Horse News & Views - July 2009

• Poison ivy (Toxicodenron radicans) is a perennial shrub. It contains the highly irritating, allergic, phenolic compound, urushiol. Animals are rarely affected by poison ivy but can spread it to humans from their contaminated hair. Urushiol is soluble in alcohol but not soluble in water. Therefore, wiping with an alcohol cloth is a better method of decontaminating the hair coat than using water.
  
  

• Occasionally, geldings exhibit stallion-like behaviour and owners question whether they have a retained testicle, otherwise known as cryptorchid, rigling or rig. Your veterinarian, with the aid of the laboratory, can help to differentiate between castrated males and cryptorchids by evaluating the increase in serum testosterone concentration when stimulated with human chorionic gonadotrophin (HCG).
  
  

• Plants of the brassica family, which include kale, rape, cabbage, broccoli and mustard, are toxic to livestock. Brassicas contain a number of toxic chemicals, including glucosinolates, which are present in young growing plants and seeds at the highest concentrations. When consumed, they can cause goiter, hypothyroidism, poor growth rates and reproductive failure. Glucosinolate metabolites can also cause colic and diarrhea. Herbicides may be required to control mustard from contaminating hay and pasture fields in the first year after seeding.