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...

this experiment was carried out to study the effect of sodium chloride from drinking water and feed intake on the quality of egs from laying hens. four hundred and twenty native and white leghorn laying hens ranging from 36 to 43 weeks of age were used. seven experimental treatments containing different levels of salt supplied by feed and/or drinking water were compared. increasing salt int...

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...

Prostaglandin F (PGF) concentrations in the serum of laying and nonlaying hens and of cocks at various times during a day were measured by radioimmunoassay. The serum concentration of PGF was higher in laying hens than in nonlaying hens or cocks without regard to time of day. In all birds, the concentration showed a peak at 2 h after onset of light (0700 h). In laying hens on the day of laying ...

At present the laying hen rearing is transformed into alternative housing systems which include a deep litter system. As for the poultry nutrition, the replacement of animal protein with vegetable protein in poultry feed is applied. Therefore, in an experiment we evaluated the quality of eggs from laying hens in the cage system as compared to the deep litter system with vegetable protein substi...