Fatigue of three skeletal muscles in domestic and wild pigs

Abstract

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.

Investigations on the radiocaesium contamination of wild boar (Sus scrofa) meat in Rhineland-Palatinate: a stomach content analysis

“…On the basis of these figures, daily intake of 1,000 Bq will produce meat contamination of only 170-330 Bq/kg. But for wild boars there is some evidence that twofold to threefold higher T ag values have to be assumed: other studies have shown that lower average body weight at harvest (Nalezinski et al 1996) and higher proportion of oxidative muscle fibres (Szentkuti and Sallai 1988) probably leads to an increased netto radiocaesiumretention ability in wild boars compared to domesticated conspecifics. The same effect might result from a low potassium content in the natural forage: we determined the potassium content from ten randomly collected stomach contents from summer 2002 filled with natural forage (no bait maize) by measuring the K-40-concentration with a HPGe detector.…”

Consequences of Selection on Muscle Composition. A Comparative Study on Gracilis Muscle in Wild and Domestic Pigs

“…Genetic improvement led to a remarkable change of fattening traits including carcass composition. This improvement is particularly apparent in lean-meat percentage at the expense of adipose tissue (McCampbell et al, 1974;Bader, 1983;Szentkuti and Sallai, 1988) and may be attributed to about threefold higher concentrations of growth hormone (GH) in domestic pigs as opposed to wild pigs (Claus et al, 1990). Under physiological conditions, such an increase in muscle weight is assumed to result mainly from hypertrophy of muscle fibres and less so from an increase in the number of fibres (hyperplasia; Ashmore et al, 1972;Swatland, 1978;Dayton and Hathaway, 1989).…”