Medycyna Wet. 66 (2), 127-130, 2010

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Skrzypek G., Nowakowski Z.
Intensity of Trichinella spiralis invasion in the muscles of experimentally infected rabbits
Research concerning the distribution as well as intensity of Trichinella larvae in the bodies of hosts is crucial from the perspective of the invasionology and diagnostics of Trichinellosis. Diagnosing Trichinella spiralis is dependent on the following factors: intensity of Trichinella spiralis invasion in the muscles, the weight of the material, the specific types of muscles, animal species, as well as the method of testing for Trichinellosis presence. The goal of the authors’ study was determining the distribution and intensity of Trichinella spiralis larvae invasion in selected rabbit muscles experimentally infected with a small dose of Trichinella. The investigations were conducted on 8 healthy slaughter rabbits that weighed 5 kg. The rabbits were infected with a single dose of 90 Trichinella spiralis muscle invasive larvae derived from a boar. The rabbits were slaughtered 60 days after infection. Select entire muscles from the left and right sides of the carcasses were chosen for investigation. From rabbit the following muscles were tested for Trichinellosis presence: Diaphragma (part: lumbalis, costalis, sternalis), m. masseter, antebrachii, tongue, m. biceps brachii, pterygoideus, cruris, mm. intercostales, m. semitendinosus and semimembranosus, as well as m. longissimus lumborum. The distribution as well as intensity of the T. spiralis larvae invasion (trichinellosis count per 1 g of muscle, as well as percentage in relation to the diaphragm = 100% ) in the investigated muscles was determined by the digested method according to Commission Directive (WE) no. 2075 as of December 5, 2005. All the rabbits used in the experiment were infected: encysted T. spiralis larvae were confirmed in all the examined muscles. The results of the conducted investigations showed statistically significant differences in the T. spiralis invasion of specific muscles. The greatest trichinellosis larvae invasion occurred in the m. masseter, antebrachii and in the diaphragm. The intensity of the T. spiralis invasion in the examined muscles was 18.92 to 1.20 per 1 g of muscle and was from 1.08 to 17.13 times less than the trichinellosis invasion in the m. masseter. These results indicate the high suitability of the m. masseter for investigating the presence of trichinellosis in rabbits. Rabbits are susceptible to T. spiralis infection. The trichinellosis larvae undergo encystment in their muscles. The muscle tissue of all rabbits infected with T. spiralis was brought on by rat trichinellosis.
Key words: T. spiralis, rabbits, experimental infection