Effect of cage tier and age on performance, egg quality and stress parameters of laying hens

Abstract

This study was conducted to investigate the effects of cage tier and age on performance characteristics of layer hybrids, egg quality and some stress parameters. Ninety laying hens (hybrid ATAK-S) of similar bodyweights were used in the experiment. They were housed in three-tier conventional battery cages (bottom, middle and top) with 600 cm 2 /per bird. The experiment was conducted on hens from the age of 18 weeks to 42 weeks. Layers at the age of 18 weeks were randomly allocated to conventional three-tier battery cages with five replicates of six hens per treatment in a completely randomized design. In the bottom, middle and top tiers, 5% age of yield was observed as 151, 146 and 156 days, respectively; 50% age of yield was 162.4, 158.6 and 161.8 days; 5% yield age bodyweight (BW) as 1597.8, 1460.5 and 1599.2 g; 50% yield age BW as 1708.7, 1666.4 and 1671.7 g, respectively. The effects of cage tiers on week 42 BW, feed conversion ratio (FCR), tonic immobility (TI), egg weight (EW), egg yield (EY), and most external and internal quality traits of the hens' eggs were found to be insignificant. Except for shape index (SI) and albumen pH, internal and external quality traits of eggs were significantly affected by age of the hens. In addition, there were significant effects of age on the FCR, EY, EW and oviposition time. The effects of cage tier on tonic immobility (TI) in week 42 and viability were found to be insignificant, but TI in week 30 was found to be significant. It can be concluded that cage tier did not have significant effects on egg yield, egg quality and indicators of stress parameters studied in the experiment. However, these parameters were affected by the age of the hens at the beginning of the laying period. ______________________________________________________________________________________

Impact of light-emitting diode and compact fluorescent light source type and cage tier on layers reared in an enriched cage system Part 1: Production performance and egg quality

“…In the present study, there was no difference for egg shape index of both light source types (P > 0.05). There were studies reporting that the cage tier did not affect the egg shape index [2,18,24,33,40]. However, in the present study, cage tier affected egg shape index (P < 0.05).…”

“…Thus, in the present study, the Haugh unit value was similar in both light type groups (P > 0.05). Karaman et al [33], Yıldız et al [44], and Şekeroğlu et al [24] reported that the Haugh unit value was also similar between the cage tiers of conventional battery cage system. In accordance with their results, we have found that the effect of cage tiers on the Haugh unit value was found to be similar (P > 0.05).…”

“…Moreover, Şekeroğlu et al [24] reported that there were no significant effects of cage tier on mortality of layers in three-tier conventional cage systems. In the present study, the mortality rate was found to be similar in different cage tiers (P > 0.05) which was lower compared to other studies [24]. There are several others reporting lower mortality rates in furnished cages when compared to the conventional cage systems [27,28] and in noncage systems [29,30].…”

“…However, they reported that cage tier did not affect egg production in enriched cages. On the other hand, several researchers reported that there was no difference between the cage tiers for egg production [21,24,33].…”

Impact of light-emitting diode and compact fluorescent lighting type and cage tier on layers reared in an enriched cage system, part 2: some welfare traits

“…The effect of lighting type and cage-tier interaction on TI duration and induction number was not significant at 45 weeks of age (P > 0.05). However, Şekeroğlu et al [33] T er reported that the shortest TI duration was found in low level cage tiers at 30 weeks of age. They also reported that there was no difference between the cage tiers regarding TI duration of layers at 45 weeks of age; however, TI duration was numerically lower at bottom cage tiers as aging progressed.…”