Hy-Line W-36, W-98, and Brown hens lay approximately the same number of eggs/hen housed to 80 wk; however, little is known about differences in performance during heat stress (HS). Two experiments were performed. The first experiment evaluated intestinal calcium uptake (CaT), heat shock protein-70 (HSP70) liver expression, and endocrine status in the 3 strains under …
Two experiments of 4 × 2 × 2 factorial arrangements of 4 dietary energy levels, 2 molting methods (feed withdrawal …
To approximate a commercially induced molt, feed was withdrawn (FW) from Hy-Line W-36 hens (65-wk-old) until they lost 35% of their initial body weight. Behaviors of 36 FW hens and 36 control hens were videorecorded on Days 1 to 3, 8 to 10, and 19 to 21 of FW, when FW hens reached 15, 25, …
Feed deprivation has been adopted by the commercial egg industry to induce molt because it is the easiest method to apply and produces the best results. Feed deprivation, however, raises concerns about animal welfare. Birds respond to long-term feed deprivation in three phases. The first phase lasts at most a few days, during which physiological …
The behavioral responses of laying hens to a 4-day fast were investigated. Three hundred and sixty Hyline W77 (W77) and 360 Hyline Brown (Brown) lPweek-old pullets were housed as pairs in cages in separate rooms for each stock. At 63 weeks of age, feed was withdrawn for 96 h from half of the W77 hens. …
1. The applicability of different ratios of bitter vetch seed as a new method for moult induction in laying hens …
Induced molting in egg-laying hens is an important method for maximizing hen egg production and quality as well as hen health in commercial settings; however, there is growing societal concern over its effects on hen well-being. Using individual hens as their own controls, this research examined the behavior of hens subjected to different treatments of …
In the commercial egg industry the management practice of using feed withdrawal to induce a flock to molt has been …
A study was conducted to evaluate skeletal quality and eggshell parameters of molted hens at the end of the second …
We experimented to evaluate the effect of a number of molting techniques that appeared to be less stressful than the conventional feed withdrawal (FW) method on postmolt performance. The molting techniques involved a continuous FW (T1, control group), 1 d FW followed by feeding a grape pomace (GP) diet containing 10 ppm thyroxine (T2) ad …
An experiment was conducted to determine the effects of hen BW before molt and the percentage of BW loss during molt on the subsequent performance and profitability of hens during the second cycle of production. Results revealed that profits associated with Light hens (≤1,453g, or 3.2 lb) were from 1.8¢ to 3.8¢/dozen eggs higher than …
Several dietary alternatives to feed withdrawal have been proposed to induce a molt in laying hens. This study compared the behavior of laying hens on an alfalfa crumble diet (ALC) to hens that were either in a conventional layer diet (FF) or hens that had feed withdrawn (FW) during a 9-d trial. Each treatment consisted …
An experiment was conducted using 336 White Leghorn hens (60 wk of age) randomly assigned to one of four treatments that consisted of feed removal for 4 or 10 d or no feed removal with ad libitum access to 95% corn or 95% wheat middlings molt diets that contained supplemental minerals and vitamins. At the …
Induced molting is a management practice used primarily by commercial egg producers to optimize the utilization of their layer flocks. Historically, flocks produced eggs for a laying cycle of 1 yr duration and then were sold. With induced molting, flocks are molted and returned to lay for additional laying periods, thereby spreading fixed costs over …
Two commercial strains, Hy-Line W-36 and DeKalb XL, were moved to a laying house at 18 wk of age. They were housed 6 hens/layer cage at 2 densities (361 and 482 cm2/bird) with 2 replications each per strain/density combination. The high-density treatment contained 24 hens/replication and the low-density treatment contained 18 hens/replication for a total …
This experiment was conducted to determine the effects of cage location and tier level with respect to light intensity on …
During the past decade research work has indicated that ahemeral cycles could markedly influence egg production, shell quality and egg …
Light patterns have less effect on numbers of eggs laid by current stocks than on those of forty years ago, …