OBJECTIVE This experiment investigated the effects of dietary supplementation with conjugated linoleic acid (CLA) on the serum components, laying hen productivity, lipid composition of egg yolk, egg flavor and egg quality. METHODS Healthy 28-week-old Hy-Line white laying hens (n = 480) were divided randomly into 4 groups, 6 replicates/group, 20 birds/replicate. The 30-day experimental diets i...

An experiment was conducted with 72 Bovans Brown laying hens to determine the effect of dietary crude glycerin on laying performance; egg quality; retention of N, Ca, and P; and metabolizability of energy. The dietary treatments consisted of a control corn-soybean diet containing 6% corn starch (17% CP, 2,775 kcal/kg of AME(n), 0.81% lysine, 0.36% methionine, 3.60% Ca, and 0.37% available P) an...

OBJECTIVE This study was conducted to evaluate the effects of dietary protein sources (soybean meal, SBM; low-gossypol cottonseed meal, LCSM; double-zero rapeseed meal, DRM) on laying performance, egg quality, and plasma parameters of laying hens. METHODS A total of 432 32-wk-old laying hens were randomly divided into 6 treatments with 6 replicates of 12 birds each. The birds were fed diets c...

In this experiment, the effect of prebiotic Bio-Mos® (MOS) and types of feed formulation (total and digestible amino acids) were evaluated on performance and the small intestine microflora in laying hens for a duration of 10 wks. A total of 168 Hy line W-36 laying hens, with an initial age of 73 wks, were randomly allocated to 4 dietary treatments, 7 replicates and 6 birds in each replicate. Th...

The oviposition process of the red imported Þre ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), is described as a succession of four events forming one egg-laying cycle. Each time an egg is laid, the vulva opens and the sting is fully extended. When the vulva closes, the egg is forced to the base of the sting, whereupon the sting is usually retracted across the egg. This phenomenon has...

CRBP1 (cellular retinol binding protein 1) and CRBP3 (cellular retinol binding protein 3), are important components of the retinoid signaling pathway and take part in vitamin A absorption, transport and metabolism. Based on the role of vitamin A in chicken laying performance, we investigated the polymorphism of CRBP1 and CRBP3 genes in 349 chickens using single strand conformation polymorphism ...

Laboratory experiments tested whether two economically-important sibling species of tephritid fruit flies have evolved distinct egg-laying responses to chemical stimuli on the fruits of their respective hostplants. The egg-laying preferences displayed by apple maggot flies, R. pomonella, and blueberry maggot flies, R. mendax, on artificial fruits treated with apple and blueberry extract paralle...

this experiment was conducted to determine the effect of using l-threonine and reducing dietary levels of crude protein (cp) on egg production criteria in layers. three hundred of hy-line w36 laying hens were used in this experiment. this experiment consisted of three experimental treatments with five replications in each. experimental treatments included 3 diets with different levels of cp whi...

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...

this study was conducted to evaluate the effects of different levels of butyric acid triglyceride and prebiotics on performance, egg quality traits and blood lipids of laying hens.  a 2 × 4 factorial experiment with 4 levels of butyric acid triglyceride (0%, 0.15%, 0.30%, 0.45%) and 2 levels of prebiotic (0 and 0.15%) based a completely randomized design were conducted. one hundred and ninety-t...