The semitendinosus, the gastrocnemius and the soleus muscle were stimulated in situ in young, female domestic pigs (Sus scrofa domestica, German Landrace) and in European wild pigs (Sus scrofa scrofa), by supramaximal impulses via the sciatic nerve. Fatigue indices of the whole muscles were registered during a continuous supramaximal stimulation with square wave impulses (0.3 ms) that were given for 10 s with a frequency of 100 Hz. In domestic pigs, fatigue indices of all three muscles were significantly (p less than 0.001) lower than in wild pigs. The extremely rapid fatigue of domestic pig muscles was remarkably different from that measured in wild pigs, comparing either pigs of nearly the same body weight (FI: 22.7/58.6 for the semitendinosus muscle; 28.5/63.7 for the gastrocnemius muscle; 37.7/81.2 for the soleus muscle), or pigs of nearly the same age (FI: 23.1/58.8 for the semitendinosus muscle; 25.9/65.1 for the gastrocnemius muscle; 33.6/81.4 for the soleus muscle). Doses of anaesthetics needed for appropriate general anaesthesia of young wild pigs were two to three times higher than doses used for domestic pigs. Differences in fiber type composition of the muscles, and alterations in signal transmission characteristics at neuromuscular junctions are discussed as to be associated with the extremely low fatigue resistance of the domestic pig muscles.
The gastrocnemius muscle was stimulated in situ in young female domestic pigs (DP, Sus suofa domestica, German Landrace; n = 24) and in European wild pigs (WP, Sus scrofa suofu; n = 20), by short (0.1 ms) square-wave impulses via the sciatic nerve. Evoked compound action potentials were recorded from the sciatic nerve, from the Ramus muscularis distalis of the tibial nerve and from the end plate region of the muscle tissue. Maximum nerve conduction velocities (NCV) were 58.8 f 10.4m/s in DP and 77.7 f 16.5 m/s in WP. Time of neuro-muscular transmission ("distal latency") for evoked compound action potentials from the Ramus gastrocnemius of the tibial nerve into the gastrocnemius muscle was 2.32 f 0.54 ms in DP and only 1.27 f 0.25 ms in WP. Electromechanical coupling time intervals in the gastrocnemius muscle were 11.95 k 2.26 ms in DP and 9.95 k 1.07 ms in WP.Motor end plates were visualized histochemically and classified as of the red, intermediate and white type according to their shape and arborization. High extrajunctional acetylcholinesterase activity was observed in the close vicinity of the junctions of muscles in young DP (3.5 month, 40 kg), which was absent in WP muscles and also in DP muscle at older age.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.