Effect of maternal dietary zinc on growth and mitogenic responsiveness in suckling mice.
The effects of varied levels of maternal dietary zinc on growth and immunological development of suckling A/J mice were studied. From 5 days postpartum, lactating dams were fed biotin-fortified egg-white diets containing the following levels of zinc: 1.6 microgram/g (low zinc), 3.6 microgram/g (intermediate zinc), 5.8 microgram/g (moderate zinc) and 30 microgram/g (control). At 17 days of age, low zinc pups exhibited reduced body weight gain (70%), smaller thymuses and spleens, and reduced splenocyte numbers (18%). Intermediate zinc pups had normal body weights but slightly reduced spleens and thymuses; moderate zinc pups were unaffected. Since suckling mice are not fully immunocompetent, splenic mitogenic responses to phytohemagglutinin (PHA), concanavalin A (Con A), lipopolysaccharide (LPS), pokeweed mitogen (PWM), and dextran sulfate (Dx) were used to evaluate the status of various lymphocyte subpopulations. Neonates from the low zinc group gave no Con A response and limited responses to LPS and PWM (50%). Intermediate zinc pups responded satisfactorily to all mitogens except LPS (64%); moderate zinc pups responded normally. It was concluded that 5.8 microgram/g maternal dietary zinc, fed day 5-17 postpartum, is adequate for normal neonatal growth and mitogenic responses. Conversely, 1.6 microgram Zn/g caused neonatal growth retardation and reduced mitogenic responses without excessive mortality.
D000828:Animal Population Groups / Q000502:physiology*; D000818:Animals; D000833:Animals, Suckling / Q000033:anatomy & histology / Q000276:immunology / Q000502:physiology*; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D007774:Lactation; D008213:Lymphocyte Activation / Q000187:drug effects; D008221:Lymphoid Tissue / Q000033:anatomy & histology; D051379:Mice; D008934:Mitogens; D010835:Phytohemagglutinins; D011247:Pregnancy; D013154:Spleen / Q000276:immunology*; D015032:Zinc / Q000008:administration & dosage / Q000378:metabolism*
D008934:Mitogens; D010835:Phytohemagglutinins; D015032:Zinc