Abstract
The effect of low temperature exposure on the motility of Diphyl-lobothrium latum plerocercoids was studied, with the particular aim of finding the exposure that immobilizes all the larvae in fish freezing. Both isolated larvae immersed in normal horse serum and larvae enclosed in pieces of muscle tissue of the size of 1 cm3 were tested. The pieces of tissue containing a larva were placed in the middle of a plastic beaker filled with densely packed minced fish flesh. In the central part of this phantom, where the plerocercoids were situated, the temperature decline was considered to take place in the same way as in the interior of a whole fish. A total of 200 isolated larvae were tested, and a temperature of −14° G was found to have a fully immobilizing effect on them. The number of plerocercoids frozen enclosed in muscular tissue was 453, and −10° G was found to immobilize them. The observed difference seems to be mainly due to the cryoprotective properties of serum.
Sammanfattning
Den effekt, som låga temperaturer har på motilitet av Diphyllobothrium latums plerocercoider, undersöktes speciellt med målet att finna den kylbehandling, som immobiliserar alla larver vid nedfrysning av fisk. Både isolerade larver nedsänkta i normalt hästserum samt larver inneslutna i fiskmuskelbitar av 1 cm3 storlek blev testade. Vävnadsbitarna, innehållande en larv, placerades i mitten av en plastbägare fylld med tätt packat finmalet fiskkött. I den centrala delen av denna fantom, där plerocercoiderna var belägna, ansågs temperatursänkningen försiggå på samma sätt, som i de inre delarna av en hel fisk. Inalles 200 isolerade larver undersöktes, och man fann, att temperaturen —14° C immobiliserade dem alla. Antalet plerocercoider nedfrysta i fiskmuskelbitar var 453, och man kunde konstatera, att —10° C hade immobiliserande verkan på dem alla. Den observerade skillnaden beror sannolikt på serumets köldskyddande verkan.
Full Text
The Full Text of this article is available as a PDF (1.2 MB).
References
- 1.Doebbler G F. Gryoprotective compounds. Cryobiology. 1966;3:2–11. doi: 10.1016/S0011-2240(66)80144-X. [DOI] [PubMed] [Google Scholar]
- 2.Kajava Y. Några iakttagelser rörande den breda bandmaskens (Bothriocephalus latus) blåsmask. (Observations on the larvae of the broad tapeworm (Bothriocephalus latus)) Finska Läk-Sällsk. Handl. 1913;55:700–707. [Google Scholar]
- 3.Lovelock J E. The mechanism of the protective action of glycerol against haemolysis by freezing and thawing. Biochim. biophys. Acta (Amst.) 1963;11:28–36. doi: 10.1016/0006-3002(53)90005-5. [DOI] [PubMed] [Google Scholar]
- 4.Nash T. The chemical constitution of compounds which protect erythrocytes against freezing damage. J. gen. Physiol. 1962;46:167–175. doi: 10.1085/jgp.46.1.167. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Pesonen T, Wikgren B-J. Bandmasklarvernas salt- och temperaturtolerans. (The salt and temperature tolerance of the fish tapeworm larvae) Mem. Soc. Fauna Flora Fenn. 1959;35:112–118. [Google Scholar]
- 6.Polge C A, Smith U, Parkes A S. Revival of spermatozoaafter vitrification and dehydration at low temperatures. Nature (Lond.) 1949;164:666. doi: 10.1038/164666a0. [DOI] [PubMed] [Google Scholar]
- 7.Reuter J. Studies on plerocercoids of Diphyllobothrium dendriticum. I. The dry weight/fresh weight ratio of the tissues under various physiological conditions. Acta Acad. Åboensis, Ser. B. 1967;27:1–15. [Google Scholar]
- 8.Salminen K. The effect of household freezing on the infestiveness of Diphyllobothrium latum from fish to man. Nord. Vet.-Med. 1968;20:543–556. doi: 10.1186/BF03547983. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Vos O, Kaalen M C A C. Prevention of freezing damage to proliferating cells in the tissue culture. A quantitative study of a number of agents. Cryobiology. 1965;1:249–260. doi: 10.1016/0011-2240(65)90031-3. [DOI] [PubMed] [Google Scholar]
- 10.Wardle R A. Significant factors in the plerocercoid environment of Diphyllobothrium latum (Linn.) J. Helminth. 1933;11:25–44. doi: 10.1017/S0022149X00030467. [DOI] [Google Scholar]
- 11.Wikgren B-J, Nikander P. Cause of death of plerocercoids of Diphyllobothrium latum (L.) at low temperatures. Mem. Soc. Fauna Flora Fenn. 1964;40:189–192. [Google Scholar]