Tre metoder att förse värphöns (Gallus gallus domesticus) med levande larver av svart soldatfluga (Hermetia illucens) : effekter på födosöksbeteende samt produktionsparametrar

Feather pecking is a major welfare issue in commercial egg production. Feather pecking is thought to be a form of re-directed foraging pecking behaviour. When hens are deprived of the necessary conditions to perform foraging behaviour the risk of developing feather pecking increases. For this reason, promoting increased foraging behaviour has been used as a way to reduce feather pecking. There is some evidence that the provision of live Black soldier fly larvae can increase foraging behaviour in broilers and layers. However, it is not clear whether there are any differences between providing the larvae over a large versus a small area or for a longer time period versus all at once. For these reasons, the aim of this thesis was to investigate the effects of providing live Black soldier (20% of the daily nutritional need in DM) on foraging behaviour, growth and production in laying hens. The larvae were provided using one of three feeding methods: (1) with a bucket with holes (Bucket), hanging above the litter area, to provide larvae at a slow rate throughout the day, (2) larvae scattered on the litter area in the morning (Scatter) and (3) larvae provided in dedicated feeding troughs in the morning (Trough). A total of 90 laying hens were randomly assigned to one of the three treatments (6 pens per treatment, 5 hens per pen). Data was collected over 9 weeks and events of foraging, active behaviour, feather pecking and agonistic behaviour was registered during one day every other week using video cameras. On the day of recording, video cameras recorded each pen 1 hour before, the hour after and 5 hours after a provision of larvae which were delivered daily at 08.00 (standard time). Data for production parameters (feed consumption, egg production, egg weight, hen weight and weight of the intestine) were also collected throughout the study. The results showed that all methods managed to promote foraging when comparing the periods before and after a provision of larvae (P < 0.05). However, hens in the Bucket and Scatter treatments spent significantly more time foraging during the hour after a provision of larvae as compared to the hens receiving larvae in a trough (P < 0.05). Furthermore, hens in the Bucket treatment were more active compared to hens in the Trough treatment during the same period (P < 0.05). Both feather pecking and agonistic behaviour occurred too few times for any statistical analysis to be performed. All production parameters measured were unaffected by the feeding method. In conclusion, a provision of live black soldier fly larvae can increase the levels of foraging in laying hens and the method of providing it will affect the outcome. Methods where larvae is provided for a longer time period or being scattered over a larger area seems to be most advantageous compared to providing the larvae in troughs