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Sequencing of the Cattle Genome Toward Finding Ways to Increase Feed Efficiency of Cattle
Woonsu Kim,Seongwon Seo
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.3223.3227
Abstract: Considering the continuous increase in feed cost, the greatest part of the cattle production cost and the growth of environmental concerns, improvement of feed efficiency has potentials not only for increasing profits for cattle producers but also for decreasing environmental impacts of cattle production. The recent sequencing of the cattle genome provides the first opportunity to explore the relationship between genetic and feed efficiency of cattle. This short review aims to describe recent findings from the sequencing analysis of the cattle genome and to illustrate how this new information can be applied increase feed efficiency of cattle.
Residual feed intake in beef cattle
Arthur, J P.F.;Herd, R.M.;
Revista Brasileira de Zootecnia , 2008, DOI: 10.1590/S1516-35982008001300031
Abstract: 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 lower the value the more efficient the animal is. this paper examines the current state of knowledge on rfi. available information indicates that postweaning rfi is moderately heritable, and that selection for low rfi will result in progeny that consume less feed for the same level of production as progeny of high rfi cattle. under ad libitum feeding, rfi is phenotypically independent of growth traits. there is a weak genetic relationship between rfi and fatness but additional studies are needed to assess the magnitude of this relationship in different breeds, sexes, ages and feeding regimes. residual feed intake is believed to represent inherent variation in basic metabolic processes which determine efficiency. economic analyses of genetic improvement schemes that incorporate testing of individuals for rfi have yielded substantial economic benefits over and above existing schemes that do not include rfi testing. selection for low rfi has an additional benefit of reducing greenhouse gas emissions by cattle.
Modeling cadmium in the feed chain and cattle organs  [PDF]
van der Fels-Klerx, I.,R?mkens, P.,Franz, E.,van Raamsdonk, L.
Biotechnologie, Agronomie, Société et Environnement , 2011,
Abstract: The objectives of this study were to estimate cadmium contamination levels in different scenarios related to soil characteristics and assumptions regarding cadmium accumulation in the animal tissues, using quantitative supply chain modeling. The model takes into account soil cadmium levels, soil pH, soil-to-plant transfer, animal consumption patterns, and transfer into animal organs (liver and kidneys). The model was applied to cattle up to the age of six years which were fed roughage (maize and grass) and compound feed. Cadmium content in roughage and cadmium intake by cattle were calculated for six different (soil) scenarios varying in soil cadmium levels and soil pH. For each of the six scenarios, the carry-over of cadmium from intake into the cattle organs was estimated applying two model assumptions, i.e., linear accumulation and a steady state situation. The results showed that only in the most extreme soil scenario (cadmium level 2.5 mg.kg-1, pH 4.5), cadmium exceeded the EC maximum tolerated level in roughage. Assuming linear accumulation, cadmium levels in organs of cattle up to six years of age, ranged from 0.37-4.03 mg.kg-1 of fresh weight for kidneys and from 0.07 to 0.77 mg.kg-1 of fresh weight for livers. The maximum tolerated levels in one or both organs were exceeded in several scenarios. When considering organ excretion of cadmium, internal cadmium levels in organs were approximately one order of magnitude lower as compared to the results of the linear accumulation model. In this case only in the most extreme soil scenario, the maximum tolerated level in the kidney was exceeded. It was concluded that the difference between the two assumptions (linear model versus a steady state situation to estimate cadmium carry-over in cattle) is negligible in the animal's first five years of life, but will become relevant at higher ages. For the current case, the linear approach is a good descriptor for worst case situations. Furthermore, this study showed that quantitative supply chain modeling is an effective tool in assessing whether or not a specific combination of soil properties would lead to unacceptable contaminant levels in feedstuffs and animal products in the view of animal and human health.
Climate Change Concern to Cattle Feed in Bangladesh
Ferdous Ahmed,Abul Quasem Al-Amin,Gazi Mahabubul Alam,Che Hashim Hassan
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.1946.1953
Abstract: This research focuses the climate change concerns for livestock feeding management in Bangladesh as it causes strange behavior and variation of cattle diets and feed shortages in the last two decades. It is obvious from the recent literature that Bangladesh is one of the most climate change vulnerable country of the world to climate change. It causes cattle feed shortages, modification in major production of yields, alteration in a variety composition of rangeland and edifying variety of cattle feed setback. The climate change concern to cattle feed in Bangladesh are now real and need to overcome the problems by the subject to current research effort and value. Therefore, in this study specific justification is used to figure out the factors that are responsible and discussed the national lacking, required action, limitation and possible alternative options. Moreover, following on the national lacking, required action and limitations, this study incorporated a framework of approach and strategies for the policy makers of Bangladesh.
Feed efficiency of Nellore cattle selected for postweaning weight
Castilhos, André Michel de;Branco, Renata Helena;Corvino, Tatiana Lucila Sobrinho;Razook, Alexander George;Bonilha, Sarah Figueiredo Martins;Figueiredo, Leopoldo Andrade de;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010001100023
Abstract: two nellore herds were compared, one selected for greater postweaning weight and the other, control, selected for average postweaning weight, to evaluate the effects of 29 years of selection on feed efficiency. sixty nellore males (41 selected and 19 control) averaging 205 kg and 267 days of age were evaluated in individual pens during performance test. performance and dry matter intake were used to determine the following feed efficiency traits: feed conversion; residual feed intake; residual gain; partial growth efficiency; relative growth rate and kleiber ratio. after the 112-day experimental period, control animals showed lower body weight when compared to selected animals, however, they did not differ for dry matter intake (% of body weight), rib-eye area and fat thickness at the 12th rib subcutaneous region and on the rump region. dry matter intake (kg/day) and average daily weight gain from selected animals were, respectively, 19.4% and 26.4% higher than the control ones. the highest average daily weight gain by selected animals promoted significant improvement, around 6%, on feed conversion; 70 g/day on residual gain; and 17% on kleiber rate. the other feed efficiency traits (residual feed intake, partial growth efficiency and relative growth rate) did not differ between herds. the 29-year selection for post-weaning weight did not affect feed efficiency of nellore cattle.
Availability Optimization for Screw Plant Based on Genetic Algorithm
Deepika Garg,,Kuldeep Kumar,Meenu
International Journal of Engineering Science and Technology , 2010,
Abstract: This paper deals with availability optimization for screw plant using genetic algorithm. Screw plant has four main subsystems, out of theses four subsystems, two subsystems are provided with cold stand byalternativeConsidering the exponential distribution for the probable failures and repairs, Mathematical formulation of the problem is done using probabilistic approach and differential equations are developed using Markov birth – death Process. These equations are then solved using normalizing conditions so as to determine the steady state availability of the concern plant.Then further genetic algorithm is applied to find optimal value for availability of concern plant and corresponding to this optimum value of availability, value of failure/repair rates of all subsystems of concern plant are calculated.
Impact of reduced marker set estimation of genomic relationship matrices on genomic selection for feed efficiency in Angus cattle
Megan M Rolf, Jeremy F Taylor, Robert D Schnabel, Stephanie D McKay, Matthew C McClure, Sally L Northcutt, Monty S Kerley, Robert L Weaber
BMC Genetics , 2010, DOI: 10.1186/1471-2156-11-24
Abstract: Results were compared to estimates produced from pedigree-based mixed model analysis of 862 Angus steers with 34,864 identified paternal relatives but no female ancestors. Estimates of additive genetic variance and breeding value accuracies were similar for AFI and RFI using the numerator and genomic relationship matrices despite fewer animals in the genomic analysis. Bootstrap analyses indicated that 2,500-10,000 markers are required for robust estimation of genomic relationship matrices in cattle.This research shows that breeding values and their accuracies may be estimated for commercially important sires for traits recorded in experimental populations without the need for pedigree data to establish identity by descent between members of the commercial and experimental populations when at least 2,500 SNPs are available for the generation of a genomic relationship matrix.The advent of national genetic evaluation in beef cattle was made possible by the formulation of best linear unbiased prediction (BLUP) via the mixed model equations [1] and most livestock species now use BLUP for the evaluation of additive genetic merit and selection of parents to produce the next generation of progeny. However, most traits for which estimated breeding values or expected progeny differences (EPDs) are computed measure animal outputs rather than inputs. Because of the increased cost of production system inputs, interest has recently been stimulated for the development of efficient methods for producing phenotypes and EPDs for the efficiency of feed utilization. Feed costs in calf feeding and yearling finishing systems account for approximately 66% and 77% of total costs, respectively [2] and while increasing growth rate by 10% has been estimated to increase profitability by 18%, increasing the efficiency of growth of feedlot cattle by 10% is expected to increase profitability by 43% [3]. Other studies have suggested that increasing the feed efficiency of feedlot cattle has seven t
Efficiency of feed nitrogen conversion in dairy cattle herds
Davide Biagini,Carla Lazzaroni
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2009.s2.265
Abstract: To evaluate the effect of feasible strategies to mitigate dairy herd’s environmental impact in a homogeneous area, the actual level of N excretion and conversion efficiency was determined in fifteen farms located in the North-West of Italy. Main factors affecting N efficiency (feeds consumption and composition, live weight, productions, milk urea and reproductive indexes) were recorded for cows (C), heifers (H, 12-24 months) and young heifers (YH, 6-12 months). N requirements, retention, excretion and efficiency were calculated. N excretion was respectively 131.39, 60.88 and 47.49 kg/year/head for C, H and YH and 14.07 kg/year per litre of milk in C. Feed N conversion efficiency was respectively 28.40, 8.90 and 6.64 in C, H and YH. In the studied farms N efficiency could be increased acting on the most important factors affecting N utilisation, so reducing the environmental impact of dairy cattle.
Forage intake and botanical composition of feed for cattle fed Brachiaria/legume mixtures
Macedo, Robert;Tarré, Ricardo Martinez;Ferreira, Elvino;Rezende, Claudia de Paula;Pereira, José Marques;Cadisch, Georg;Rouws, Janaina Ribeiro Costa;Alves, Bruno José Rodrigues;Urquiaga, Segundo;Boddey, Robert Michael;
Scientia Agricola , 2010, DOI: 10.1590/S0103-90162010000400002
Abstract: a key contribution to study the cycling of nutrients in soil/plant/animal systems is the evaluation of the consumption of forage and their nutrients by cattle. the objective of this study was to test techniques to evaluate faecal production, in vitro digestibility, forage consumption and the proportion of legume in the acquired diet. five zebu steer calves were confined and fed five diets of different combinations of brachiaria dictyoneura and desmodium ovalifolium. all quantities of faeces were collected per animal and these values were found to compare favourably with those derived from using the chromium oxide technique. in vitro digestibility ranged from 7 to 10% higher than the actual in vivo digestibility. faecal samples from steers fed with diets with 25% or more of grass in the mixture were found to be depleted in δ13c between 1.7 and 2.1‰, but no depletion was observed when the diet was 100% d. ovalifolium. there was a positive linear regression (r2 = 0.97***) of the δ13c of the diet with the δ13c of faeces, but if the acquired diet contained a very high proportion of legume, the legume content could be underestimated by as much as 10%. none of the internal indicators, such as lignin or ash content of the diets, were useful to predict feed intake, but the chromium oxide external indicator performed satisfactorily. the 13c analysis of the faeces was an effective predictor of the proportion of the legume in the consumed diet.
Physical Characteristics of Pressed Complete Feed for Dairy Cattle  [cached]
M. Munasik,C. Imam Sutrisno,Syaiful Anwar,Caribu Hadi Prayitno
International Journal of Science and Engineering , 2013, DOI: 10.12777/ijse.v4i2.4566
Abstract: The study was aimed to evaluate the physical characteristics of the pressed complete feed in the forms of cube, cylinder and ball. The study was conducted to get a complete feed of dairy cows that can be developed commercially. The evaluation was done on a physical test : bulkiness, hardness and hygroscopic properties of pressed complete feeds. The results of this research showed that the bulkiness of pressed complete feed in the forms cubes, cylinders and balls were between 0.20 up to 0.48 liter/kg; the hardness of pressed complete feed, cylinders and balls were 3 lbs up to 14 lbs; the hygroscopic factor of pressed complete feed in the forms cubes, cylinders and balls were around 1.10% up to 9.69%. The pressed complete feed in the forms of cube and cylinder are better than the form of ball in physical characteristics. doi: 10.12777/ijse.4.2.2013.61-65
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