Effect of genetic and non-genetic factors on age at first calving in Sahiwal cattle

2016 ◽  
Author(s):  
Jitendra Singh ◽  
V. K. Singh ◽  
Alok Kumar Yadav ◽  
Amit Kumar Jha
Keyword(s):  
Statistical Model ◽  
Least Squares ◽  
Genetic Improvement ◽  
Fixed Effects ◽  
Genetic Factors ◽  
Uttar Pradesh ◽  
Heritability Estimate ◽  
Age At First Calving ◽  
Sahiwal Cows ◽  
Selection Of

The present study was conducted on Sahiwal cows maintained at Uttar Pradesh Livestock- cum- Agriculture Farm, Chak Ganjaria, Lucknow. A total of 1194 records on age at first calving (AFC) spanning over a period of 57 years (1949 to 2006) were subjected to least squares analysis using suitable statistical model considering sire as random while period and season as fixed effects. The least squares mean of AFC was estimated to be 1251.77± 22.15 days. The least squares analysis revealed significant effect (P £ 0.01) of sire and period. However, the effect of season was found to be non-significant. The heritability estimate of age at first calving was found to be 0.159. The genetic, phenotypic and environmental trend for AFC were -3.31, 32.78 and 36.09 respectively. It was concluded from the present findings that selection of sire may be practiced for genetic improvement of this trait and ameliorative managemental practices should be employed to improve upon the trait i.e. age at first calving.

Effect of genetic and non-genetic factors on lactation yield in Sahiwal cattle

2016 ◽  
Author(s):  
Jitendra Singh ◽  
V. K. Singh ◽  
Alok Kumar Yadav ◽  
Amit Kumar Jha
Keyword(s):  
Statistical Model ◽  
Least Squares ◽  
Milk Production ◽  
Genetic Factors ◽  
Uttar Pradesh ◽  
Breeding Values ◽  
Total Milk ◽  
Sahiwal Cattle ◽  
Sahiwal Cows

The aim of the present study was to evaluate the effect of genetic and non genetic sources of variations on lactation yield in Sahiwal cows maintained at Uttar Pradesh Livestock- cum- Agriculture Farm, Chak Ganjaria, Lucknow, U.P. Data comprising a total of 2985 records on lactation yield spanning over a period of 62 years (1949 to 2011) were analysed by least squares analysis using suitable statistical model. The overall least squares mean for total lactation yield was found to be 2069.2280.69 kg.Lactation yield was significantly influenced by sire (P<0.01), period of calving (P<0.01), season of calving (P<0.05) year and parity (P<0.05). The heritability for total milk production was estimated to be 0.105±0.035 and breeding values of sires ranged from − 121.38 to 103.69. Genetic, phenotypic and environmental trends for lactation yield were −4.46, −116.26 and −111.80, respectively.

Effect of non-genetic factors on weekly test day milk yield records in Holdeo cattle of marathwada region

2019 ◽  
Author(s):  
B.N. Thorat ◽  
B.M. Thombre
Keyword(s):  
Least Squares ◽  
Milk Yield ◽  
Genetic Factors ◽  
Age At First Calving ◽  
Cross Breeding ◽  
Calving Season

The data on weekly test day milk yield of 411 HF x Deoni crossbred having 838 weekly test day milk yield were collected from records maintained at Cattle Cross Breeding Project, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani (Maharashtra) over a period of 38 years (1977 to 2014). The least squares mean of weekly test day milk yield were estimated by considering effect of period of calving, season of calving and age at first calving group. The overall mean weekly test day milk yield varied from 1.35 ± 0.08 kg to 7.52 ± 0.08 kg recorded during 43rd and 6th week, respectively. The period of calving exerted significant (P less tahn 0.01) influence on all 43 weekly test day milk yield. The season of calving had significant (P less than 0.05) influence on WTDY5 to WTDY9, WTDY11 to WTDY13 and WTDY42 and WTDY43. However, non-significant effect observed in WTDY1 to WTDY4, WTDY10 and WTDY14 to WTDY41. The variation due to age at first calving group was significant (P less than 0.01) in WTDY3 to WTDY5 and, non-significant in rest of the weekly test day milk yield.

scholarly journals EFEITO DO MEIO E DA IDADE DA VACA SOBRE O GANHO DE PESO NA FASE DE CRIA, RECRIA E OS DIAS PARA SE OBTER 160 KG EM ANIMAIS DA RAÇA GUZERÁ

2004 ◽  
Vol 9 (1) ◽  
Author(s):  
E. GEMIN ◽  
J.C. SOUZA ◽  
L.O.C. SILVA ◽  
C.H.M. MALHADO ◽  
P.B. FERRAZ FILHO
Keyword(s):  
Environmental Factors ◽  
Statistical Model ◽  
Least Squares ◽  
Random Effects ◽  
Environmental Effects ◽  
Fixed Effects ◽  
Least Squares Method ◽  
Data Set ◽  
Quadratic Effect ◽  
Daily Gain

O objetivo deste trabalho foi avaliar a influência dos efeitos de meio e da idade da vaca sobre os ganhos de peso do nascimento ao desmame (GPD), período pós-desmame (GPS) e sobre o número de dias para se obter 160 kg (D160). O rebanho avaliado continha 1.747 animais, sendo os dados analisados pelo método dos quadrados mínimos utilizando-se um modelo estatístico contendo os efeitos fixos de mês, ano e sexo do bezerro, o efeito aleatório de touros na fazenda, e como covariável a idade da vaca ao parto. As médias ajustadas para ganho de peso pré e pós-desmame, e para dias para a obtenção 160 kg foram 0,604 ± 0,01 kg; 0,399 ± 0,01 kg; em 285 ± 5,3 dias, respectivamente. Os machos foram superiores às fêmeas relativo ao GPD = 6,0%; D160 = 5,8 %, GPS = 20,1%. Quanto ao mês, as maiores médias de ganho de peso no pré-desmame recaiu nos animais nascidos no mês de agosto. Com relação aos dias para se obter 160 kg, os melhores resultados foram dos animais nascidos nos meses julho a setembro. A idade da vaca influenciou as caracteristicas ganho de peso pré-desmame e no D160. Environmental effects and age of dam on pre- and post-weaning daily gain, and on number of days to gain 160 kg from birth to weaning on guzerath breed cattle Abstract The objective of this study was to evaluate the effects of environmental factors and age of dam on pre- (GPD) and post-weaning (GPS) daily gain, and on the were number of days to gain 160 kg (D160) from birth to weaning. The data set contained 1,747 animals, and were analyzed by the least squares method. The statistical model included the fixed effects of month and year of birth, and sex of the calf and age of the dam at calving. Sire nested within farm and the error were random effects. The pre- and post-weaning average daily gains, and days to gain 160 kg least squares means were 0.604 ± 0.01 kg, 0.399 ± 0.01 kg, and 285.0 ± 5.3 days, respectively. The males were 6.0, 21.1 and 5.8% superior to the females for GPD, GPS and D160, respectively. The highest pre-weaning gain was for the animals born August. Regarding D160, the best results were for the animals born from July to September. Age of the cow showed a significant quadratic effect on the traits. The best cows were the 94-month-old ones. First calving cows produced the lightest calves. The results showed the importance of the environmental effects on the traits studied, evidencing the need for them to be corrected.

scholarly journals Analysis of non-genetic factors affecting calving difficulty in the Czech Holstein population

2008 ◽  
Vol 53 (No. 7) ◽  
pp. 284-291 ◽  
Author(s):  
M. Fiedlerová ◽  
D. Řehák ◽  
M. Vacek ◽  
J. Volek ◽  
J. Fiedler ◽  
...  
Keyword(s):  
Fixed Effects ◽  
Genetic Factors ◽  
Management Tool ◽  
Gestation Length ◽  
Calving Interval ◽  
Data Set ◽  
Age At First Calving ◽  
Factors Affecting ◽  
Calving Difficulty ◽  
Holstein Population

The objective of this study was to analyze the effects of non-genetic factors affecting calving difficulty in the Holstein population of the Czech Republic for subsequent compilation of the model for genetic evaluation as well as for herd management practice. Calving difficulty recorded in 1997–2006 was assessed in three categories: 1 = normal, 2 = hard pull, 3 = complicated. The original observations were transformed to an underlying normal scale. A data set containing 409 255 records was analysed by a linear model with fixed effects of season, parity of dam, sex of calf and Holstein gene proportion. All these effects were significant, and their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and preceding calving interval were performed. The results revealed that gestation length was in a non-linear relationship with calving difficulty. A higher risk of difficult calving was associated with short or long gestation and with a prolonged preceding calving interval in multiparous cows. Calving difficulty should be adjusted for these factors. A decreased risk of difficult calving could be achieved by an altering of calving interval and age at first calving as a management tool.

scholarly journals Growth Performance of Purgi Goats under Field Conditions in Kargil District (Ladakh)

2021 ◽  
Author(s):  
Safeer Alam ◽  
Mubashir Ali Rather ◽  
Nusrat Nabi ◽  
Gurjeet Kaur ◽  
S. Shanaz ◽  
...  
Keyword(s):  
Body Weight ◽  
Growth Performance ◽  
Least Squares ◽  
Fixed Effects ◽  
Genetic Factors ◽  
Growth Traits ◽  
Fibre Production ◽  
Season Of Birth ◽  
Coefficients Of Variations ◽  
Birth Type

Background: Purgi goats are native to Ladakh. They are used for fibre production and are known for the quality chevon. A study was, therefore, undertaken to study the effect of non-genetic factors on growth traits of Purgi Goats in its breeding tract. Methods: Flocks of 80 farmers from 8 villages of district Kargil were monitored to collect the data pertaining to growth traits during 2017 and 2018. The data so collected were suitably classified to study the major fixed effects like birth year, kid, parity of dam, season of birth and type of birth. Result: The averages were1.21±0.02, 3.62±0.02, 5.82±0.02, 8.73±0.03, 10.71±0.04 and 13.49±0.09 for BW, WW, 6MW, 9MW, 12MW and 18MW, respectively. The coefficients of variations of all the traits were low. Highest variability of 13.49 was observed for 18MW. The values of least squares means (LSM’s) of 0.96±0.05, 3.74±0.03, 5.80±0.05, 8.74±0.06, 10.87±0.08 and 13.91±0.19 for birthweight (BW), weaning weight (WW), six months body weight (6MW), nine months weight (9MW), yearling body weight (12MW) and eighteen months (18MW) weight were observed in the present study. The effects of sex of kids, season of birth and year of birth were significant (p less than 0.05) on all traits under study, whereas effect of birth-type was significant (p less than 0.05) on BW and WW and effect of parity was non-significant on all traits under study. All the traits BW, WW and 6MW were positively correlated among themselves. The correlations ranged from low (between BW and WW ) to high (WW with 9MW and 12MW).

scholarly journals Genetic parameters estimates for gestation length in beef cattle

2005 ◽  
Vol 57 (6) ◽  
pp. 784-791 ◽  
Author(s):  
J.C.M.C. Rocha ◽  
H. Tonhati ◽  
M.M. Alencar ◽  
R.B. Lôbo
Keyword(s):  
Beef Cattle ◽  
Variance Components ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
Genetic Effect ◽  
Heritability Estimate ◽  
Gestation Length ◽  
Phenotypic Variance ◽  
Fitting Model ◽  
Selection Of

Variance components were estimated for gestation length fitting the additive direct effect of calf, maternal genetic effect and sire effect as random effects. The statistical models also included the fixed effects of contemporary group, that included the date of breeding (AI), date of birth, and sex of calf, and the covariate age of dam at calving (linear and quadratic). Two different models were used, model 1 considering GL as a trait of the calf, and model 2 considering GL as a trait of the dam. The means of gestation length for the purebred animals were 294.55 days (males) and 293.34 days (females), while for the crossbred animals they were 292.49 days (males) and 292.55 days (females). Variance components for the purebred animals, fitting model 1, were 14.47, 72.78 and 57.31, for the additive genetic (sigma2a), total phenotypic (sigma2p) and residual (sigma2e) effects, respectively, with a heritability estimate of 0.21. For the crossbred animals, variance components for sigma2a, sigma2p, sigma2e were 90.40, 127.35 and 36.95, respectively, with a heritability of 0.71. Fitting model 2, the estimated variance components for the purebred animals were 12.78, 5.01, 74.84 and 57.05 for sigma2a , sire of calf (sigma ²asire), sigma2p, and sigma2e , respectively. The sire effect accounted for 0.07 (c²) of the phenotypic variance and the coefficient of repeatability was 0.17. For the crossbred animals, the variance components were 22.11 (sigma2a ), 22.97 (sigma ²asire ), 127.70 (sigma2p) and 82.61 (sigma2e), while c² was 0.18 and repeatability was 0.17. Therefore, regarding selection of beef cattle, it is suggested to use the heritability estimate obtained by model 1, where GL is considered as a trait of the calf.

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

2017 ◽  
Vol 155 (4) ◽  
pp. 679-687 ◽  
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.

Bridging the Gap between Quantitative and Qualitative Historical Research: an application of multiple regression analysis and homogeneity analysis with alternating least squares

1996 ◽  
Vol 8 (3) ◽  
pp. 133-144 ◽  
Author(s):  
María del Mar del Pozo Andrés ◽  
Jacques F A Braster
Keyword(s):  
Least Squares ◽  
Multiple Regression ◽  
Historical Research ◽  
Alternating Least Squares ◽  
Categorical Variables ◽  
Two Dimensional ◽  
Homogeneity Analysis ◽  
Regression Approach ◽  
Dimensional Picture ◽  
Selection Of

In this article we propose two research techniques that can bridge the gap between quantitative and qualitative historical research. These are: (1) a multiple regression approach that gives information about general patterns between numerical variables and the selection of outliers for qualitative analysis; (2) a homogeneity analysis with alternating least squares that results in a two-dimensional picture in which the relationships between categorical variables are graphically presented.

The antecedents of corporate social and environmental responsibility discourse in Pakistan: Multiple theoretical perspectives

2019 ◽  
Author(s):  
Muhammad Farhan Basheer ◽  
Saqib Muneer ◽  
Muhammad Atif ◽  
Zubair Ahmad
Keyword(s):  
Institutional Theory ◽  
Least Squares ◽  
Agency Theory ◽  
Stakeholder Theory ◽  
Fixed Effects ◽  
Ordinary Least Squares ◽  
Environmental Responsibility ◽  
Legitimacy Theory ◽  
Discourse Practices ◽  
Corporate Social

The primary purpose of the study is to explore the antecedents of corporate social and environmental responsibilities discourse practices in Pakistan. The industry sensitivity, government shareholding, block holder ownership, print media coverage, environmental monitoring programs, and strategic posture are examined as antecedents of corporate social and environmental responsibility practices. A multidimensional theoretical perspective namely stakeholder theory (ST), institutional theory (IT), agency theory (PAT), and legitimacy theory (LT) is used to conceptualize the phenomena. All the four of perspective theories (positive accounting theory, legitimacy theory, stakeholder theory, and institutional theory) claim that there are ‘pressures’ that impact the organization. How much ‘pressures’ are recognized, managed or satisfied differs from one perspective of theory to the other. To estimate the data, this study uses three sets of panel data models, i.e., the pooled ordinary least squares model (POLS) or constant coefficients model, fixed effects (FEM or least squares dummy variable/LSDV model) and random-effects models. The final sample is comprising of 173 firms over eight years from 2011 to 2017. The firms listed in PSX are included in the sample. Overall the findings of the study have shown agreement with the proposed results. However, the study has provided more support to the institutional theory and stakeholder theory. Keywords: Corporate Social Responsibility, Stakeholders Theory, Agency Theory, Pakistan

Caracterização da Peneira Média em Clones de Coffea canephora

REVISTA FIMCA ◽  
2018 ◽  
Vol 5 (2) ◽  
pp. 28-31
Author(s):  
Darlan Darlan Sanches Barbosa Alves ◽  
Victor Mouzinho Spinelli ◽  
Marcos Santana Moraes ◽  
Carolina Augusto De Souza ◽  
Rodrigo da Silva Ribeiro ◽  
...  
Keyword(s):  
Genetic Improvement ◽  
Block Design ◽  
Coffea Canephora ◽  
Coffee Production ◽  
Randomized Block Design ◽  
Significant Difference ◽  
The Mean ◽  
Four Blocks ◽  
Selection Of

Introdução: O estado de Rondônia se destaca como tradicional produtor de café, sendo o segundo maior produtor brasileiro de C. canephora. No melhoramento genético de C. canephora, a seleção de plantas de elevada peneira média está associada à bebida de qualidade superior. Objetivos: O objetivo desse estudo foi avaliar a variabilidade genética de clones de C. canephora para o tamanho dos grãos, mensurado a partir da avaliação da peneira média (PM). Materiais e Métodos: Para isso, foi conduzido ao longo de dois anos agrícolas experimento no campo experimental da Embrapa no município de Ouro Preto do Oeste-RO, para a avaliação da peneira média de 130 genótipos (clones) com características das variedades botânicas Conilon, Robusta e híbridos intervarietais. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições de quatro plantas por parcela. Resultados: Não houve resultados significativos para a interação clones X anos, indicando uma maior consistência no comportamento das plantas ao longo do tempo. Porém foram observadas diferenças significativas para o tamanho dos grãos entre os genótipos avaliados, possibilitando selecionar genótipos superiores. Conclusão: Os genótipos agruparam-se em cinco classes de acordo com o teste de média, subsidiando a caracterização de um gradiente de variabilidade da característica avaliada ABSTRACTIntroduction: Coffea canephora accounts for approximately 35% of the world's coffee production. The state of Rondônia stands out as a traditional coffee producer, being the second largest Brazilian producer of C. canephora. In the classical genetic improvement of C. anephora, the selection of plants of high average sieve is associated with a drink of superior quality. Objectives: The objective of this udy was to evaluate the genetic variability of Coffea canephora clones for the agronomic medium sieve (PM). Materials and Methods: The experiment was conducted in the experimental field of Embrapa, municipality of OuroPreto do Oeste-RO, located at coordinates 10º44'53 "S and 62º12'57". One hundred thirty genotypes (clones) of botanical characteristics Conilon, Robusta and intervarietal hybrids were evaluated in the agricultural years 2013-2014 and 2014-2015. The experimental design was a randomized block design with four blocks and four plants per plot, spacing 3.5 x 1.5 meters between plants. Results: Significant difference was found for the grain size. According to the F test, at 5% probability, the genotypes were grouped into five classes according to the mean test. Conclusion: The results obtained subsidized the characterization of a variability gradient of the evaluated trait.

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