The review of literature referring to cultivating methods of some parasitic nematodes in vitro is presented (Ascaridia galli, Ascaris suum, Nippostrongylus brasiliensis, Strongyloides fülleborni). It refers general problems and initiate in subject of parasites cultivating in vitro. This work comprises terminology and elementary problems connected with the starting of culture of parasites in vitro, such as: obtaining of parasites to the starting of cultures, the types of cultures in vitro and forming of conditions to determine successful of culture of parasitic nematodes in vitro (sterilization, the selecting of medium, the forming of most favourable physical-chemical conditions).
The authors' observations have confirmed the opinion of Selye (1950) and other authors as regards changes in the C vitamin level of parenchymatous organs in the stress condition. Corroborated are also the quantitative, qualitative, histochemical findings of Tarczyński (1962) on the subject of parasitogenic stress.
The guinea pigs were administrated vit. A (400 i.u.), vit. B₂ (1 mg) or vit. B₁₅ (5 mg). On the 9-th day of the experiment part of them was infectpd with 5000 invasive eggs of Ascaris suum. The invasion lasted 6 days and was controlled by lungs and kidney weight, and number of larvae in the lungs. The activity of amylase was determined by saccharogenic method in both organs. In the lungs of infected animals the activity of alpha-amylase was abouth 3 times lower than in the control. The infection of guinea pigs which were given vitamins did not cause change of enzyme's activity. In the kidney directive tendency was the same, but the differences were smaller. The infection resulted in an increase of relative mass of lungs. This index and number of larvae was considerable smaller in guinea pigs with vitamins A and B₁₅ administration. Any testing agent did not cause change of relative weight of kidney.
The studies were carried out on 40 guinea pig males weighting about 230 g. The experimental animals were infected with 7000 invasive eggs of Ascaris suum. On the 3-rd, 7-th and 10-th day after infection the activity of alpha-amylase was estimated according to Caraway's method in serum, liver, pancreas, lungs, kidneys and spleen. The infection of guinea pigs results in increased activity of enzyme in serum and spleen, and decreased in pancreas, liver, kidneys and lungs. On the 3-rd day after infection the changes in amylase activity were the most intense.
The studies were carried out on the chickens given the diet containing 19% and 11% of protein. On the 7th day of their life one part of the chickens were infected with different doses (125-500) of invasive eggs of Ascaridia galli. The other part of the birds were infected with 500 eggs of A. galli and the invasion lasted from 5 to 49 days. In the extracts from pancreas the activities of trypsin and α-amylase were measured. No differences were observed between trypsin activity of control and infected chickens fed with diet containing 11% of protein. The activity of trypsin was lower in infected chickens fed with diet containing 19% of protein, when the invasion lasted over 15 days. The activity of α-amylase in both groups decreased after infection with more than 100 invasive eggs of A. galli. The intensity and the extensity of invasion were lower in the chickens given the diet of 19% of protein.
The assays were performed on 40 piglets divided into 10 equal groups. Half of the group received food with exogenous HCl. The rest of the animals served as a control. Piglets were gross anatomically examined at the age of 28, 35, 49 and 56 days of life. The content of vitamin C was determined by the method of Roe et al., (Glick, 4) and riboflavin by the method of Bessey et al. (2). Age and addition of HC1 into food did not affect the level of vitamin C in the liver of piglets. However, the content of riboflavin in the livers of piglets receiving HCl at the age of 49 and 52 days was higher comparing to control animals.
The studies were carried out on guinea pig males weighting about 280 g. The animals were infected with 5000 or 20000 invasive eggs of Ascaris suum. On the 3-rd, 7-th, 10-th and 14-th day of invasion the animals were dissected. Lungs were weighted, and the number of Ascaris larvaes was estimated using Baermann method. The activity of alpha-amylase (Fennel's method) and trypsin (Anson's method) were examined in pancreas homogenate. The infection of guinea pigs with A. suum larvaes resulted in a decrease of amylase and trypsin activity in parcreas. The activities were the lowest at the 3-rd day of invasion for amylase and at the 7-th day for trypsin. The results obtained for the animals infected 5 or 20000 invasie eggs A. suum did not differ statically.
Hybrid chickens Astra S fed vitamin A deficiency diet containing 11 or 19% protein were infected with 500 invasive eggs of Ascaridia galli. One part of them received vitamin A in a dose corresponding to daily requirement, other part in double dose. After 7 weeks the extensity and intensity of ascaridiosis were determined. In pancreas and intestinal contents the activities of alpha-amylase, lipase and trypsin were measured. The invasion index was the highest in the group of chickens fed the protein and vitamin A deficiency diet. Vitamin A in a requirement dose lowered the parasite index. The results with double dose of vitamin A were worse in comparison with single dose. The activities of digestive enzymes were lower in infected animals than in the control groups. Vitamin A acted as moderator of the enzymatic changes during ascaridiosis.
Influence of such factors as temperature, pH, CO₂ level and oxidationreduktion potential value in the alimentary tract of host on the stimulation of invasive eggs was studied. Changes of these factors lead to change in permeability of inner layer of egg-shell. Then the hatching fluid is released and its enzymes digest the egg-shell. In the nematodes, which have the free-living larvae, the initiation process can depend on parasite or environmental agents.
The vitamin C content is assessed by colorimetric and titration methods. The results obtained are compared with those of Holz (1961) who - in authors' opinion - failed to determine properly the vitamin, C level in the body of the examined parasites. Moreover, the vitamin C content in the tissues of parasites was found to be independent from the site of its localization in the host organism. The authors believe that the disturbances in the vitamin C balance are due more to defense and adaptation mechanisms of the host than to the more effect of parasitic exploitation.