Assessment of cabergoline as a reproductive inhibitor in coyotes (\u3ci\u3eCanis latrans\u3c/i\u3e)

The efficacy of three oral formulations (gelatin capsule, tablet, oil base) and five dosages (50, 100, 250, 500, 1000 μg) of cabergoline to disrupt reproduction in coyotes (Canis latrans) was evaluated. The type of formulation used had no effect on plasma progesterone and prolactin concentrations or on mean litter size. No adverse side effects (for example, vomiting, anorexia, diarrhea) were observed despite the use of doses of up to 20 times the therapeutic dose used for domestic dogs and cats. All coyotes treated with 50, 100, 250 and 500 μg cabergoline whelped, but plasma progesterone concentrations in these coyotes were lower (P ≤ 0.07) than in control animals at day 7 after treatment. Ten of 11 females treated with 1000 yg cabergoline whelped, but progesterone concentrations in these coyotes were lower than in control animals up to day 14 after treatment ( P ≤ 0.04). Dosages of 1 000 μg cabergoline decreased blood serum prolactin (P ≤ 0.1 0) and progesterone (P ≤ 0.06) concentrations, but apparently failed to decrease progesterone below the threshold necessary to maintain pregnancy in all but one animal. However, progressive inhibition of prolactin and progesterone with increasing doses of cabergoline indicated that higher dosages might be effective in coyotes. Survival of pups born to cabergoline-treated females was not different (P \u3c 0.001) from that of pups born to control females, but mean litter size was smaller for females treated with cabergoline (P ≤ 0.073) than for the control females. Although all cabergoline treatments in this study were ineffective at preventing reproduction in coyotes, progressive inhibition of prolactin and progesterone with increasing dosages of cabergoline indicates that higher doses might be effective in preventing reproduction in coyotes. However, the physiological differences from other canine species in dopamine D2 receptors and mechanisms of luteal support may ultimately prevent the use of cabergoline for reproductive control in coyotes

EquiFACS: the Equine Facial Action Coding System

Although previous studies of horses have investigated their facial expressions in specific contexts, e.g. pain, until now there has been no methodology available that documents all the possible facial movements of the horse and provides a way to record all potential facial configurations. This is essential for an objective description of horse facial expressions across a range of contexts that reflect different emotional states. Facial Action Coding Systems (FACS) provide a systematic methodology of identifying and coding facial expressions on the basis of underlying facial musculature and muscle movement. FACS are anatomically based and document all possible facial movements rather than a configuration of movements associated with a particular situation. Consequently, FACS can be applied as a tool for a wide range of research questions. We developed FACS for the domestic horse (Equus caballus) through anatomical investigation of the underlying musculature and subsequent analysis of naturally occurring behaviour captured on high quality video. Discrete facial movements were identified and described in terms of the underlying muscle contractions, in correspondence with previous FACS systems. The reliability of others to be able to learn this system (EquiFACS) and consistently code behavioural sequences was high—and this included people with no previous experience of horses. A wide range of facial movements were identified, including many that are also seen in primates and other domestic animals (dogs and cats). EquiFACS provides a method that can now be used to document the facial movements associated with different social contexts and thus to address questions relevant to understanding social cognition and comparative psychology, as well as informing current veterinary and animal welfare practices