ASSESSMENT OF NUTRITIONAL DEFICIENCIES AND TRACE MINERAL IMBALANCES IN CALVES RAISED IN MARGINAL PASTORAL REGIONS

Abstract

This study investigates the prevalence and impact of nutritional deficiencies and trace mineral imbalances in calves raised under extensive pastoral systems in marginal regions. A total of 80 pre-weaned calves from 12 smallholder farms were clinically evaluated, with blood, forage, soil, and fecal samples analyzed to determine micronutrient status, pathogen prevalence, and associated health outcomes. Biochemical analysis revealed widespread deficiencies in key trace minerals—zinc (72.4%), selenium (81.0%), copper (68.3%), and phosphorus (65.1%)—as well as fat-soluble vitamins A (69.8%) and E (83.5%). Such deficiencies were closely associated with clinical signs like rough hair coats, retarded growth, lameness and recurring diarrhea.  Forage and soil samples in grazing areas proved to be deficient in vital minerals, a fact that confirms the notion that the environment is the cause of the imbalances.  There was strong positive correlation of serum zinc, copper and selenium concentrations with average daily weight increase, highlighting the developmental importance of these nutrients.  Trace mineral deficiencies in calves also showed gastrointestinal infections, particularly Escherichia coli (43.1%) and Cryptosporidium (34.7%), demonstrating immunosuppressive effects of trace minerals deficiencies.  Such management interventions as the supplementing of minerals in the diet and the feeding of colostrum early were related to much lower rates of deficiency and disease.  These findings demonstrate that selective mineral supplement and pasture improvement are urgently needed in the not very productive areas.  Specific solutions to enhance the nutrition of calves during the first phases of life can significantly increase health, growth, and the productivity of the herd in the long term. It is a viable means of livestock producers in resource-constrained regions to progress sustainably.