Rationale Ecologists increasingly determine the ?15N values of amino acids (AA) in animal tissue; “source” AA typically exhibit minor variation between diet and consumer, while “trophic” have increased consumers. Thus, trophic-source offsets (i.e., ?15NT-S) reflect trophic position a food web. However, even variations ?15Nsource may influence magnitude offset that represents step, known as disc...

The NRC (1996) changed from the factorial protein system to a metabolizable protein (MP) system for beef cattle. In the MP system, dietary crude protein (CP) is subdivided into degraded intake protein (DIP) and undegraded intake protein (UIP). The quantity of microbial protein produced in the rumen dictates DIP requirements. Steam-flaked corn is the predominant grain used in the diets of finish...

1. Possible associations between maternal nutrition in pregnancy and non-communicable diseases of adulthood were assessed using a rat model. Rats were habituated to diets containing a range of protein levels (18, 12, 9 and 6% by weight), over a 14 day period, before mating. The low protein diets were maintained throughout pregnancy. Lactating mothers and their offspring were transferred to a st...

I . A total of six diets based on maize silage were formulated to examine the effect of proteinand non-protein-nitrogen, and energy supplementation on the flow of amino acids to the small intestine and the synthesis of microbial amino acids in the rumen of growing cattle. All diets contained 24 g total nitrogen (N)/kg dry matter (DM), of which 550 g N/kg total N was supplied by either urea or f...

metabolizable protein (mp) supply and amino acid balance were manipulated through selection of highly digestible rumen-undegradable protein (rup) sources. effects on production efficiency and n utilization of early post-partum dairy cows were determined. forty-two multiparous and 16 primiparous holstein cows were assigned to the diets in a randomized complete block design immediately after part...

The present study examines the effects of dietary saturated (hydrogenated coconut oil) and polyunsaturated (salmon oil) fats on the composition and metabolism of lipoproteins in growing rats fed on protein-deficient diets, Four groups of rats were fed on the following diets for 28 d: 200 g casein + 50 g coconut oil (COC)/kg, 20 g casein + 50 g coconut oil (COd)/kg, 200 g casein + 50 g salmon oi...

Previous experiments with Senegalese sole (Solea senegalensis) have demonstrated that dietary lipid levels above 8% impaired growth and did not promote protein retention. We hypothesised that this low ability to use high-lipid diets may depend on the dietary protein level. In the present study, a 2 × 2 factorial design was applied where two dietary lipid (4-17% DM) and two dietary protein (belo...