Download or read book Phenotypic Relationships Between Residual Feed Intake Feeding Behaviour and Temperament in Western Canadian Beef Cattle written by Lindsey Lippens and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed costs have led the cattle industry to examine the merit of selecting cattle for inputs (feed efficiency) rather than for outputs exclusively (growth). Residual feed intake (RFI) has become a preferred measure of biological efficiency. Feeding behaviour traits (feeding event duration, frequency, head-down time, length and eating rate) and temperament may provide insight into the variation in feed efficiency. Feeding behaviour, RFI (n = 868) and temperament (n = 58) were examined using five classes of beef cattle. Cattle were sorted into low, medium and high RFI groups. Feeding behaviour traits were moderately (-0.21 to 0.56; P 0.05) related to RFI. Bulls fed a grain-based diet spent longer periods lying down than bulls fed a forage-based diet. No relationships (P 0.1) were observed between RFI and bull temperament, indicating that temperament is not correlated with RFI and selecting for low RFI cattle will not negatively impact temperament.

Download or read book Identification of Feed Intake Traits Related to Beef Reproductive Improvement written by Cameron Alexander Olson and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reproductive efficiency in the Western Canadian beef cow herd has not improved over the past 3 decades, despite consistent and measurable improvement in several related areas of production. The general objective of this thesis was to evaluate the relationships between early-observation traits (feeding behaviour), weight change, and reproductive efficiency in beef cows. Estimates of total dry matter intake and the relationship between residual feed intake (adjusted for body composition; RFIFAT) observed in heifers and mature cows were also evaluated as traits of interest and use to the Canadian beef industry. Chapters 3 and 4 investigated the relationship between feeding behaviours and reproductive efficiency and provided phenotypic and genetic correlations that may be of use in selecting heifers with greater reproductive potential if those heifers have feeding behaviours reported. Feeding behaviour and reproductive efficiency were both correlated with dry matter intake; feeding behaviours that promote dry matter intake may be useful in the identification of heifers with greater reproductive potential. Chapter 5 evaluates the usefulness of tracking cow weights over time and the usefulness of comparing cow weights to an idealized growth curve estimation. Generally, cows that gained weight over time were more likely to be culled for reproductive failure, and the same was true for cows that were heavier than their estimated body weight. Producers may be able to use weight-monitoring technology currently available and in development to identify cows that abort their calves after a positive pregnancy evaluation and remove them from their herd at a time when feed resources are expensive. Chapter 6 was a comprehensive and unique estimation of cow dry matter intake over time, including energy estimates based on birth, weaning, residual feed intake tests as a heifer and as a cow, and subsequent calving events with associated energy expenditures for milk production. These estimates were compared to genomic retained heterozygosity, breed composition, and winter-feeding environment to evaluate the effects of those variables on dry matter intake predictions. Chapter 7 investigated the relationship between heifer residual feed intake and residual feed intake observed in the same animals as mature cows. Residual feed intake in heifers can be used to select cows that maintain a proportion of their efficiency observed as heifers, and ultimately provides evidence that the selection of feed-efficient heifer calves as replacement animals should result in a more efficient mature cow herd. This thesis provided evidence to support the selection of heifer replacements using feeding behaviours observed during a feed intake test, the use of weight monitoring technology to identify cows that may have had reproductive issues. This thesis also provided some of the first estimates of dry matter intake over the course of the production cycle in a large number of animals under normal production environments and provided estimates of the relationship between heifer and cow residual feed intake.

Download or read book Characterization of Feeding Behavior Traits and Associations with Performance and Feed Efficiency in Finishing Beef Cattle written by Egleu Diomedes Marinho Mendes and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The first objective of this study was to validate the feeding behavior measurements from a radio frequency electronic system (GrowSafe (TM) System Ltd., Airdrie, AB, Canada) and examine the software sensitivity to different parameter settings (MPS) to quantify feeding behavior traits. Data was continuously recorded 24 h per day using the GrowSafe (TM) system for 32 heifers over 81-d. Ten animals were randomly selected and evaluated over 6-d using time-lapse video recordings. Different parameter settings (MPS) from the electronic system (GrowSafe (TM)) used to record feeding behavior data, bunk visits (BV) frequency and BV duration, were compared with the observed (video) values. The second objective of this study was to quantify meal criterion; examine the associations between feeding behavior traits, performance, and feed efficiency; and the effects of breed type on feed efficiency (residual feed intake - RFI) and feeding behavior traits in heifers fed high-grain diets. Results from study one demonstrated that the GrowSafe (TM) system 4000E could accurately predict BV and meal data compared to observed data. The 100 s, used for the maximum duration between consecutive EID recordings to end an uninterrupted BV, was the appropriate MPS to predict BV frequency and duration, and meal frequency and duration compared to observed data using the GrowSafe (TM) 4000E system. The system's ability to detect the animal's presence or absence at the feed bunk was 86.4 and 99.6 percent, respectively. Results from the second study demonstrated that the meal criterion for heifers fed high-grain diets was 13.8 min. The 4 methods to calculate meal criterion demonstrated no differences in results of frequencies and durations of meal and the number of bunk visits per meal. Similar phenotypic correlations were found between the feeding behavior traits with RFI derived from the base model or with adjustments for final back fat. The adjustment of RFI to final back fat changed the RFI rank between breeds. The addition of feeding behavior traits to the RFI base model could accounted up to 40.4 percent of the variation in DMI not explained by ADG or MBW.

Download or read book Residual Feed Intake in Beef Cattle in Relation to Breed Selection and Behavior written by Marcus McGee and published by . This book was released on 2014 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed efficiency is a necessary factor in beef production systems due to rising feed ingredient costs, population growth, and beef supply demands. With this known, it is important for researchers to delve into mechanisms involved in efficiency to provide producers with a knowledge base for future selection and breeding programs. Though the use of residual feed intake (RFI) is fairly well know, traditional traits are often considered more desirable due to costs associated with testing. However, previous research has provided evidence of benefits using a less biased measurement (RFI) in comparison with its counterparts (e.g. ADG, FCR, F:G etc.) Though RFI does provide indication of efficiency status, there are underlying mechanisms that also play a role in these measurements that are not completely understood. One attribute of efficiency often overlooked is feeding behavior, in which this body of work attempts to interpret via relationships with RFI. Previous research has provided has examined relationships between these two parameters, however further studies are necessary to gain a more solid foundation. Research within this dissertation will add to this knowledge base using two breeds of cattle examined for behavior traits (bunk visit frequency, bunk visit duration, feed bout frequency, feed bout duration, meal frequency, meal duration, and average meal intake) during the course of RFI evaluation. Niche breeds of beef cattle (e.g. Japanese Black Cattle) are often excluded from feed efficiency examinations, due to focuses of output, carcass quality traits, and increased specialty market value. However, the recent rise of feed ingredient costs are universal, and producers of niche breeds may benefit as well. Within this body of work, 3 cohorts of Wagyu cattle were evaluated for feeding behavior parameters with some insight towards relationships with efficiency. Red Angus cattle were also evaluated over both growing and finishing phase RFI to clarify feeding behaviors' role in efficiency. Results from these studies provide researchers with additional tools for elucidating these relationships as well as identifying specific feeding behaviors that contribute to efficiency status in beef cattle.

Download or read book Determining Variables Linked to the Phenotypic Expression of Feed Efficiency Using Residual Feed Intake as a Measure of Efficiency written by Joseph Walter Golden and published by . This book was released on 2004 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed represents 60 to 70% of the cost of raising an animal to market weight, and is thus a major determinant of profitability. The task of collecting and analyzing individual feed intakes and feed efficiencies has limited the amount of research conducted to improve feed efficiency, and thus profitability. Thus, selection for growth has received more emphasis in genetic improvement schemes in comparison to improvement of feed efficiency. The utilization of robust and innovative technologies has allowed for the collection of individual feed intakes and feeding behaviors and allowed for more expansive research in determining and understanding the variables linked to the phenotypic expression of feed efficiency. Two studies utilizing GrowSafe technologies were conducted to determine the relationship of mitochondrial function and feeding behavior to the phenotypic expression of feed efficiency. (Abstract shortened by UMI.).

Download or read book The Relationship Between Residual Feed Intake Feeding Behaviors Feed Intake and Evaluation of Sampling Error Associated with Post Weaning Gain Tests written by William C. Kayser and published by . This book was released on 2014 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed is the largest variable cost associated with beef production, any reductions of feed inputs whilst maintaining outputs will result in direct increased profitability for the industry. Traditionally individual feed intake has been expensive and laborious to measure. Recent improvements in technologies for measuring individual feed intake have made incorporating the phenotype into breeding selection decisions possible. Residual feed intake (RFI) is defined as the amount of feed that an animal consumed adjusted for the expected consumption based upon requirements for maintenance and growth. RFI is independent of body weight (BW), gain (ADG), carcass and meat quality. RFI is highly correlated with feed intake (DMI) and moderately heritable (r = 0.40). There are differences in feeding behaviors amongst the divergent RFI classes, animals with low RFI tend to spend less time eating per day and have fewer overall meals per day. There are many documented differences between low and high RFI animals, by adding to the knowledge base on RFI there should be increased producer and industry adoption.

Download or read book The Relationship Between Performance Residual Feed Intake and Temperament Assessed in Growing Heifers and Subsequently as Three year Old Suckled Beef Cows written by Tera Elizabeth Loyd and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Heifers were ranked by RFI and placed into Low (most efficient; 0.5 SD; n = 24), Med (0.5 SD; n = 24), and High (least efficient;0.5 SD; n = 26) RFI groups. Initial BW, final BW and ADG were similar among groups. However, daily DMI differed for all groups (P

Download or read book Feed Intake and Feeding Behavior Associations with Performance and Feed Efficiency of Feedlot Cattle Fed a Corn based Diet written by Jayton Bailey and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the first study was to determine which combination of bimodal (2-population) distribution models best fit non-feeding interval data to distinguish intervals within (1st population) and between (2nd population) meals in beef cattle fed a corn-based diet. Feeding behavior traits were measured in 119 heifers fed a corn-based diet using a GrowSafe system. Bimodal distribution models were fitted to the log10-transformed interval lengths between bunk visit (BV) events for each animal using Gaussian (G); Weibull (W); Log-Normal; Gamma and Gumbel statistical functions. Criterion (AIC) and likelihood probability estimates. Objectives of the second study were to quantify individual meal criterion and examine the associations between feeding behavior traits, performance, and feed efficiency traits in heifers fed a corn-based diet. Results from study one indicate that the G-W bimodal distribution model is a statistically better fitting and likely a more appropriate model to define meal criterion compared to the standard G-G model used in previous literature. Results from the second study suggest that the meal criterion for heifers fed a corn-based diet is 11.48 min when applying the G-W bimodal model to log-transformed interval lengths between BV events. Moderate phenotypic correlations between feed efficiency (residual feed intake- RFI) and several feeding behavior traits were found. Inclusion of these feeding behavior traits to the base model for RFI accounted for an additional 25% of the variation in DMI not explained by ADG or mid-test BW0.75. Significant (P

Download or read book Phenotypic Characterization of Feed Efficiency and Feeding Behavior Traits in Performance Tested Bulls Fed a Corn Silage Based Diet written by Jose Gilberto Moreno Rajo and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Objectives of this study were to characterize feed efficiency traits and examine phenotypic relationships with feeding behavior traits in bulls. Performance, feed intake and feeding behavior traits were measured in bulls (n = 5,165) representing 2 breeds (4100 Angus and 952 Red Angus). Intake and feeding behavior traits were measured for 70-d using a GrowSafe system while fed a corn silage based diet (ME = 2.50 Mcal/kg DM). BW was measured at 14-d intervals. Residual feed intake (RFI) was calculated as the difference between actual DMI and that expected from regression of DMI on mid-test BW0.75 (MBW) and ADG, and residual gain (RG) as the difference between actual ADG and that expected from regression of ADG on MBW and DMI. Residual gain and intake (RIG) was computed as the sum of -1 x RFI and RG, both standardized to a variance of 1. Results from the study indicate that RFI was correlated with DMI (r = 0.71, P

Download or read book Examining Mechanisms Contributing to the Biological Variation of Residual Feed Intake in Growing Heifers and Bulls and in Mid gestation Females written by Aimee Hafla and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this study were to characterize residual feed intake (RFI) in growing bulls and heifers and in mid-gestation females to examine relationships with performance, body composition, feeding behavior, digestibility (DMD) and heart rate (HR) and evaluate the impact of RFI on bull fertility and cow forage utilization. Additionally, use of the n-alkane method to predict individual animal variations in intake was investigated. To accomplish these objectives, multiple RFI studies were conducted. In all studies RFI was computed as the difference between actual and expected DMI from linear regression of DMI on mid-test metabolic BW and ADG. To evaluate phenotypic relationships between feed efficiency, scrotal circumference (SC) and semen-quality an experiment was conducted with yearling bulls (N=204). Residual feed intake was not correlated with BW and ADG, but was positively associated with 12th-rib back fat (BF) such that the more efficient bulls were leaner. Bulls with low RFI had similar SC and progressive motility of sperm compared to high-RFI bulls. However percent normal sperm were weakly associated with RFI in a negative manner. To examine phenotypic relationships between heifer postweaning RFI, and performance, efficiency, HR, and DMD of mid-gestation cows, RFI was measured in growing Bonsmara heifers (N=175). Forty-eight heifers with divergent RFI were retained for breeding. Subsequently, intake, performance and feeding behavior was measured on mid-gestation females. Pregnant females classified as having low postweaning RFI continued to consume 22% less feed, spent 25% less time eating, and had 7% lower HR while maintaining similar BW, ADG and body composition compared to high RFI females. A moderate association between RFI in growing heifers and subsequent efficiency of forage utilization in pregnant cows was found. Growing heifers identified as efficient had greater DMD, however DMD in mature cows was similar between RFI groups. The n-alkane method of predicting intake detected differences in intake between divergent RFI groups in mid-gestation females. Results from this study indicate that inclusion of RFI as a component of a multi-trait selection program will improve feed efficiency of growing animals and mid-gestation females with minimal impacts on growth, body composition, and fertility traits.

Download or read book The Relationship Between Residual Feed Intake and Feeding Behavior in Growing Heifers written by Glenda Marie Bingham and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study was to determine if feeding behavior traits are correlated with performance and feed efficiency traits in growing heifers. Individual dry matter intake (DMI) was measured in Brangus heifers (n = 115) fed a roughage-based diet (ME = 2.1 Mcal/kg) for 70 d using Calan gate feeders (6 heifers/pen). Residual feed intake (RFI) was computed as the residuals from linear regression of DMI on mid-test BW0.75 and average daily gain (ADG). Heifers with the highest (n = 18) and lowest (n = 18) RFI were identified for feeding behavior measurements. During days 28 through 56 of the 70-d feeding trial, continuous video recordings were obtained for all heifers. Video images of two sets of four 24-h periods, two weeks apart, were analyzed for the focal animals. All occurrences of feeding were timed and counted per day, and the eight 24-h periods averaged to derive the overall feeding event (FE) and meal duration and frequency for each focal heifer. Total feeding event duration was defined as the total min per day the animal0́9s head was down in the feed bunk. A meal included all visits an animal made to the feed bunk that were separated by less than 5 min. The mean RFI values for the low and high RFI heifers were (mean " SE) - 1.03 and 1.00 " 0.03 kg/d, respectively. Low RFI heifers consumed 21.9% less (P

Download or read book Phenotypic and Genetic Relationships Among Temperament Immune and Carcass Traits in Beef Cattle written by Kerri E. Bates and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cattle temperament has historically influenced selection decisions due to ease of handling. However, temperament may also influence economically relevant traits. The purpose of this study was to investigate relationships between temperament, Bovine Respiratory Disease (BRD) incidence, and resulting carcass merit in feedlot steers. Across a two year period, 2,870 crossbred steers were shipped from a single ranch source to a feedlot. At the time of feedlot placement, as well as at the time of reimplantation, temperament was measured via chute score (CS) and exit velocity (EV). Blood samples were taken upon arrival to the feedlot to determine circulating concentrations of interleukin 8 (IL-8) and cortisol, both of which are involved in immune function. Performance traits, including weight and gains, were measured at feedlot placement (d 0), reimplantation (d 73-100), and again 59 to 70 days later. Recorded carcass data included HCW (HCW), USDA yield grade (YG), marbling score (MS), ribeye area, and lung scores. Phenotypic statistical analysis was performed with SAS statistical software (SAS Inst., Inc., Cary, NC) and genetic parameters were estimated using ASREML (Ver. 3.0, VSN International, Ltd., Hemel Hempstead, UK). The pedigree file included records of 7,177 animals with up to 7 generation of pedigree. Contemporary group (CG, n=11) included initial ranch unit, date of arrival to the feedlot, feedlot pen, and processing dates. Fixed effects included in the model were pre-feedlot entry BRD treatment and CG. Cattle with higher CS at placement subsequently had more BRD incidence (P

Download or read book Energy Expenditure in Growing Heifers with Divergent Residual Feed Intake Phenotypes Effects and Interaction of Metaphylactic Treatment and Temperament on Receiving Steers written by Zachary D. Paddock and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cattle classified as having low residual feed intake (RFI) phenotypes are those that consume less feed than expected based on body weight and growth performance. Mechanisms contributing to the variation in RFI are not fully understood. Previous studies have shown that cattle of divergent RFI phenotypes have different levels of energy expenditures, which are associated with heat increment, basal metabolism, thermoregulation responses, and physical activity. The objectives of this experiment were to characterize residual feed intake (RFI) in growing heifers and to determine if variation in whole-animal energy expenditure contributes to differences in RFI. Brangus heifers (n =120) were individually fed a roughage-based diet (1.93 Mcal ME/kg DM) diet twice daily and feed refusals measured weekly. Heifers were weighed once weekly for 70 d and RFI calculated as the difference between actual and expected DMI from linear regression of DMI on ADG and mid-test BW0.75. Immediately following the 70 d study, oxygen pulse rate (mL O2/heart beat) and 48-h heart rates were measured on 8 high and 8 low RFI heifers to estimate energy expenditure. Daily heart rates and oxygen pulse rates were higher (P

Download or read book Characterization of Residual Feed Intake and Relationships with Performance Carcass and Temperament Traits in Growing Calves written by James Trent Fox and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this study were accomplished with two experiments in growing Bonsmara bulls (N = 68) (experiment 1), and Simmental crossbred calves (N = 132) (experiment 2). Specific objectives for experiment 1 were to characterize residual feed intake (RFI) in growing bulls, and examine relationships between RFI and performance, fertility, temperament and body composition traits. In experiment 2, the objectives were to examine stocker-phase supplementation effects on feedlot feed conversion ratio (FCR) and RFI and to characterize relationships between these feed efficiency traits, and performance and carcass traits in finishing calves. In both experiments, individual feed intakes and BW were measured. Ultrasound technology was used to measure body composition in experiment 1, while actual carcass measurements taken at harvest were used for experiment 2. Experiment 1 demonstrated that temperament affected ADG and DMI, but not FCR or RFI. Residual feed intake was not phenotypically correlated to scrotal circumference or bull fertility traits. Experiments 1 and 2 demonstrated that RFI was independent of ADG and BW, but that there was a tendency (P 0.5 SD above mean RFI). Results from experiment 2 suggest that RFI measured while calves are consuming high-grain diets may be less influenced by previous level of stocker supplementation compared to FCR or residual gain efficiency traits. In summary, RFI was found to be phenotypically independent of growth rate and BW, had no effect on bull fertility or temperament traits, and was less impacted by previous plane of nutrition compared to FCR.

Download or read book Residual Feed Intake in Beef Cattle written by Steven Guercio and published by . This book was released on 2003 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biology of Domestic Animals written by Colin G. Scanes and published by CRC Press. This book was released on 2017-09-01 with total page 509 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is increasing interest in the biology of domestic animals ranging from genomics, transcriptomics, metabolomics, nutritional physiology, and systems biology. This book touches on all of these, with a particular focus on topics such as domestic animals as comparative models to humans, molecular regulation of growth, metabolic efficiency, reproduction, and the impact of stress on growth and development. The book concludes with a discussion on the current and future directions for researchers.

Download or read book Guidelines for Uniform Beef Improvement Programs written by Dixon D. Hubbard and published by . This book was released on 1981 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: