Metabolic responses of chronically starved horses to refeeding with three isoenergetic diets.

This study explores how chronically starved horses reacted metabolically when reintroduced to three different diets that held the same energy levels. The overall finding suggests that clinically normal but emaciated horses can be satisfactorily rehabilitated through steady refeeding with a diet high in forage.

Research Methodology

• The research involved an uncontrolled clinical trial with 22 mature mixed-breed horses that were emaciated but otherwise clinically normal.
• The horses in the study were given one of three diets: alfalfa hay, oat hay, or a half-and-half mixture of oat hay and commercial ration.
• The diets’ digestible energy was increased gradually over the refeeding period.
• The team obtained one preprandial (before meal) and four postprandial (after meal) blood samples each day. These samples were analyzed to record red blood cell count, glucose, insulin, free fatty acid, total bilirubin, 2,3-diphosphoglyceric acid, phosphorus, magnesium, calcium, sodium, and potassium concentrations.
• Other daily measurements included the horses’ body weight, fecal output, and the amount of feed and water they consumed.
• The team employed the repeated-measures ANOVA methodology to examine daytime and dietary effects of the three diets during 10-day trials.

Research Findings

• Of the 22 horses, 19 survived. The three horses that did not (two on the alfalfa diet and one on the mixed diet) died of either metabolic or gastrointestinal problems.
• The study observed that there were increasing temporal effects with serum concentrations of glucose, insulin, magnesium, calcium, and sodium. On the other hand, the concentration of free fatty acid, 2,3-diphosphoglyceric acid, and phosphorus decreased over time.
• Diet impacted the serum levels of glucose, insulin, magnesium, and potassium. Serum phosphorus and free fatty acid concentrations saw sizable dips during the first five days of refeeding with all three diets.
• For horses on the alfalfa hay diet, serum magnesium concentrations improved. This was not the case for horses fed oat hay or the combination diet.
• Horses receiving the alfalfa and oat hay diets had lower post-meal glucose and insulin concentrations compared to those receiving the mixed diet.
• Horses fed with oat hay alone ate 92% of the feed offered, whereas those given alfalfa hay or the mixed diet ate about 98% of the offered feed.

Conclusion of the Study

• The study concludes that clinically normal but emaciated horses can be successfully rehabilitated.
• This is achieved through gradually reintroducing a diet high in forage content. Alfalfa hay yielded particularly strong results.