Twenty-eight Holstein cows (4 with ruminal cannulas) were blocked by days in milk into 7 groups and then randomly assigned to 1 of 7 balanced 4 x 4 Latin square diet sequences. The diets contained [dry matter (DM) basis] 20% alfalfa silage, 35% corn silage, and 45% concentrate mainly from high-moisture corn and soybean meal. Diets differed in crude protein (CP) content and source of protein sup...

Ractopamine hydrochloride (RAC) is used in the feedlot industry to increase daily gain, improve feed efficiency, and increase HCW. However, little work has been done to determine whether additional protein is needed in the diet to maximize the benefit of RAC in beef cattle. Objectives of our experiment were to determine if feeding additional CP in conjunction with RAC would improve animal perfo...

Awassi is a multi-purpose sheep breed. Awassi lambs being finished are usually offered an 18% crude protein (CP) diet. The growth rate of Awassi lambs is lower than other meat breeds. Therefore, this high content of dietary CP is questionable. The objective of this study was to estimate the optimum CP level for finishing Awassi lambs. Fifty male Awassi lambs (23.0+/-1.2kg) were fed five high co...

To assess the effect of single low energy-low protein diet with normally required calorie: protein ratio against normal dietary NRC 1994 requirements in summer season on laying and reproductive state of Japanese quails. Forty-two days old, 60 adult and sexed Japanese quails were divided into two equal groups, 5 replicates, and 6 birds each with a sex ratio 1:5. A laying and reproductive trial e...

Two experiments (Experiment 1 and 2) were conducted to evaluate growth performance, ascites mortality, and concentrations of plasma Arg, urea, and ornithine in male broilers raised in floor pens (2 x 4 factorial experiment, six pens for treatment) and exposed to cool temperatures averaging 16 C after 21 d of age. Broilers were fed low- or high-CP diets in both Experiments. In Experiment 1, Arg ...

also supported by the FFLG data. Serum IGF-I concentrations are presented in Figure 2. Protein concentration had linear and quadratic effects (P < 0.01) on serum IGF-I concentration during weeks 2 and 4 of the experiment. There were no sex effects detected for serum IGF-I concentration, thus the data for barrows and gilts within dietary crude protein concentration were pooled and presented in F...

A trial was conducted to determine the effect of low-protein diets with constant ME:CP ratio on performance and carcass characteristics of broilers from 1 to 35 d of age. Four experimental diets were formulated to have 4 levels of CP and ME, respectively, in each phase: 23, 22, 21, and 20% CP with 3,036, 2,904, 2,772, and 2,640 kcal/kg in the starter phase (1 to 10 d); 22, 21, 20, and 19% CP wi...

Thirty-two crossbred lambs (BW = 31.2 ± 4.7 kg; 16 females, 16 males) housed in individual pens were used to investigate the relationship between nutrient supply and taste preferences in ruminants. Experiment 1 determined whether an imbalanced CP supply would alter preferences for feeds containing flavors designed to elicit either umami (U) or a mixture (1/3:1/3:1/3) of umami, sweet, and bitter...

An evaluation of muscle (pectoralis major) protein turnover using the phenylalanine flood dose technique was assessed in broiler chicks fed graded dietary lysine levels with CP at 170, 210, 250, and 290 g/kg diet. Chicks at 21 d old were injected with 1 mL/100 g BW of a phenylalanine solution (120 micromol L-[ring-2H5)]-phenylalanine). Muscle protein gain was assessed in chicks at 19 and 23 d o...

1The Alberta Crop Industry Development Fund is acknowledged for funding the project. 2Corresponding author: [email protected] ABSTRACT: The CP digestibility is traditionally measured by chemical analyses of CP and marker concentration in digesta and diets. Potentially, CP digestibility can also be predicted by marker concentrations and spectral analyses of digesta and diet. Spectroscop...