Lakeside Veterinary Services

12626 Cemetery Rd
Wolcott, NY 14590


Excerpted from 
When Navel Dipping, Gentler is Better 
Modern Horse Breeding, February 1995.

Strong iodine is not the solution to umbilical health. Dipping the umbilical stump of a newborn foal is a routine management procedure on breeding farms. Yet some managers have long observed that stronger solutions sometimes seem to do more harm than good. Now, research from the University of California-Davis School of Veterinary Medicine has confirmed that when it comes to navel dipping, gentler is better.

A team of researchers compared dipping the navel stump in four common bactericidal solutions: 2% iodine, 7% iodine, 1% povidone-iodine solution and 0.5% chlorhexidine solution. The dipping was done immediately after birth and again six to eight hours later. A fifth group of control foals was not treated with any solution.

The researchers looked carefully at the various solutions' abilities to reduce the type and number of bacteria which typically colonize the umbilicus. They viewed the area with ultrasound to examine the way in which the umbilical vessels regressed and whether they were beginning to abscess. In addition, they followed the progress of separation and atrophy of the umbilical stump and compared that process with the development of complications which may have arisen due to invasion of bacteria.

The results indicated that 7% iodine, while extremely effective in eliminating bacteria, did its job all too well. The strong tincture opened the door for infection due to rapid drying out of the stump, sloughing of adjacent tissue, and development of a long tail, giving bacteria a free ride into the bloodstream and opening the door to abscessing, systemic infection, and navel ill. Instead, the more gentle solution of chlorhexidine, diluted with water in one-to-four solution, proved equally effective in controlling bacteria but without the undesirable side effects.

The results of the study were presented by John Madigan, DVM, at the Sixth International Symposium on Equine Reproduction in Brazil.