Broken and weak bones of laying hens are major welfare concerns in the table egg industry. Bone quality at the end of lay of brown- (Shaver 579) and white-(Shaver 2000) egg strains were compared. Prior to the start of the experiment, the hens had been housed in laying hen cages (2/cage). At 423 d of age (60 wk + 3 d), 24 hens of each strain were selected and individually caged, and egg producti...

Despite considerable research on hormone-mediated maternal effects in birds, the underlying physiology remains poorly understood. This study investigated a potential regulation mechanism for differential accumulation of gonadal hormones in bird eggs. Across vertebrates, glucocorticoids can suppress reproduction by downregulating gonadal hormones. Using the chicken as a model species, we therefo...

An experiment was conducted to investigate the effects of dietary supplementation of copper chelates in the form of methionine, chitosan and yeast on the performance of laying hens. Four hundred ISA Brown layers, 84 wks old, were assigned to 4 treatments: control, 100 ppm Cu in methionine chelate (Met-Cu), 100 ppm Cu as chitosan chelate (Chitosan-Cu) and 100 ppm Cu as yeast chelate (Yeast-Cu). ...

Abstract Background The study examined the effects of dietary supplementation Syzygium aromaticum leaf meal (SLM) on haematology, serum biochemistry and antioxidative status laying hens. Results A total 150 20-week-old Isa brown birds were randomly assigned to three experimental diets: Diet 1/control (no supplementation), 2 (0.25% SLM) 3 (0.50% SLM). Each diet was further divided into five (5) ...

The maintenance of bone strength has been an important issue in the debate over cage use for laying hens. Bone strength depends on adequate mechanical load and cages restrict movement. Four laying crosses (Lohmann White, Lohmann Brown, H&N White, and Rhode Island Red × Barred Plymouth Rock cross hens) were housed in conventional cages or in floor pens equipped with perches and nest boxes to mea...

The development of a monitoring system to identify the presence of laying hens, in a closed room of a free-range commercial organic egg production farm, was the aim of this study. This monitoring system was based on the infrared (IR) technology and had, as final target, a possible reduction of atmospheric ammonia levels and bacterial load. Tests were carried out for three weeks and involved 7 I...

1. Laying hens, 225 white and 225 brown, were fed for 90 d to compare a control diet with diets containing 70, 140, 210 and 280 g/kg chia (Salvia hispanica L.) seed. 2. Hen weight was not significantly affected by diet; however, manure production was less for the hens fed on chia. 3. Egg weight and production, yolk weight, and yolk percentage were determined at d 0, 30, 43, 58, 72 and 90. 4. A ...

Tonic immobility reaction and heterophil:lymphocyte ratio were studied in hens laying pink eggs from three brown egg Spanish breeds (Barred Red Vasca, Red Vasca, Red Villafranquina). There was no significant difference among breeds in terms of tonic immobility duration or heterophil:lymphocyte ratio. Tonic immobility duration was significantly shorter in the pink (220 + or - 23 s) than in the n...

Commercial laying hens are prone to injurious pecking (IP), a common multifactorial problem. A 2 × 2 × 2 factorial design assessed the effects of breed (Lohmann Brown Classic (L) or Hyline Brown (H)), beak treatment (infra-red treated (T) or not (NT)), and environment (extra enrichment (EE) or no extra enrichment (NE)) on mortality, behaviour, feather cover, and beak shape. Hens were allocated ...