Why does a rat have drooling? - briefly
Rats produce excess saliva when they are stressed, suffer from illness, have dental problems like overgrown incisors, or are exposed to toxic substances.
Why does a rat have drooling? - in detail
Rats produce saliva continuously as part of normal digestive physiology; the glands secrete fluid that moistens food, begins carbohydrate breakdown, and protects oral tissues. When secretion exceeds the capacity to swallow, visible drooling occurs.
Several conditions increase salivary output or impair swallowing:
- Stress or fear: Acute activation of the sympathetic nervous system stimulates the submandibular and sublingual glands, leading to excess fluid that the animal cannot control.
- Dental problems: Overgrown incisors, malocclusion, or periodontal disease cause oral discomfort, prompting heightened salivation and reduced ability to close the mouth.
- Neurological impairment: Lesions affecting the brainstem nuclei that coordinate swallowing (e.g., pontine or medullary damage) disrupt the normal rhythm of saliva clearance.
- Toxic exposure: Organophosphate pesticides, heavy metals, or certain rodenticides inhibit acetylcholinesterase, resulting in cholinergic overstimulation of salivary glands.
- Respiratory infection: Upper airway inflammation from pathogens such as Mycoplasma pulmonis can trigger reflex salivation and hinder effective swallowing.
- Gastrointestinal upset: Nausea or gastroenteric irritation stimulates the vagus nerve, increasing glandular output.
Diagnosis requires observation of droplet volume, assessment of oral health, and evaluation of behavior for signs of distress or neurological deficits. Laboratory analysis may identify toxins or infectious agents, while radiography can reveal dental abnormalities.
Management targets the underlying cause: stress reduction, dental trimming, antimicrobial therapy for infection, antidotes for toxic exposure, or supportive care for neurological injury. Hydration and a diet of easily masticated food help maintain fluid balance while the condition resolves.