Effect of beak trimming on brown growing pullets and laying hens

1968 one-day old chicks of Isa brown hybrid were kept in an aviary system (Natura Typ AZ-187), which was divided in four groups of 492 animals each. At day 1, half of the animals were beak-trimmed by hot cut, whereas the beaks of the other chicks remained intact. At the beginning of week 16, 1500 pullets (375 animals per unit) were moved to a layer shed equipped with an aviary system of Rihs Boleg II-type, which was also divided in four units.<br>During the rearing period up to day 105, beak-trimming was followed only by minor effects on animal weight (- 2.5 %), weight uniformity (+ 4.4 %), food consumption (- 1.1 %) and mortality rate (1.2 vs. 1.6 %).<br>Due to beak-trimming at day 1, egg production was increased (+ 2.9 %) from week 21 to week 63, while food consumption and feed efficiency were lowered by 5.2 % and 7.4 %, respectively. Egg weight was hardly influenced by the beak treatment, but the percentage of normal eggs (53 – 65 g) was increased by 5.5 %. Mortality rate of the beak-trimmed hens was lowered by factor 5.6 (2.2 vs. 12.3 %), which was mainly due to a reduction of cannibalism-related mortality (0.3 vs. 7.5 %). Plumage condition of the non-beak-trimmed hens worsened drastically during the laying period, whereas beak-trimmed hens kept an acceptable feathering condition up to the end of the trial in week 63.<br>It can be concluded, that beak-trimming at day 1 is an effective tool in lowering feather pecking and cannibalism if understood as a palliative. Considering the effects on mortality and plumage condition, beak-trimming is also of great importance relating to the animal protection topic.