scholarly journals Genetic control of methane emission, feed efficiency and metagenomics in dairy cattle

2018 ◽  
Author(s):  
Gareth Frank Difford
2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 271-272
Author(s):  
Hinayah Oliveira ◽  
Flavio Schenkel ◽  
Caeli M R Richardson ◽  
Filippo Miglior ◽  
Luiz Brito

Abstract Over 60% of the production costs in dairy cattle are related to feeding. Genetic selection for improved feed efficiency (FE) is a very promising alternative to reduce feeding costs, increase the industry profitability, and reduce the industry environmental footprints. The success of genetic selection relies in part on the heritability (h2) of the indicator traits included in the breeding programs. Several studies have reported h2 estimates for different FE indicator traits, with a broad range of estimates. To obtain more consistent h2 estimates across studies and populations, we performed a meta-analysis of published h2 estimates using four different groups of FE indicator traits commonly used in dairy cattle: 1) energy intake (EI); 2) residual feed intake (RFI); 3) feed (dry-matter) intake (FI); and 4) feed conversion efficiency (FCE). A comprehensive literature review identified 148 h2 estimates across 39 scientific papers from 13 different countries, published between 1991 and 2019. Thereafter, a meta-analysis based on random-effects model was used to summarize and address the variability of the parameter estimates. Our study confirmed that FE indicator traits in dairy cattle are under moderate genetic control. The h2 estimates were 0.18±0.02, 0.19±0.02, 0.29±0.01, and 0.19±0.03 for EI, RFI, FI, and FCE, respectively. In addition, our findings showed that h2 estimates for FE indicator traits in different studies have significant heterogeneity (I2 index estimated for EI, RFI, FI and FCE was 80.5%, 59.8%, 81.7%, and 55.7%, respectively). Among the possible sources of variation that contributed to the heterogeneity across studies are country, type of housing, life stage, and diet. The results reported here summarize the overall level of genetic control of FE in dairy cattle, which are useful for genetic evaluations when reliable h2 estimates for FE are not available in the studied dairy cattle population.


2021 ◽  
Author(s):  
Bruno G.N. Andrade ◽  
Haithem Afli ◽  
Flavia A. Bressani ◽  
Rafael R. C. Cuadrat ◽  
Priscila S. N. de Oliveira ◽  
...  

Abstract Background: The impact of extreme changes in weather patterns in the economy and human welfare are some of the biggest challenges that our civilization is facing. From the anthropogenic activities that contribute to climate change, reducing the impact of farming activities is a priority, since it is responsible for up to 18% of greenhouse gases linked to such activities. To this end, we tested if the ruminal and fecal microbiome components of 52 Brazilian Nelore bulls, belonging to two treatment groups based on the feed intervention, conventional and by-products based diet, could be used in the future as biomarkers for methane emission and feed efficiency in bovine.Results: We identified a total of 5,693 Amplicon Sequence Variants (ASVs) in the Nelore bulls microbiomes. Differential abundance (DA) analysis with the ANCOM approach identified 30 bacterial and 15 archaea ASVs as DA among treatment groups. Association analysis using Maaslin2 and Mixed Linear Models indicated that bacterial ASVs are linked to the residual methane emission (RCH4) and Residual Feed Intake (RFI) phenotypes, contributing to the host’s phenotypic variation, suggesting their potential as targets for interventions and/or biomarkers.Conclusion: Feed composition induced significant differences in abundance and richness of ruminal and fecal microbial populations. The diet based on industrial byproducts applied to our treatment groups influenced the microbiome diversity of bacteria and archaea, but not of protozoa. Different ASVs were associated with RCH4 emission and RFI in both ruminal and fecal microbiomes. While ruminal ASVs are expected to directly influence RCH4 emission and RFI, the relation of fecal taxa, such as Alistipes and Rikenellaceae (gut group RC9), with these traits might also be associated with host health due to their link to anti-inflammatory compounds, and these have the potential to be used as accessible biomarkers for these complex phenotypes.


1992 ◽  
Vol 72 (2) ◽  
pp. 227-236 ◽  
Author(s):  
S. Wang ◽  
G. L. Roy ◽  
A. J. Lee ◽  
A. J. McAllister ◽  
T. R. Batra ◽  
...  

Early first lactation data from 2230 cows of five research herds of Agriculture Canada were used to study the interactions of genetic line by concentrate level, and sire by concentrate level and to estimate breeding values of sires. The genetic lines were defined as Holstein (H), Ayrshire (A), and H × A or A × H (C). The interactions of sire by concentrate level were studied separately using progeny of five different mating groups: G1, H sires mated to H cows; G2, H sires mated to H, A and C cows; G3, A sires mated to A cows; G4, A sires mated to H, A and C cows; and G5, C sires mated to C cows. The interactions of genetic line by concentrate were significant (P < 0.05) for 56- to 112-d milk yield (MY112), corrected 56-to 112-d milk yield (CMY112) and feed efficiency (EFMY112 = MY112/TDN consumption). H and C cows produced more milk and were more efficient than A cows when fed high levels of concentrate. The H cattle possess a greater capacity to convert the concentrate into milk, while A cattle reach maximum milk production earlier than H cattle. The interactions of sire by concentrate were statistically significant for MY112, EFMY112 and CMY112 in G1 (P < 0.01), and G2 (P < 0.01). The breeding values of sires for MY112 were estimated using BLUP for all of the H line (BLUP-T), for half of the population consuming low amounts of concentrate (BLUP-L) and for the other half consuming high amounts (BLUP-H). A significant reranking of sires was found among the three groups. Key words: Genotype × environment interaction, milk production, efficiency, breeding value, dairy cattle


2016 ◽  
Vol 101 (5) ◽  
pp. e246-e256 ◽  
Author(s):  
J. L. De Boever ◽  
K. Goossens ◽  
N. Peiren ◽  
J. Swanckaert ◽  
B. Ampe ◽  
...  

2001 ◽  
Vol 84 ◽  
pp. E31-E38 ◽  
Author(s):  
M.M. Schutz ◽  
E.A. Pajor
Keyword(s):  

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