Influence of age and breed of equid on plasma copper and zinc concentrations.

The research article discusses the impact of age and breed on copper and zinc concentration levels within the blood plasma of healthy horses. The findings reveal notable differences in these levels between newborn foals and mature horses, as well as between different breeds.

Study Methodology and Participants

• The study examined 215 clinically healthy horses belonging to various ages and breeds.
• The tests performed measured the activities of plasma ceruloplasmin and the copper (Cu) and zinc (Zn) concentrations in the animals’ plasma.

Results: Copper Concentrations

• All newborn foals showed lower copper counts compared to adolescent and mature horses, regardless of their breed.
• Foals of the Standardbred-Thoroughbred (STD-TB) breed had an average plasma Cu concentration of 2.9 mumol/L – about a sixth of the copper concentrations observed in mature horses.
• Newborn draft-cross foals showed higher plasma Cu concentrations (4.6 mumol/L) than STD-TB foals, although this was only a fifth of the levels seen in their mothers.
• Regardless of age, draft-cross horses had Cu concentrations in their plasma that were 15% to 40% higher than those found in STD-TB horses. This level was comparable to that in Quarter Horse yearlings.

Results: Zinc Concentrations

• The plasma Zn concentrations of newborn and one-week-old STD-TB foals were found to be 30% to 80% higher than those found in the yearling and mature STD-TB horses.
• No differences were observed between the Zn concentration in draft-cross newborns and their mothers’ plasma.
• Both newborn and mature draft-cross horses’ plasma Zn concentrations were 22% higher than those measured for any other horse breeds.

Plasma Ceruloplasmin Activities

• The study found a curvilinear relationship between plasma ceruloplasmin activities and plasma copper concentrations, indicating a complex non-linear correlation between the two.

Key Findings and Implications

• Given variations in copper and zinc concentrations across different horse breeds and ages, these factors should be considered when interpreting plasma Cu and Zn concentrations in equids.
• The findings can be relevant for understanding nutritional requirements and managing health issues related to copper and zinc deficiency or excess in different horses.