Genetic correlations between mature cow weight and productive and reproductive traits in Nellore cattle

Context The selection of animals for sexual precocity and reproductive efficiency is a trend to reduce the production cycle, promote higher economic viability to the system, increase selection intensity and higher genetic gain, as well to promote the profitability of production systems. To include these traits as selection criterion in cattle breeding programs, estimating genetic parameters and studying the possibility of obtaining genetic gains is required. The hypothesis tested was that the indicators of sexual precocity traits present genetic variance and moderate heritability that allows these to be used as a criterion of selection to obtain improvement for sexual precocity, without negative implications for the reproductive efficiency in Nellore cattle. Aims This study was carried out to estimate the genetic parameters for reproductive traits (scrotal circumference at 365 and 450 days of age, gestation length, days open, calving interval, real fertility, cumulative productivity, calf weight:cow weight ratio) and age at first conception and first calving in a Nellore cattle herd under selection for sexual precocity. Methods Data of reproductive traits and indicators of sexual precocity traits from 4081 Nellore cattle born between 2009 and 2015 were used. The covariance components, heritabilities and correlations were estimated using the restricted maximum likelihood method, available in the BLUPF90 package, in single- and multiple-trait animal mixed models. Key results Estimates of heritability and standard errors for scrotal circumference at 365 and 450 days of age, gestation length, days open, calving interval, real fertility, cumulative productivity, calf weight:cow weight ratio, age at first conception (AFCo) and age at first calving (AFCa) were 0.33 ± 0.03, 0.33 ± 0.01, 0.23 ± 0.03, 0.34 ± 0.11, 0.23 ± 0.12, 0.21 ± 0.16, 0.23 ± 0.08, 0.25 ± 0.10, 0.21 ± 0.08 and 0.24 ± 0.08 respectively. The genetic correlations estimated between AFCo and the other reproductive traits ranged from –0.61 to 0.14 (standard error 0.1–0.21), and between AFCa and the other reproductive traits ranged from –0.60 to 0.16 (standard error 0.1–0.19), all of them in a favourable direction. Conclusions Selection for sexual precocity based on AFCo and AFCa may promote improvement in reproductive efficiency and fertility, except for the calf weight:cow weight ratio, whose correlation was close to zero. Implications The estimates of heritabilities and genetic correlations suggest that selection programs for reproductive traits and indicators of sexual precocity traits for the Nellore breed may provide genetic gain. In addition, considering the genetic correlation obtained between AFCo and AFCa (0.96), when the selection objective is to increase the sexual precocity of heifers, we could use the age of the first conception as criterion, as the measurement of this trait occurs at a lower age at first calving, which implies reducing the time required for animal evaluation and decision-making.

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Genetic analysis of visual assessment and body weight traits and their relationships with reproductive traits in Nellore cattle

The Journal of Agricultural Science ◽

10.1017/s0021859617000028 ◽

2017 ◽

Vol 155 (4) ◽

pp. 679-687 ◽

Cited By ~ 3

Author(s):

F. M. PATERNO ◽

M. E. BUZANSKAS ◽

W. KOURY FILHO ◽

R. B. LÔBO ◽

S. A. QUEIROZ

Keyword(s):

Body Weight ◽

Selection Criteria ◽

Genetic Correlations ◽

Heritability Estimate ◽

Reproductive Traits ◽

Visual Assessment ◽

Bayesian Analyses ◽

Age At First Calving ◽

Nellore Cattle ◽

Selection Of

SUMMARYGenetic parameters for visual assessment traits measured at 487 days of age (body structure (BS), finishing precocity (FP) and muscling (MS)), body weight at 450 days of age (W450), age at first calving (AFC), heifer pregnancy (HP) and stayability (STAY, i.e. the probability of a cow to produce at least three calves before reaching 76 months of age) were estimated in Nellore cattle, seeking to include these traits in the selection criteria for dams. The statistical models included additive genetic and residual random effects using single- and two-trait Bayesian analyses. The average heritability estimates were equal to 0·37 for BS, 0·42 for FP, 0·37 for MS and 0·48 for W450. Age at first calving had a low average heritability estimate (0·13), while HP and STAY estimates were higher (0·36 and 0·24, respectively). The genetic correlations between AFC, HP and STAY with visual assessment traits and body weight were favourable, indicating that selecting animals with higher BS, FP, MS and W450 values will result in the indirect selection of animals with lower AFC and successful scores for HP and STAY. The selection of heifers that present an early pregnancy should anticipate AFC and improve HP in the current herd. Except for AFC, the heritability and genetic correlation estimates between the studied traits justify their inclusion in the selection criteria of the Nellore breeding programme.

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PSVII-29 Genetic analysis of frame score and performance traits in Nellore cattle – reproduction and productivity traits

Journal of Animal Science ◽

10.1093/jas/skab235.433 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 238-238

Author(s):

Fernando S Baldi ◽

Maria Paula Negreiros ◽

Elisa Peripolli ◽

Claudio U Magnabosco ◽

Nayanny Guimarães ◽

...

Keyword(s):

Animal Model ◽

Bos Taurus ◽

Bos Indicus ◽

Genetic Correlations ◽

Genetic Selection ◽

Heritability Estimate ◽

Reproductive Traits ◽

Scrotal Circumference ◽

Nellore Cattle ◽

Cattle Reproduction

Abstract Frame score systems developed for Bos taurus breeds do not translate well for Bos indicus breeds, as these tend to be taller. We evaluated a novel frame score system for Nellore cattle raised on pasture [Guimaraes et al., 2020 J, Anim. Sci. 98 (Suppl. 4)]. Traits included adjusted scrotal circumference (cm) at 365 (SC365) and 450 (SC450) days of age, age at first calving (AFC, d), early heifer pregnancy (EHP, % calving as two-year-olds), stayability (STAY, % of cows remaining in the herd over 76 months of age, calving at least three times), and accumulated productivity (AP, kg of calf weaned per cow per year). In this study, we applied the previously developed equations (that also include hip height (HH, cm) and age to 12,049 records from the National Association of Breeders and Researchers (ANCP) database:FSmales= -20.35 + 0.1305*REA + 0.2633*BF - 0.5901*RF + 0.1139*HH + 0.0056*AGEFSfemales = -11.87 + 0.1316*REA - 0.2457*BF - 0.6218*RF + 0.1139*HH + 0.0009507*AGEThe (co)variance components and genetic parameters were estimated using a linear animal model or a threshold animal model depending on the trait. The heritability estimate for frame score was moderate (0.30). Estimated genetic correlations for reproductive traits were low to moderate (SC365, 0.06; SC450, 0.04; AFC, 0.18; EHP, -0.24; STAY, 0.06; AP, 0.25). The estimates support the notion that larger frame animals are later maturing but have greater lifetime productivity. The new frame score may be a useful tool for genetic selection of animals that are best suited to their environment.

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Multiple biological mechanisms result in correlations between pre- and post-mating traits that differ among versus within individuals and genotypes

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2018.0951 ◽

2018 ◽

Vol 285 (1885) ◽

pp. 20180951 ◽

Cited By ~ 4

Author(s):

Cristina Tuni ◽

Chang S. Han ◽

Niels J. Dingemanse

Keyword(s):

Empirical Studies ◽

Genetic Correlations ◽

Reproductive Traits ◽

Fertilization Success ◽

Male Quality ◽

Biological Mechanisms ◽

Environmental Correlations ◽

Ejaculate Size ◽

Trade Offs ◽

The Hierarchical Structure

Reproductive traits involved in mate acquisition (pre-mating traits) are predicted to covary with those involved in fertilization success (post-mating traits). Variation in male quality may give rise to positive, and resource allocation trade-offs to negative, covariances between pre- and post-mating traits. Empirical studies have yielded mixed results. Progress is hampered as researchers often fail to appreciate that mentioned biological mechanisms can act simultaneously but at different hierarchical levels of biological variation: genetic correlations may, for example, be negative due to genetic trade-offs but environmental correlations may instead be positive due to individual variation in resource acquisition. We measured pre-mating (aggression, body weight) and post-mating (ejaculate size) reproductive traits in a pedigreed population of southern field crickets ( Gryllus bimaculatus ). To create environmental variation, crickets were raised on either a low or a high nymphal density treatment. We estimated genetic and environmental sources of correlations between pre- and post-mating traits. We found positive genetic correlations between pre- and post-mating traits, implying the existence of genetic variation in male quality. Over repeated trials of the same individual (testing order), positive changes in one trait were matched with negative changes in other traits, suggesting energy allocating trade-offs within individuals among days. These findings demonstrate the need for research on pre- and post-mating traits to consider the hierarchical structure of trait correlations. Only by doing so was our study able to conclude that multiple mechanisms jointly shape phenotypic associations between pre- and post-mating traits in crickets.

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PSVII-28 Genetic analysis of frame score and performance traits in Nellore cattle–growth, carcass and efficiency traits

Journal of Animal Science ◽

10.1093/jas/skab235.434 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 238-239

Author(s):

Maria Paula Negreiros ◽

Elisa Peripolli ◽

Claudio U Magnabosco ◽

Nayanny Guimarães ◽

Raysildo Lôbo ◽

...

Keyword(s):

Animal Model ◽

Growth Traits ◽

Genetic Correlations ◽

Genetic Selection ◽

Heritability Estimate ◽

Score System ◽

Adult Weight ◽

Nellore Cattle ◽

And Performance ◽

Selection Of

Abstract We evaluated a novel frame score system for Nellore cattle raised on pasture (Guimarães et al., 2020 J, Anim. Sci. 98 (Suppl. 4)). Growth traits included age-adjusted weights (kg) at birth (W0), 120 (W120), 210 (W210) and 450 (W450) days of age, and adult weight (AW). Carcass traits (by ultrasound) included ribeye area (REA, cm2), 12th-13th rib backfat (BF, mm), rump fat (RF, mm), and intramuscular fat (IMF, %). Feed efficiency traits included residual feed intake (RFI, kg of DM/d) and DM intake (DMI, kg/d). We applied the previously developed equations (that also include hip height (HH, cm) and age to 12,049 records from the National Association of Breeders and Researchers (ANCP) database:FSmales= -20.35 + 0.1305*REA + 0.2633*BF - 0.5901*RF+ 0.1139*HH + 0.0056*AGEFSfemales = -11.87 + 0.1316*REA - 0.2457*BF - 0.6218*RF + 0.1139*HH + 0.0009507*AGEThe (co)variance components and genetic parameters were estimated using a linear animal model or a threshold animal model depending on the trait. The heritability estimate for frame score was moderate (0.30). Estimated genetic correlations were moderate for growth traits (W0, 0.51; W120, 0.41; W210, 0.35; W450, 0.29; AW, 0.39). Estimated genetic correlations for carcass and efficiency traits ranged from low to high (REA, 0.50; BF, -0.25; RF, -0.84; IMF, -0.15; DMI, 0.29; RFI, 0.10). The estimates support the notion that larger frame animals are heavier, leaner and later maturing, and less feed efficient. The new frame score may be a useful tool for genetic selection of animals that are best suited to their environment.

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Genetic parameter estimates (full sib and half sib analysis) of fertility and hatchability in two strains of Rhode Island chickens

Nigerian Journal of Animal Production ◽

10.51791/njap.v38i1.706 ◽

2021 ◽

Vol 38 (1) ◽

pp. 14-22

Author(s):

M. Orunmuyi ◽

I. A. Adeyinka ◽

O.O Oni

Keyword(s):

Rhode Island ◽

Additive Genetic Variance ◽

Genetic Parameter ◽

Genetic Correlations ◽

Reproductive Traits ◽

Parameter Estimates ◽

Phenotypic Correlations ◽

Poultry Breeding ◽

Genetic And Phenotypic Correlations ◽

Heritability Estimates

A study was conducted to estimate the genetic parameters of fertility and hatchability in two strains of Rhode Island Red (RIR) Chickens denoted as Strain A and Strain B respectively using the full-sib (sire +dam variance) and maternal half-sib (dam variance) components. The birds were obtained from the selected populations of RIR Chickens kept at the poultry breeding programme of National Animal Production Research Institute, Shika, Zaria, Nigeria. Settable eggs were collected from mating 28 cocks to 252 hens in a ratio of 1cock:9 hens from each strain. Eggs were pedigreed according to sire and dam. Results showed that values obtained for number of egg set (EGGSET), number of fertile eggs (NFERT), number of hatched chicks (NHATCH), percentage of chicks hatched from total eggs set (PHATCH) and percentage of chicks hatched from fertile eggs (PHATCHBL) were all higher in strain A than strain B. Heritability estimates obtained from the full-sib and maternal half-sib analysis ranged from medium to high for the two strains (0.24-0.96). The maternal half sib estimates were higher (0.40-0.96) than the estimates obtained from full sibs (0.24- 0.48). Genetic and phenotypic correlations obtained for both strains were positive and similar regardless of method of estimation. Genetic correlations between EGGSET and PFERT were low in strain A using both full-sib and maternal half-sib analyses (0.09-0.14). Phenotypic correlations between EGGSET and PFERT, PHATCH and PHATCHBL were also low in both strains and regardless of method of analyses. Moderate to high heritability estimates suggest that genetic improvement can be obtained by selection of these reproductive traits. The full-sib analysis for estimating heritability will be preferred since it is assumed that only additive genetic variance contributes to the covariance between family members.

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Phenotypic and genetic parameters for reproductive performance in a synthetic line of sheep

The Journal of Agricultural Science ◽

10.1017/s0021859600031920 ◽

1981 ◽

Vol 96 (1) ◽

pp. 107-113 ◽

Cited By ~ 11

Author(s):

T. G. Martin ◽

D. Nicholson ◽

C. Smith ◽

D. I. Sales

Keyword(s):

Reproductive Performance ◽

Genetic Parameters ◽

Genetic Correlations ◽

Reproductive Traits ◽

Direct Selection ◽

Sex Distribution ◽

Regression Methods ◽

Litter Weight ◽

Heritability Estimates ◽

Synthetic Line

SUMMARYData on 902 ewes (1755 records) bom over 7 years in the synthetic ABRO Dam Line were analysed by least squares. Reproductive traits of the ewe were not affected by whether she was a single or a twin or by the age of her dam. Ewe age had major effects on all reproductive traits. Litter weight traits were affected by the sex distribution and the age of the litter when weighed.Heritability estimates, both by half sib and regression methods, were low for litter size, low to moderate for litter weights, and higher for ewe and fleece weights. Genetic correlations among the litter-weight traits were high. Together with the heritability estimates, they indicated that selection on litter weight at birth (and perhaps other traits) might give a greater change in total litter weight at weaning, the main measure of ewe productivity and the objective in improvement, than would direct selection.

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Genetic correlations for reproductive and growth traits in rabbits

Canadian Journal of Animal Science ◽

10.1139/cjas-2019-0049 ◽

2020 ◽

Vol 100 (2) ◽

pp. 317-322 ◽

Cited By ~ 1

Author(s):

Rym Ezzeroug ◽

Rafik Belabbas ◽

Maria José Argente ◽

Ali Berbar ◽

Samir Diss ◽

...

Keyword(s):

Litter Size ◽

Coefficient Of Variation ◽

Growth Traits ◽

Genetic Correlations ◽

Reproductive Traits ◽

High Coefficient ◽

Genetic And Phenotypic Correlations ◽

The Common ◽

Large Coefficient ◽

Size At Birth

The objective of this study was to obtain heritability estimates for reproductive (litter size at birth, number born alive, litter size at weaning) and growth traits (individual weaning weight, individual weight at the end of the fattening period), then determine the genetic correlation between them in a synthetic rabbit line. A total of 805 females, 3242 parities, and 18 472 growth records were measured from 2006 to 2017. A pentavariate animal model was used with reproductive and growth traits. Heritability ranged from 0.025 to 0.126 for reproductive traits and from 0.033 to 0.059 for growth traits. These traits showed a large coefficient of variation (from 32% to 56% for reproductive traits and from 21% to 28% for growth traits). The repeatability of reproductive traits was low and the common litter effect for growth traits was the most important component of total variance. The genetic and phenotypic correlations between reproductive and growth traits were high and negative, especially with weight at weaning (−0.848, −0.922, and −0.854 for litter size at birth, number born alive, and litter size at weaning, respectively). In conclusion, because of the high negative correlation between reproductive and growth traits, both reproductive and growth traits should be selected in independent lines and the response to selection should be due mainly to the high coefficient of variation of the traits.

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Genetic correlations and trends for traits of economic importance in dairy buffalo

Animal Production Science ◽

10.1071/an19051 ◽

2020 ◽

Vol 60 (4) ◽

pp. 492 ◽

Cited By ~ 1

Author(s):

Ranielle Nogueira da Silva Vilela ◽

Thomaz Marques Sena ◽

Rusbel Raul Aspilcueta-Borquis ◽

Leonardo de Oliveira Seno ◽

Francisco Ribeiro de Araujo Neto ◽

...

Keyword(s):

Milk Fat ◽

Genetic Correlations ◽

Reproductive Traits ◽

Milk Quality ◽

Calving Interval ◽

Age At First Calving ◽

Productive Traits ◽

Dairy Buffalo ◽

Genetic Trends ◽

Low Magnitude

Context The planning and execution of selection programs requires estimates of the genetic correlations between traits. As genetic change is achieved for a given trait, it is important to consider possible genetic changes for other traits. Understanding the magnitude and direction of genetic correlations can assist in selection decisions. Aims The aim of the present study was to estimate the genetic correlations of reproductive traits with productive traits and with percentages of fat and protein in the milk of dairy buffalo. Additionally, genetic trends were estimated for the traits under study over the years. Methods Data from 11530 complete lactations of 3431 female buffalo were used. The following traits were analysed: milk, fat and protein yields; percentages of fat and protein; age at first calving; and calving interval. The (co)variance components were estimated by Bayesian inference in multi-trait analyses, considering a linear animal model. To calculate the genetic trends, the average annual genetic values were regressed on the year of birth. Key results The means of genetic correlations estimated between reproductive (age at first calving and calving interval) and productive (milk, fat and protein yields) traits were positive, but of moderate to low magnitude. The association between the reproductive and milk quality (fat and protein percentages) traits were negative and of low magnitude. Genetic trends for the productive traits were positive (5.25 ± 0.63, 0.15 ± 0.034 and 0.09 ± 0.038 kg/year for milk, fat and protein yields respectively). Genetic trends for the reproductive traits of age at first calving and calving interval increased by 0.47 ± 0.09 and 0.48 ± 0.10 days/year respectively. In terms of milk quality, however, the percentages of fat and protein decreased by 0.016 ± 0.003 and 0.011 ± 0.001%/year respectively. Conclusions Genetic gains in productive traits may elevate the number of days at first calving and extend the calving interval, in addition to leading to the production of milk of lower quality. Implications The use of a multi-trait selection index is an alternative, as it combines information from different sources, such that an optimal selection criterion can be achieved over time by virtue of its emphasis on appropriate weighting for all traits.

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