Two Studies on Perches Presented at Welfare Meeting

From an oral paper presented at the European Symposium on Poultry Welfare last year, it emerged that hens rest on perches when they are provided and had higher feed efficiency. From a poster, it was concluded that the profile of the perch was more important than the material from which it was made in determining the use of perches by hens.

15 March 2010

5 minute read

Hens' Use of Perches

E. Valkonen from MTT Agrifood Research Finland and colleagues presented a paper on their study into the effects of perches in furnished cages on hen behaviour. They found that the hens used the perches to rest, if provided, and they were less likely to spend the night in the next area.

They explained that the aim of their study was to inspect the effects of perches in furnished cages (FC) on the behaviour, egg production and feed consumption of laying hens. Perches in conventional cages (CC) diminish activity and feed intake of laying hens. In FC, group size and total area are greater than in CC. These factors tend to increase the activity, and thus the energy requirement and feed intake of the hens.

A total of 352 hens were housed at 16 weeks of age in eight-hen FC. There were 44 cages together: 12 cages had perches all the time from the housing until the end of the experiment (control or P16); from 32 of the cages the perches had been removed. Perches were installed into 12 of these cages when the hens were 19 weeks of age (P19) and 20 cages remained without perches (NP). The experiment lasted for seven four-week periods or 28 weeks.

Feed intake and egg production were measured over each four-week period.

The behaviour of nine focal hens was observed using instantaneous sampling at five-minute intervals. The sampling took place during a two-week period at the age of 35–36 weeks, so that the observations of each focal hen covered one light period (14.5 hrs). The number of hens on perches and in nests was recorded at 17, 20, 23, 26, 34 and 42 weeks of age, on three consecutive days, and three times each day (at six and 11.5 hours after lights-on, and one hour after lights-off). The use of the litter box was recorded on the same days.

Statistical analysis (Chi2-test or ANOVA) were performed using SAS (SAS Institute Inc. Cary, NC).

The presence or absence of perches affected feed intake only during the first four-week period. From the 2nd to 4th period, feed conversion ratio was poorer in the group without perches than in the control group. No effects of perches were found on laying rate or egg production.

Hens without perches were more active (70 per cent of observations) than those with perches (61 and 63 per cent of observations in P19 and P16 groups, respectively). Hens in cages with perches sat more often than those without perches, whilst the hens without perches stood and walked more often.

During the observations in the dark, there were more hens in nests, in the cages without perches (20 per cent) than in cages with perches (12 per cent).

Based on the results of this study, Valkonen and colleagues concluded that perches reduce bird activity in FC, and help to reduce the number of hens spending their night in nests.

Refining Perch Design

In a poster, M. Cox of the Provincial Centre for Applied Poultry Research of the province of Antwerp in Belgium and co-authors from Wageningen UR in the Netherlands showed their results on the effect of perch material and profile on the use of perches by hens. They found a rectangular profile to be best, and that the material was of less importance.

At the Provincial Centre in Antwerp, different perches were tested during consecutive laying periods. The perches differed in materials used and in the profile of the perch. The perches were placed in enriched cages which housed 39 to 43 animals and different breeds were used through the different production periods.

The use of the perches was evaluated by observations after the lighting period in which the number of animals on the perches were counted.

The researchers commented that, although at first there seemed to be an impact of the material (wood, plastic or metal) on the occupation of the perch, further tests showed that the profile of the perch had more impact.

Results showed a higher use of perches when rectangular profiles were used.

In order to provide the birds with suitable perches and to make sure the perches are used, the right material and profile is necessary, concluded Cox and colleagues.

References

Cox M., K. De Baere, E. Vervaet, J. Zoons and T. Fiks-van Nierkek. 2009. Effect of perch material and profile on the use of perches. Proceedings of 8th Poultry Welfare Symposium, Cervia, Italy, 18-22 May 2009, p19.

Valkonen E., R. Rinne and J. Valaja. 2009. The effects of perches in furnished cages. Proceedings of 8th Poultry Welfare Symposium, Cervia, Italy, 18-22 May 2009, p18.