Changes in lymphoid organs and blood lymphocytes induced by vitamin A deficiency and Newcastle disease virus infection in chickens.

The effect of vitamin A deficiency in the presence or absence of Newcastle disease virus infection (NDV, La Sota strain) on weight of lymphoid organs and on the number and type of circulating white blood cells (WBC) was investigated in chickens. Day-old chickens with limited vitamin A reserves were fed purified diets containing either marginal (ad libitum) or adequate (pair-fed) levels of vitamin A and at 21-28 days of age; half the chickens in each group were infected with NDV. Vitamin A deficiency resulted only in significantly lower absolute and relative weights of bursa of Fabricius and after infection both weights of bursa and thymus were significantly lower. Relative weight of spleen was significantly higher after infection irrespective of vitamin A status. Liver weights were not affected by vitamin A status and/or NDV infection. Both vitamin A deficiency and NDV infection resulted in lymphopenia, while the lowest number of WBC were observed in vitamin A-deficient chickens during the acute phase of NDV (5 days after infection). Subsequent to lymphopenia due to NDV infection, a marked lymphocytosis was observed in controls and to a lesser extent in vitamin A-deficient birds. These results indicate that vitamin A deficiency, which is aggravated by concomitant NDV infection, affects lymphoid cell systems.

Nutritional status: haematology and albumin. Euronut SENECA investigators.

In the context of the Euronut SENECA study of nutrition and the elderly, performed in 19 towns situated in 12 European countries, blood haemoglobin and haematocrit, and serum albumin were measured in a large sample of 70-75-year-old subjects. The mean haemoglobin (Hb) values for the different towns ranged from 144 g l-1 to 157 g l-1 for men and from 131 g l-1 to 150 g l-1 for women. The town haematocrit (Hct) means ranged from 43.0% to 48.9% for men and from 39.7% to 46.4% for women. No clear geographical pattern emerged for either Hb or Hct. The 95% ranges (2.5-97.5 percentile intervals) for Hb and Hct for all towns combined (without any claim of being representative of Europe) were very similar to those reported in the NHANES II study of the USA. Prevalences of anaemia, using the WHO definition (Hb less than 130 g l-1 for men and Hb less than 120 g l-1 for women) were 5.2% for men and 5.7% for women. The town mean serum albumins ranged from 40.3 g l-1 to 44.3 g l-1 for men and from 40.3 g l-1 to 43.2 g l-1 for women. No clear geographical pattern emerged. Mean values were somewhat lower than for younger adults and comparable to other published data. Most albumin values were in the normal range, with only 2.0% of both men and women having levels below 35 g l-1 and only 0.4% of men and no women having levels below 30 g l-1. These results show that these 70-75-year-old subjects who chose to participate in the study were in relatively good health as judged from their haemoglobin, haematocrit and serum albumin levels.

Objective clinical examination of poultry as illustrated by the comparison of chickens with different vitamin A status.

One day old pullets derived from marginally vitamin A deficient laying hens were fed diets containing either adequate or marginal amounts of vitamin A. At the age of 34 days, animals fed the diet low in vitamin A had group mean plasma concentrations of retinol which were one tenth the mean plasma concentrations of controls. When compared with their controls, the deficient animals displayed body weights which were on average 16% less. Of 20 pullets per dietary group one control animal and 9 deficient animals died by the age of 34 days. At the age of 29 days, control (n = 16) and deficient chickens (n = 11) were examined clinically by assigning scores to a number of parameters. Three assessors carried out the examination independently. The birds were presented for examination at random and their treatment groups were not disclosed to the assessors. Out of 26 parameters assessed quantitatively per individual animal, only three parameters discriminated between control and deficient chickens. Deficient animals grew poorly, had a hunched up posture and increased fluid content in faeces. Classical signs of chronic vitamin A deficiency in domestic fowl such as bone deformities, keratinization of the tongue and decreased transparency of the cornea were not observed.

[Harmful elements versus iron, zinc and copper: their interactions in animals and humans. I. Mercury, tin, nickel, selenium, fluorine and aluminum]. / Pier wiastki szkodliwe a zelazo, czynk i miedz: interakcje w organizmie zwierzat i ludzi. Cz. I. Rtec, cyna, nikiel, selen, fluor, glin.

A literature survey was made of the interactions--in the organism--between some food contaminating elements (mercury, tin, nickel, selenium, fluorine, aluminium) and iron, zinc and copper. The harmful elements may disturb the mineral metabolism already at the stage of intestinal absorption. Moreover, they bring about changes in microelement distribution in the tissues and cells. On account of their approximately similar chemical structure, they compete for the sites of binding to some proteins, including enzymic ones. In this respect a special role is played by ++metallothionein, a protein with the ability of regulating free metal contents in the tissues and thus possibly displaying some detoxifying properties. Many mechanisms and relationships determining the interactions between the surveyed food contaminants and iron, zinc and copper remain, however, not elucidated.