Postnatal anemia and thrombocytosis in suckling rabbits: influence of delayed weaning and iron supplies.
Two groups of suckling rabbits were studied from the 15th to the 40th day after birth, one group receiving mothers milk only, the other having the choice of iron-containing food pellets from the 20th day. In the milk-only group, the plasma iron concentration (P-Fe), blood hemoglobin concentration (B-Hb), red blood cell count (B-RBC), and mean corpuscular volume (MCV) declined continuously, whereas the hemoglobin mass of the blood (Hb-mass) remained unchanged, and the blood platelet count (B-PLTS), plasma platelet count (P-PLTS), and the estimated platelet release to the blood (PLT-release) showed a continuous rise. The milk-pellet group showed the same pattern until the 25th-30th day; thereafter, P-Fe, B-Hb, and Hb-mass rose markedly, whereas B-PLTS and PLT-release declined. At the time of weaning, both groups showed bimodal erythrocyte volume distribution curves. Thereafter, the milk-only group developed a pure microcytemia, whereas the milk-pellet group got normovolemic erythrocytes only. In conclusion, the erythropoiesis in suckling rabbits is characterized by a balanced recycling of an essentially constant amount of available iron, preventing rise of Hb-mass. The anemia thus reflects a failure of the Hb-mass to keep up with the growth-related rise in plasma volume. A close relationship exists between postnatal iron deficient microcytic anemia and thrombocytosis.
Holter
P H
PH
Laboratory for Clinical Physiology, Ullevaal Hospital, Oslo, Norway.
Refsum
H E
HE
D000751:Anemia, Neonatal / Q000209:etiology*; D000818:Animals; D000833:Animals, Suckling / Q000097:blood*; D004032:Diet; D004906:Erythrocyte Count; D004911:Erythrocyte Volume; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D007501:Iron / Q000097:blood; D000090463:Iron Deficiencies; D010976:Platelet Count; D011817:Rabbits; D013922:Thrombocytosis / Q000209:etiology*; D013997:Time Factors; D014886:Weaning
D006454:Hemoglobins; D007501:Iron