Aspiration pneumonia in neonatal foals
Bacterial pneumonia is a common cause of disease in young foals. One source of infection frequently associated with neonates is the aspiration of foreign material. However, with early recognition and treatment, this condition does not have to progress to more serious disease or death.
"Pulmonary disease is more serious than upper respiratory disease in neonatal foals," says Jonathan Palmer, VMD, Dipl. ACVIM, chief of Neonatal Intensive Care Service at the University of Pennsylvania School of Veterinary Medicine's New Bolton Center. "We see upper airway problems in neonatal foals lead to lower lung problems such as aspiration pneumonia that are more serious, more life-threatening and perhaps cause more problems later in life."
Aspiration of foreign materials into the lung is a serious problem for young neonates, especially when the reasons for the aspiration are not addressed. "If you don't do something so that they stop aspirating, it can result in a fatal pneumonia," Palmer says.Causes of aspiration pneumonia
"It's important for practitioners to know that if they see milk come out of a young foal's nose, there may be aspiration," Palmer says.
A few things can result in milk aspiration. Although very rare in foals (about 1 percent of aspiration problems), it may be caused by a cleft palate. More common is pharyngeal dysfunction and/or dysphagia, especially in premature, weak foals or septic foals. When the foal attempts to swallow, it doesn't seal its larynx, so milk will go down the trachea, as well as out its nose. Pneumonia develops when milk is aspirated into the lungs. Milk is a nonsterile substance with a multitude of bacteria present and is a perfect bacterial growth media.
Another reason for milk regurgitation from the nose is a failure to clear the cervical esophagus of milk after drinking. The condition may be associated with neonatal encephalopathy or esophageal dysmotility. "Severely affected foals may have a large volume of milk flow from their noses, yet, because the problem is in the esophagus and not the pharynx or larynx, they will be able to guard their tracheae, and milk will not be aspirated," Palmer says. Therefore, it is important to determine the reason for the milk regurgitation.
If aspiration of milk is suspected "you need to do something to stop it," says Palmer. While these conditions may be transient, the foal should not be allowed to continue nursing if aspiration is confirmed (moist trachea, abnormal lung sounds).