Assessment of methane emission traits in ewes using a laser methane detector: genetic parameters and impact on lamb weaning performance

Abstract. The aim of the present study was to derive individual methane (CH4) emissions in ewes separated in CH4 respiration and eructation traits. The generated longitudinal CH4 data structure was used to estimate phenotypic and genetic relationships between ewe CH4 records and energy efficiency indicator traits from same ewes as well as from their lambs (intergenerational perspective). In this regard, we recorded CH4 emissions via mobile laser methane detector (LMD) technique, body weight (EBW), backfat thickness (BFT) and body condition score (BCS) from 330 ewes (253 Merinoland (ML), 77 Rhön sheep (RH)) and their 629 lambs (478 ML, 151 RH). The interval between repeated measurements (for ewe traits and lamb body weight (LBW)) was 3 weeks during lactation. For methane concentration (µL L−1) determinations in the exhaled air, we considered short time measurements (3 min). Afterwards, CH4 emissions were portioned into a respiration and eructation fraction, based on a double normal distribution. Data preparation enabled the following CH4 trait definitions: mean CH4 concentration during respiration and eructation (CH4r+e), mean CH4 concentration during respiration (CH4r), mean CH4 concentration during eructation (CH4e), sum of CH4 concentrations per minute during respiration (CH4rsum), sum of CH4 concentrations per minute during eructation (CH4esum), maximal CH4 concentration during respiration (CH4rmax), maximal CH4 concentration during eructation (CH4emax), and eructation events per minute (CH4event). Large levels of ewe CH4 emissions representing energy losses were significantly associated with lower LBW (P<0.05), lower EBW (P<0.01) and lower BFT (P<0.05). For genetic parameter estimations, we applied single- and multiple-trait animal models. Heritabilities and additive genetic variances for CH4 traits were small, i.e., heritabilities in the range from <0.01 (CH4r+e, CH4r, CH4rmax, CH4esum) to 0.03 (CH4rsum). We estimated negative genetic correlations between CH4 traits and EBW in the range from −0.44 (CH4r+e) to −0.05 (CH4rsum). Most of the CH4 traits were genetically negatively correlated with BCS (−0.81 for CH4esum) and with BFT (−0.72 for CH4emax), indicating same genetic mechanisms for CH4 output and energy efficiency indicators. Addressing the intergenerational aspect, genetic correlations between CH4 emissions from ewes and LBW ranged between −0.35 (CH4r+e) and 0.01 (CH4rsum, CH4rmax), indicating that breeding on reduced CH4 emissions (especially eructation traits) contribute to genetic improvements in lamb weaning performance.

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Relationships between body reserve dynamics and rearing performances in meat ewes1

Journal of Animal Science ◽

10.1093/jas/skz273 ◽

2019 ◽

Vol 97 (10) ◽

pp. 4076-4084

Author(s):

Tiphaine Macé ◽

Dominique Hazard ◽

Fabien Carrière ◽

Sebastien Douls ◽

Didier Foulquié ◽

...

Keyword(s):

Genetic Relationships ◽

Genetic Correlations ◽

Repeated Measurements ◽

Production Cycle ◽

Data Sets ◽

Data Set ◽

Litter Weight ◽

Significant Relationships ◽

Physiological Stage ◽

Changes Over Time

Abstract The main objective of this work was to study the relationships between body reserve (BR) dynamics and rearing performance (PERF) traits in ewes from a Romane meat sheep flock managed extensively on “Causse” rangelands in the south of France. Flock records were used to generate data sets covering 14 lambing years (YR). The data set included 1,146 ewes with 2 ages of first lambing (AGE), 3 parities (PAR), and 4 litter sizes (LS). Repeated measurements of the BW and BCS were used as indicators of BR. The ewe PERF traits recorded were indirect measurements for maternal abilities and included prolificacy, litter weight and lamb BW at lambing and weaning, ADG at 1, 2, and 3 mo after lambing, and litter survival from lambing to weaning. The effects of different BW and BCS trajectories (e.g., changes in BW and BCS across the production cycle), previously been characterized in the same animals, on PERF traits were investigated. Such trajectories reflected different profiles at the intraflock level in the dynamics of BR mobilization–accretion cycles. Genetic relationships between BR and PERF traits were assessed. All the fixed variables considered (i.e., YR, AGE, PAR, LS, and SEX ratio of the litter) have significant effects on the PERF traits. Similarly, BW trajectories had an effect on the PERF traits across the 3 PARs studied, particularly during the first cycle (PAR 1). The BCS trajectories only affected prolificacy, lamb BW at birth, and litter survival. Most of the PERF traits considered here showed moderate heritabilities (0.17–0.23) except for prolificacy, the lamb growth rate during the third month and litter survival which showed very low heritabilities. With exception of litter survival and prolificacy, ewe PERF traits were genetically, strongly, and positively correlated with BW whatever the physiological stage. A few weak genetic correlations were found between BCS and PERF traits. As illustrated by BW and BCS changes over time, favorable genetic correlations were found, even if few and moderate, between BR accretion or mobilization and PERF traits, particularly for prolificacy and litter weight at birth. In conclusion, our results show significant relationships between BR dynamics and PERF traits in ewes, which could be considered in future sheep selection programs aiming to improve robustness.

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Genetic parameter estimates for important traits on the fifth generation in red tilapia in Vietnam

The Journal of Agriculture and Development ◽

10.52997/jad.7.01.2021 ◽

2021 ◽

Vol 20 (1) ◽

pp. 49-57

Author(s):

Sang V. Nguyen

Keyword(s):

Body Weight ◽

Survival Rate ◽

Genetic Parameters ◽

Genetic Parameter ◽

Genetic Correlations ◽

Parameter Estimates ◽

Environment Interaction ◽

Body Colour ◽

Red Tilapia ◽

Gxe Interaction

Genetic parameters comprising heritability, genetic correlation and genotype by environment interaction (GxE) for growth survival rate and body colour at harvest were estimated on the 5th selective generation of red tilapia grown in two environments, freshwater and brackishwater ponds. A total of 116 full-half-sib families was produced as well as 4,432 and 3,811 tagged individuals were tested in freshwater and brackishwater ponds, respectively. Genetic parameters were estimated by ASReml 4.1 software. The heritability for body weight and survival rate was high while medium heritability for body colour in freshwater was observed. The heritability for those traits of red tilapia in brackishwater. Together with the figures in earlier publication on previous generations (G1 to G4) in the same selective population, the expected medium to high response acquires if selection is done for each trait. Genetic correlations among harvest body weight, survival rate and body colour are insignificantly different and ranging from -0.25 to 0.37 (P > 0.05). These results implied that selection on one trait do not influence on responses of the other traits. GxE interaction for body weight and body colour between two tested environments is mostly negligible with genetic correlations ranging from 0.63 - 0.80 while it is important for survival trait (rg = -0.17 ± 0.40).

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Heritability of chronic interstitial nephropathy and its genetic relationships with laying intensity and body weight in Muscovy ducks

Canadian Journal of Animal Science ◽

10.4141/cjas93-084 ◽

1993 ◽

Vol 73 (4) ◽

pp. 823-827

Author(s):

C. Beaumont ◽

E. Le Bihan ◽

Y. Cherel ◽

M. Wyers ◽

B. Retailleau

Keyword(s):

Body Weight ◽

Genetic Parameters ◽

Genetic Relationships ◽

Major Gene ◽

Genetic Correlations ◽

Genetic Resistance ◽

Components Of Variance ◽

Interstitial Nephropathy ◽

Muscovy Ducks ◽

Selection For

Heritability of chronic interstitial nephropathy was estimated from analysis of all-or-none traits for 1969 female Muscovy ducks, which were the progeny of 47 sires and 263 dams. Heritability estimates for the sire and dam components were 0.57 and 0.32, respectively. From sire or dam components of variance, genetic correlations with total number of eggs laid were 0.29 and 0.44 and with body weight at 10 wk were 0.18 and 0.08. Existence of a major gene affecting resistance to the disease was suspected. These results suggest that selection for resistance against this disease could be effective without excessive losses in laying intensity or body weight. Key words: Genetic resistance, nephropathy, Muscovy ducks, genetic parameters, laying intensity

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Genetic aspects of condition score, heart girth and milk-yield traits in Italian Friesian cows

BSAP Occasional Publication ◽

10.1017/s1463981500043181 ◽

1999 ◽

Vol 24 ◽

pp. 159-164

Author(s):

L. Gallo ◽

P. Carnier ◽

M. Cassandro ◽

R. Dal Zotto ◽

G. Bittante

Keyword(s):

Milk Yield ◽

Genetic Relationships ◽

Genetic Correlations ◽

Repeated Measurements ◽

Protein Yield ◽

Yield Traits ◽

Dry Period ◽

Condition Score ◽

Heritability Estimates ◽

Friesian Cows

AbstractFunctional traits related to costs are currently of interest for selection and management of dairy cattle. The present study was aimed to estimate heritability for body condition score (BCS) and heart girth (HG), to investigate the genetic relationships between BCS, HG and milk-yield traits using a test-day model and to analyse the consistency of the estimates in different lactation stages. Cows from 25 dairy herds were scored for BCS and measured for HG at 3-month intervals for 2 years. Approximately 5000 test-day observations on BCS, HG and milk fat and protein yield from 1429 Italian Friesian cows were analysed using two approaches: (1) repeated observations were treated as repeated measurements of the same trait, both within and across lactations; (2) observations collected in different stages of lactation (dry period, 1 to 75 days in milk (DIM), 76 to 130 DIM, 131 to 210 DIM, 211 to 300 DIM) were treated as different traits. (Co)variance components and related parameters were estimated using REML multiple-trait procedures and unequal design animal models.Heritability estimates (approach 1) for fat and protein test-day yield, BCS and HG were 0.22, 0.18, 0.29 and 0.33, respectively. BCS was negatively correlated with yield traits (-0.43 and -0.48 for fat and protein yield, respectively) but positively correlated (0.33) with HG. Genetic relationships between HG and milk-yield traits were negligible. Heritability estimates (approach 2) were 0.28 and 0.27 for BCS recorded in the first half of lactation (1 to 75 and 76 to 130 DIM, respectively), 0.36 for BCS measured on cows in the second half of lactation and 0.32 for BCS recorded on dry cows. Heritability estimates for HG in different lactation stages ranged from 0.31 to 0.40. Genetic correlations between BCS measured in different lactation stages were generally high (0.85 or more), with the exception of the correlation between the first and the last stage of lactation (0.74) and of the relationships between the beginning of lactation and the dry period (0.7). Genetic correlations between HG measured in different lactation stages were mostly higher than 0.80.

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Evaluation of Bonsmara and Belmont Red cattle breeds in South Africa. 2. Genetic parameters for growth and fertility

Australian Journal of Experimental Agriculture ◽

10.1071/ea05224 ◽

2006 ◽

Vol 46 (2) ◽

pp. 213 ◽

Cited By ~ 4

Author(s):

N. J. Corbet ◽

R. K. Shepherd ◽

H. M. Burrow ◽

K. C. Prayaga ◽

J. van der Westhuizen ◽

...

Keyword(s):

South Africa ◽

Maternal Effects ◽

Genetic Parameters ◽

Growth Traits ◽

Genetic Parameter ◽

Genetic Correlations ◽

Repeated Measurements ◽

Maternal Influence ◽

Parameter Estimates ◽

Fertility Traits

Genetic parameters were estimated for growth and fertility indicator traits in a South African beef cattle population. Measurements on 5601 pedigreed progeny of 96 Bonsmara sires, 18 Belmont Red sires and 20 Bonsmara × Belmont Red cross sires were recorded over 19 years in 4 diverse climatic regions of South Africa. Growth traits were measured on growing stock from birth to 18 months at pasture. Cow weights were measured at calving and weaning. Age at first calving, and repeated measurements of calving day and calving interval were recorded on 1993 breeding females as indicators of reproductive performance. The traits were analysed using univariate and bivariate animal models with maternal effects fitted. Direct heritability of growth traits (0.11–0.42) and female fertility traits (0.02–0.13) suggested that genetic progress could be made by selection for some traits. Genetic correlations between growth and fertility traits were variable (–0.47–0.85) and indicated that multi-trait selection would be the best method of dealing with multidirectional forces on productivity traits. Genetic correlations between direct and maternal effects on liveweight traits were mostly negative indicating that genetic improvement of traits with strong maternal influence, such as weaning weight, would be complicated and supported the use of post-weaning weights with less maternal influence as selection criteria to improve the direct additive component of growth. The genetic parameter estimates provide useful reference values for estimation of breeding values in a proposed combined-breed genetic evaluation program.

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Genetic variation in litter size and 12-day weight in mice and their relationships with post-weaning growth

Animal Science ◽

10.1017/s0003356100022546 ◽

1974 ◽

Vol 19 (1) ◽

pp. 13-23 ◽

Cited By ~ 14

Author(s):

J. P. Hanrahan ◽

E. J. Eisen

Keyword(s):

Body Weight ◽

Litter Size ◽

Maternal Effects ◽

Negative Correlation ◽

Genetic Relationships ◽

Genetic Correlations ◽

Genetic Effects ◽

Direct Effects ◽

Body Weights ◽

Sources Of Variation

SUMMARYData from a random-bred population of mice were used to examine the sources of variation in litter size and 12-day body weight, and, the genetic relationships between these traits and post-weaning body weights and body-weight gain from 3 to 6 weeks of age (post-weaning gain). The genetic model included maternal genetic effects in addition to the usual direct (individual) genetic effects. Such maternal genetic effects may be important to an understanding of traits like 12-day body weight of mice, where the young depend to a large extent on the mother for early postnatal nutrition.Analysis of litter size yielded a paternal half-sib heritability estimate of 0·34±0·19, while twice the daughter-dam regression was 0·23 ± 0·08. The repeatability of litter size was 0·51±0·07. The correlation between direct genetic effects on litter size and those on 3-, 6-, and 8- week body weights and post-weaning gain were –0·18,0·36,0-34 and 0·58 respectively. The correlation between direct genetic effects on litter size and 12-day weight was positive (0·41), while the genetic correlation between maternal effects on 12-day weight and direct effects on litter size was negative (–0·37).Analysis of 12-day weight showed that direct and maternal genetic effects were important sources of variation, but there was a large negative correlation (-0·88) between these effects. The usual genetic correlations between 12-day weight and post-weaning body weights were positive while post-weaning gain yielded a negative estimate. However, there appears to be a general negative correlation between direct genetic and maternal genetic effects in this population, for all such correlations were negative except that between direct effects on 12-day weight and maternal effects on post-weaning gain.

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Assessment of Genetic Relationships between Growth Traits and Milk Yield in Egyptian Buffaloes

Jurnal Ilmu Ternak dan Veteriner ◽

10.14334/jitv.v24i4.2034 ◽

2019 ◽

Vol 24 (4) ◽

pp. 143

Author(s):

Ibrahim Abu El- Naser

Keyword(s):

Body Weight ◽

Milk Yield ◽

Genetic Parameters ◽

Growth Traits ◽

Genetic Relationships ◽

Genetic Correlations ◽

Live Body Weight ◽

Body Weights ◽

Production Research ◽

Maternal Heritability

Data in this study were collected from live body weight records and milk yield for the first three lactations of Egyptian buffaloes maintained at the Mahallet Mousa Experimental Station of Animal Production Research Institute, relying on 987 records of Egyptian buffaloes spread over 16 years. These data were analyzed to estimate genetic parameters using animal model. Overall means in kilograms of BW, WW, W18, WFC, 1stMY, 2ndMY and 3rdMY were 36.56, 96.95, 322.02, 462.09, 1561.53, 1755 and 1837.71, respectively. Direct additive heritability (h2a) for mentioned traits were 0.31, 0.22, 0.24, 0.27, 0.23, 0.23 and 0.17, respectively. Corresponding computation of maternal heritability (h2m) for same traits were 0.39, 0.34, 0.22, 0.40, 0.29, 0.31 and 0.21, respectively. Evaluation of genetic correlations among different all studied traits were positive and ranged from 0.07 to 0.83, while phenotypic correlations were positive and ranged from 0.02 to 0.55. Accuracy of (PBV's) varying from 62 to 76, 62 to 83 and 41 to 77% for sires, cows and dams, successively; pointing out the genetic improvement could be achieved through any pathway of them. Higher direct and maternal heritability for BW and WFC and genetic correlations between first three lactations milk yield and each of BW and WFC higher than genetic correlations between first three lactations milk yield and WW and W18. Therefore, it is appropriate to select buffalo female calves for live body weight at birth than for live body weights at other ages.

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Realized Sampling Variances of Estimates of Genetic Parameters and the Difference Between Genetic and Phenotypic Correlations

Genetics ◽

10.1093/genetics/143.3.1409 ◽

1996 ◽

Vol 143 (3) ◽

pp. 1409-1416 ◽

Cited By ~ 1

Author(s):

Kenneth R Koots ◽

John P Gibson

Keyword(s):

Genetic Correlation ◽

Genetic Parameters ◽

Genetic Parameter ◽

Genetic Correlations ◽

Phenotypic Correlation ◽

Parameter Estimates ◽

Sampling Variance ◽

Phenotypic Correlations ◽

Genetic And Phenotypic Correlations ◽

Heritability Estimates

Abstract A data set of 1572 heritability estimates and 1015 pairs of genetic and phenotypic correlation estimates, constructed from a survey of published beef cattle genetic parameter estimates, provided a rare opportunity to study realized sampling variances of genetic parameter estimates. The distribution of both heritability estimates and genetic correlation estimates, when plotted against estimated accuracy, was consistent with random error variance being some three times the sampling variance predicted from standard formulae. This result was consistent with the observation that the variance of estimates of heritabilities and genetic correlations between populations were about four times the predicted sampling variance, suggesting few real differences in genetic parameters between populations. Except where there was a strong biological or statistical expectation of a difference, there was little evidence for differences between genetic and phenotypic correlations for most trait combinations or for differences in genetic correlations between populations. These results suggest that, even for controlled populations, estimating genetic parameters specific to a given population is less useful than commonly believed. A serendipitous discovery was that, in the standard formula for theoretical standard error of a genetic correlation estimate, the heritabilities refer to the estimated values and not, as seems generally assumed, the true population values.

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Corrigendum to: Consequences of genetic selection for environmental impact traits on economically important traits in dairy cows

Animal Production Science ◽

10.1071/an16592_co ◽

2018 ◽

Vol 58 (10) ◽

pp. 1966

Author(s):

Purna Kandel ◽

Sylvie Vanderick ◽

Marie-Laure Vanrobays ◽

Hélène Soyeurt ◽

Nicolas Gengler

Keyword(s):

Dairy Cows ◽

Body Condition Score ◽

Genetic Correlations ◽

Genetic Selection ◽

Selection Response ◽

Direct Selection ◽

Correlated Response ◽

Production Traits ◽

Ch4 Emissions ◽

Natural Logarithm

Methane (CH4) emission is an important environmental trait in dairy cows. Breeding aiming to mitigate CH4 emissions require the estimation of genetic correlations with other economically important traits and the prediction of their selection response. In this study, test-day CH4 emissions were predicted from milk mid-infrared spectra of Holstein cows. Predicted CH4 emissions (PME) and log-transformed CH4 intensity (LMI) computed as the natural logarithm of PME divided by milk yield (MY). Genetic correlations of PME and LMI with traits used currently were approximated from correlations between estimated breeding values of sires. Values were for PME with MY 0.06, fat yield (FY) 0.09, protein yield (PY) 0.13, fertility 0.17; body condition score (BCS) –0.02; udder health (UDH) 0.22; and longevity 0.22. As expected by its definition, values were negative for LMI with production traits (MY –0.61; FY –0.15 and PY –0.40) and positive with fertility (0.36); BCS (0.20); UDH (0.08) and longevity (0.06). The genetic correlations of 33 type traits with PME ranged from –0.12 to 0.25 and for LMI ranged from –0.22 to 0.18. Without selecting PME and LMI (status quo) the relative genetic change through correlated responses of other traits were in PME by 2% and in LMI by –15%, but only due to the correlated response to MY. Results showed for PME that direct selection of this environmental trait would reduce milk carbon foot print but would also affect negatively fertility. Therefore, more profound changes in current indexes will be required than simply adding environmental traits as these traits also affect the expected progress of other traits.

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