In the beef production system, 70-75% of the total dietary energy is used for maintenance (Ferrell and Jenkins 1984; NRC 1996; Montaldo-Bermudez et al. 1990). Thus, while only 5% of the total life cycle dietary energy consumption is used for protein deposition in beef cattle, swine and poultry are more efficient at 14 and 22%, respectively. The relatively large size, slow maturity and slow repr...

and Implications The relationships between body condition score (BCS) observed during the first 45 days of lactation and two measures of feed efficiency, residual feed intake (RFI) and gross efficiency (GE) defined as milk energy / DMI, measured during mid-lactation were assessed in 255 first lactation Holstein cows. No significant differences in BCS at calving and at approximately 40 days in m...

Net feed intake (NFI) is a moderately heritable feed efficiency trait that has been shown to be genetically independent of ADG and BW in beef cattle. Objectives of this study were to characterize NFI in growing bulls, and to examine phenotypic correlations between NFI and performance, body composition, and fertility traits. Net feed intake was positively correlated phenotypically with feed conv...

one experiment was conducted in order to evaluate four levels of macaroni waste including: 0, 10, 20 and 30 percentage in growing turkey feed in a completely randomized design (crd) with 120 local turkey including 3 replicates in 12 pens. during the experiment (3-8 weeks), turkeys received feed and water of free access. weight gain, feed consumption and feed efficiency were measured weekly. dif...

Genetic improvement of feed efficiency is key to improve the economic and environmental sustainability fish farming. However, it requires individual phenotypes efficiency, which are difficult if not impossible obtain when reared in tanks or cages. Here, we applied validated on gilthead sea bream a method evaluate based rearing aquariums under restricted feeding. We collected 538 (average weight...

Improvement of feed efficiency can be achieved by genetic selection directly on feed to BW gain ratio or for alternative traits. In the present study, 2 different traits were explored in the growing rabbit and their heritability and genetic correlations with traits recorded between weaning (30 d) and 63 d of age: i) residual feed intake (RFI), to select animals having low ad libitum feed intake...

Feed intake and efficiency are economically important traits because feed is the greatest variable cost in beef production. Feed efficiency can be measured as residual feed intake (RFI), which is the difference between actual DMI of an animal and the expected DMI based on its BW and growth rate. Feed conversion ratio (FCR) is the inverse of gross feed efficiency and is the ratio of DMI to ADG. ...

this experiment was conducted to evaluate the effect of spirulina pletensis powder on the growth performances (final weight (fw), daily growth ratio (dgr), feed indices (feed conversion rate (fcr), voluntary feed intake (vfi), protein efficiency ratio (per), protein produce value (ppv), body chemical (protein, fat, moisture and ash) and fatty acid composition of mugil cephalus for 62 days. the ...