An experiment was conducted to evaluate the biometrics of organs (ovary, oviduct, liver, proventriculus and gizzard) of laying hens submitted to different forced-molting methods of molt and maintained at three different temperature. Organs were evaluated after molting and resting period. Six hundred birds were distributed according to a completely randomized experimental design in a 5×3 …
The objective of the present experiment was to compare the performance, egg quality and organ morphometrics of commercial layers submitted to alternative forced molting methods using dietary fibers. The experimental period included the phases of molting, rest, and second laying cycle (six periods of 28 days each). In the trial, 320 commercial Isa Brown layers …
The aim of this study was to compare the applicability of the non-feed removal method with the feed withdrawal method by using alfalfa meal and barley in molting. Moreover, the effects of humate (2 g/kg), carnitine (0.1 g/kg) and humate (2 g/kg) + carnitine (0.1 g/kg) supplementation to the diets during postmolt period along with …
This study was conducted to determine the ability of different molt diets to induce molt in 95-wk-old hens. The hens were randomly assigned to 4 treatments of 60 birds each: 1) molted by full feeding with broken rice (BROK), 2) corn (CRN), 3) cassava (CASS), or 4) nonmolted control (CONT) for 14 d. At 15 …
The neuroendocrine system controls animals’ adaptability to their environments by releasing psychotropic compounds such as catecholamines [epinephrine (EP), norepinephrine (NE), and dopamine (DA)], corticosterone (CORT), and serotonin (5-hydroxytryptamine or 5-HT). Changes of these neuroendocrine compounds have been used as biomarkers of animals’ stress responses associated with their well-being. Assuming that pullets, like laying hens, are …
Osteoporosis, a progressive decrease in mineralized structural bone, causes 20 to 35% of all mortalities in caged White Leghorn hens. Previous research has focused on manipulating the egg laying environment to improve skeletal health, with little research on the pullet. The objective of the current study was to determine the effect of perch access on …
The aim of this trial was to determine the influence of aerial perches on welfare and production parameters in free-range laying hens. Five commercial free-range houses, each containing between 7000 and 8000 birds, were used. Each house and range area was split in half to create two treatments. In half of the house the birds …
Provision of perches in cages could improve behaviour and physical conditions of layinghens. This study was conducted to investigate the choice of perch characteristics (shape, width, material and height) by caged hens under different group size, and to understand the choice by the perching behaviours of hens. This study was consisted of four trials: perch …
In a two-year experiment, we investigated the influence of sward plant species composition (sward type), stocking duration and state of sward degradation on the foraging behaviour of chickens. Laying hens (ISA Warren) were pastured on 15 sward types including 14 mono-cultures of grassland plant species (nine grasses and five forb species) and one mixed sward …
In small-group furnished cages with nests lined with artificial turf, a high use of nest and acceptable egg quality are generally achieved. However, artificial turf has drawbacks, such as not letting manure through and not being cleanable in position. Therefore, a more perforated nest-lining material would be preferable given that nest acceptance and egg quality …
Using laying hens, we investigated whether position of a nest box, both within the pen and relative to other nest boxes, influenced the preference for a nest box, and how a sudden and marked change to the preferred box influenced the use of nest boxes by the hens. Groups (n = 12) of 15 Isa …
The United Egg Producers husbandry guidelines for cages recommend a minimum of 432 to 555 cm² (67 to 86 in.²) of usable space/hen, defined as floor space that is of sufficient height for hens to stand upright. Because there is neither a quantitative value given for cage height nor an established method for calculating usable …
This study was conducted to evaluate the effects of cage density on laying hen performance, egg quality parameters, blood indices, and excreta mineral concentration. Eighty White Leghorns were housed at 4 cage densities of 2,000, 1,000, 667, and 500 cm² per hen, corresponding to 1, 2, 3, and 4 hens per cage. Throughout the study, …
National Nutritional Recommendations Outline
Studies on the prevalence of feather pecking in different commercial laying hen systems and its welfare and economic impacts are reviewed in the following paper. Current methods for controlling feather pecking include beak-trimming and alterations to light regimes, but these methods have significant disadvantages from the perspective of bird welfare. A substantial body of research …
Although the rearing period has an important influence on the development of feather pecking in laying hens, few studies have quantified the risk factors operating on commercial farms during this time and identified their long-term impact. Our aim was to conduct a longitudinal study to investigate the effect of rearing environment on feather pecking in …
Commercial laying hen chicks experience continuous light for up to 24 h/day in the first week of life. Under these conditions, active chicks disturb, and may direct feather pecks towards resting ones. Previous experimental work with small groups showed that both problems were reduced in chicks brooded by dark brooders (heaters). The current study aimed …