Oxytocin is used increasingly in mares to prolong corpus luteum (CL) function to suppress estrus. When mares develop prolonged CL function in response to oxytocin treatment, the CL generally remains functional for 60–90 days. However, a longer duration of CL function can make this method of estrus suppression even more clinically useful. We hypothesized that human chorionic gonadotropin (hCG) treatment during the period of oxytocin-induced prolonged CL function would extend the duration of CL function (i.e. beyond 90 days). Prolonged CL function was induced in mares (n = 14) by treating them with 60 units of intramuscular oxytocin once daily on days 7–14 after ovulation. Mares were then randomly assigned equally to a control group that received no additional treatment and an hCG-treated group that received 2,500 units of intramuscular hCG on days 30, 45, 60, 75, and 90 after ovulation. Jugular blood samples were collected for progesterone concentration determination on the day of ovulation and then 3 times (M, W, and F) weekly for 120 days. Duration of CL function was not different (p > 0.05) and it was 78.0 ± 7.5 and 91.4 ± 20.4 days (mean ± standard deviation [SD]) in control and hCG-treated mares, respectively. Therefore, hCG treatment (during the period of oxytocin-induced prolonged CL function) did not extend CL function, hence alternative methods should be explored.

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Surgical destabilization of the stifle joint via cranial cruciate ligament desmotomy (CCLD) is a routine procedure for the study of osteoarthritis (OA). Traditionally performed in rats, rabbits, cats, and dogs, CCLD in sheep provides an opportunity to study the pathology and treatment of joint instability in a species whose stifle better represents the equivalent human femorotibial joint. The surgical approaches for CCLD in sheep are variable and can result in inconsistent outcomes. Eight sheep underwent CCLD for use in a gene therapy study. We report this case in which six of the eight sheep were clinically diagnosed by pathognomonic signs and later confirmed by postmortem dissection, with injury of the peroneus tertius (PT) muscle. The PT plays a crucial role in the normal gait of large animals, including sheep. Injury to the PT results in failure of the reciprocal apparatus of the hind limb in which the hock can be extended during stifle flexion creating a varied gait and an indiscriminate increase in instability of the stifle and hock joints. Restricted movement postoperatively may provide decreased variability in surgical outcomes. Alternatively, increased stifle instability via CCLD coupled with PT transection or PT transection alone could potentially provide a superior model of stifle instability and OA development in sheep.

HIGHLIGHTS• Survey data collected from equine-assisted services programs that offer unmounted (ground) programs document the need for standardized equine safety evaluations. • 36.7% of respondents used an objectively defined method (i.e., used a defined percentage, number, rating scale, or yes/no checklist that must be achieved by the equine prior to them entering the program), while 63.3% did not use an objectively defined method. • Common equine safety concerns were biting/nipping, spooking from external stimuli, and stepping on a person's foot. ABSTRACT. The Professional Association of Therapeutic Horsemanship International (PATH Intl.) is an organization that supports equine-assisted services (EAS).As the standard setting organization for EAS programs, PATH Intl. established evaluation metrics to ensure the safety of both humans and equines. One of the standards, Equine Management and Welfare Standard 2 (EQM-2), calls for EAS programs to have an unbiased equine assessment process. This standard can be implemented in different ways depending on program policies. Survey data was collected on each type of center with regard to the implementation of the equine assessment standard in unmounted (ground) activities, as well as self-reported safety and equine evaluation procedures for unmounted (ground) activities. The primary research objective was to identify differences between PATH Intl. Premier Accredited Member Centers and PATH Intl. Member Centers. No significant differences were found between center types except for incidents of human injury (Χ 2 [2] = 9.908; p =.007). Both types of centers had a variety of responses related to the implementation of their evaluation procedures, including, but not limited to, how many individuals evaluate each equine, the type of assessment tool, and the frequency of evaluations. Future studies should examine the different evaluation methods in depth to determine an objective