Comparing and Contrasting Knowledge on Mules and Hinnies as a Tool to Comprehend Their Behavior and Improve Their Welfare

Abstract

Mules and hinnies are the hybrids between donkeys (Equus asinus) and horses (Equus caballus). For centuries, mankind has used them for agrarian purposes, the military, or recreation. Contrasting literature with behavioral observations, we seek a better behavioral understanding andthus comprehensive solutions for their welfare enhancement. Over the past 6 years, we have assessed physical and behavioral welfare in over 900 mules by surveying owners from Egypt, Peru, Portugal, Spain, Mexico, and the U.S. These mules participated in shows, brick kiln work, cart-pulling, packing, tourism, and cattle herding. Observations are discussed alongside facts from the literature. Unfortunately, their behavior has been misunderstood by many, and harsh treatment and equipment has been used to control them. Few studies have attempted to define or use learning theory to understand how and why mules and hinnies behave as they do. Hence, understanding their health considerations, natural behavior, and training theory is crucial for those who work with them.Solutions to welfare improvement partially lie in an individual’s ability to handle mules and hinnies from birth, and to proceed slowly through training. Conclusively, this review sets forth a clearer understanding of these hybrids’ behaviors and promotes positive handling, allowing their access to more routine healthcare and ultimately, a higher welfare standard.

Quantifying poor working equid welfare in Nepalese brick kilns using a welfare assessment tool

“…Hybrids showed the higher number of reactions perceived as more averse. In a study focused on hybrids' behaviour, McLean et al 28 identified that mule owners and handlers find it easier to interact with their animal when compared to allowing a stranger to do so. Therefore, it is possible that the presence of the assessors, assumed as strangers by the mules, explain the results obtained.…”

Perceptions and Attitudes towards Mules in a Group of Soldiers

“…Mules are the least studied equids [ 38 ], but they have gained increasing attention in the scientific literature in the last decade in terms of their physiology and behavior. The aim of adding knowledge about the mule-human interaction is that the present study analyzed attitudes and perceptions of a group of soldiers towards mules.…”

“…For example, in the colonial times in America, the hierarchy between the Spanish elite, Mulato laborers and the indigenous workforce was rendered as an analogy of the hierarchy between horses, mules and donkeys [ 51 ]. In the same line, recent studies show that handlers frequently describe mules as difficult to handle and aggressive [ 18 , 38 , 40 ]. Contrary, in the present study, a negative bias was found for donkeys, and horses were only perceived as more expensive and less aggressive than mules.…”

Comparison of working equid welfare across three regions of Mexico

“…Mules are prized for their strength which is harnessed in agriculture and are preferred over and above horses and donkeys for this ‘heavy work’ such as ploughing, despite their reputation of being temperamentally harder to work with. Negative reactions are particularly seen in response to unfamiliar individuals and have been associated with handling methods 26,27 . Mules are increasing in value as they are becoming more rare and the ability to hire them for agriculture has been highlighted as an important source of income for many owners in Mexico 10 .…”