Suggested further research

The study highlighted awareness of the importance of footpad health on breeder welfare. However, due to a number of unanswered questions it is essential to investigate the subject further. Elevated structures as a means of enhancing broiler welfare in commercial situations also merit more attention in future research. Some more specific suggestions for research are listed below:

 Global assessment of breeder footpad health and the effect of footpad lesions on breeder production

 The influence of irritants in litter and regular addition and turnover of litter on the footpad health of broiler breeders

 The impact of slats and other possible risk factors on breeder footpads

 Further studies on the threshold moisture of peat bedding with regard to contact dermatitis

 The use of peat as broiler bedding under a wider variety of housing conditions  The effect of peat bedding on broiler litter-directed behaviour that possibly assists

in maintaining good litter condition in a commercial environment

 Changes in peat pH over time during production period, and effects of the lower initial pH of peat on bacterial composition in litter and influence on footpad health  Possible adverse consequences of dry and friable litter on aerial dustiness,

particularly regarding welfare and respiratory diseases

 Besides litter quality, other risk factors inducing hock burns in Finnish conditions  More experience of perches and platforms in commercial broiler houses: the use of

different kinds of equipment and their effects on litter condition (also other than peat litter) and contact dermatitis

 Perching on different types of elevated structures by broiler breeders and possible positive effects on their welfare

 The motivation behind the willingness to use platforms by broilers through the entire growing period, even near slaughter age

 On-farm testing and the modification of inexpensive elevated structures, that are practical for farmers to handle and attractive to broilers

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7 Conclusions

Although dry and friable litter in breeder houses was associated with healthier footpads, good litter condition alone appears insufficient to maintain breeder footpads healthy for their entire life. In broiler production, the impact of farmer on the severity of contact dermatitis exceeded the effect of litter condition. Broilers on peat bedding had better footpad and hock skin health compared with when on wood shavings and ground straw. However, litter condition and moisture were unable to fully explain the differences. Our result indicates that broilers are motivated to use elevated structures, and platforms are better suited for broilers than conventional perches. Access to platforms most likely enables more versatile movement that may promote gait and leg health, without compromising litter condition and footpad health.

1. Hypothesis: contact dermatitis and breast blisters in breeders become more common and severe with age

The condition of breeder footpads deteriorated as birds aged. At slaughter 64% of the breeders had severe lesions, indicating compromised welfare. However, further studies are needed to determine if the situation is comparable in other countries. Hock burns and breast blisters were rarely detected. (Study I)

2. Hypothesis: litter condition in broiler and breeder houses deteriorates over time, and inferior litter condition and higher moisture are associated with impaired footpad health in broilers and breeders

In breeder houses litter condition deteriorated, but litter moisture decreased towards the end of the production period. In broiler houses, changes in litter condition and quality depended on the litter material. Litter condition evaluation revealed no substantial differences between breeder and broiler houses. Maintaining litter in a dry and friable condition is crucial for good footpad health. However, further risk factors, such as represented by slat area, appears to affect the footpads of breeders. Thus, sustaining satisfactory litter quality alone is not enough to ensure a good level of footpad health in breeders. In broilers, the impact of farmer on contact dermatitis severity exceeded the effect of litter quality. (Study I & II)

3. Hypothesis: peat was expected to provide the best litter condition in broiler houses and promote the most favourable footpad and hock skin health in broilers, due to its low pH

Broilers on peat litter exhibited less contact dermatitis compared with when on wood shavings and ground straw. Footpad and hock skin health were inferior on wood shavings than on peat, without there being differences in litter condition and moisture at the end of the production period. Moreover, the lack of difference in end moisture between ground

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straw and peat still resulted in poorer litter, and inferior footpad and hock skin condition on ground straw. Hence, these results suggest that the relationship between litter condition, moisture and contact dermatitis may be more complex than previously stated. In contrast to our hypothesis, low pH cannot explain the better footpad health on peat. Furthermore, the results underline the importance of the farmer’s ability to manage litter conditions, regardless of the chosen litter material. (Study II)

4. Hypothesis: extra equipment in broiler houses obstructs the airflow, and thus negatively affects litter condition, and possibly also footpad and hock skin health

The study indicated no effects of additional equipment, in the form of elevated platforms, on broiler footpad health and peat litter condition and quality in a commercial production environment. (Study II)

5. Hypothesis: platforms appear more popular among broilers than perches

In commercial broiler houses the birds used elevated platforms with ramp access eagerly but the use of perches was negligible. The advantages of traditional perches for broilers should be re-evaluated because they remained largely unused. However, our prototype platforms show good potential as environmental stimuli for broilers. (Study III & IV)

6. Hypothesis: perches and platforms could increase versatile locomotion sufficiently to improve broiler walking ability and leg health

Adding attractive equipment, such as elevated platforms, to broilers’ environment may promote their gait and leg health. In this study, access to platforms may have enabled more versatile movement, such as walking forward, up and down, grasping by feet, and jumping, that could have positively influenced walking ability and contributed to fewer and milder TD lesions. (Study IV)

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