4) They Experience Sadness
Animals also have emotions just like humans and they also do get sad. There will be just a few reasons for dogs to feel like that, but may be very sentimental and sensitive. For example, when they miss you or more often when they lose their pet companion or while you are in distress. So usually, the signs of expressing sadness are observed as lose in appetite, too little or excessive sleep and uneasiness. And these behavioural changes may even last from weeks to months.