Today's questions are contributed by Eric Hutchinson DVM, Dipl. ACLAM who is an expert in animal behavior. Thanks Eric!
In laboratory settings we do a lot to ensure the psychological well-being of our animals, from giving them social partners to providing environmental enrichments like foraging opportunities. From conducting positive reinforcement training to making sure our routine husbandry is minimally stressful. Despite this, some animals will still develop signs of psychological distress such as abnormal behaviors. In these cases, veterinarians are often called upon to serve as psychiatrists to the animals, blending behavioral techniques and drug therapies to address the environmental and biological causes of this distress. Below are a few real-life examples of animals who may be in psychological distress. How would you handle them?
1) A nonhuman primate has been observed biting itself in the past, but has never caused any wounds. It has been treated for several months with twice daily diazepam (valium), with no convincing improvement. Recently, diazepam treatment was discontinued and treatment with fluoxetine (Prozac) was begun. Within a few days of this change, there was a noticeable increase in the amount of self-biting, and even some mild wounds found for the first time. What are some possible causes for the increase in biting and wounds? Can we determine from this whether the fluoxetine is likely to be effective?
2) An investigator calls to report that her transgenic mice have been showing a curious pattern of progressive hair loss. After the phone call, you suspect a possible infectious etiology, such as C. bovis. When you examine the animals, you see that several of them have hair loss similar to the picture at right. What is the likely etiology of this hair loss? Is this similar to any human disorders? Are there any effective treatments?
3) An otherwise friendly dog has been reported to be increasingly stressed around the time of cage cleaning each day. It started with lots of barking and whining, but has recently turned into cowering at the back of the cage. Yesterday during cleaning, the dog was cowering and then suddenly lunged at the caretaker, who barely avoided being bitten. What are some potential treatments in this case? Are there any drug therapies that might be contraindicated? Would your drug choices differ if this was a macaque who was reported to “lose it” once a week during cage change?
4) You are called to examine a 7 y/o male rhesus macaque who arrived in your facility at the age of 5 with frustratingly little detail in its medical record up to that point. Multiple attempts have been made to socially house this animal but it has led to fighting each time because it doesn’t seem to respond to social cues normally. You find the animal awake and alert, but curled into a ball and rocking while sucking its thumb. On closer inspection, you find lesions on the arms and legs that look like the picture at left. From this information, can you determine a likely part of this animal’s history prior to arriving in your facility? Can you guess at any specific neurochemical abnormalities based on your observations? What treatments might you consider in this case? Once you begin treatment, how will you determine whether it is working?
