OBJECTIVE The feed intake (FI) and feed efficiency are economically important traits in ducks. To obtain insight into this economically important trait, we designed an experiment based on the residual feed intake (RFI) and feed conversion ratio (FCR) of a random population Pekin duck. METHODS Two thousand and twenty pedigreed random population Pekin ducks were established from 90 males mated ...

Two experiments were conducted to identify factors influencing feed conversion in broilers. The first experiment was conducted to develop a test for body temperature (BT) under mild handling stress. In the first experiment, BT was recorded periodically with birds briefly restrained after they had been removed from feed with either continuous lighting or 16L:8D. Body temperature was affected by ...

Improvement of feed efficiency in pigs has been achieved essentially by increasing lean growth rate, which resulted in lower feed intake (FI). The objective was to evaluate the impact of strategies for improving feed efficiency on the dynamics of FI and growth in growing pigs to revisit nutrient recommendations and strategies for feed efficiency improvement. In 2010, three BWs, at 35±2, 63±9 an...

Two trials were conducted to test the hypothesis that broilers classified as good rather than poor feed converters (low vs. high feed-to-gain ratios, respectively) would show decreased activity (increased lethargy) and reduced fear of human caretakers. In both trials birds were reared to juvenile selection age when the 192 males with the "best" breast and leg conformation were placed into indiv...

The present study aimed to investigate the effects of dietary supplementation of multi-enzyme on productive performance of laying hens fed different levels of safflower meal. A total of 250 Leghorn laying hens (Hy-Line W-36) 47 weeks-old were randomly assigned into 10 experimental treatments with 5 replicates of 5 birds each. Experimental treatments consisted of five safflower meal levels (0.0,...

abstract 900 rainbow trout (mean weight 25 gr) were obtained from a local fish farm in urmia city and after acclimatization for 10 days, the fish were randomly divided into four groups (with three replication) and fed for 8 weeks with 0 (control), 2/5, 5 and 10 g chitosan/kg feed, respectively. finally treatments were fed the control diet (without any chitosan) for another 3 weeks. body weight,...

An experiment was conducted for sixty days to evaluate the effects of Vitamin C of formulated feed on growth performance and body composition of stringing fish, Heteropneustes fossilis (Bloch, 1792). During experimental trial in the laboratory condition, the change in growth and feed utilization by the stringing fish fed on three different Vitamin C level have been assessed by the determination...

The purpose of this study was to determine the survival rate (SR), Average Daily Growth (ADG), and Feed Conversion Ratio (FCR) Nile tilapia (Oreochromis niloticus) with a dynamic system model. model is used optimal value three variables. results showed that rate, average daily growth, feed conversion ratio cultivation were 93% 3.2gr/day 0.73 (FCR). In research, production 14,199gr, amount 10.34...

Variation in residual feed intake, that is, variation in feed intake in relation to liveweight (LW) and growth rate, was investigated using data from 540 progeny of 154 British Hereford sires, collected over ten 200-day postweaning performance tests conducted between 1979 and 1988. Residual feed intake (RFI ) was calculated for each test as the difference between Reg actual feed and expected fe...

Studies were conducted to determine the effects of high dietary ascorbic acid (vitamin C) on growth performance and body composition of a commercially important Asian catfish, Clarias batrachus. During experimental trial in the laboratory condition, the change in growth and feed utilization by the Clarias batrachus fed on three different Vitamin C level have been assessed by the determination o...