The validity of behavioural measures of aversion: a review

Welfare aspects of theriogenology: Investigating alternatives to electroejaculation of bulls

Evaluation of the breeding soundness of bulls is an important management tool. Electroejaculation has been a reliable method of obtaining a semen sample for the purpose of evaluating breeding soundness, but is considered by some to be inhumane on the grounds that it is painful. This paper provides a review of studies conducted to find ways to both measure, as well as lessen, pain associated with electroejaculation, and to explore alternatives to electroejaculation in bulls. Changes in heart rate, serum cortisol, serum progesterone, relative aversion, and degrees of vocalization, struggling and lying down have been used to assess the pain associated with electroejaculation. Transrectal massage and artificial vaginas, and oxytocin and cloprostenol have been investigated as alternatives to, and facilitators of electroejaculation, respectively. Epidural, intravenous and topical anesthetics have been used to ameliorate the pain associated with electroejaculation. Serum progesterone and degrees of vocalization are useful for measuring the pain associated with electroejaculation in bulls. Transrectal massage and artificial vaginas are not as efficacious as electroejaculation for obtaining a semen sample and drugs used to facilitate or decrease pain associated with electroejaculation have not been efficacious enough to warrant use. Transrectal massage of the ampullae may be of some use as an alternative to electroejaculation in docile bulls and may be also be used to decrease the duration of subsequent electroejaculation. Pain associated with electroejaculation may be influenced by operator technique; therefore, operators of electroejaculator equipment must strive to apply electrical stimulation as gently as possible.

Behavioral evaluation of the psychological welfare and environmental requirements of agricultural research animals: theory, measurement, ethics, and practical implications

The welfare of agricultural research animals relies not only on measures of good health but also on the presence of positive emotional states and the absence of aversive or unpleasant subjective states such as fear, frustration, or association with pain. Although subjective states are not inherently observable, their interaction with motivational states can be measured through assessment of motivated behavior, which indicates the priority animals place on obtaining or avoiding specific environmental stimuli and thus allows conclusions regarding the impact of housing, husbandry, and experimental procedures on animal welfare. Preference tests and consumer demand models demonstrate that animal choices are particularly valuable when integrated with other behavioral and physiological measurements. Although descriptive assessments of apparently abnormal behavior such as stereotypies and "vacuum behaviors" provide indications of potentially impoverished environments, they should be used with some caution in drawing welfare conclusions. The development of stereotypies may in some cases be linked to psychiatric dysfunction and reflect underlying neurophysiological impairments, which have implications for the ability to perform flexible behavior and thus the quality of research data provided by this kind of behavioral measurement (e.g., in pharmaceutical research). Environmental modifications, commonly termed "enrichment," can have diverse consequences for cognitive function, physiological responses, health, psychological welfare, and research data. Simple practical modifications of housing, husbandry, and experimental design are suggested to improve the psychological welfare of agricultural research animals in accordance with the principles of refining, reducing, and replacing (the "3Rs"), which underlie US Public Health Service Policy, and prevailing public ethics.

Determination of the aversion of farmed mink (Mustela vison) to carbon dioxide

High concentrations of carbon dioxide are commonly used to kill mink before their pelts are removed. The aversiveness of this procedure was investigated by using a passive avoidance technique. Eight mink were trained to obtain a reward (a novel object) by entering a chamber which could be filled with carbon dioxide, as under commercial conditions (over 80 per cent by volume). In the absence of carbon dioxide, mink entered the chamber within a mean (sd) of 16 (2.1) seconds and spent 45 (12) per cent of the next 10 minutes interacting with the novel object. When there was carbon dioxide in the test chamber, the mink would not enter it and coughed and recoiled from the chamber's entrance instead. It was concluded that the mink detected and avoided high concentrations of carbon dioxide, and that if mink are to be killed humanely, less aversive techniques should be used.

The effect of electro-ejaculation on aversive behaviour and plasma cortisol concentration in rams

Electro-ejaculation is used in rams to collect semen for fertility and bacteriological evaluation. Concern has been expressed about animal welfare implications of EE. Two experiments were carried out to compare the aversiveness of electro-ejaculation, part shearing and free movement, and to determine the changes in plasma cortisol concentration produced by electro-ejaculation, shearing and lateral restraint. In the aversion test, transit time was greater (p<0.003) for rams subjected to part shearing than free movement. There were no major differences in the transit time between the rams subjected to electro-ejaculation and those subjected to part shearing or free movement. In addition, there was no significant difference in the effort required to move rams from the three treatment groups into or through the experimental route. These results suggest that electro-ejaculation is no more aversive than part shearing. There were no significant differences in the cortisol response of the rams subjected to electro-ejaculation, shearing or lateral restraint, indicating that there were no significant differences in the distress caused by the three procedures.

Psychologic well-being: conceptual issues, behavioral measures, and implications for dogs

The best means of providing for the physical and psychologic well-being of animals maintained in captive environments for research, teaching, testing, and exhibition is a problem being debated by scientists, veterinarians, animal rights and welfare groups, zoos, and others. Even a cursory examination of this question reveals its complexity and the inherited difficulties not only in assessing an animal's well-being but also in designing housing environments and implementing enforceable regulations. Assessment of well-being should not be based on a single category of measures but rather on a variety of physiologic and behavioral parameters. Most behavioral (and physiologic) methods used to assess well-being have problems of quantitation and interpretation. Preference tests and the application of economic demand theory to welfare assessment are examples of improved behavioral methodology, but much more research is needed on dogs and other species so that animal care and use guidelines can be based on objective data rather than on controversial opinions.