BIOPATHOLOGY OF THE EXPERIMENTAL CRONIC LACK OF ZINC IN SHEEP

Abstract

Biopathology of experimental lack of zinc in Manchega sheep has been studied, comparing a group which received a semisynthetic diet with a content of zinc of 20 ppm,., and a control group, with the same diet but with 60 ppm of zinc. In a haematologic study it is observed a diminishing of the flowing erythrocytes in the lacking animals, 8.270.000 +- 71.100/mm³, with regard to the control ones, 9.225.000 +- 66.120/mm³ . No variation in the number of leukocytes. concentration of haemoglobin and value of the haematocryte was found. Leukocytary formula of the lacking animals showed a lymphocytopeny. 32'5 +- 0'9% whereas the control ones showed 48'11 +- 1'7%, remarkable neutrophily 54'5 +- 1'03% versus 41'9 +- 1'6%, and a slight eosinophily and an increase of monocytes. Glycemia in the lacking animals decreases considerably, 34'6 +- 0'33 mg/100 ml. with respect to the control ones 50'6 +- 0'49 mg/100 ml. Lipohaemia in the lacking animals increases as well as bilirubins total and direct. Serous proteins do not suffer any variations between both groups and only the albumin fraction decreases sligthly in the lacking animals. Activity of GOT enzyme in the serum rises in the lacking animals, 71'6 +- 1'32 U/L in contrast to control ones, 44'9 +- 0'72 U/L.. whereas alkaline phosphatase decreases in the lacking animals, 37'1 +- 0'75 U.KA, with regard to control ones, 45'4 +- 0'8 U. LA.Cholinesterase, minerals Ca. P, Mg. and ions Na⁺ and K⁺ do not present any variations between the both groups of animals. Concentration of zinc in the un proteinized serum is lower in the lacking animals. 1'5 +- 0'02 ppm. than in the control ones, 1'9 +- 0'03 ppm. Equally, in the serum which has not been unproteinized. contents in zinc decreases from 0'65 +- 0'01 ppm. to 0'8 +- 0'01 ppm.. in lacking and control animals respectively.