Labrador Retriever (Detailed Introduction)

PM2.5 ‘s harm to humans has already become obvious, but you would never think that PM2.5 harms dogs even more. The main reason is that dogs’ defense systems are more fragile than humans’, and just by breathing, they inhale more harmful substances than humans.

We live together with dogs on land surrounded by gases. Breathing gas allows our life activities to be maintained and continued, and once breathing stops, life ends. Humans and dogs, both mammals, are created by God with a clever respiratory system that exchanges our body’s gases with the external atmosphere, absorbing oxygen to provide nutrients to cells and exhaling carbon dioxide and other wastes. At the same time, three lines of defense are set up to resist harmful molecules in the air.

The spiral structures inside the nasal cavity and branched trachea prevent foreign objects from entering deeply into the lungs, forming the first line of defense; the nasal cavity, pharynx, trachea, bronchi, and lung surfaces are rich in mucous membranes whose cilia trap particulate matter and clean the inhaled air, while also heating and humidifying the air; the mucus contains immunoglobulins and lysozyme, helping the lungs resist bacterial invasion. However, when God created such a precise respiratory organ, He surely did not expect that an invisible substance called PM2.5 would gradually become a deadly killer.

PM2.5 affects gas exchange in the lungs, causing various respiratory symptoms and even lung cancer. It can also further pass through the alveoli into the blood and travel to other organs. It deposits in blood vessels causing vascular sclerosis, thus endangering cardiovascular health.

Besides the common characteristics of advanced mammals, dogs have unique structural and physiological traits compared to humans.

1. Poor filtration due to no nose hairs

Like most animals, dogs do not have nose hairs. Their ability to filter and clean large dust particles is weaker than that of humans.

2. Highly sensitive sense of smell

Dogs explore the world mainly through smell and hearing. Their olfactory organs are extremely developed, with olfactory nerves covering the nasal mucosa. Their sense of smell is over 1200 times stronger than humans’. Searching, tracking, and social interaction all involve constant and serious smelling. This “overuse of the nose” increases the chance for dust and bacteria to sneak in while acquiring useful information.

3. Low body position easily inhales car exhaust

The dog’s low height means their breathing zone is close to car exhaust levels. Dogs are more affected by car exhaust and road dust than humans.

4. Mouth breathing

When walking dogs, they tend to breathe through their mouths. Without passing through the narrow and complex nasal filtering and cleaning system, polluted air directly enters the airway through the mouth, greatly increasing the degree of damage. Therefore, dogs are more vulnerable to the threat of PM2.5. Caution and protection are necessary during smoggy weather.