Bovine colostrum with egg powder to improve gut health (environmental enteropathy) in Zambian children with stunting and/or wasting (COZEE)

INTERVENTION: Intervention group Matched placebo sachet CONDITION: ; Nutritional, Metabolic, Endocrine Nutritional, Metabolic, Endocrine PRIMARY OUTCOME: Change in plasma soluble CD14 (sCD14) concentration, measured by ELISA. sCD14 is a monocyte‐derived marker of innate immune activation associated with exposure to lipopolysaccharide and is consistently elevated in environmental enteropathy. SECONDARY OUTCOME: ‐ Intestinal permeability ‐ transcutaneous fluorescein permeation, urinary lactulose recovery and lactulose‐to‐rhamnose ratio (baseline vs endline). ; ‐ Intestinal/buccal epithelial and immune‐cell populations and gene/protein expression (single‐cell and spatial RNA‐seq and proteomics; endline). ; ‐ Stool (and endline duodenal) microbiome composition and function (short‐ and long‐read sequencing; metabolomics). ; ‐ Biomarkers of inflammation and bacterial translocation in plasma and stool (e.g. faecal calprotectin, CRP, sCD14, EndoCAb IgG). ; ‐ Mucosal morphometry and histological EE score on duodenal biopsies (endline). ; ‐ Anthropometry ‐ weight, length/height, MUAC, fat mass and fat‐free mass (baseline vs endline). ; ‐ Glycyl‐sarcosine (dipeptide) absorption (baseline vs endline). ; ‐ Gut digestive capacity ‐ 13C‐spirulina breath test (baseline vs endline). ; ‐ Nitric oxide synthesis from arginine (15N‐nitrate in urine; baseline vs endline). ; ‐ Intestinal amino‐acid absorption (13C‐/2H‐labelled amino acids). ; ‐ Heavy‐metal exposure (including zinc) in hair and toenails (endline). INCLUSION CRITERIA: 1. Age between 6 and 60 months, of either sex. 2. Stunting (length/height‐for‐age Z‐score < ‐2) and/or wasting (weight‐for‐length/height Z‐score < ‐2), per WHO Child Growth Standards, confirmed on two separate screening occasions at least one month apart. 3. Parent, primary caregiver or guardian able and willing to give written informed consent. 4. A subgroup of 25 children will additionally have been small for gestational age (SGA) at birth.