Toxicity of high dietary levels of DDT in laying hens.
White Leghorn hens were fed diets containing 0, 300, 600, or 1200 ppm technical grade DDT for three 28-day periods. The 1200 ppm diet caused tremors and 33% mortality in the final period, but no gross toxicity symptoms were seen in birds fed the other diets. Egg production was decreased during the third period by 600 or 1200 ppm. Egg weight was decreased during the third period by 600 or 1200 ppm. Egg weight was decreased during the last two periods by 1200 ppm. Shell thickness was decreased in all three periods by feeding 600 or 1200 ppm DDT. Dietary DDT caused no change that could be detected by shell beta backscatter. Shell weight as a percent of total egg weight was decreased by 600 or 1200 ppm DDT.
This experiment was designed to evaluate the effects of different sources of calcium at different rates and cholecalciferol(Vitamin D3) on the performance and egg quality of Hy-line W-36 Laying hens. In this study a total of 648 hens were managed in a completely randomized design using a factorial arrangement of 3 × 3 × 2 treatments, with three calcium sources (oyster shell, OS; ground limeston...متن کامل
Effects of Dietary Supplemental Vitamin E and Chromium on Egg Production, Egg Quality and Blood Parameters of Laying Hens under Thermoneutral or Heat Stressed Conditions
The effects of dietary supplemental vitamin E (VE) and chromium (Cr) on egg production (EP), egg quality, serum concentrations of Cr and insulin and activity of glutathione peroxidase (GSH-Px) were evaluated in Lohmann LSL-Lite laying hens reared under thermoneutral or heat stress (HS) conditions. A total of 144 laying hens were distributed in 24 cages and assigned to feed four diets including ...متن کامل
Effect of Different Levels of Mineral and Vitamin Premix on Laying Hens Performance during the First Laying Phase
An experiment was conducted to evaluate the effects of different levels of mineral and vitamin premix on performance and egg traits of laying hens from 37 to 49 weeks of age. Two hundred and forty laying hens (Hy-Line W-36 strain) were randomly assigned to 5 dietary treatments of four replicates each with 12 hens per replicate). The levels of mineral and vitamin premixes in the experiment were ...متن کامل
Sodium bentonite can bind to dietary pigment and decreases yolk color scale. Sodium bentonite is one of the main parts of Formycine® Gold, the effect of different levels of Formycine® Gold and dietary pigment on egg quality, egg yolk color and performance criteria of laying hens from 26 to 34 week of age were studied. One hundred ninety two Hy-Line hens were divided into 24 groups of 8 birds ea...متن کامل