Does nest size matter to laying hens?

Abstract

13Laying hens in loose housing systems have access to group-nests which provide space for several hens at 14 a time to lay their eggs. They are thus rather large and the trend in the industry is to further increase the 15 size of these nests. Though practicality is important for the producer, group-nests should also cater to the 16 egg-laying behaviour of hens to promote good welfare. One of the factors playing a role in the 17 attractiveness of a nest is the amount of enclosure: hens prefer more enclosure when having a choice 18 between different nest types. The aim of this study was to investigate if hens prefer smaller group-nests to 19 lay their eggs given that they may seem more enclosed than larger nests. 20The relative preference of groups of laying hens for two nest sizes-0.43 m 2 vs. 0.86 m 2 -was tested in a 21 free-access choice test. The experiment was conducted in two consecutive trials with 100 hens each. They 22 were housed from 18 to 36 weeks of age in five groups of 20 animals and had access to two commercial 23 group-nests differing in internal size only. We counted eggs daily as a measure of nest preference. At 28 24 and 36 weeks of age, videos were taken of the pens and inside the nests on one day during the first 5 25 hours of lights-on. The nest videos were used to record the number of hens per nest and their behaviour 26 2 Accepted to Applied Animal Behaviour Science, February 2014 with a 10 min scan sampling interval. The pen videos were observed continuously to count the total number 27 of nest visits per nest and to calculate the duration of nest visits of five focal hens per pen. 28We found a relative preference for the small nest as more eggs, fewer nest visits per egg and longer nest 29 visit durations were recorded for that nest. In addition, more hens-including more sitting hens-were in the 30 small nests during the main egg-laying period, while the number of standing hens did not differ. These 31 observations indicate that even though both nests may have been explored to a similar extent, the hens 32 preferred the small nest for egg-laying. 33 Keywords 34Laying hens, nest size, group-nests, nest choice, preference test, animal welfare 35 36 3

Nest choice in laying hens: Effects of nest partitions and social status

“…This reasoning could explain the lack of a difference in the number of visits per egg after the nest switch. Interestingly, unlike in other experiments (Ringgenberg et al, 2014a, Submitted for publication) there was no increase in the number of visits per egg over time although this may be because the current experiment did not look at this measure later than week 28 of age and/or more attractive nests were used.…”

“…In this experiment, the level of enclosure was likely higher in the partition nest, and as in our previous study (Ringgenberg et al, 2014a), hens preferred nests offering a greater degree of enclosure. However, although the proportion of eggs laid in the partition nest was significantly higher than 0.5, hens in all pens also laid eggs in the control nest.…”

“…Pre-laying behaviour and nest site selection are also affected by social factors, including the presence of hens (Riber, 2012), the identity of those hens (Ringgenberg et al, 2014a), and their relative social status (Freire et al, 1998). There are however conflicting results on whether social status affects nest site choice; i.e.…”

“…In response to the current industry trend of increasing the area of group-nests due to economic reasons, we compared two groupnests differing in size (0.43 m 2 vs. 0.86 m 2 ) in a previous study and found that hens laid more eggs and performed fewer nest visits per egg in the smaller nests (Ringgenberg et al, 2014a). When comparing the number of visits per egg per nest in a preference test, the nest with the fewest visits per egg is considered to be more attractive http://dx.doi.org/10.1016/j.applanim.2015.04.013 0168-1591/© 2015 Elsevier B.V. All rights reserved.…”

Welfare of organic laying hens kept at different indoor stocking densities in a multi-tier aviary system. I: egg laying, and use of veranda and outdoor area

“…In addition, in the present study the presence of rain puddles on the outdoor area gave the birds alternative access to water at times. Although hens prefer smaller nests (Ringgenberg et al, 2014), we have been unable to find published results on the influence of nest availability on total egg production in non-cage laying systems. Decreased access to nests lead to more floor eggs in ducks (Makagon and Mench, 2011), but we found only a slightly higher fraction of eggs laid outside the nests in the largest groups in one of the flocks, and nonnest eggs were included in the total count.…”