One of the best meat sources that dogs can eat.
It’s lower in calories and higher in protein than other kinds of liver.
Chicken is nutritionally dense.
Good source of vitamin A, B1, B2, B3, B5, B9, B12, C , E, Coenzyme Q10, selenium and iron.
All B vitamins help the body to convert food (carbohydrates) into fuel (glucose), which is used to produce energy.
These B vitamins, often referred to as B-complex vitamins, also help the body metabolize fats and protein.

Chicken liver provides 11.62 mg of CoQ10 in every 100 g, making it one of the highest food sources of CoQ10.
The CoQ10 found in liver is twofold in important uses! It improves joint health, which is especially beneficial for large breeds and dogs who suffer from arthritis. 

Secondly, Coenzyme Q10 is good for heart health; increasing the “good cholesterol” in your dog’s body.

It also helps to lower blood pressure and protect muscle tissue in the heart during cardiac trauma. Fatty acids improve coat health and all those B vitamins help your dog fully reap the benefits of the fat and protein found in liver. Since it is so densely packed with iron, it’s also effective in treating anemic animals.
For dogs with frequent colds and diarrhoea, we can take advantage of the high vitamin A content in chicken liver,
to enhance the resistance of dogs and improve intestinal function.
Chicken liver is rich in protein, can help them absorb nutrients and strengthen their health.

Chicken liver is an excellent source of many vitamins, minerals, and health boosters.

Triples your daily value of Vitamin B12 which supports red blood cells and slows anemia.

Brimming with Vitamin A in the form of retinol which assists good eyesight.

Full of riboflavin that supports health tissues.

Packed with selenium which supports the thyroid.

Supports an overall immune system.

High in protein content that promotes healthy hair, skin, and nails.

High in phosphorus that helps keep teeth and bones healthy.

Resources:

https://www.mountsinai.org/health-library/supplement/vitamin-b2-riboflavin

https://www.purepetfood.com/help/can-dogs-eat-liver

https://www.ctpetfood.com/pet-food-industry-news/chicken%20liver.html

https://discover.grasslandbeef.com/blog/chicken-liver-nutrition/

https://simplefoodproject.com/organ-meats/

Image: USDA Database