gaan staan om te rusten of samen spelen. Bovendien nemen paarden van alle rang- en leeftijdscategorieën deel aan deze sociale interacties, wat betekend dat sociaal contact voor alle individuen zeer belangrijk is. Verder hebben we ondervonden dat paarden ook hechte vriendschappen vormen, in beide kuddes waren er meerdere duo’s die veel meer met elkaar omgingen dan met andere kuddeleden, bovendien waren deze ‘beste maatjes’ steeds van gelijke rangorde (bv. 1ste en 2de ; 12de en 13de in rang). En zowel hoog- als laag rankende paarden toonden de behoefte om hechte banden te vormen met andere paarden.

Isolatie

Tijdens de isolatie-test hebben we elke IJslander gedurende vijf minuten alleen op stal gezet. De afzondering wekte extreme stressreacties op, de dieren toonden allen signalen van abnormale spanning, angst en frustratie. Ze begonnen rusteloos over en weer te lopen, angstig rond te kijken, luid te briesen en te mesten. Sommige paarden probeerden de deur te forceren, anderen sloegen heftig tegen de grond met hun hoeven of begonnen in het rond te bokken. Zulke reacties ondanks het feit dat de afzondering enkel een paar minuten duurde vertalen ernstige stress en tonen aan dat sociale isolatie zware gevolgen kan hebben op de gemoedstoestand en het welzijn van paarden.

Groupshuisvesting, maar hoe? 

Als paarden niet geschikt zijn om een solitair leven te leiden, dan moeten ze wel in groep gehouden worden, maar op welke manier? Veel eigenaars houden hun (soms heel dure) paarden liever apart omdat ze ervan overtuigd zijn dat paarden onderling veel agressie naar elkaar tonen en dat er dus hoge kansen zijn op verwonding. Onze studie (en andere voorheen) toont echter dat paarden die in stabiele kuddes leven, vooral communiceren aan de hand van subtiele signalen en dat dominantie en agressie hoofdzakelijk worden geuit door dreigingen en neutrale benaderingen. Werkelijke contact-agressie (zoals bijten of schoppen) die zou kunnen resulteren in verwonding, vertegenwoordigde enkel 5% van alle agressieve gedragingen onder onze Akhal-Teke paarden. Dit was echter hoger bij de IJslanders (15%), en we hebben ondervonden dat de mate van agressie in een kudde sterk afhankelijk is van het menselijk beheer, van “hoe de paarden gehouden worden”. Zo kunnen er meerdere factoren inspelen op agressie:

Leefruimte

De contact-agressie was drie keer hoger (15% vs. 5%) in de kudde die op een kleiner oppervlak werd gehouden. Bovendien suggereren onze resultaten dat deze paddock-paarden veel meer agressie toonden in de context van ruimteverdediging dan de paarden die gehuisvest waren op een weide van 40ha. We vermoeden dus dat de factor omvang van leefruimte een considerabele rol speelt in de toename (of afname) van agressief gedrag. We hebben tevens ook gevonden dat ondergeschikte paarden meestal in periferie van de kudde bleven en dat anciënniteit gelinkt was aan rangorde, nieuwkomers zouden steeds een lage positie krijgen in de hiërarchie.
Onze resultaten wijzen er dus op dat – om agressie te verlagen en een goed welzijn te bekomen – elk individu over voldoende ruimte moet beschikken om zich te kunnen terugtrekken bij confrontaties en om zijn gewenste (en natuurlijke) interindividuele afstand te houden t.o.v. andere kudde leden. We suggereren ook dat er extra aandacht moet gegeven worden bij het introduceren van nieuwe paarden, en dat dit enkel gedaan mag worden wanneer er voldoende bewegingsruimte is voor de groep. In dit licht is het ook niet aangeraden om paarden regelmatig van groep te veranderen of “nu en dan” eens in een kudde te zetten.

Akhal-Teke paarden, Estland

Voedsel

In het wild foerageren paarden 60% - 70% van de dag. Onze kuddes, die quasi continu hooi ter beschikking hadden, aten gemiddeld 55% van de tijd dat ze geobserveerd werden, en op alle tijdstippen van de dag. Wat aantoont dat paarden in gevangenschap gelijke voederbehoeften hebben aan die van hun wilde soortgenoten. Ondanks de abundantie aan voedsel werd de meerderheid van agressief gedrag toch geuit in de context van voedsel(competitie), dit zou veroorzaakt kunnen zijn door de verspreiding van het voedsel: de onnatuurlijke opeenhoping zou de drang tot competitie en monopolisering van voedselbronnen opwekken waardoor hogere agressie geobserveerd wordt. Bijgevolg stellen we voor dat voedsel best op meerdere plaatsen wordt verspreid.

Wat kunnen we hieruit begrijpen?

De studie heeft aangetoond dat paarden hoog sociale dieren zijn die sterke vriendschapsbanden met elkaar vormen en acute stressreacties tonen wanneer ze worden geïsoleerd. Dit wijst erop dat paarden alleen houden ernstige gevolgen kan hebben voor hun welzijn. Bovendien blijkt dat leefruimte en voedselbeschikbaarheid zeer belangrijke factoren zijn voor kuddebeheer, gebrekkig management kan namelijk verhoogde stresslevels en onnodige conflicten veroorzaken.
We sluiten het artikel met een aantal welzijnssuggesties: 1) hou uw paard niet alleen 2) als u paard in groep leeft, geef dan de voorkeur aan a/ een ruime leefomgeving, b/een constante aanwezigheid van ruwvoer dat op verschillende plekken wordt verspreid en c/ aan minimale veranderingen in de samenstelling van de kudde.

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Universiteit of Hogeschool
Agro- en biotechnologie
Publicatiejaar
2018
Promotor(en)
Hilde Vervaecke
Kernwoorden
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