Improving feed efficiency is a major goal in poultry production to reduce production costs and increase profitability. The genomic variants and possible molecular mechanisms responsible for residual feed intake (RFI) in chickens, however, remain poorly understood. In this study, using both local and commercial breeds, genome re-sequencing of low RFI and high RFI chickens was performed to elucid...

Genetic selection on residual feed intake (RFI) can be used as an alternative method to G:F to improve feed efficiency in pigs. The objective of this study was to determine the effects of selection for RFI on digestive and metabolic utilization of energy in 2 lines of purebred French Large White castrated male pigs obtained from a divergent selection experiment over 6 generations. The RFI(+) (h...

Since GPS signals have very low received power levels (−130 dBm, or −160 dBW), their vulnerability to RF Interference (RFI) is a serious concern. This is particularly true for GPS-based safety-critical systems such as the Local Area Argumentation System (LAAS). The Stanford LAAS Integrity Monitor Testbed (IMT) is a prototype of a LAAS Ground Facility (LGF) that is composed of various monitors t...

Improving feed efficiency is a relevant strategy to reduce feed cost and environmental waste in livestock production. Selection experiments on residual feed intake (RFI), a measure of feed efficiency, previously indicated that low RFI was associated with lower feed intake, similar growth rate, and greater lean meat content compared with high RFI. To gain insights into the molecular mechanisms u...

This study examined the relationship of residual feed intake (RFI) and performance with methane emissions, rumen fermentation, and digestion in beef heifers. Individual DMI and growth performance were measured for 22 Simmental heifers (mean initial BW 449 kg, SD = 46.2 kg) offered grass silage ad libitum for 120 d. Ultrasonically scanned muscle and fat depth, BCS, muscularity score, skeletal me...

Thirty-eight Angus-cross beef cows were used to evaluate differences in DMI, residual feed intake (RFI), and endocrine markers on the basis of cow size and RFI ranking during 2 stages of production. Cows housed in individual pens (2.2 × 9.1 m) were fed, over a 70-d feeding period, 30% Bermuda grass hay and 70% ryegrass baleage diet during lactation (LACT) and a 100% ryegrass hay diet during pos...

The objective of this research is to evaluate liver mitochondrial oxygen consumption and proton leak kinetics in progeny from two lineages of Angus bulls with high and low residual feed intake (RFI). Two Angus bulls were selected based on results from a genetic test for RFI and were used as sires. Eight offspring at 10-11 months of age from each sire were housed in individual pens for 70-105 da...

Providing feed is a major input cost in beef production, hence improvements in the efficiency of feed utilisation will reduce the cost of production. Residual feed intake (RFI) is a measure of feed efficiency, and is defined as the difference between an animal's actual feed intake and its expected feed intake based on its size and growth. It is independent of the level of production, and the lo...

A study was conducted to quantify the separate and combined impacts on selection for economic merit of including residual feed intake (RFI) traits in beef cattle breeding objectives and of having records available. RFI is a trait of interest in numerous livestock species. It was defined here for young animals at pasture (RFI-P), in the feedlot (RFI-F), and in cows (RFI-C). Results showed select...

AbsfractThis paper computes the probabilities of detection and false alarm for a pseudonoise (PN) sequence code lock detector when a strong radio frequency interference (RFI) hits the communications link. A soft-limiter, a hard-limiter, and no limiter at the front-end of the receiver are considered. Both continuous wave (CW) type RFI and pulse type RFI are analyzed. It is shown that a soft-limi...