What is Canine Night Blindness?
Canine night blindness refers to a significant decline in a dog’s vision in low-light or nighttime environments, making it difficult to see surrounding objects clearly. Night blindness is usually caused by damage to the rod cells in the retina, which are responsible for vision in dim lighting. Dogs with night blindness may show reluctance to move, hesitation, or bumping into objects during dusk or nighttime.
I.What is Congenital Stationary Night Blindness (CSNB)?
Congenital Stationary Night Blindness (CSNB) is a hereditary condition that affects a dog’s ability to see in low-light or dark conditions from birth. Unlike progressive forms of night blindness, the condition is stationary, meaning it does not worsen over time. It is typically caused by defects in the retina, specifically in the rod cells that are responsible for vision in dim lighting.
Dogs with CSNB will often exhibit symptoms such as difficulty seeing in low light, hesitation or difficulty navigating in dim or dark environments, but their vision is generally normal in bright conditions. The condition is inherited, and some breeds, like the American Cocker Spaniel, Austrian Shepherd, and Kerry Blue Terrier, are more prone to it.
CSNB does not lead to complete blindness, and affected dogs usually maintain good vision in daylight, but their ability to adapt to darkness is severely impaired. The condition is typically diagnosed through a combination of clinical symptoms and specialized tests by a veterinarian or veterinary ophthalmologist.
II. What are the Symptoms of CSNB
1.Vision Issues
Poor Night Vision: This is the primary symptom of congenital stationary night blindness. In dimly lit environments, such as outdoors at night without lights or indoors in poorly lit rooms, the dog experiences a significant decline in vision, making it difficult to see surrounding objects. The dog becomes cautious in its movements, reluctant to move freely like during the day, and may bump into furniture or other obstacles.
Normal Day Vision: In contrast to poor night vision, the dog’s vision is generally normal during the day or in well-lit environments. The dog can see clearly, play, recognize its owner, and navigate the surroundings with behavior similar to that of a healthy dog.
2.Ocular Manifestations
Retinal Abnormalities: Through professional ophthalmic examinations, characteristic changes in the retina can be identified in dogs with congenital stationary night blindness. For instance, certain cells in the retina may exhibit morphological abnormalities and disorganized arrangement. These changes affect the dog's perception and conduction of light in low-light conditions, leading to the emergence of night blindness symptoms.
Nystagmus: Some affected dogs may also exhibit nystagmus, which is an involuntary, rhythmic oscillation of the eyeballs. This ocular nystagmus is typically more pronounced when the dog is in a dimly lit environment or trying to see objects in low light. It occurs because the dog's visual system cannot function properly in low-light conditions, causing the eye muscles to lose stable visual signal regulation and resulting in a compensatory movement.
3.Behavioral Changes
Reluctance to Enter Dark Areas: Due to poor vision in the dark, dogs will instinctively feel fear or uneasiness towards dark environments. Consequently, they will try their best to avoid entering places with dim lighting. For example, they are unwilling to go into the yard at night or enter a room without the lights on.
Dependence on Other Senses: To compensate for the deficiency in vision, affected dogs will rely more on their other senses to perceive the surrounding environment during the night or in low-light conditions. Their sense of hearing and smell will become sharper, and they will judge whether there are dangers or familiar things around by listening to sounds and sniffing odors.
III. The Main Causes to Develop CSNB
The main cause of Congenital Stationary Night Blindness (CSNB) in dogs is genetic factors. The specific reasons are as follows:
1.Genetic Gene Mutations: Congenital Stationary Night Blindness is a hereditary disease, usually caused by the dysfunction of rod cells in the retina that are responsible for night vision. This disease is caused by mutations or defects in specific genes, which may affect the retina's ability to perceive and adapt to light. It is usually an autosomal recessive inheritance, meaning that only when both parents pass on the mutated genes will the offspring show the symptoms.
3.Retinal Development Abnormalities: Dogs with Congenital Stationary Night Blindness (CSNB) may have underdeveloped or dysfunctional rod cells or photoreceptor cells in their retinas. These cells are responsible for providing vision in low-light conditions. This developmental issue of the retina leads to a significant decrease in the dog's vision at night or in low-light conditions.
4.Susceptibility in Specific Dog Breeds: Some dog breeds are prone to inheriting this disorder, such as the American Cocker Spaniel, Kerry Blue Terrier, Australian Shepherd, Manchester Terrier, and Shar Pei. Since these dog breeds are more likely to carry the relevant mutated genes at the genetic level, they are more susceptible to Congenital Stationary Night Blindness.
Because this condition typically manifests at birth and does not worsen over time, it is referred to as "stationary." Although dogs have difficulty in dark environments, their daytime vision is usually normal.
V. Food and Supplements Recommended for Night Blindness
Preventing night blindness in dogs can be achieved by providing a diet rich in nutrients that are beneficial for eye health, helping to protect retinal health and improve low-light adaptation. Here are some key nutrients and foods that can help prevent night blindness:
1.Vitamin A: Vitamin A is an essential component of rhodopsin in the retina, and a deficiency can lead to night blindness. Foods rich in vitamin A include carrots, pumpkin, liver, and sweet potatoes. Incorporating these foods in appropriate amounts can help support retinal health.
2.Vitamin C and Vitamin E: These antioxidants can protect the eyes from the damage caused by free radicals and slow down the aging and degeneration of retinal cells. Some foods rich in Vitamin C and E can be chosen, such as blueberries, spinach, and sweet peppers.
3.Lutein and Zeaxanthin: These are antioxidant substances that have a protective effect on the retina. They exist in dark green vegetables (such as spinach and kale) and help slow down eye degeneration and support healthy low-light vision.
4.Omega-3 Fatty Acids: Omega-3 fatty acids (especially DHA) are beneficial for retinal health and can help slow down vision degeneration, particularly in older dogs. Foods rich in Omega-3 include fish oil, flaxseed oil, sardines, and salmon.
5.Zinc: Zinc is an essential mineral for eye health and helps maintain the normal function of the retina. Foods rich in zinc include lean meats, pumpkin seeds, and seafood.
When adding these foods to your dog's diet, attention should be paid to reasonable combination and avoiding excessive intake. Meanwhile, there are specialized nutritional supplements for eye health on the market, which contain the above-mentioned nutrients. They can be supplemented appropriately under the guidance of a veterinarian to meet the needs of the dog.
Best supplements recommended for vision health . For more information, please click the pictures.
Noora 8 in 1 contains vitamin E and vitamin C, and Selenium, good for vision health for you pets. .
Advantages: Specifically designed for dogs, this supplement provides comprehensive health support, including for joints, muscles, cardiovascular health, skin, gut, vision and immune system. It contains a number of active ingredients, including Glucosamine and MSM. Other active ingredients include Boswellia Extract and Grape Seed Extract. Moreover, the product contains a variety of vitamins and mineral essential to maintaining the health of dogs. Vitamins C and E act as antioxidants and protect cells against damage caused by free radicals. Hyaluronic acid aids in skin and joint health. These ingredients provide the necessary nutritional support to help dogs maintain health and vitality.
Appearance/Taste: This product is available in chewable tablets that have a chicken liver taste to make it more appealing for dogs.
Size: 2.5 grams each tablet, 50 tablets in each bottle, a total of 125g (4.41 )
Noora Daily Multi contains vitamin A vitamin C and vitamin E, good for vision health
Advantages: Noora Daily Multi is a comprehensive health supplement designed to complement today's dog diets by providing 21 essential nutrients. It supports overall health maintenance and well-being in dogs of all ages, ensuring they receive a balanced intake of vital vitamins and minerals.
Appearance/Taste: The supplement comes in a vegetable flavor, which is appealing to dogs and encourages consumption.
Size: Each chew is formulated to be 3.5 grams, making it a manageable size for dogs to chew comfortably.
Quantity: 60 chews in each bottle, a total of 210 g (7.41 oz).
