R. H. Harms

Pathology of the aorta of chicks fed a copper-deficient diet

Abstract Day-old chicks were fed normal and copper-deficient diets for 6 weeks. Approximately 50% of the birds on the deficient diet died of hemorrhages. The principal pathologic alteration found in the syndrome was elastic fiber degeneration of the aorta. According to electron microscopy, elastic fiber degeneration occurred in three steps. Initially, there was swelling of elastic fibrils and increased electron density of involved elastic fibers. Secondly, there was partial dissolution of the matrix portion of elastic fibers so that they had a vacuolated pattern. The last retrograde stage consisted of complete dissolution of the matrix with persistence of naked, twisted, swollen elastic fibrils. Degeneration of elastic fibers originated in the periphery and eventually extended to the central area.

Skeletal and cardiovascular lesions in turkeys induced by feeding beta-aminopropionitrile☆

Abstract Beta-aminopropionitrile toxicosis in turkeys induced skeletal and cardiovascular lesions. Enlarged hocks with widening of the epiphyseal plate and articular cartilage, green tinting of the skin over swollen joints, and synovitis were the skeletal defects that were found. Joint lesions apparently resulted from impediment of endochondral mineralization and maturation of chondrocytes in the epiphyseal plate and articular cartilage. Cardiovascular alterations resulting from BAPN feeding included ground substance increase, swelling and disorganization of collagenous fibers, and elastolysis. These changes cause polypoid intimal thickenings and the induction of dissecting aneurysms. Intimal arteriosclerotic plaques were found in the posterior aorta of “normal” turkey poults. There is a possibility that such lesions are a prerequisite for the development of dissecting aneurysms.

Electron microscopy of the cardiovascular system of the normal and beta-aminopropionitrile fed turkey

Abstract The ultrastructure of the cardiovascular system of the normal and BAPN-fed turkey poult is described. The posterior aorta of normal birds contained smooth muscle cells in the tunica intima; smooth muscle cells bound together by elastin and collagen in the tunica media; and collagen, elastin, spindle-shaped cells, nerves and vasa vasorum in the tunica adventitia. The essential aortic pathology caused by BAPN toxicosis included endothelial cell swelling and proliferation, elastic fiber fragmentation, collagenous fiber swelling and matting, and ground substance increase.

Pathology of aortic atherosclerosis and dissecting aneurysms of turkeys induced by diethylstilbestrol

Abstract A high incidence of aortic ruptures due to dissecting aneurysms occurs in male turkeys following treatment with diethylstilbestrol (DES). About 5% of the birds examined at the termination of the experiment had saccular aneurysms of the posterior aorta. Aortic atherosclerosis was also produced by DES treatment. Smooth muscle cells in the tunica media developed lipidosis. Adjacent smooth muscle cells became widely separated from each other by extracellular lipid, serum, and particles that appeared to be lipoprotein. The accumulation of extracellular material caused weakening of the aortic wall, the development of dissecting aneurysms, and eventual rupture. Most of these ingredients apparently entered the vascular wall through breaks which developed between adjacent endothelial cells and less frequently by way of dilated intercellular boundaries between endothelial cells.

β-Aminopropionitrile-induced aortic ruptures in turkeys: Inhibition by reserpine and enhancement by monoamine oxidase inhibitors

Abstract Reserpine prevented mortality from aortic ruptures when a level of 0.07% BAPN was fed to turkeys. The tensile strength of aortas of poults fed 0.07% BAPN-reserpine was about 2.5 times greater than that of poults fed only BAPN. Larger amounts of lysine were found in isolated elastin from aortas of birds fed 0.07% BAPN than from the aortas of turkeys fed 0.07% BAPN-reserpine. Profound elastic fiber changes were seen in aortas of poults fed 0.07% BAPN; minor changes of aortic elastic fibers and collagenous fiber proliferation were seen in aortas of birds fed 0.07% BAPN-reserpine. Feeding of low levels of BAPN (0.02%) caused a low mortality rate. Addition of a monoamine oxidase (MAO) inhibitor (Nardil) to diets containing such a BAPN level resulted in high death rates, whereas reserpine in combination with these two chemicals resulted in a lower mortality rate. The tensile strengths of aortas from the last group were greater than that of the first group, but lysine content of isolated elastin was less. Little, severe, and moderate elastic fiber alterations were seen in aortas of turkeys fed 0.02% BAPN, 0.02% BAPN-Nardil, and 0.02% BAPN-Nardil-reserpine, respectively. The possible mechanism by which diets containing reserpine reduced the incidence of aortic rhexis induced by BAPN is discussed.

Aortic rupture in turkeys induced by diethylstilbestrol.

Summary Weekly implantation of BroadBreasted Bronze turkeys with 24 mg of DES increased the incidence of aortic ruptures. Poults fed a 16% protein diet developed more aortic ruptures (58%) than turkeys fed a 28% protein diet (29%).

Effect of Dietary Iodine Upon Egg Production, Fertility and Hatchability.

Summary Laying hens were fed 312 to 5000 ppm iodine as KI in a practical laying diet and egg production and hatchability determined. Production ceased within the first week in hens fed the highest level and production was reduced at the lower levels. Fertility of the eggs produced was not affected but early embryonic death, reduced hatch-ability and delayed hatching resulted. Hens resumed egg production within seven days after removal from iodine feeding.

Influence of High Dietary Sodium Chloride on Aortic Ruptures in Turkeys Induced by Diethylstilbestrol.

Summary The incidence of aortic ruptures in turkeys induced by injection of DES in a liquid form was modified by dietary composition including high NaCl levels. Diethylstil-bestrol injections also caused hyperproteinemia, hypercholesterolemia, hyperlipemia and lowered blood pressure. High NaCl diets did not affect blood pressure. The technical assistance of J. W. Carlisle and C. J. Miller is acknowledged.

Blood Changes in Turkeys Associated with a Copper Deficiency.

Summary Day-old turkey poults were fed 5 levels of supplemental copper for 6 weeks. There was a significant stimulation of growth in those fed 1.32 to 3.96 ppm of added copper. Microhematocrits of all turkeys were within normal ranges. The erythrocytes of birds fed 1.32 ppm of supplemental copper had abnormally shaped nuclei, while those of poults fed 1.98 and 3.96 ppm of copper were normal. Nuclear changes consisted of lobulated nuclei, duplication of nuclei, forked nuclei and other bizarre manifestations. Heart and liver cytochrome oxidase activity was greater in those birds fed 1.32 to 3.96 ppm of added copper.

Comparison of Parenterally and Orally Administered Diethylstilbestrol In Production of Aortic Ruptures in Turkeys.

Summary The incidence of aortic ruptures in turkeys was similar when DES was administered either by the oral (16 and 32 g/100 lb of feed) or parenteral (30 mg/week) routes. Comparable hyperlipemia and lowering of blood pressure occurred in both treatment methods.