Domosedan

In all but one captive bull procedures were carried out under standing sedation with medetomidine and butorphanol, as previously described [21 (link)]. One captive and all four wild bulls were fully immobilized using a combination of 12–15 mg etorphine (M99, Novartis Animal Health, Isando, South Africa) and 10–20 mg detomidine (Domosedan, Zoetis Animal Health, South Africa), South Africa) according to estimated weight and delivered remotely from a dart gun fired from a helicopter (wild bulls) or the ground (captive bull). Reversals were achieved with 100–150 mg diprenorphine (M5050, Novartis Animal Health, Isando, South Africa) and atipamezole HCL (Antisedan, Zoetis Animal Health, South Africa) administered intravenously.

Thoroughbred weanlings were included as part of the annual screening programme on three farms. A clinical examination of each weanling demonstrated normal gait at walk and normal cardiac auscultation. Light sedation using intravenous administration of 3.5 mg of Detomidine (Domosedan, Zoetis) 3.5 mg of Butorphanol (Torbugesic, Zoetis) and 3.75–5 mg of Acepromazine (Calmivet, Vetoquinol).
The ultrasonographic examinations were performed by an ECVDI/ACVR (EDI) board certified veterinary radiologist. The hair and skin of each joint was thoroughly soaked with warmed alcohol. A portable ultrasound machine (GE Logiq R7) and a 5–13 MHz Linear Transducer (GE 12 L-RS) was used with focal zone(s), frequency, time gain compensation (TGC) and overall gain optimised by the ultrasonographer. The transducer was held with the marker located medially in a transverse orientation or proximally in the longitudinal plane. Representative cineloop images were recorded and saved for each weanling, facilitating subsequent review.