With all the attention and care we give our chickens, and as much as we would like to see them live long, healthy lives, we might be unintentionally contributing to their premature demise. Our chickens have worries Grandma’s chickens never faced: getting fat.

Fully grown, mature hens should not continue to gain weight. Just like humans, however, if your bird consumes more calories than it expends, it will. Given a chicken’s unique biology, it first retains the weight in the form of excess fat in the abdomen and liver. As the hen continues to gain weight, fat will eventually become palpable behind the tip of the keel bone between it and the vent. Unfortunately, by the time this abdominal fat pad is noticeable (visually or palpably), serious liver damage has already occurred.

Obesity can cause decreased fertility, frequent multiple-yolked eggs, egg-binding and prolapsed vent. The two most common obesity-related causes of death in laying hens are heat stroke and fatty liver hemorrhagic syndrome, commonly referred to as FLHS. According to Mike Petrik, DVM, MSc, a laying hen veterinarian in Ontario, Canada, “Obesity causes sudden death from FLHS, where the liver fills with fat, becomes fragile, splits and causes the bird to bleed to death.” A minor impact to the chest or the abdominal pressure generated during egg-laying is enough to cause an obese hen’s fragile, fat-filled liver to shatter, causing her to bleed to death internally.

With excess fat in its abdomen, hot weather becomes life threatening to a hen. Without sweat glands, the chicken relies upon respiration to regulate internal temperature, but when abdominal fat limits its ability to breathe properly in high temperatures, the hen can die from heat stroke within a matter of minutes.

Fortunately, with a few common-sense modifications to their lifestyle, obesity can be prevented and controlled.

1. Feed a Balanced Diet

“Feeding a well-balanced ration with plenty of B vitamins and choline help the hens metabolize fat more efficiently,” Petrik says. Provide a commercially prepared feed, as they’ve been carefully formulated by poultry nutritionists who monitor the composition of ingredients to ensure that a hen’s daily nutritional requirements are met. I strongly recommend against dabbling in assembling homemade feeds. Poultry nutrition is complicated, and there is much more to it than simply getting the ingredients right. Imprecise calculations and missing, incorrect, or improperly stored or prepared ingredients can all result in obesity, as well as other behavioral and health issues.

2. Monitor Chicken Weight

Fully grown hens should maintain a consistent weight. Changes in weight in a mature hen signify a problem. Weigh your hens regularly, -waiting until after dark when they’ve gone to roost, as their night vision is poor and they’re less likely to object to handling when half-asleep. Document the results and compare them to previous weigh-ins. If they’re losing weight, there’s likely a problem; consult your local poultry specialist or vet for other signs of distress. If they’re gaining weight, they’re being overfed.

3. Limit Treats

Treats, snacks and table scraps can replace a portion of the daily, essential dietary requirements found in quality layer rations. However, excessive treats, even healthy ones, can lead to obesity and other health complications, including. It’s no secret that we enjoy spoiling our chickens with treats. We get a charge out of seeing them run to greet us at the sight of a treat container or the sound of the back door opening, but moderation and common sense should be the guide in treat selection and quantity in order to keep their weight under control and preserve their health.

4. Encourage Exercise

Free-range chickens are less likely to be obese than confined chickens—exercise burns calories. But not all chicken keepers are able to or choose to free-range their flocks. Hens that do not free-range should be given as large a yard as possible to maximize their ability to exercise. The bare minimum sized yard or run generally agreed upon is 10 square feet per bird, but more space is always better.

If a mature flock is gaining weight, the solution is simple: Reduce the daily dietary intake by 5 percent to 10 percent, and increase opportunities to exercise until the goal weight is reached.

While Grandma’s nameless chickens were destined for the soup pot, they unquestionably benefited from a more natural, healthier lifestyle than most pet chickens today. They ate like kings from nature’s buffet of living food, customizing the menu to their nutritional needs without being enticed by treats from well-intentioned humans. The majority of today’s pet chickens don’t forage the day away on lush pastures, due to either space constraints or their keeper’s desire to protect them from predators. As a result, their pedometers don’t rack up the miles and their diets are controlled artificially, not by them. While our over-feeding is unintentional, the potential costs to our chickens are great. By being aware of the need for balanced rations, moderate treat offerings and as much room to exercise as possible, we can maximize our chickens’ health and provide them with the best opportunity at living a long life.

This article was excerpted from the March/April 2014 issue of Hobby Farm Home.