Influence of feeding supplemental fat by age sequence on the performance of growing turkeys

Effect of nutrient density and energy to protein ratio on performance and carcase quality of small white turkeys

One thousand eight hundred Small White turkeys were fed diets of 3 nutrient densities, representing approximately 0, 30 and 90 g added fat/kg of diet, or a fourth treatment which provided increasing nutrient densities from 6 weeks of age to slaughter at 12, 13 and 14 weeks. Within each nutrient density, 4 energy to protein ratios were derived by reducing dietary protein. Each increment in nutrient density resulted in increased body weights and improved efficiency of food utilisation. Increasing energy to protein ratio resulted in linear decreases in body weights, food intake and efficiency of food utilisation. Carcase quality, as measured by carcase fat scores and percentage of grade A carcases, improved with each increment in nutrient density and declined with increasing energy to protein ratio. Progressively increasing nutrient density from 6 weeks of age resulted in body weights, efficiencies of food utilisation and carcase finishes intermediate between those of the medium and high density groups. Such a programme avoids the disadvantages of feeding high nutrient density diets through much of the growing cycle, while providing growth, efficiency of food utilisation and carcase grades approaching those produced by the full high nutrient density programme.

The effect of graded levels of corn oil and different fats on the performance of white pekin ducklings

One-hundred-eighty male and female ducklings (90 of each sex) were fed isocaloric and isonitrogenous diets formulated to contain 0, 2, 4, 6, 8, or 10% corn oil in the starter (0 to 14 days), grower (14 to 35 days), and finisher (35 to 49 days) periods. Body weights of the ducklings were not different among treatments; however, feed consumption decreased significantly between 0 and 49 days of age (10.22, 9.78, 9.18, 9.00, 8.54, and 8.96 kg) as the level of dietary corn oil increased (0, 2, 4, 6, 8, and 10%, respectively). Regression analysis indicated a linear decrease in feed/gain (F/G) as corn oil increased in the diet. F/G (0 to 49 days) = 3.48 - .06 (% corn oil); r2 = .92. In a second experiment, isocaloric and isonitrogenous diets were formulated to contain 0% added fat (NF) or 4% corn oil (CO), peanut oil (PO), vegetable shortening (VS), lard (LD), or tallow (TL). The body weights of the ducklings were the same across treatments throughout the 49-day experiment. Ducklings fed 4% TL consumed significantly (P less than .05) less feed than those ducklings fed NF, PO, VS, or LD. Feed efficiency was not statistically different among the ducklings fed the six different diets.

Independent effects of dietary metabolizable energy and protein concentrations on performance and carcass characteristics of Tom turkeys

An experiment was conducted to determine the independent and interaction effects of dietary metabolizable energy (ME) and protein concentrations on performance of Large White toms from 9 to 20 weeks of age. Diet treatments consisted of a complete factorial arrangement of three ME concentrations and three protein concentrations within each age interval (9 to 12, 12 to 16, and 16 to 20 weeks). The different ME concentrations were obtained by using an animal-vegetable fat blend at 0, 4, or 8% of the diets. Dietary protein levels tested provided approximately 88, 97, or 107% of those recommended by National Research Council (1977) for each age interval. The ME concentrations represented 95, 100, or 105% of those used most frequently in commercial feeding programs in the central United States. Dietary ME and protein concentrations had significant (P less than .03) independent effects on turkey performance. As each diet variable was increased, gain in body weight and feed efficiency were improved. Increasing dietary ME reduced the amount of protein consumed per kilogram of gain but not the ME consumed per kilogram of gain. Protein consumed per kilogram gain increased as dietary protein increased, while ME intake per kilogram gain decreased. Carcass composition and parts yield of the carcass were affected only slightly by dietary ME and protein concentration. No significant (P greater than .10) interaction effects of dietary ME and protein were detected, except in the instance of absolute quantity of carcass protein (P less than .07).(ABSTRACT TRUNCATED AT 250 WORDS)