New methods for high-accuracy insect chitin measurement.

BACKGROUND: There is a growing interest in the use of insects in poultry, swine and aquaculture feed, as well as pet food applications. All insects produce chitin-based exoskeletons. With regard to chitin content, a precise determination in agricultural applications is crucial because it has favorable functional properties, although it is also difficult to digest for some species of livestock. Three measurement methods were compared to determine the most reliable method of chitin content determination in different insects and selected Hermetia illucens products: acid detergent fiber (ADF) provides the fiber content and the acid detergent lignin (ADL) additionally considers the catecholic compounds. Acetyl group measurement relates the acetate content to the chitin content. RESULTS: Comparing different insect species, the highest chitin value via ADF measurement was determined for the Tenebrio molitor larvae (155 g kg-1 ). Chitin values higher than 200 g kg-1 revealed that H. illucens residues are a much better valuable source of chitin. For the larval exoskeletons, a chitin content for all measurement methods of more than 350 g kg-1 was determined. In general, the ADF measurement is approximately 5% higher than the ADF-ADL and acetyl measurements. ADF-ADL and acetyl group determinations are approximately equivalent measurement methods. CONCLUSION: According to statistical analysis, ADF-ADL represents a compromise between accuracy and equipment demand and is a suitable method for determining the chitin content of both insects and their residues. © 2018 Society of Chemical Industry.

Gradual Provision of Live Black Soldier Fly (Hermetia illucens) Larvae to Older Laying Hens: Effect on Production Performance, Egg Quality, Feather Condition and Behavior.

Feather pecking is a key welfare challenge in laying hen husbandry. Feeding of live Hermetia illucens larvae could provide a possible solution to reduce feather pecking in hens. This research investigates effects of dispensing live H. illucens larvae to non-beak trimmed older laying hens on production performance, behavior and welfare. Control treatment hens were provided a commercial diet, while larvae treatment hens were provided live H. illucens larvae (using special dispenser) on top of a soy-free diet. Feather condition, production performance and egg quality were measured during the initiation (67 weeks age) and termination (78 weeks age) of the trial. Behavior of birds was monitored using video recording. Feed conversion ratio, body weight gain and egg laying parameters were similar for both treatments. At termination of the trial, larvae-fed hens exhibited better feather condition in comparison to control hens (p = 0.004). Behavioral observations indicated that larvae provision influenced the number of birds on floor during morning and afternoon hours. In conclusion, live H. illucens larvae could successfully replace soy in diets of older laying hens (in combination with local plant proteins). Provisioning of these insects also had a positive effect on the feather condition of laying hens with intact beaks.