Polyunsaturated fatty acids (PUFAs) and vitamin D show potential as dietary supplements to improve skeletal health in layer hens.
While cage-free housing allows for increased bird movement and expression of natural behaviors, keel bone fractures often increase in prevalence in the environment due to collisions and movement between tiers within the system.
The effects of PUFAs and vitamin D on layer keel bone health were discussed by Dr. Prafulla Regmi, University of Georgia Assistant Professor of Poultry Science, at the 2022 Multi-State Poultry Feeding and Nutrition Conference and Danisco Animal Nutrition & Health’s Technical Symposium.
Regardless of housing system, there are going to be keel bone fractures in flocks, explained Regmi. However, a higher prevalence of keel bone fractures has been noted in cage-free housing systems.
Common sources of PUFAs are fish and flaxseed oils. Fish oil is generally rich in eicosatetraenoic acid (EPA) and docosahexaenoic acid (DHA) while flaxseed oil contains alpha-linolenic acid (ALA), he added. Research has proven that vitamin D assists in increasing bone strength.
To examine the effects of PUFAs, a collaborative study was launched by Michigan State University, Purdue University and the University of Georgia. The aim of the study was to examine the effects of PUFAs and vitamin D on bone metabolism in layer hen diets and to determine if birds supplemented with higher levels of PUFAs or vitamin D would have improved bone health.
Approximately 3,500 Lohmann Brown-Lite pullets were utilized. The birds were housed on the floor until 17 weeks of age, then moved to cage-free housing. Treatments included a control diet, a flaxseed oil diet, a fish oil diet and a vitamin D diet, explained Regmi.
Birds fed the fish oil and vitamin D diets had greater bone density, keel bone volume, bone mineral content and keel condition compared to hens fed the flaxseed oil and control diets.
Birds fed the vitamin D diet had the heaviest body weights and higher case weights. The fish oil diet yielded the lowest case weights. Improved feather coverage was seen in birds fed the flaxseed oil and vitamin D diets.