scholarly journals Study of relations among age at first calving, average weight gains and weights from weaning to maturity in Nellore cattle

2010 ◽  
Vol 39 (4) ◽  
pp. 746-751 ◽  
Author(s):  
Arione Augusti Boligon ◽  
Lucia Galvão de Albuquerque ◽  
Maria Eugênia Zerlotti Mercadante ◽  
Raysildo Barbosa Lôbo
Keyword(s):  
Weight Gain ◽  
Genetic Correlation ◽  
Maximum Likelihood Method ◽  
Selection Index ◽  
Likelihood Method ◽  
Average Weight ◽  
Age At First Calving ◽  
Nellore Cattle ◽  
Estimate Heritability ◽  
Selection For

Data from 23,120 Nellore animals were used to estimate genetic parameters for age at first calving, average gains from weaning to yearling and from yearling to after yearling, weaning weight, yearling weight, after yearling weight and weight at 2 and 5 years of age. Animal models were fitted by Restricted Maximum likelihood Method. Estimate heritability for age at first calving, weaning to yearling weight gain, yearling to after yearling weight gain, weight at weaning, yearling weight, after yearling weight and weight from 2 to 5 years of age were 0.17 ± 0.01; 0.23 ± 0.03; 0.25 ± 0.03; 0.28 ± 0.02; 0.26 ± 0.03; 0.30 ± 0.03; 0.32 ± 0.02 and 0.36 ± 0.04, respectively. The genetic correlation estimates between age at first calving and weight traits ranged from -0.26 to -0.14. The genetic correlation estimates between age at first calving and average gains were also negative, but higher (-0.29 and -0.32). In general, these results indicate that selection for average gains will promote changes in age at first calving and female mature weight. Improvement in reproductive performance could be obtained with the inclusion of the age at first calving in the selection index.

Genetic relations and indirect response to selection based on indices for scrotal circumference, visual scores and weight gain in beef cattle

2018 ◽  
Vol 58 (7) ◽  
pp. 1210 ◽  
Author(s):  
A. A. Boligon ◽  
P. P. Farias ◽  
V. M. Roso ◽  
M. L. Santana ◽  
A. B. Bignardi ◽  
...  
Keyword(s):  
Weight Gain ◽  
Beef Cattle ◽  
Selection Process ◽  
Selection Index ◽  
Genetic Correlations ◽  
Correlated Response ◽  
Indirect Response ◽  
Genetic Gains ◽  
Scrotal Circumference ◽  
Selection For

Genetic improvement in beef cattle involves evaluation for fertility, growth, carcass and visual scores traits. In general, genetic and economic parameters of these traits are considered for selection index construction. The present study was conducted to establish the magnitude of genetic and phenotypic correlations between visual scores of conformation, precocity and muscling at weaning and at yearling, birth to weaning weight gain, weaning to yearling weight gain and yearling scrotal circumference, and between these traits with selection indices applied in this population. In addition, the expected gains were obtained in such traits by taking under consideration the adopted selection criteria based on indices. Positive and high genetic correlations were estimated between weaning traits (visual scores and weight gain), ranging from 0.70 ± 0.02 to 0.97 ± 0.01. In genetic terms, the same visual scores, but evaluated in two ages (weaning and yearling) showed positive and high associations, with values of 0.90 ± 0.01 (conformation), 0.88 ± 0.01 (precocity) and 0.84 ± 0.02 (muscling). Genetic associations between yearling visual scores with scrotal circumference and weaning to yearling weight gain ranging from 0.36 ± 0.02 to 0.53 ± 0.01. Using the weaning index, are expected genetic gains ranging from 0.26% to 0.70%/year of the phenotypic mean of each weaning trait. Using the yearling index, annual genetic gains estimated for weaning traits (ranging from 0.25% to 0.63% of the phenotypic mean of the trait) were lower than that obtained at yearling (ranging from 0.27% to 0.98% of the phenotypic mean of the trait). Selection for one of traits obtained at weaning should result, by correlated response, in gain for the others. Also, the choice of animals with higher breeding values for weaning visual scores, beyond anticipate the selection process, should lead to favourable changes in these traits at yearling. Selection for better body composition at yearling (higher scores) should provide increase in scrotal circumference and weight gain. The use of higher values of the indices should result in positively correlated response, but in different magnitudes for each trait used in these indices. However, in both weaning and yearling, higher genetic gains to visual scores are expected in the same period, when the selection is based on the values of these indices.

Meta-analysis of genetic-parameter estimates for reproduction, growth and carcass traits in Nellore cattle by using a random-effects model

2018 ◽  
Vol 58 (9) ◽  
pp. 1575 ◽  
Author(s):  
Hinayah Rojas de Oliveira ◽  
Henrique Torres Ventura ◽  
Edson Vinícius Costa ◽  
Mariana Alencar Pereira ◽  
Renata Veroneze ◽  
...  
Keyword(s):  
Genetic Correlation ◽  
Random Effects ◽  
Meta Analysis ◽  
Carcass Traits ◽  
Parameter Estimates ◽  
Random Effects Model ◽  
Age At First Calving ◽  
Different Ages ◽  
Nellore Cattle ◽  
Heritability Estimates

Meta-analysis based on a random-effects model is used to summarise and overcome the variability between divergent parameter estimates. We proposed a meta-analysis of published heritability and genetic-correlation estimates for reproduction, growth and carcass traits in purebred Nellore cattle. In total, 197 heritability and 107 genetic-correlation estimates from 62 scientific publications were used here. Most of traits (gestation length; weights at birth, 120, 210, 365 and 550 days of age; mature weight and all carcass traits) presented direct heritability estimates ranging from 0.20 to 0.40. Age at first calving presented the lowest value among direct heritabilities (0.1498); whereas the higher values (>0.40) were found for scrotal circumference at different ages and for weight at 450 days of age. Low maternal heritability estimates (ranging from 0.06 to 0.11) were observed for all growth traits. With the exception of correlation estimates involving the age at first calving, all other correlations were positive. High correlations (>0.85) were found mainly for the same trait at different ages. The results reported here will give support to genetic evaluations when reliable estimates for different traits in purebred Nellore cattle are not available.

scholarly journals Genetic improvement of feed conversion ratio via indirect selection against lipid deposition in farmed rainbow trout (Oncorhynchus mykiss Walbaum)

2016 ◽  
Vol 116 (9) ◽  
pp. 1656-1665 ◽  
Author(s):  
Antti Kause ◽  
Anders Kiessling ◽  
Samuel A. M. Martin ◽  
Dominic Houlihan ◽  
Kari Ruohonen
Keyword(s):  
Rainbow Trout ◽  
Weight Gain ◽  
Feed Intake ◽  
Selection Index ◽  
Direct Selection ◽  
Genetic Response ◽  
Feed Conversion ◽  
Retention Efficiency ◽  
Muscle Lipid ◽  
Selection For

AbstractIn farmed fish, selective breeding for feed conversion ratio (FCR) may be possible via indirectly selecting for easily-measured indicator traits correlated with FCR. We tested the hypothesis that rainbow trout with low lipid% have genetically better FCR, and that lipid% may be genetically related to retention efficiency of macronutrients, making lipid% a useful indicator trait. A quantitative genetic analysis was used to quantify the benefit of replacing feed intake in a selection index with one of three lipid traits: body lipid%, muscle lipid% or viscera% weight of total body weight (reflecting visceral lipid). The index theory calculations showed that simultaneous selection for weight gain and against feed intake (direct selection to improve FCR) increased the expected genetic response in FCR by 1·50-fold compared with the sole selection for growth. Replacing feed intake in the selection index with body lipid%, muscle lipid% or viscera% increased genetic response in FCR by 1·29-, 1·49- and 1·02-fold, respectively, compared with the sole selection for growth. Consequently, indirect selection for weight gain and against muscle lipid% was almost as effective as direct selection for FCR. Fish with genetically low body and muscle lipid% were more efficient in turning ingested protein into protein weight gain. Both physiological and genetic mechanisms promote the hypothesis that low-lipid% fish are more efficient. These results highlight that in breeding programmes of rainbow trout, control of lipid deposition improves not only FCR but also protein-retention efficiency. This improves resource efficiency of aquaculture and reduces nutrient load to the environment.

scholarly journals Genetic parameters and response to selection for post-weaning weight gain, visual scores and carcass traits in Hereford and Hereford×Nellore cattle

2011 ◽  
Vol 137 (1-3) ◽  
pp. 231-237 ◽  
Author(s):  
Fábio Luiz Buranelo Toral ◽  
Vanerlei Mozaquatro Roso ◽  
Cláudio Vieira de Araújo ◽  
João Cruz Reis Filho
Keyword(s):  
Weight Gain ◽  
Genetic Parameters ◽  
Carcass Traits ◽  
Response To Selection ◽  
Weaning Weight ◽  
Nellore Cattle ◽  
Selection For

scholarly journals Estimates of correction factors for lactation length and genetic parameters for milk yield in buffaloes

2004 ◽  
Vol 56 (2) ◽  
pp. 251-257 ◽  
Author(s):  
H. Tonhati ◽  
M.F.C. Muñoz ◽  
J.M.C. Duarte ◽  
R.H. Reichert ◽  
J.A. Oliveira ◽  
...  
Keyword(s):  
Maximum Likelihood ◽  
Genetic Correlation ◽  
Milk Yield ◽  
Genetic Parameters ◽  
Maximum Likelihood Method ◽  
Environmental Parameters ◽  
Likelihood Method ◽  
Correction Factors ◽  
Lactation Length ◽  
Derivative Free

Correction factors for milk yield at 90, 240, 270 and 305 days of lactation of buffaloes and genetic and environmental parameters for milk yield of these lactation periods were estimated. The data used consisted of 3888 lactation records of 1630 buffaloes from 10 herds reared in the State of São Paulo. Genetic parameters were estimated by the derivative free restricted maximum likelihood method, fitting an animal repeatability model. Heritability estimates for milk yield corrected for 90, 240, 270 and 305 days of lactation were 0.17, 0.15, 0.14 and 0.14, respectively. In this same order, repeatability estimates were 0.40, 0.44, 0.41 and 0.41. The genetic correlation estimates between these corrected milk yields ranged from 0.96 to 1.00. The multiplicative correction factors for the different classes of lactation lengths were efficient for adjustment of milk yield at 90, 240, 270 and 305 days of lactation.

scholarly journals Genetic parameters of growth traits in Nellore cattle

2017 ◽  
Vol 38 (3) ◽  
pp. 1513
Author(s):  
Leandro Molina Kamei ◽  
Edson Luis De Azambuja Ribeiro ◽  
Nilva Aparecida Nicolao Fonseca ◽  
Carolina Amália De Souza Dantas Muniz ◽  
Tatiane Vito Camiloti ◽  
...  
Keyword(s):  
Genetic Correlation ◽  
Maternal Effects ◽  
Fixed Effects ◽  
Growth Traits ◽  
Correlation Coefficients ◽  
Correlated Response ◽  
Environmental Correlations ◽  
Nellore Cattle ◽  
Selection For ◽  
Heritability Estimates

This study evaluated non-genetic factors and calculated heritability estimates of direct and maternal effects for growth traits in Nellore cattle raised in southern Brazil. Performance records of 4170, 1538, 3139, 1830, and 1151 calves born from 2005 to 2011 were analyzed for birth weight (BW), adjusted120-day weight (W120), adjusted 205-day weight (W205), adjusted365-day weight (W365), and adjusted 550-day weight (W550), respectively. The components of (co)variance used to calculate heritability estimates were determined by Derivative-Free Restricted Maximum Likelihood using the MTDFREML software. Contemporary groups were included in the model as fixed effects, and direct and maternal effects, permanent environmental effects, and residual errors were included as random effects. Phenotypic correlations were estimated using the PROC CORR procedure from SAS. Overall means for BW, W120, W205, W365, and W550 were 38, 138, 201, 270, and 376 kg, respectively. Heritability estimates for direct and maternal effects were 0.17 ± 0.04 and 0.11 ± 0.03 (BW), 0.14 ± 0.03 and 0.03 ± 0.04 (W120), and 0.17 ± 0.04 and 0.09 ± 0.03 (W205). Genetic, phenotypic, and environmental correlations were 0.79, 0.44, and 0.32 for BW and W120, 0.79, 0.39, and 0.26 for BW and W205, and 0.96, 0.74, and 0.75 for W120 and W205. The results indicate that selection for pre-weaning weight would be more efficient using W205, and genetic correlation coefficients indicate that selection at any age should produce a positively correlated response at older ages. Genetic, phenotypic, and environmental correlation coefficients between W365 and W550 were 0.99, 0.75, and 0.76, respectively. Selection for adjusted 550-day weight should produce the greatest genetic gains. Genetic correlation coefficients between weight traits indicate that selection for weight at older ages, which could help reduce the number of weighings and increase accuracy of selection at younger ages, produces gains at older ages.

A genetic analysis of maternal behaviour score in Scottish Blackface sheep

2001 ◽  
Vol 72 (2) ◽  
pp. 415-425 ◽  
Author(s):  
N. R. Lambe ◽  
J. Conington ◽  
S. C. Bishop ◽  
A. Waterhouse ◽  
G. Simm
Keyword(s):  
Weight Gain ◽  
Genetic Analysis ◽  
Genetic Correlation ◽  
Genetic Control ◽  
Environmental Effect ◽  
Maternal Behaviour ◽  
Average Weight ◽  
Point Scale ◽  
Behaviour Score ◽  
First Time

AbstractUnder field conditions, ewe behaviour was quantified by maternal behaviour score (MBS)-a six-point scale which assesses ewe flight distance when lambs are handled for the first time, within 24 h of birth (adapted from O’Connor et al., 1985). MBS was measured on 847 Scottish Blackface ewes on two experimental hill farms, over a maximum of four parities. Live weights of lambs born to these ewes were measured at birth, marking (average age of 42 days) and weaning (average age of 120 days).MBS was significantly higher ( P < 0·05) for ewes with more lambing experience (multiparous ewes), for older ewes and for twin-bearing ewes compared with ewes with single lambs. MBS was under genetic control ( h2 = 0·13, permanent environmental effect = 0·19, when analysed as the same trait across parities) and the repeatability was 0·32.MBS had no significant effects on weight gain of lambs. However, a moderate, positive genetic correlation was estimated between MBS and the average weight gained by lambs from birth to marking ( rg = 0·4, s.e. 0·22), although the genetic correlation estimated between MBS and weight gained to weaning was close to zero ( rg = 0·02, s.e. 0·16). Ewes with a MBS of 1 (ewe flees and does not return to her lambs) had significantly more lambs dying before marking and weaning than ewes with a higher maternal behaviour score. Selection to reduce the proportion of ewes in this category may therefore be beneficial.

Genetic and epidemiological relationships between productivity and disease resistance: gastro-intestinal parasite infection in growing lambs

1999 ◽  
Vol 69 (3) ◽  
pp. 515-524 ◽  
Author(s):  
S. C. Bishop ◽  
M. J. Stear
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Food Intake ◽  
Genetic Correlation ◽  
Live Weight ◽  
Parasite Infection ◽  
Rate Reduction ◽  
Live Weight Gain ◽  
Faecal Egg Count ◽  
Selection For

AbstractThis paper demonstrates how interactions between host genotype for resistance to an infectious disease and the epidemiology of that disease can have large influences on animal productivity and hence on breeding goals for domestic livestock. This is illustrated for the case of gastro-intestinal parasitism in lambs. A model of the parasite infection was developed to include between-animal variation (genetic, permanent and temporary environmental) for live-weight gain, food intake, larval establishment rate in the host, worm fecundity and worm mortality rate. Achieved live-weight gain was defined as the sum of potential live-weight gain under conditions of no parasite infection, a trait correlated with food intake and growth-rate reduction due to the infection. The reduction in growth-rate was calculated from cumulative larval challenge and cumulative worm mass in the lamb. Genetic parameters were then estimated for the output traits of observed live weight at 6 months of age, growth rate reduction and faecal egg count. Model parameters were chosen so that the output means and heritabilities for faecal egg count and live-weight gain mimicked field data for Scottish Blackface lambs and growth-rate reductions were proportionately 0·25 , on average. The model predicted a weak phenotypic correlation (mean = -0·10) between observed live weight and faecal egg count, the indicator of resistance but a stronger favourable (negative) genetic correlation between these traits (mean = -0·27). The severity, or epidemiology, of the disease greatly influenced the results - the genetic correlation between observed live weight and faecal egg count strengthened from -0·02 to -0·46 as the disease severity changed from mild to severe. Selection for reduced faecal egg count resulted in large correlated increases in live-weight gain, more than twice that predicted by quantitative genetic theory, due to the reductions in growth rate losses as the disease challenge to the animals decreased. Conversely, selection for increased live-weight gain resulted in reductions in faecal egg count close to expectations. This asymmetry of selection response emphasizes the epidemiological benefits obtainable from selection for resistance to infectious chronic diseases - such selection will result in improvements in both animal health and productivity not seen when selection is for improved productivity, alone. Breeding goals should be designed to take account of such effects.

Pengaruh Penambahan Bungkil Kedelai terhadap Konsumsi Pakan, Pertambahan Bobot Badan Harian, dan Konversi Pakan pada Sapi Peranakan Simmental

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Rico Rico ◽  
Novi Eka Wati ◽  
Adisti Rastosari
Keyword(s):  
Weight Gain ◽  
Soybean Meal ◽  
Crude Protein ◽  
Dry Matter ◽  
T Test ◽  
Daily Weight Gain ◽  
Feed Consumption ◽  
Average Weight ◽  
Protein Consumption ◽  
Simmental Cattle

The objective of the researh was to study the effect of additions soybean meal in ration on the feed consumption, daily weight gain and feed convertion in Simmental cattle. The experiment used eight male Simmental cattle around 2 years old with an average weight of 198,65 ± 14,57 kilograms. The cattle kept for 35 days and given rations P0 (rations ranchers) and P1 (rations plus soybean meal). Data was obtained, then analyzed using independent sample t-test assisted with SPSS version 17.00 software. The result showed that the addition of soybean meal did not affect on dry matter consumption, daily weight gain, and feed convertion but, the crude protein consumption was increased. Keywords: dry matter consumption, daily weight gain, feed convertion

The co-responsibility of mass and environment in the formation of lenticular galaxies

2020 ◽  
Vol 15 (S359) ◽  
pp. 173-174
Author(s):  
A. Cortesi ◽  
L. Coccato ◽  
M. L. Buzzo ◽  
K. Menéndez-Delmestre ◽  
T. Goncalves ◽  
...  
Keyword(s):  
Active Galactic Nuclei ◽  
Maximum Likelihood Method ◽  
Spiral Galaxies ◽  
Galactic Nuclei ◽  
Rotation Velocity ◽  
Elliptical Galaxies ◽  
Likelihood Method ◽  
Data Set ◽  
Lenticular Galaxies ◽  
Galaxies Kinematics

AbstractWe present the latest data release of the Planetary Nebulae Spectrograph Survey (PNS) of ten lenticular galaxies and two spiral galaxies. With this data set we are able to recover the galaxies’ kinematics out to several effective radii. We use a maximum likelihood method to decompose the disk and spheroid kinematics and we compare it with the kinematics of spiral and elliptical galaxies. We build the Tully- Fisher (TF) relation for these galaxies and we compare with data from the literature and simulations. We find that the disks of lenticular galaxies are hotter than the disks of spiral galaxies at low redshifts, but still dominated by rotation velocity. The mechanism responsible for the formation of these lenticular galaxies is neither major mergers, nor a gentle quenching driven by stripping or Active Galactic Nuclei (AGN) feedback.

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