Haipeng Shi

Caged laying hens are prone to calcium deficiencies, resulting in osteoporosis and egg quality deterioration during the later phase of the laying cycle. Fluorescent light and light-emitting diodes (LEDs), which are widely used in poultry houses now, are both deficient in ultraviolet (UV) light, the lack of which is detrimental to chickens’ welfare and health. This study was conducted to investigate the effects of UVB light supplementation using LEDs on the bone traits, blood parameters, laying performance, and egg quality for caged laying hens at 68–75 weeks. In total, 120 Jingfen laying hens were randomly assigned to four different groups, with three replicates in each group (10 hens in each cage as a replicate). UVB-LED lamps installed under the feed troughs were used to provide UVB light (296–316 nm) for the birds in the three treatment groups (1 h, 2 h, and 3 h UVB supplementation per day, respectively), while the control group was not exposed to UVB-LED light. Bone traits, egg quality, and amounts of calcium (Ca), phosphorus (P), 25-hydroxyvitamin D₃ (25(OH)D₃), 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃), and 7-dehydrocholesterol (7-DHC) in both the serum and egg yolks were tested during the experiment. The results demonstrated that UVB-LED exposure significantly increased the bone mineral density (BMD), egg production, and yolk 1,25(OH)₂D₃ concentrations (p < 0.05), and reduced the content of serum 7-DHC (p < 0.05), especially in the 2 h/day group; however, it did not improve egg quality, vitamin D metabolites, or photoproducts in the serum and yolk 25(OH)₂D₃ concentrations (p > 0.05). This study concluded that UVB supplementation using LEDs had a positive effect on caged laying hens during the later phase of the laying cycle.

Natural mating colony cages for layer breeders have become commonplace for layer breeders in China. However, feather pecking (FP) and cannibalism are prominent in this system. The objective of this study was to investigate the effects of four light-emitting diode (LED) light colors (white: WL, red: RL, yellow-orange: YO, blue-green: BG) with two light intensities for each color, on FP, plumage condition, cannibalism, fear, and stress. A total of 32 identical cages were used for the eight treatments (four replicates for each treatment). For both light intensities, hens in RL had a lowest frequency of severe FP, whereas hens in WL had the highest frequency of severe FP. Hens in RL and BG had better plumage conditions than in WL and YO. Compared with RL and BG treatments, hens treated with WL and YO had a significantly longer tonic immobility (TI) duration. Hens treated with RL had a higher concentration of 5-hydroxytryptamine (5-HT), a lower concentration of corticosterone (CORT), and a lower heterophil to lymphocyte ratio than WL and YO. Furthermore, RL could significantly reduce mortality from cannibalism. Overall, hens treated with RL and low light intensity showed a lower frequency of severe FP, less damaged plumage, were less fearful, had lower physiological indicators of stress, and had reduced mortality from cannibalism. Transforming the light color to red or dimming the light could be regarded as an effective method to reduce the risk of FP and alleviate the fear responses of layer breeders.

Colony cages for natural mating have been applied on many layer breeder farms. However, feather pecking and cloacal cannibalism are considered as prominent problems for these systems. This study aimed to investigate the effects on feather pecking and vent pecking behaviors by providing layer breeders with nest boxes (0.90 m L × 0.40 m W × 0.60 m H) in colony cages for natural mating (4.80 m L × 1.20 m W × 0.71 m H). Video recording and artificial observation were adopted. The results showed that the usage of nest boxes gradually increased from the beginning of nest boxes providing at the age of 37 weeks to the end of the experiment at the age of 55 weeks. The utilization rates of nest boxes were 36.75%, 44.75% and 50.38% at the ages of 41 weeks, 47 weeks and 53 weeks, respectively. The hens in the cages without nest boxes showed significantly more frequent gentle feather pecks (both given and received) than hens in the cages with nest boxes at the ages of 41 weeks, 47 weeks and 53 weeks. A decreasing trend of gentle feather pecking frequency (both given and received) was found with the increasing age for both the two groups. No significant difference was found in the number of given or received severe feather pecks at the age of 41 weeks. The hens in the cages without nest boxes showed a significantly higher frequency of given and received severe feather pecks than hens in the cages with nest boxes at the ages of 47 weeks and 53 weeks (p<0.05). Both cannibalistic injury occurrence and mortality rate in the cages with nest boxes were significantly lower than those in the cages without nest boxes. In conclusion, providing nest boxes in colony cages for natural mating could decrease abnormal pecking behaviors and improve animal welfare conditions of layer breeders. Keywords: feather pecking, vent pecking, nest box, colony cage, cloacal cannibalism, layer breeder, animal welfare DOI: 10.25165/j.ijabe.20181106.3323 Citation: Shi H P, Zheng W C, Tu J, Li B M. Reducing feather pecking and cloacal cannibalism by providing layer breeders with nest boxes in colony cages for natural mating. Int J Agric & Biol Eng, 2018; 11(6): 27–32.

Pullets often raised in cage system from week 1 to week 13 in China, when transferred to aviary system after, there will be a problem with adapt. A large cage aviary unit (LCAU) system was developed, which allocated with facilities such as ramps to help cage reared hens to adapt to the multi-tier space. To investigate hens’ adaptability to the new system, space use over time in the LCAU system during the first 10 days after hens transferred were recorded, instantaneous scan sampling and continuous focal sampling were used to assess the behavior difference of hens between the LCAU and conventional cage (CC) systems. On the first day of arrival, 10.03% of hens reached the second tier (S2) and the third tier (S3) of the aviary. During the observation period, an average of 2.42% of hens climbed and stayed at the upper tiers every day. Space allowance on floor of the first tier (S1) increased from 444.62 cm2/hen (91 d) to 586.32 cm2/hen (100 d), which was more than 540 cm2/hen in the CC system. Comfort behaviors in the LCAU system were significantly more than in the CC system (p0.05) on the last 5 days of the whole observing period. The results indicated that hens gradually learned to use the 3-dimensional space in the initial settling-in period and, gained a good welfare condition in LCAU system. Further studies are needed to investigate the three-dimensional preferences and behavior expression in difference period to bridge the gap in knowledge of space use capacity among adult laying hens. Keywords: large cage aviary unit, laying hen, welfare, comfort behaviors, adaptability DOI: 10.25165/j.ijabe.20181105.3216 Citation: Yang L, Tong Q, Shi H P, Chen G, Shi Z X, Zheng W C, et al. Adaptability of pullets from cages to a large cage aviary unit system during the initial settling-in period. Int J Agric & Biol Eng, 2018; 11(5): 70–76.