Commercial Broiler Diet Research Articles

Environmental Temperature and Dietary Lysine Effects on Free Amino Acids in Plasma

Broiler chicks were reared to 5 weeks of age in environmental chambers maintained at 7.2°C. and 32.2°C. with dewpoints of 0° and 10°C., respectively. In 2 trials chicks were fed commercial broiler diets and in 3 trials they were fed diets supplying 60, 100 and 130 percent of the dietary lysine requirement.Free amino acids in plasma were measured. Chicks at 7.2°C. had reduced concentrations of alanine, arginine and tyrosine but had increased levels of cystine, ornithine and lysine, when compared to the values for chicks at 32.2°C. The increased plasma lysine could result from its relative difficulty of catabolism in comparison with the other amino acids. It is suggested that the high level of plasma lysine in chicks kept at 7.2°C. results in an increased breakdown of arginine to ornithine.

Fish Meal Studies: 1. Effects of Levels and Sources on Broiler Growth Rate and Feed Efficiency

CONSIDERABLE data have been accumulated concerning the value of fish meal as an ingredient for broiler diets. The literature concerning the use of fish meal has been extensively reviewed by Menge et al. (1952), Branion and Hill (1953), Rasmussen et al. (1957), and Harms et al. (1961).In commercial broiler diets, the amount of fish meal is usually limited due to the possibility of producing off-flavors in the meat. This problem is reviewed in the following paper by Fry et al. (1965).In certain areas or countries where large amounts of fish meal are produced, it may be economically feasible to use fish meal as the major protein supplement in the diet of broiler chicks. The purpose of the studies reported herein was to determine the response in growth and feed efficiency of broilers as a result of a replacement of part or all of the soybean meal in the…

The Influence of Solvent Extracted Fish Meal and Stabilized Fish Oil in Broiler Rations on Performance and on the Flavor of Broiler Meat

HIGH quality fish meal is an excellent source of protein for growing chicks, as reported by Hinners and Scott (1960). However, in commercial broiler diets, fish meal is usually limited to less than 10 percent to avoid possible fishy flavor in broiler meat. Fishy flavors or “off-flavors” in meat have been attributed to fish oil by Carrick and Hauge (1926), and Asmundson et al. (1938). The levels of dietary fish oil that have been reported to cause fishy flavor of meat varies, but most workers seem to agree that 2 percent fish oil will certainly produce off-flavored meat.Rand et al. (1960) and Common et al. (1957) report that aging or heating produces a toxic degradation product of fish oil.Singsen et al. (1954) produced encephalomalacia in chicks having low levels of tocopherols at hatching using diets containing 2 percent unstabilized fish oil. Encephalomalacia was prevented by the addition of…