scholarly journals Thesis Abstract Study of different structures of additive genetic groups to increase the efficiency of genetic selection in beef cattle

2014 ◽  
Vol 13 (1) ◽  
pp. 115-116
Author(s):  
G.A. Oliveira Junior
Keyword(s):  
Beef Cattle ◽  
Genetic Selection ◽  
Genetic Groups

scholarly journals Pearl millet grain for beef cattle in crop-livestock integration system: intake and digestibility

2017 ◽  
Vol 38 (3) ◽  
pp. 1471 ◽  
Author(s):  
Marcell Patachi Alonso ◽  
Eduardo Henrique Bevitori Kling de Moraes ◽  
Dalton Henrique Pereira ◽  
Douglas Dos Santos Pina ◽  
Mircéia Angele Mombach ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Pearl Millet ◽  
Brachiaria Brizantha ◽  
Integration System ◽  
Genetic Groups ◽  
Protein Energy ◽  
Dietary Concentration ◽  
Maize Grain ◽  
Energy Supplements ◽  
Different Levels

The present study aimed to evaluate the nutritional parameters (intake and digestibility) of beef cattle in two genetic groups fed protein-energy supplements formulated by different levels of replacement of maize with pearl millet grain during the dry season. Sixty-four uncastrated young bulls, with an average age of 20 months and an initial body weight of 388 ± 26 kg, were included in the study. The experimental area consisted of four paddocks approximately 4.7 ha in size, composed of Brachiaria brizantha ‘Marandu’ within a crop-livestock integration system. The study was based on a completely randomized factorial design (2×4). Two genetic groups (Crossbred and Nellore) and the effects of replacement of maize with pearl millet grain at 0%, 33%, 66%, and 100% in the supplement formulations were assessed. No significant effects were observed in the genetic groups and with the replacement of maize with pearl millet grain, as well as in the pasture total dry matter (DM) and nutrients intake, or the coefficients of total digestibility of nutrients. The dietary concentration of digested organic matter was not influenced by the replacement levels of pearl millet grain, with values of 514.88, 515.76, 516.01, and 515.98 g kg-1 of DM recorded for the 0%, 33%, 66%, and 100% replacement levels, respectively. Therefore, pearl millet grain can be utilized as a partial or total substitute for maize grain as the energetic ingredient in concentrated supplements for Nellore and crossbred beef cattle in pastures managed in crop-livestock integration systems.

scholarly journals Genetic selection for temperament traits in dairy and beef cattle

2014 ◽  
Vol 5 ◽  
Author(s):  
Marie J. Haskell ◽  
Geoff Simm ◽  
Simon P. Turner
Keyword(s):  
Beef Cattle ◽  
Genetic Selection ◽  
Selection For ◽  
Temperament Traits

scholarly journals Genetic group and heterosis on morphometric measurements during the growth of male beef cattle

2016 ◽  
Vol 37 (4Supl1) ◽  
pp. 2759
Author(s):  
Ricardo Zambarda Vaz ◽  
João Restle ◽  
Paulo Santana Pacheco ◽  
Fabiano Nunes Vaz ◽  
Luiz Danilo Muehlmann ◽  
...  
Keyword(s):  
Body Weight ◽  
Beef Cattle ◽  
First Generation ◽  
Second Generation ◽  
Genetic Group ◽  
Body Measurements ◽  
Morphometric Measurements ◽  
Genetic Groups ◽  
Body Development

In the present study, the effects of genetic group and heterosis on body measurements of purebreds (Charolais - C and Nellore - N), first-generation crossbreds (G1) (1/2C1/2N and 1/2N1/2C), and second-generation crossbreds (G2) (3/4C1/4N and 3/4N1/4C) males from rotational crossbreeding were evaluated at 8, 12, 18, and 24 months of age. Among the purebreds, the Nellore displayed greater rump height than the Charolais. The Charolais had greater thoracic perimeter than the Nellore, however this difference decreased gradually with advancing age, being equal between the two genetic groups at 24 months. For width of the rump, ischial opening and thoracic perimeter crossbred animals showed higher values than the purebred animals at all ages, but less pronounced at eight months of age. For all morphometric measurements, with exception of rump height, the differences of crossbreds males in relation to the purebreds, were more evident in relation to the Nellore. Heterosis was significant for morphometric measurements in male beef cattle. Morphometric measurements showed high correlation with each other and with body weight, thereby indicating that they are good indicators of body development.

Evaluation of advanced industry breeding schemes for Australian beef cattle. I. Method of evaluation and analysis for an example population structure

1994 ◽  
Vol 45 (8) ◽  
pp. 1641 ◽  
Author(s):  
G Nitter ◽  
HU Graser ◽  
SA Barwick
Keyword(s):  
Beef Cattle ◽  
Net Present Value ◽  
Growth Traits ◽  
Genetic Selection ◽  
Present Value ◽  
Technical Parameters ◽  
Breeding Objective ◽  
Breeding Schemes ◽  
Selection Gene ◽  
Method Of Evaluation

A method is presented for evaluating industry breeding schemes for Australian beef cattle. Multitrait selection is considered. The criteria of evaluation are the annual genetic gains in the breeding objective and its component traits, and the net present value of the return from investment in the scheme. The main methods employed by the PC computer program ZPLAN, developed to facilitate such evaluations, are described and are applied to an example population. A deterministic approach is taken to the prediction of annual genetic gain. Various selection groups are defined in the population, each with particular information sources for index selection, and allowing also for two-stage selection. Gene flow methods are applied to assess the discounted return from investment in one round of selection over a defined investment period. The associated fixed and variable costs are calculated, and used to derive the net present value, or profit, from the selection. An example population with a breeding unit of 10000 cows, supplying bulls to a total population of 200000 cows, is envisaged. Seventy percent of the cows in commercial herds are assumed to be mated by bulls derived from the breeding unit. Genetic and biological/technical parameters required by the program are presented. Criteria considered to be available for use in selection are weights at birth and at 200, 400 and 600 days of age. Results are given for individual selection groups and for the whole population. The annual genetic response in the breeding objective ($1.43) comprised $2.21 gain in growth traits (sale weight direct and maternal), $0.37 gain in reproduction traits (cow survival and weaning rates and bull fertility), $0.06 loss in carcass traits (dressing and saleable meat percentages and fat depth), a $1.00 increase in the cost of maintaining cows and a $0.09 loss for increased calving difficulty. The return, cost and profit per cow in the population from one round of genetic selection using the available growth measures was $8.14, $1.34 and $6.81, respectively.

scholarly journals Artificial infestation of Boophilus microplus in beef cattle heifers of four genetic groups

2007 ◽  
Vol 30 (4) ◽  
pp. 1150-1155 ◽  
Author(s):  
Ana Mary da Silva ◽  
Maurício Mello de Alencar ◽  
Luciana Correia de Almeida Regitano ◽  
Márcia Cristina de Sena Oliveira ◽  
Waldomiro Barioni Júnior
Keyword(s):  
Beef Cattle ◽  
Boophilus Microplus ◽  
Genetic Groups ◽  
Artificial Infestation

scholarly journals Genetic selection strategies to improve longevity in Chianina beef cattle

2006 ◽  
Vol 5 (2) ◽  
pp. 117-127 ◽  
Author(s):  
Flavio Forabosco ◽  
Paul Boettcher ◽  
Riccardo Bozzi ◽  
Francesco Filippini ◽  
Piter Bijma
Keyword(s):  
Beef Cattle ◽  
Genetic Selection ◽  
Selection Strategies

Resistance of beef cattle of two genetic groups to ectoparasites and gastrointestinal nematodes in the state of São Paulo, Brazil

2013 ◽  
Vol 197 (1-2) ◽  
pp. 168-175 ◽  
Author(s):  
M.C.S. Oliveira ◽  
M.M. Alencar ◽  
R. Giglioti ◽  
M.C.D. Beraldo ◽  
F.F. Aníbal ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Gastrointestinal Nematodes ◽  
Sao Paulo ◽  
The State ◽  
São Paulo ◽  
Genetic Groups

scholarly journals Looking Ahead: Applying new Genomic Technologies to Accelerate Genetic Improvement in Beef Cattle

Ceiba ◽  
2016 ◽  
Vol 54 (1) ◽  
pp. 41-49
Author(s):  
Angela Cánovas
Keyword(s):  
Beef Cattle ◽  
Complex Traits ◽  
Gene Networks ◽  
Genetic Selection ◽  
Breeding Values ◽  
Regulatory Pathways ◽  
Reproductive Management ◽  
Genomic Technologies ◽  
Selection Decisions ◽  
Order Of Magnitude

In recent years, producers have combined the use of phenotypic appraisal and the estimation of breeding values (PTA or EPD) to make genetic selection decisions in beef and dairy cattle that have resulted in a steady genetic gain of 2% per year. However, the most extensive application of genomics has occurred in dairy with the estimation of molecular breeding values that has increased selection efficiency to a much higher order of magnitude. Despite a growing molecular and physiological understanding of complex traits, little is known about the genes determining the traits and their precise function, and a significant unexplained source of variation of phenotypes remains in livestock. Within this context, a more complete understanding of the genes and regulatory pathways and networks involved in economically important traits (i.e. feed efficiency and methane emissions, meat quality and carcass traits) in beef cattle will provide knowledge to help improve genetic selection and reproductive management. Therefore, high throughput -OMICS technology (i.e., transcriptomics, metagenomics, metabolomics, as well as epigenetics and gene networks amongst several others), will complement these tools and further advance identification of functional genes within a systems biology approach.

scholarly journals Diet and breed alter community structures of rumen protozoa in cattle subjected to different feeding systems

2019 ◽  
Vol 40 (2) ◽  
pp. 909
Author(s):  
Cândida Camila dos Reis ◽  
Emilyn Midori Maeda ◽  
Franciane Cedrola ◽  
Elias Nunes Martins ◽  
Fabiana Matielo De Paula ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Principal Component ◽  
Rumen Protozoa ◽  
Analysis Methodology ◽  
Genetic Groups ◽  
The Family ◽  
Counting Chamber ◽  
Microscopy Data ◽  
Optic Microscopy ◽  
Feeding Systems

The objective were to identify and quantify the rumen protozoa from two genetic groups of beef cattle (Nellore and crossbred European beef cattle) subjected to three feeding systems (pasture, pasture supplement, and confined). Samples of rumen contents were obtained from the center of the ruminal mass after slaughter. Quantification and identification of rumen protozoa were performed with a Sedgewick-Rafter counting chamber by optic microscopy. Data were analyzed using general linear analysis methodology with a Poisson distribution (1 %). In addition, the data underwent of Analisys Principal Component. A effect on ruminal protozoa was observed for the diets and breeds analyzed. Was identified 14 genera, among which Entodinium was predominant in all animals analyzed. Ciliates belonging to Entodiniomorphida, Eodinium, Epidinium, Eremoplastron, Eudiplodinium, Metadinium, and Ostracodinium showed highest density in Nellore animals when compared with the crossbreed, Nellore × European. Larger numbers of protozoa from the family Isotrichidae (Dasytricha and Isotricha) were observed in animals maintained by pasture or pasture supplement feeding. According to the kind of feeding, those fed exclusively with pasture had a greater diversity of ciliates in comparison to those restricted to, or supplemented with pasture. In one animal, the occurrence of ciliates belonging to the genus Buetschlia, was observed (prevalence of 1.66 %), which is one of only a few records of this genus in ruminants.

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