Laying hens were fed diets containing sunflower, fish, linseed and rapeseed oil with 2 levels of inclusion (1.5 and 3.0%) for 12 weeks. Egg production, egg weight, feed intake, feed conversion and liveweight were not significantly affected by the treatments. Hens receiving sunflower oil produced less intensively coloured egg yolks than those received other oils in their diet (P<0.01). The fatty acid composition of the egg yolk was significantly (P<0.01) affected by the treatment, while cholesterol content was not influenced. There was a significant (P<0.05) interaction between fat source and the level of inclusion in the diet, linolenic acid content increased when hens were fed diet with 3% of linseed and rapeseed oil. Dietary fish oil significantly (P<0.01) increased the deposition of docosohexaenoic acid in the egg yolk. Sensory panelists scored as unacceptable those eggs from hens provided feed with 3% fish oil.

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1. The aim of the study was to investigate the effects of dietary threonine (Thr) and crude protein (CP) in maize-soybean meal based diets on the growth performance, carcase traits and meat composition of broiler chickens and to determine the dietary Thr requirement for optimum performance (weight gain and feed conversion efficiency (FCE)) at 0 to 3 weeks and 3 to 6 weeks of age. 2. Two basal diets that differed in CP (191.3 or 179.7 and 176.7 or 165.4 g/kg at 0 to 3 and 3 to 6 weeks, respectively) were formulated to have identical contents of Thr (6.0 and 5.4 g/kg), energy (12.97 and 13.39 MJ ME/kg) and other essential amino acids except for Gly + Ser. Basal diets were supplemented with L-Thr from 0.6 to 1.8 g/kg in 0.6 g/kg increments. Broiler chicks (540) were randomly allocated to 9 dietary treatments with 6 replicates of 10 (5 female, 5 male) chicks. 3. A significant interaction between dietary CP and Thr was found for feed intake, body weight (BW) gain and FCE. Increasing Thr supplementation improved feed intake, BW gain and FCE, especially in high CP diets in both feeding periods. 4. Incremental increases in dietary Thr increased breast yield at both CP levels and drumstick yield only on high CP diets. The proportion of thigh decreased with Thr concentration. Liver weight was significantly reduced by Thr supplementation; abdominal fat was not affected. 5. Estimated Thr requirements for FCE increased as dietary CP increased according to an exponential model. This model indicated higher Thr requirements than those of broken-line models for growth performance.

In this experiment, the chloride analyses methods for testing mixing homogeneity and effects of diets of different homogeneity on broiler performance were investigated. Two hundred and forty day-old broiler chickens were used in three treatments with four replicates, each of 10 males and 10 females. The experiment was conducted in three feeding phases (starter 0-2, grower 3-5 and finisher 6 th week of age) and terminated on day 42. According to the results of preliminary mixer evaluation based on values of salt analysis, it was estimated that 0.20, 0.59, and 3.75 min mixing times were required for CVs of >20, 20 to 10 and <10% of diet uniformity, respectively. Experimental feeds were produced considering these mixing times. Chloride analysis of samples was performed using titrimetric and Merckquant methods. The correlation between CVs of the titrimetric and Merckquant chloride test was statistically significant (r=0.92, P=0.0009).No significant differences were obtained among treatments for average liveweight gain, feed intake, feed conversion, mortality, carcass yield and abdominal fat pad percentage. However, CV of final BW was numerically reduced with increase in mixing time.

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