scholarly journals The influence of proportion of Simmentaler breeding in a multibreed synthetic beef cattle population on preweaning growth traits

Author(s):  
S.J. Schoeman ◽  
G.F. Jordaan ◽  
H. Skrypzeck
1991 ◽  
Vol 71 (2) ◽  
pp. 279-285 ◽  
Author(s):  
M. F. Liu ◽  
M. Makarechian ◽  
R. T. Berg

Genetic and phenotypic parameters of growth traits from birth to 1 year of age were compared in a multibreed Beef Synthetic (SY) and a purebred Hereford (HE) population managed together under the same environmental conditions and selected for growth rate from 1961 to 1979. Growth traits studied were birth weight, preweaning and postweaning gains. Records of 2077 calves of 70 HE and 100 SY paternal half-sib families were used for analysis. Except for birth weight, phenotypic variances of growth traits were similar for the synthetic (SY) and purebred (HE) populations, but genetic variances were larger in SY than in HE for all growth traits except postweaning gain in males. The coefficients of variation were comparable for all the traits studied in the two populations, indicating that phenotypic variations in the multibreed population and the purebred population were similar. Key words: Variance components, heritability, beef cattle


2020 ◽  
Author(s):  
Guoyao Zhao ◽  
Tianliu Zhang ◽  
Yuqiang Liu ◽  
Zezhao Wang ◽  
Lei Xu ◽  
...  

Abstract Background: Runs of homozygosity (ROH) are continuous homozygous regions that generally exist in the DNA sequence of diploid organisms. Identifications of regions of the genome lead to reduction in performance can provide valuable insight into the genetic architecture of complex traits. Here, we evaluated genome-wide patterns of homozygosity and their association with growth traits in a commercial beef cattle population.Results: We identified a total of 29,271 ROH segments with an average number of 63.36 and an average length of 0.98 Mb in this commercial beef cattle population, representing ~2.53% (~63.36Mb) of the genome. To evaluate the enrichment of ROH across genomes, we initially identified 280 ROH regions by merging ROH events identified across all individuals. Of these, nine regions were significantly associated with six growth phenotype traits (body height, chest circumference, fat coverage, backfat thickness, ribeye area, carcass length; P<0.01), which contain 187 candidate genes. Furthermore, we found 26 consensus ROH regions with frequencies exceeding 10%, and several of these consensus overlapped with QTLs which are associated with weight gain, calving difficulty and stillbirth. To precisely locate locus within each ROH for every studied trait, we further utilized loci-based methods for association analysis among these identified regions. Totally, we obtained 9,360 loci within ROH, and 1,631 loci displaying significant association (P<0.01) for eight traits. In addition, we found that 67 genes embedded with homozygous loci. Several identified candidate genes, including EBF2, SLC20A2, SH3BGRL2, HMGA1 and ACSL1, were related to growth traits.Conclusions: This study assessed genome-wide autozygosity pattern and inbreeding level in a commercial beef cattle population. Our study identified many candidate regions and genes with ROH for growth traits in beef cattle, which can provide important insights into investigating homozygosity across genome in other farm animals. Our findings may further be unitized to assist the design of selection mating strategy.


2019 ◽  
Vol 3 (2) ◽  
pp. 172
Author(s):  
Sri - Purwanti ◽  
Syamsuddin Nompo ◽  
Laily Agustina ◽  
Muh. Nur Hidayat

The activities conducted in Maros regency Tanralili district Purnakarya village in chickens and beef cattle groups Cedde Jaya. The main source of livestock feed cows during the dry season are dry forage, rice straw, corn straw and hay crops of nuts which happened to be planted at the time of drought. Besides, leaf  Gamal is also a main feed in dry  season. Number of cattle per family ownership only 2-3  head extensively maintained. Range chicken as well as extensive maintenance, ownership on average 2-5 chicken each household group.  To increase the productivity of cattle, the team provides counseling, coaching, training and mentoring as well as providing some main of facilities such as cattle shed, biogas digester, planting banana. Results are expected in the presence of  activities is the avaibility of green forage mainly during the dry season, so that the cattle population will increase, the biogas as a fuel  alternative to kerosin and LPG gas, liquid and solid fertilizer from biogas by-product process, the increasing population of chicken qualified (meat and eggs as well as the day old chick).  Besides the problem of production is also done on the farm management. The activities is expected that will increase the incomes of farmers further improve the welfare of Maros regency. For the sustainability of the program it is necessary supervision and guidance are routinely performed by the related department along with the college.


2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Emmanuel A. Lozada-Soto ◽  
Christian Maltecca ◽  
Duc Lu ◽  
Stephen Miller ◽  
John B. Cole ◽  
...  

Abstract Background While the adoption of genomic evaluations in livestock has increased genetic gain rates, its effects on genetic diversity and accumulation of inbreeding have raised concerns in cattle populations. Increased inbreeding may affect fitness and decrease the mean performance for economically important traits, such as fertility and growth in beef cattle, with the age of inbreeding having a possible effect on the magnitude of inbreeding depression. The purpose of this study was to determine changes in genetic diversity as a result of the implementation of genomic selection in Angus cattle and quantify potential inbreeding depression effects of total pedigree and genomic inbreeding, and also to investigate the impact of recent and ancient inbreeding. Results We found that the yearly rate of inbreeding accumulation remained similar in sires and decreased significantly in dams since the implementation of genomic selection. Other measures such as effective population size and the effective number of chromosome segments show little evidence of a detrimental effect of using genomic selection strategies on the genetic diversity of beef cattle. We also quantified pedigree and genomic inbreeding depression for fertility and growth. While inbreeding did not affect fertility, an increase in pedigree or genomic inbreeding was associated with decreased birth weight, weaning weight, and post-weaning gain in both sexes. We also measured the impact of the age of inbreeding and found that recent inbreeding had a larger depressive effect on growth than ancient inbreeding. Conclusions In this study, we sought to quantify and understand the possible consequences of genomic selection on the genetic diversity of American Angus cattle. In both sires and dams, we found that, generally, genomic selection resulted in decreased rates of pedigree and genomic inbreeding accumulation and increased or sustained effective population sizes and number of independently segregating chromosome segments. We also found significant depressive effects of inbreeding accumulation on economically important growth traits, particularly with genomic and recent inbreeding.


2011 ◽  
Vol 91 (2) ◽  
pp. 305-321 ◽  
Author(s):  
Aklilu Alemu ◽  
K. H. Ominski ◽  
E. Kebreab

Alemu, A. W., Ominski, K. H. and Kebreab, E. 2011. Estimation of enteric methane emissions trends (1990–2008) from Manitoba beef cattle using empirical and mechanistic models. Can. J. Anim. Sci. 91: 305–321. The objective of this study was to estimate and assess trends in enteric methane (CH4) emissions from the Manitoba beef cattle population from the base year of 1990 to 2008 using mathematical models. Two empirical (statistical) models: Intergovernmental Panel on Climate Change (IPCC) Tier 2 and a nonlinear equation (Ellis), and two dynamic mechanistic models: MOLLY (v3) and COWPOLL were used. Beef cattle in Manitoba were categorized in to 29 distinct subcategories based on management practice, physiological status, gender, age and production environment. Data on animal performance, feeding and management practices and feed composition were collected from the literature as well as from provincial and national sources. Estimates of total enteric CH4 production from the Manitoba beef cattle population varied between 0.9 and 2.4 Mt CO2 eq. from 1990 to 2008. Regardless of the type of models used, average CH4 emissions for 2008 were estimated to be 45.2% higher than 1990 levels. More specifically, CH4 emissions tended to increase between 1990 and 1996. Emissions were relatively stable between 1996 and 2002, increased between 2003 and 2005, but declined by 13.2% between 2005 and 2008, following the same trend as that observed in the beef cattle population. Models varied in their estimates of CH4 conversion rate (Ym, percent gross energy intake), emission factor (kg CH4 head−1 yr−1) and CH4 production. Total CH4 production estimates ranged from 1.2 to 2.0 Mt CO2 eq. for IPCC Tier 2, from 0.9 to 1.5 Mt CO2 eq. for Ellis, from 1.3 to 2.1 Mt CO2 eq. for COWPOLL and from 1.5 to 2.4 Mt CO2 eq. for MOLLY. The results indicate that enteric CH4 estimates and emission trends in Manitoba were influenced by the type of model and beef cattle population. As such, it is necessary to use appropriate models for reliable estimates for enteric CH4 inventory. A more robust approach may be to integrate different models by using mechanistic models to estimate regional Ym values, which may then be used as input for the IPCC Tier 2 model.


1993 ◽  
Vol 34 (1-2) ◽  
pp. 57-70 ◽  
Author(s):  
D.F. Waldron ◽  
C.A. Morris ◽  
R.L. Baker ◽  
D.L. Johnson

Sign in / Sign up

Export Citation Format

Share Document