Changes in Serum Corticosterone Concentration of Laying Hens as a Response to Increased Population Density

Effects of stock density on the laying performance, blood parameter, corticosterone, litter quality, gas emission and bone mineral density of laying hens in floor pens

The effects of stocking density on the performance, egg quality, leukocyte concentration, blood biochemistry, corticosterone levels, bone mineral density, and noxious gas emission of laying hens were investigated. Eight hundred 34-week-old Hy-Line Brown laying hens (Gallus gallus domesticus) were randomly assigned to one of 4 treatments, each of which was replicated 4 times. Four stocking densi...

Phosphorus Partition in the Blood Serum of Laying Hens*

Much work has been done during recent years in investigating the calcium partition in the blood of laying hens. From this work an attempt has been made to determine the nature of the non-diffusible calcium. Although Laskowski (1) and Benjamin and Hess (2) investigated the partition of inorganic phosphorus in connection with the study of calcium in the serum of the laying hen, little has been do...

Effects of Isoflavones in Feed on Plasma Estradiol Concentration and Productive Performances in Laying Hens

Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans with structure similar to 17-β-estradiol and capable of binding to estrogen receptors (ERs).This experiment was conducted to demonstrate the effect of isoflavones on estradiol concentration in blood and its influence on the productive performances in ISA Brown laying hens fed with supplemented feed with large...

Feather Pecking of Laying Hens in Different Stocking Density and Type of Cage

Both stocking rate and housing systems are main factors influencing the occurrence of feather pecking in laying hens raised in conventional cage system. This study examines the effects of different type of cage and stock density on feather pecking behaviour in hens. Total of 216 Hisex Brown hens at 16 weeks of age were randomly selected and put into 2 types of battery cages: conventional cages ...

Response of laying hens to supplementation with various fatty acids when fed diets inadequate in protein and sulphur amino acids