The present study was undertaken to investigate the interactions among the supplies of isoleucine, leucine, valine, and tryptophan in laying hens. A three-factor trial was conducted with laying hens in which the dietary concentrations of isoleucine (5.7, 8.0, and 11.5 g/kg), valine and leucine (6.3 and 7.2 g/kg and 10.1 and 11.5 g/kg, respectively), and tryptophan (1.5 and 2.4 g/kg) were varied...

Applying analgesics to feed is a potentially easy method of providing pain-relief to sheep and lambs that undergo painful husbandry procedures. To be effective, the medicated feed needs to be readily accepted by sheep and its consumption needs to result in therapeutic concentrations of the drug. In the present experiment, pelleted feed was supplemented with flunixin (4.0 mg/kg live weight) and ...

Weight and feed consumption of 197 bulls were recorded monthly in a serial slaughter experiment continuing over a period of 24 mo. The bulls were produced in a modified five-breed diallel of the Angus, Brahman, Hereford, Holstein and Jersey breeds. Our objective was to estimate efficiency of feed conversion for weight gain for each breed and cross. The model included average weight gain per day...

This study was carried out to investigate the effect of different body weight groups (light (L) = 1 400–1 500; medium (M) = 1 500–1 600 and heavy (H) = 1 600 < g) on performance and egg quality traits of Lohmann hens, 24 weeks of age, in different laying periods. A total of 288 Lohmann White layers were allocated randomly to three groups with respect to live weight, each consisting of 24 replic...

In France, about 95% of the fatty liver production comes from mule ducks, an infertile hybrid cross between female common ducks (Anas platyrhynchos) and Muscovy drakes (Cairina moschata). As a hybrid, genetic improvement of the performance of mule ducks is achieved by selection of the parental populations. Feed represents two-thirds of the total costs of duck production; thus, the breeders’ mai...

In France, about 95% of the fatty liver production comes from mule ducks, an infertile hybrid cross between female common ducks (Anas platyrhynchos) and Muscovy drakes (Cairina moschata). As a hybrid, genetic improvement of the performance of mule ducks is achieved by selection of the parental populations. Feed represents two-thirds of the total costs of duck production; thus, the breeders' mai...

The aim of the present study was to compare the nutritive value of bacterial single-cell protein (BSCP) with that of fishmeal in rainbow trout (Oncorhynchus mykiss (Walbaum)). Four diets were formulated to contain a total of 458 g crude protein/kg of which 0% was from BSCP in diet 1 (BSCP-0), 25% in diet 2 (BSCP-25), 62.5% in diet 3 (BSCP-62.5) and 100% in diet 4 (BSCP-100); the remainder of th...

Two trials were conducted to determine the effect of air velocity on feed and water consumption at a constant temperature of 27 C and a daily cyclic temperature of 22-32-22 C. Air velocity over the broilers was <15 or 120 m/min. These temperature and air velocity treatments were arranged in a 2 x 2 factorial design in eight environmental chambers, with two replications of each treatment. The ai...

In the present study, 256 7-wk-old Japanese quail were randomly distributed into four experimental groups (64 birds per group) and given rations containing 0 (controls), 25, 50, or 100 (g aflatoxin B, (AFB1)/kg feed for 168 d. Each treatment consisted of four replicates of 16 quail. Egg production and individual egg weight were checked daily. Feed consumption and feed use were determined weekly...