the aim of this study was to develop a quantitative radiographic method for assessment of experimentalosteoporosis in leghorn breed laying hens. three groups of 24 leghorn pullets were reared in cage and fed aration containing different calcium levels, including 3.55, 2.075 and 0.6 percent (for groups 1-3, respectively). the hens were fed this diet from 17 weeks of age to the end of the experim...

New housing systems for commercial egg production, furnished cages and non-cage systems, should improve the welfare of laying hens. In particular, thanks to the presence of a litter area, these new housing systems are thought to satisfy the dust-bathing motivation of hens more than in conventional cages, in which no litter area is present. However, although apparently obvious, there is no concr...

In this paper, vocalizations of laying hens (Hyline Brown) were focused. An experiment was designed to obtain acoustic features of laying hens with different ages: 35days-old, 95days-old and 125days-old. Vocalizations were recorded by the microphone MPA201. Analysis was done by some analytical software in order to gain time-domain features and frequency-domain properties of laying hens’ sound. ...

The changes in egg production, in broodiness index and in plasma concentrations of LH, prolactin, oestradiol and progesterone were monitored throughout the first period of laying in turkey hens. The hens were subsequently classified according to their ability to express broodiness (33%) and their laying persistency; 25% were out-of-lay by the end of the experiment. A high percentage (67%) of th...

Fatty liver is a common energy metabolic disorder in caged laying hens. Considering that the egg industry is shifting from conventional cages to alternative housing systems such as enriched cages, the objective of this study was to determine the effects of perches on fat deposition and liver health in laying hens. Three hundred twenty-four 17-wk-old White Leghorn hens were housed in 1 of 4 trea...

Very-low-density (VLD) lipoproteins and portomicrons were isolated from the plasma of immature and laying hens and their size, lipid composition and susceptibility to hydrolysis by lipoprotein lipase were compared. In agreement with other studies, VLD lipoproteins from laying hens were found to be smaller and have a different lipid composition than VLD lipoproteins from immature hens. Portomicr...

Turkey hens can rapidly shift from a laying condition to one characterized by ovarian regression, incubation behavior, and hyperprolactinemia. Although remarkable changes occur in hormonal profiles as turkey hens pass from a laying to an incubating state, studies have not been undertaken to examine histochemical alterations of functionally relevant pituicytes in the adenohypophysis. The objecti...

Objective: The experiment was conducted to evaluate the effect of different levels of germinated barley on performance and egg quality in laying hen. Methods: One hundred and twenty laying hens, 44-weeks old, Lohmann LSL hens were used in this experiment. Birds were assigned randomly to the groups, each of which consisted of 20 birds (4 replicate cages each containing 5 birds). The experiment w...

Heat stress in laying hens is prompted by combinations of environmental temperature and humidity that prevent the bird’s thermoregulatory process from effectively dissipating the heat produced during metabolism [32]. High environmental temperature is the major problem faced by laying hens as well as poultry farmers usually in summer months. The ideal temperature for laying hens is about 20°C [2...

This study aimed to investigate the responses to abrupt changes in feeding and illumination during the egglaying period. Six hens were housed individually in cages under constant environmental conditions, with a photoperiod of 15 h (0400-1900) and ad libitum access to food for 10 days. Then the same hens were subjected to a feed withdrawal trial (between 1200 and 0830), followed by a 5-h reduct...