Feed form and perch design do not interact to production performance, gastrointestinal tract traits, behaviour and welfare of laying hens reared in enriched cages

1. It was hypothesised that perch material and design may affect utility and maintenance energy demand in laying hens, affecting their feed form preferences and daily feed consumption. Accordingly, perch design and feed form on hen performance, gastrointestinal tract functions and some behavioural and welfare-related traits were studied in laying hens (ATAK-S) reared in enriched colony cages from 24 to 40 weeks of age.2. The experiment was a 2 × 2 factorial investigating two perch materials and design (circular steel or mushroom-shaped plastic) and feed form (mash or crumble). A total of 396 hens were randomly assigned to one of the four treatment groups with nine replicates each (11 birds per replicate).3. Except for feeding behaviour and prevalence of foot pad dermatitis at 40 weeks of age, the modification of the perch design did not have a significant effect on the traits examined. Mushroom-shaped plastic perches reduced feeding behaviour (p < 0.01) and the incidence of foot pad dermatitis at 40 weeks of age (p < 0.001).4. Performance traits were not affected by feed form. Intake, final body weight and FCR for crumble-fed laying hens were greater than those fed mash (p < 0.01).5. Hens fed mash had higher (p < 0.01) relative gizzard weights along with lower (p < 0.05) pH values, pancreatic chymotrypsin, amylase and lipase activities (p < 0.05), and duodenal absorption surface areas (p < 0.01). Ultimately, this gave higher protein digestibility (p < 0.05) compared to those receiving crumble.6. In conclusion, in enriched cage rearing systems, mashed feed was preferred over crumble to efficiently maintain productive performance. Compared to circular steel, plastic mushroom-shaped perches were associated with better footpad health and welfare.

The Effect of Housing Environment on Commercial Brown Egg Layer Production, USDA Grade and USDA Size Distribution

Consumer demand for retail cage-free eggs is driving the layer industry towards greater use of extensive housing environments. However, there is limited research on how these environments affect egg production characteristics of brown egg layers, as was the focus of this study. Five housing environments were evaluated under typical industry conditions, including conventional cages, enrichable colony cages, enriched colony cages, cage-free and free-range. Three different brown egg laying strains were housed in the different housing environments and managed according to standard husbandry practices and stocking densities. Data collection for the strains began at 17 weeks of age, with a base period of 28 days for feed weigh backs and egg quality assessments. Housing environment had a highly significant (p < 0.0001) effect on all egg production characteristics measured, including egg production rates (% hen-day and % hen-housed), feed consumption (g/bird/day), feed conversion (egg g/feed g), and mortality rate (%) as well as percent grade A, B, and loss. Previous research revealed better egg production metrics for white egg layers in caged environments than extensive environments. In contrast, we observed brown egg layers had optimum production results for the free-range housing environments, and the poorest performance in enrichable colony cages.

Effects of Different-Sized Cages on the Production Performance, Serum Parameters, and Caecal Microbiota Composition of Laying Hens

The effects of four different-sized cages—huge (HC), large (LC), medium (MC), and small (SC) cages—on the productive performance, serum biochemical indices, and caecal microbiota composition of Roman laying hens were investigated. At 44 weeks of age, a total of 450 hens were selected and allocated to the four groups, with six replicates each. Equal stocking density (0.054 m2 per bird) was maintained among the four groups throughout the experiment, and number of birds/cage changed for each treatment. After 2 weeks of preliminary trial, the formal experiment was performed from 46 to 60 weeks of age. The laying rate and feed conversion ratio (FCR) were determined daily, antibody titres were measured every 3 weeks, and serum biochemical parameters and caecal microbiota composition were analysed at 60 weeks of age. Compared to HC and SC, the higher laying rate and lower FCR in MC and LC indicated positive effects on egg production and feed efficiency, while SC showed the highest body weight gain (p < 0.05). With increasing cage size, the serum triglycerides (TG) and total cholesterol (T-CH) levels were reduced, and serum glutathione peroxidase (GSH-Px) activity improved, where birds raised in HCs had the lowest serum TG and T-CH and the highest GSH-Px activity. Twenty-nine different phyla and 301 different genera were detected in the caecal microbiota of birds in the four groups. Methanobrevibacter was significantly higher in the SC than in the other groups (p < 0.05). Faecalibacterium was most abundant in the MC compared with the other groups (p < 0.05) and was significantly positively correlated with serum GSH-Px concentration (R = 0.214, p = 0.0017). Lactobacillus was significantly less abundant in the LC and MC than in the HC and SC groups (p < 0.05) and was significantly positively correlated with body weight (R = 0.350, p = 0.0009) but negatively correlated with laying rate and FCR. In conclusion, MC were superior to HC and LC in improving feed conversion efficiency and caecal microflora composition compared to the SC. An appropriate increase in cage size is beneficial to laying hen production and health.

Effects of the genotype, cage type and time period on the behaviour of laying hybrids at the same egg production level

Hybrids with different morphological and yield characteristics are used in the table egg production. There is no change in the cage systems according to the different hybrids in the regulation. This study aimed to investigate the effects of genotype (brown laying hybrids (BLH) and white laying hybrids (WLH)) and cage type (conventional and enriched cages) on behaviours of hens at the 90% egg production level. Behavioural data were recorded with video cameras during the 4 days. Data were analysed in 6 time periods as 05.00-08.00 am, 09.00-12.00 am, 01.00-04.00 pm, 05.00-08.00 pm, 09.00-12.00 pm and 01.00-04.00 am. Behaviour inspection each hour was divided into 4 quarters and the first 3 min of each quarter were evaluated. Behaviours were represented as the proportion of the total behaviour performed in the time period by a given hen. There was no interaction between hens' behaviour and the genotype at the same egg production level. The frequency of feeding behaviour was found to be significantly lower (P < 0.01), but comfort behaviour was higher (P < 0.05) in hens that were reared in the enriched cages. Only preening was seen as a comfort behaviour due to the cage size. The feeding, drinking, pecking hen, comforting, walking, sitting, resting and perching behaviours changed during the day (P < 0.01). Especially, the transition from light to dark influenced the perching behaviour negatively. No interactions were detected amongst genotype, cage type and time period. Feeding behaviour decreased and the comfort behaviour increased in the hens that were reared in the enriched cages because there were materials that would exhibit different behaviours. Hens in the enriched cage could not suddenly adapt to the dark and light period. For this reason, transitions to light and dark periods in poultry houses should be provided gradually, as in natural life.

Effects of Different Scratch Mat Designs on Hen Behaviour and Eggs Laid in Enriched Cages

Simple Summary

Enriched cages for laying hens must contain litter so that pecking and scratching are possible. This is typically provided using layer’s feed dispensed onto a scratch mat, however, there are no regulations on the size or materials of the mat. This study examined how different scratch mat designs and bird age affected behaviours on the mat at three times of day, and their influence on where eggs were laid and shell quality. The proportion of hens at the scratch mats did not increase during or shortly after the application of scratch feed, however, they were more likely to be foraging then. Most eggs collected were clean and laid in the nest. Of the small proportion of eggs that were cracked or dirty, the mat type did not affect dirty eggs, but eggs laid opposite the Big Dutchman mats were more likely to be cracked at 79 weeks of age than at any other mat type or age. There appeared to be no optimal scratch mat design (of those studied) and their use (during observations) was low, suggesting that mat designs were not major influencers on bird behaviour.

Abstract

Laying hens in the UK and EU must be provided with litter for pecking and scratching. In enriched cages, this is commonly provided by dispensing layer’s feed onto a scratch mat. Mats vary in design and size, which might affect hen behaviour and egg quality, since eggs are sometimes laid at the mats. We investigated if four different scratch mats (BD, K, V, Z) provided to hens in enriched cages resulted in differences in behaviour on the mats and external egg quality. Twenty-four 60-bird cages (6 cages/bank × 4 banks) with 2 mats/cage at one tier of a commercial enriched cage unit were used. Mats were allocated to cages in a balanced design prior to the flock arriving. Hens and eggs were studied at 30, 50 and 79 weeks of age, with three behaviour observations (before, during or after scratch feed application). The data were analysed by GLMMs or LMMs. The vast proportions of birds on the mats were standing (0.720) or sitting (0.250). Bird proportions on the mats were low overall and declined from 0.028 (30 weeks) and 0.030 (50 weeks) to 0.020 (79 weeks) (p < 0.001). The greatest proportion of hens were observed on Z (p < 0.001), which had the largest area, but relative to the available area least birds were on Z and most were on K (p < 0.001). Foraging was not affected by bird age or mat type but was greater at the second observation (p < 0.001). Most eggs were laid in the nest box and were clean. Clean eggs declined, and dirty eggs increased, significantly with age, particularly at the scratch mat (p < 0.001). Dirty eggs were not affected by mat design. Cracked eggs were highest at 79 weeks of age, particularly with BD mats (p < 0.001). Overall, scratch mat designs had minimal effects on behaviour (but few hens were seen there) and egg quality.

Effects of cage type on performance, welfare, and microbiological properties of laying hens during the molting period and the second production cycle

As most of the unenriched cages will soon switch to enriched cages, it is important to characterize all the effects in the laying hens for sustainable production. Laying hens can be used in several production periods by applying molting. The aim of this study was to determine the cage type (unenriched and enriched) on performance, welfare, and microbiological properties of laying hens during the molting period and the second production cycle. Overall, 840 brown laying hybrids were used in the experiment. Laying hens were reared on two different cage types (unenriched cage (UEC) and enriched cage (EC)) in the same poultry house. When the hybrids were 75 weeks old, they were subjected to force molting with whole grain barley. Performance, welfare, microbiological, and serological data of laying hens were obtained from 73 to 107 weeks of age. Egg production, egg weight, feed conversion ratio, breaking strength, albumen and yolk index, Haugh unit, feather condition, and breaking force of femur and metatarsus were better in the post-molting period. However, keel bone deformities and Newcastle disease virus antibody titers are the worst in the post-molting period. Stiffness of femur and metatarsus was increased with period. These results indicate that necessary precautions should be taken against the problems that may occur in the direction of bone and health. During the molting period, hens kept in EC had lower egg production but they returned to egg production at a high rate. EC type had a positive effect on egg production, feed conversion ratio, feather and foot condition, and breaking force of metatarsus.

The effect of an enriched laying environment on welfare, performance, and egg quality parameters of laying hens kept in a cage system

The aim of this study was to evaluate the welfare and performance of laying hens kept in a furnished cage system equipped with additional feeders. A total of 72 Lohmann Brown hens were randomly assigned to 4 experimental groups. Each group consisted of 6 cages housing 3 birds per cage (18 birds per group). Group I was a control group without an extra feeder in the cages. Experimental groups GII, GIII, and GIV contained one, 2, and 3 additional feeders in the cages, respectively. The assessment of bird welfare was based on production, physiological and behavioral parameters, as well as on the basis of external appearance. The experiment lasted 12 wk. The obtained results suggest that enriching laying hens' cages with additional feeders improved the welfare of the hens. Enrichment of cages significantly reduced the number of feather pecking and aggressive behaviors in the GII and GIV groups (P < 0.01) and the GIII group (P < 0.05). Breast plumage was significantly (P < 0.05) better in the GII group compared with that in the control group. The control group also had the worst general plumage (P < 0.01). The GII and GIV groups were also characterized by significantly (P < 0.05) lower blood corticosterone concentrations compared with the control group. No negative changes in egg production and quality parameters were observed in the experimental groups. Only eggs from the GIV group had significantly (P < 0.05) lower breaking strength than those from the control and GII group. The results suggest that the best solution is to place 1 additional feeder in furnished laying hens' cages.

The Effect of the Type of Alternative Housing System, Genotype and Age of Laying Hens on Egg Quality

The present study investigated the effect of the type of alternative housing system, and genotype and age of laying hens on physical traits of egg shell and contents. It was demonstrated that alternative housing system type influenced egg weight and shape, and eggshell color and yolk color intensity. Eggs from free-range system were heavier and were characterized by more intense yolk color. No effect of alternative housing system type on albumen height, value of Haugh units (HU value) and presence of meat and blood spots was noted. Hen genotype had a significant effect on egg weight and eggshell color intensity in each of the alternative housing systems tested in this study. Hy-line Brown hens laid heavier eggs than hens of native breeds. Genotype was also observed to affect egg content traits (albumen height, HU values and presence of meat and blood spots). Independently of the type of alternative housing system, most blood and meat spots were noted in eggs of hens laying brown-shelled eggs, i.e. R-11 and Hy-line Brown layers. Laying hen age significantly impacted on egg weight, yolk percentage, eggshell traits (color intensity, weight, thickness and strength) and egg content traits (HU value, yolk weight and color intensity, presence of meat and blood spots). Older hens laid heavier eggs with a greater yolk percentage but with thinner eggshell.

Egg production and welfare of laying hens kept in different housing systems (conventional, enriched cage, and free range)

The aim of this study was to compare egg production performance and welfare traits of laying hens kept in conventional cage (CC), enriched cage (EC), and free range (FR). Lohmann Brown laying hens (n = 480 with 160 per housing type) were studied across a production cycle from placement at 17 wk until depopulation at 66 wk. The hens were randomly allocated into cages or pens of housing system groups; within each system there were four replicates with 40 hens in each pen or cage. The hen day egg production (P = 0.037), feed intake (FI) (P < 0.001), egg mass (EM) (P < 0.001), and dirty egg ratio of hens were higher in the FR system but similar in the CC and EC systems. The highest mortality ratio was found in EC system hens (P = 0.020). The best feather score was found in FR system hens (P < 0.001). The worse body wound score was found in EC system hens (P = 0.038). On the other hand, the worse bumble foot and footpad lesions were found in FR system hens (P < 0.001). The highest tibia breaking strength was found in FR system hens compared with in CC and EC system hens (P < 0.001). The highest Heterophil/Lymphocyte ( H/L: ) ratio was found in CC system hens (P = 0.006) but the blood phosphorus ( P: ) level was higher in FR system hens (P = 0.013). The tonic immobility, blood glucose, total cholesterol, triglyceride, and Ca values of hens were found to be similar in all systems (P > 0.05). The hens in the FR system had additional space for optimum comfort and better feather and bone traits, but the dirty egg ratio, feed consumption, and foot lesions were higher than in CC and EC systems.