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Showing 1 to 20 of 20 for “"Residual feed intake"”.
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The relationship between mitochondria and residual feed intake in feedlot cattle
Residual feed intake (RFI) is a measure of feed efficiency that is not related to an animal's growth rate or body size. Little is known about the factors that affect RFI because, until recently, the measurement of RFI in large numbers of animals was not possible. Recently, researchers have shown a …
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The Relationship between Residual Feed Intake, Dry Matter Intake, and Reproductive Performance in Holstein Dairy Cows
Feed represents a large portion of input costs for dairy operations. Decreasing the feed consumed, measured here as dry matter intake (DMI), would therefore be advantageous to producers. However, this decrease could result in cows that do not supply the necessary energy to maintain high production, …
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RESIDUAL FEED INTAKE AND THE RELATIONSHIP WITH PERFORMANCE, TEMPERAMENT AND CARCASS TRAITS IN GROWING AND FINISHING STEERS
… were weighed at 14-d intervals and dry matter intake (DMI) measured for 70 d during both phases. Residual feed intake (RFI) is the difference between actual DMI and DMI predicted from linear regression of DMI on mid-test metabolic body weight. Ultrasound carcass measurements were measured on …
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Residual feed intake, breed of sire and dam, and individual sire affect performance and carcass characteristics and rates of back fat and intramuscular fat of feedlot steers
… into high (H), medium (M), and low (L) residual feed intake (RFI) groups. Steers in the H RFI group ate 1 kg more of DMI (P< 0.05) per day than steers in the L and M RFI group. Steers in the L RFI group had the highest feed efficiency by gaining 15% and 22% more per kg of feed than …
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Effects of Nutrition and Management on Feed Efficiency, Carcass Value, and Profitability in Feedlot Cattle
… influence of sire, diet, and body composition on feed efficiency and profitability. Diet digestibility was higher for corn based finishing diets and lower for diets containing wet corn gluten feed (WCGF). Average daily gain was the lowest for the diet containing WCGF. Dry matter intake was lower …
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Factors influencing cow performance and intake
ABSTRACT FACTORS INFLUENCING COW PERFORMANCE AND INTAKE Two studies were conducted to determine how weaning system, residual feed intake (RFI), and residual average daily gain (RADG) affect cow performance and intake. In Study 1, a two-year study was conducted using Angus and Simmental X Angus …
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Nitrogen balance and nutrient requirements of young Nellore bulls fed with static or oscillating crude protein levels, and feeding behavior, water intake and requirements of bulls with different residual feed intakes
… effects of dietary crude protein (CP) supply on intake, digestibility, performance, N balance, and requirements of young Nellore bulls, and 2) to determine feeding behavior, water intake, and requirements of high and low residual feed intake (RFI) Nellore bulls. 42 young bulls (initial BW of 260 …
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Methods to improve growth efficiency in beef cattle
… growth efficiency of domestic livestock. Residual feed intake (RFI) is an accurate method of distinguishing between feed efficient and inefficient animals. Because RFI is independent of growth and BW it can be selected upon without influencing mature size of the animal. Yet some of the …
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Effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers
… the effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers. In experiment I, which included 90 Angus-sired steers from four calving seasons, early weaning followed by a short ad libitum concentrate-feeding and …
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Evaluation of intake and feed efficiency measures in beef cattle
Four experiments were conducted to evaluate intake and measures of feed efficiency in beef cattle. In Exp. 1 and 2, measures of feed efficiency were calculated on Angus and SimAngus heifers (Exp.1; n = 623, and Exp. 2; 404); and heifers were classified as either high, medium, or low residual feed …
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Reduction of minerals in feedlot diets of Nellore cattle: impacts on intake, performance, and nutrient requirements; and prediction of chemical rib section composition by dual energy x-ray absorptiometry in Zebu cattle
… 2 × 2 factorial design experiment to evaluate intake, fecal excretion and performance with different levels of minerals. The design included two levels of Ca and P (macro mineral factor; CaP+ or CaP-) and two levels of micro minerals (micro mineral factor; ZnMnCu+ or ZnMnCu-). The factor CaP- …
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METHANE MITIGATION, FEED EFFICIENCY, AND HEAT STRESSIN REPLACEMENT HEIFERS: NUTRITIONAL ANDMANAGEMENT APPROACHES FOR SUSTAINABLE DAIRYPRODUCTION
… In particular, the research focused on improving feed efficiency, mitigating methane emissions, and alleviating the detrimental effects of heat stress in Italian Holstein dairy heifers. The first study (Chapter 3) describes an in vivo trial evaluating the inclusion of increasing doses of lysozyme …
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Influence of feed efficiency ranking and maternal nutrition on gut microbiome, metabolome, and transcriptome in beef and dairy cattle
Residual feed intake (RFI) describes an animal’s feed efficiency independent of the level of growth and production performance. The RFI has become a commonly used measure for feed efficiency in beef and dairy cattle. The first experiment was to determine differences in major ruminal bacteria and …
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Genotype by environment interaction for feed efficiency in growing-finishing pigs in Brazil versus the Netherlands
… main goals of modem pig breeding 1s to improve feed efficiency of crossbred (CB) pigs across the diverse, and often challenging, environments in commercial farms. The main aim of this thesis was to investigate the existence and magnitude of genotype by environment interaction for feed efficiency …
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The Evaluation of Genetic and Phenotypic Differences Associated with Short Term Selection of Four Different Feed Efficiency Strategies in Japanese Quail
<p>The concept of feed efficiency (FE), one unit of feed required to improve one unit of desired output, is relatively simple. However multiple outputs are desired in a commercial poultry breeding program, resulting in the need for nutrients to be partitioned in a particular manner. At the broadest …
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Evaluation of feedlot feed efficiency relationships as well as genetic and phenotypic performance, carcass, and economic outcomes
Several feed efficiency values have recently been proposed including: feed conversion ratio in terms of feed:gain (FCR), residual feed intake (RFI), and residual BW gain (RG), and residual intake and BW gain (RIG). These all have production efficiency potential since they include feed intake inputs …
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Determining the added value of coproducts based adaptation diets and the heritability of variation in feed intake in Red Angus cattle
The main goal of the feedlot industry is to maximize growth in cattle while minimizing costs in all phases of the finishing period. Traditionally, this is done by feeding diets high in grain to maximize energy intake. However, cattle coming to the feedlot are typically consuming diets high in …
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Fetal programming in cattle: the effects of varying maternal protein intake in adolescent beef heifers on fetal and postnatal growth and development of the calf
… investigates the effect of low and high protein intake in nulliparous beef heifers during the peri-conception and first trimester of gestation upon feto-placental growth and the subsequent postnatal growth and reproductive development of the male offspring. Furthermore, the impact of maternal …
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Identification and characterization of genetic markers and metabolic pathways controlling net feed efficiency in beef cattle.
Net feed intake or residual feed intake is the feed intake of an animal after adjustment for its average weight and weight gain while on the feed test. High net feed efficiency (NFE) animals have a low net feed intake, so the aim is to select animals that have high net feed efficiency in order to …
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Study of genetic by environmental interactions at transcriptomic and genomic levels
… cost in the beef cattle industry comes from feed and may represent from 62 to 84% of the total costs. In this manner, the relationship between feed intake and production needs to be assessed. The genomic potential for feed efficiency was evaluated in a feedlot beef cattle population in two …