Propoflo plus

Muscle biopsy was performed at 3-monthly intervals from 3 to 18 months of age. Muscle samples (∼0.5 cm³) were collected by open biopsy from the left vastus lateralis muscle, with dogs under general anaesthesia. Dogs were premedicated with intravenous methadone (0.2 mg/kg, Comfortan, Dechra) 30 min prior to induction of anaesthesia with intravenous propofol (1-4 mg/kg, PropoFlo Plus, Zoetis) to effect and maintained with sevoflurane (1.5-3.5%, SevoFlo, Zoetis) in oxygen administered via a Datex-Ohmeda Aestiva/5 anaesthesia machine. All dogs received intravenous carprofen (2 mg/kg, Rimadyl, Pfizer) for pain relief and cefuroxime antibiotic (20 mg/kg, Zinacef, GSK). A small piece of muscle tissue was trimmed from each sample, placed in a cryovial and snap frozen in liquid nitrogen, and the remaining tissue was mounted on corks in transverse orientation using cryoMbed (Bright Instruments) and frozen in liquid nitrogen-cooled isopentane. Once frozen, all samples were stored at −80°C until use.

Dogs underwent general anaesthesia consisting of pre-medication with intravenous methadone (0.2 mg/kg, Comfortan, Dechra) prior to induction of anaesthesia with intravenous propofol (1-4 mg/kg, PropoFlo Plus, Zoetis), and maintenance with inhaled sevoflurane (1.5-3.5%, SevoFlo, Zoetis) in oxygen administered via a Datex-Ohmeda Aestiva/5 anaesthesia machine. To reduce the need for separate general anaesthetic regimens, this work was conducted alongside vastus lateralis muscle biopsy collection (results of which are reported elsewhere; Hildyard et al., 2022 (link)): biopsy samples were collected from the left pelvic limb prior to the muscle physiology protocol (conducted on the right pelvic limb). All dogs received perioperative intravenous cefuroxime antibiotic (20 mg/kg, Zinacef, GSK). For pain relief, a single intravenous dose of carprofen (2 mg/kg, Rimadyl, Pfizer) was given perioperatively, followed by postoperative oral carprofen once daily for 3 days (2 mg/kg, Rimadyl, Pfizer). Body temperature was maintained at approximately 37°C, by the use of an electric heat-pad and a warming blanket (Bair Hugger, Patient Warmer 505).