[Morphological changes in chickens receiving cadmium with the feed]. / Morfologichni promeni pri pileta, poluchavali kadmii s khranata.

An experiment was carried out with a total of 100 broiler chickens of the Plymouth Rock breed. From hatching up to the 56th day of age they were offered a maize-soybean ration that was balanced in terms of nutrients and exogenically supplemented with cadmium at various rates in the form of cadmium chloride. The birds were divided into five experimental groups. The first group was given the basic ration with 2.5 mg Cd per kg of feed. The second group was given the same ration with 5 mg Cd; the third group--the same feed with 10 mg Cd; and the fourth group--the same ration with 20 mg Cd. The morphologic studies revealed that the presence of Cd in the feed led to severe dystrophic and necrotic changes accompanied with hemorrhages in the kidneys, heart muscle, and liver. Besides, the birds of the second and third group showed thinning and prolongation of villi intestinales, and those of the fourth group--shortening and thickening of the villi in the small intestine. These changes were indicative of chronic toxic lesions.

[Effect of Bulgarian potassium-calcium zeolites on the assimilation of macro- and trace elements in lambs]. / Vliianie na bulgarskite kalievo-kaltsievi zeoliti vurkhu usvoiavaneto na niakoi makro- i mikroelementi pri agneta.

Experiments were carried out with 12 test and 6 control male lambs from weaning at 20 days of age up to the 65th day. Both groups were kept under equal conditions. The test lambs were given their basic ration plus 4 per cent of a Bulgarian potassium-calcium zeolite. It was found that the treatment of lambs with a zeolite did not lead to changes in the dry matter content, the fats, and the crude protein in the analyzed fractions: carcass head, viscera, and digestive apparatus. There was, however, an increase in the ash. It was also established that the test lambs deposited higher amounts of Ca, P, Mg, and Zn in the parts referred to. The addition of 4 percent zeolite resulted in the increase of the average daily gain by 19.3 per cent.

[Activity of various phosphatases, leucine aminopeptidase and resorption of L-35S-methionine in the jejunum of birds maintained on diets with different levels of magnesium]. / Aktivnost na niakoi fosfatazi, leitsinaminopeptidazata i rezorbtsiiata na L-35S-metionin v ieiunuma na pileta, khraneni s dazhbi s razlichni niva na magnezii.

An experiment was carried out with male broiler chicks from hatching up to the age of 56 days, the composition of the ration used being tabulated. The birds were divided into 4 groups: I--controls that were not given Mg; the basic ration for the birds of the second, third, and fourth group was supplied with 100, 300, and 500 mg Mg per kg of feed, respectively, regardless of the fact that it itself a priori contained Mg at the rate of 1100 mg/kg feed. The activity of p-nitrophenylphosphatase, Mg (Na + K), ATP-ase, 5'nucleotidase, and ;eleucine aminopeptidase as well as the resorption--od L35S-methionine were determined. It was found that the addition of 100 mg/kg Mg to the ration containing 1100 mg/kg Mg led to the considerable increase (P less than 0.01) in the activity of p-nitrophenylphosphatase, Mg, (Na + K), ATP-ase, and 5'nucleotidase in the intestinal mucosa. With the higher rates of magnesium with the addition of 300 and 500 mg/kg to the basic ration the activity of the enzymes cited dropped almost to the level which they had in the control group. The activity of leucine aminopeptidase did not show essential changes at the various levels of magnesium. Neither was the level of magnesium itself of any substantial importance for the resorption of methionine in the small intestine of birds.

[Metablism of DL-selenomethionine in growing chicks]. / Obmiana na DL-selenomethionine v organizma na rastiashti pileta.

The experiments made use of growing male birds. They were given orally 4 muCi of 75Se per kg liveweight each under the form of DL-selenium-methionine, and were bled (via the wing vein) at fixed intervals. Studied was the radioactivity in the liver, kidneys, spleen, pancreas, brain, testes, femoral muscles, and breast bone. The amount of 75Se excreted through the feces and urine was examined at the 24th, 48th, and 72nd hour following the introduction of selenium-methionine. It was found that the resorption of 75Se-selenium-methionine through the digestive tract of birds as registered by the radioactivity of the blood was most intensive between the 3rd and the 6th hour, after which a decline was observed. Most intensive was the metabolism of selenium-methionine in the kidneys, spleen, testes, and pancreas, Comparatively lower is the metabolism of this agent in the breast bone and in the brain. Radioactivity of selenium-methionine was lowest in the femoral muscle. No substantial differences were established in its metabolism in the various organs and tissues studied at the 6th, 24th, 48th, and 72nd hour. As musch as 18.19 per cent of the introduced amount of selenium-methionine was excreted for 72 hours through the feces and urine.