Spatial distribution of cannibalism mortalities in commercial laying hens

Abstract

The distribution of cannibalism cases in a flock of 19,776 Babcock White Leghorns was monitored from 21 to 54 wk of age. The hens were kept in a single-floor house consisting of four banks of two-deck stair-step cages. Each of the 4,944 cages held four hens at a density of 152 cm(2) (60 inches(2)) per hen. Each cage was assigned a number from 1 to 4,944, and each dead bird was tagged according to its cage of origin. Dead birds were collected daily, kept in a freezer, and necropsied weekly. Farm personnel routinely transferred a live hen from an end cage to a cage where a mortality had occurred. The cause of death, age, cage number, and cage location were recorded for each dead hen. Of the 1,173 hens that died during the study period, 253 (21.6%) died from egg peritonitis, 184 (15.7%) from hypocalcemia, 167 (14.1%) from cannibalism, 164 (14%) from neoplastic disease, and the rest from various other causes. Cannibalism cases were analyzed statistically for clustering. Cannibalism was defined as death from tissue trauma and hemorrhage inflicted by cage mates. A spatial analysis showed that cannibalism is not a random event but one that occurs in clusters. The incidence of cannibalism was also found to be significantly higher on the top rows of cages as compared with the bottom rows.

Gut-Brain Axis: Probiotic,Bacillus subtilis, Prevents Aggression via the Modification of the Central Serotonergic System

“…However, in artificial production environments, such as in the poultry industry, aggression causes increased social stress and feather and body damage, in some instances these injuries leading ultimately to cannibalism. Cannibalism is a major concern related to non-beak trimmed bird deaths in current housing environments [259,260]. Beak trimming (BT) is a routine procedure practiced in the US egg industry for reducing social stress by preventing and/or inhibiting feather pecking and cannibalism.…”

Some aspects of chicken behavior and welfare

“…Rooijen (2010) observed that some commercial layer strains still carry the wild genotype that has this behavior; however, environmental stimuli are required for its expression. Tablant et al (2000) evaluated the incidence of cannibalism and its relationship with mortality in a commercial layer farm, and observed that it was the third cause of mortality in Babcock White Leghorns between 21 and 54 weeks of age reared in cages at a stocking density of 150 cm 2 .Most lesions were observed in the cloaca after the peak of egg production. Other major mortality causes were peritonitis, neoplasias, and hypocalcemia.…”

The Relationships between Damaging Behaviours and Health in Laying Hens

“…Cannibalistic behaviour involves beak-inflicted damage followed by the consumption of blood and tissues of conspecifics while they are still alive or after death [51]. Cannibalistic behaviour is learned by individual birds and can spread to others through social learning [51], even through adjacent cages [52]. Severe feather pecking can lead to increased risks of cannibalism [53].…”