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...

In this experiment 240 Hy-Line (W-36) laying hens from 65 to 75 weeks distributed in 5 treatments and 4 replicates (12 birds per replicate) in a completely randomized design were used. The amounts of watermelon skin meal (WSM) used to set the treatments were 0, 0.5, 1, 1.5 and 2% in 1 to 5 experimental groups. The results showed that using WSM up to 2% significantly improved the performance and...

1. The aim was to test whether provision of foraging material and food form influence feather pecking and feather damage in laying hens. 2. From week 19 of age, 16 groups of 11 hens (white Lohman Selected Leghorn hybrids) were kept in pens with or without access to long-cut straw as foraging material and fed on either mash or pellets. 3. Foraging behaviour was increased in hens with access to s...

background: old laying hens are more prone to dietary calcium (ca) and phosphorus (p) deficiencies as  they absorb ca and p less efficiently than younger hens. objectives: in a 2×2 factorial design, the influence of diets with two levels of available phosphorus (ap) and phytase enzyme on the laying performance, egg quality and tibia bone characteristics of laying hens at their late 2nd producti...

this experiment was designed to evaluate the effects of different levels of tomato pomace (dtp) with different multi enzymes on the performance and egg quality of laying hens at the first phase of production. in this experiment 432 hens were used in a completely randomized design in a factorial arrangement of 4×4, with four levels of tomato pomace (0, 4, 8 and 12) and different enzymes (without...

in this experiment 144 hy-line (w36) laying hens, 65 to 77 weeks of age were separated into 4 treatments with 3 replicates (12 birds per replicate) in a completely randomized design experiment. the grass clipping wastes incorporated into a complete formulated layer diet, consisting on a corn and soybean based diet, were 0, 1.5, 3.0 and 4.5% in 1 to 4 experimental groups. the results showed that...

Domestic chickens are an established model organism for studies on learning and memory. Commonly, the chicks are used as subjects in several different learning tests, including one trial learning tests. However, for adult laying hens no such one trial learning tests have been established. In particular, there is no test established which focuses on the role of the hippocampus, a brain region, w...

The present study was undertaken to compare the changes in circulating levels of inhibin-B, prolactin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol-17beta, progesterone and testosterone during the different reproductive states of turkey hens. Blood samples were collected during different reproductive states, at laying, incubating and out of lay. Inhibin-B was measured...

A trial was conducted to study the effect of two dietary electrolyte balances (dEB, dEB=Na+K-Cl, meq/100g) on the productive performance, quality of eggs and physiological status of Hy-Line Brown laying hens. 128 hens were allocated in cages (4 hens/cage) and divided into two experimental groups (16 repetitions/group). The diets were isoproteic and isocaloric with different electrolyte balance ...

Laying hens may face a number of welfare problems including: acute and chronic pain caused by beak trimming; exaggerated fearfulness that may cause stress and suffocation; difficulties in locating resources, resulting potentially in emaciation and dehydration; frustration and boredom, caused by an environment that is barren; feather pecking; cannibalism; foot lesions; and bone fractures. In Eur...