Genetic parameters and non-genetic influences related to birth weight in farmed white-tailed deer

SUMMARYStudying and understanding the sources of variation in early life traits in farmed deer are fundamental for management and/or breeding purposes. Data from a captive white-tailed deer population were analysed to identify non-genetic and genetic factors affecting the birth weight (BW) of fawns. The year, type of birth and sex were included in a fixed linear model to examine their significance. All of the examined non-genetic factors had a highly significant effect on BW (P<0·001). The examined years showed variation attributed to food availability affecting the gestational conditions of does. Male fawns were 193 g heavier than female fawns at birth (P<0·001), and singleton births were associated with a higher BW (2·97±0·043 kg) compared with twin (−0·261 g) and triplet (−0·642 g) fawning (P<0·001). The best-fitting animal model was selected by comparing reduced and complete models. Based on the selected animal model, which included direct genetic and common maternal effects, genetic components and parameters were estimated. The direct heritability was found to be 0·28±0·126, and a small but important contribution of common maternal environmental effects was identified (c2=0·15±0·062). The results support the importance of certain environmental factors affecting BW and indicate the relevance of direct genetic and maternal environmental influences to sustained genetic changes in BW and positively correlated traits in farmed white-tailed deer populations.

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Genetic and Non-Genetic Factors Affecting Reproductive Traits of Pakhribas Pig in Nepal

Nepal Agriculture Research Journal ◽

10.3126/narj.v8i0.11584 ◽

2014 ◽

Vol 8 ◽

pp. 77-81

Author(s):

Shreeram P. Neopane

Keyword(s):

Genetic Parameters ◽

Genetic Factors ◽

Agricultural Research ◽

Reproductive Traits ◽

Gestation Length ◽

Research Station ◽

Season Of Birth ◽

Factors Affecting ◽

The People ◽

Sources Of Variation

Pakhribas pig is a black colour pig and is highly preferred by the people in the Eastern hills of Nepal. This breed was developed in Nepal by three-way crossing of exotic breeds (Saddle back, Fayuen and Tamworth) at Agricultural Research Station (ARS), Pakhribas, the then Pakhribas Agricultural Centre (PAC). The data of 348 pigs, born over a period of fifteen years (1990 to 2004) were used to study the effect of non-genetic factors on reproductive traits and estimate their genetic parameters. The findings revealed that the overall gestation length and farrowing intervals were 113.7 ± 0.12 days and 182.5 ± 2.2 days, respectively. Season of birth and parity of dams were not important sources of variation for reproductive traits, where as year affected these traits significantly. Heritability estimates of gestation length was low (0.02 ± 0.094), but heritability for farrowing interval was moderate (0.14 ± 0.147) suggesting selection based on farrowing interval would bring the improvement in the trait.Nepal Agric. Res. J. Vol. 8, 2007, pp. 77-81DOI: http://dx.doi.org/10.3126/narj.v8i0.11584

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Comparison of models for estimating genetic parameters and predicting breeding values for birth weight and calving ease in Czech Charolais cattle

Czech Journal of Animal Science ◽

10.17221/7529-cjas ◽

2014 ◽

Vol 59 (No. 7) ◽

pp. 302-309 ◽

Cited By ~ 2

Author(s):

L. Vostrý ◽

Z. Veselá ◽

A. Svitáková ◽

H. Vostrá Vydrová

Keyword(s):

Animal Model ◽

Birth Weight ◽

Beef Cattle ◽

Fixed Effects ◽

Genetic Parameters ◽

Genetic Correlations ◽

Genetic Effects ◽

Parameters Estimation ◽

Calving Ease ◽

Heritability Estimates

The most appropriate model for genetic parameters estimation for calving ease and birth weight in beef cattle was selected. A total of 27 402 field records were available from the Czech Charolais breed. For estimation of genetic parameters for calving ease and body weight, three bivariate models were tested: a linear-linear animal model (L-LM) with calving ease classified into four categories (1 – easy; 2–4 – most difficult), a linear-linear animal model (SC-LM) in which calving ease scores were transformed into Snell scores (Snell 1964) and expressed as percentage of assisted calving (ranging 0–100%), and a bivariate threshold-linear animal model (T-LM) with calving ease classified into four categories (1 – easy, 2–4 – most difficult). All tested models included fixed effects for contemporary group (herd × year × season), age of dam, sex and breed of a calf. Random effects included direct and maternal genetic effects, maternal permanent environmental effect, and residual error. Direct heritability estimates for calving ease and birth weight were, with the use of L-LM, SC-LM, and T-LM, from 0.096 ± 0.013 to 0.226 ± 0.024 and from 0.210 ± 0.024 to 0.225 ± 0.026, respectively. Maternal heritability estimates for calving ease and birth weight were, with the use of L-LM, SC-LM, and T-LM, from 0.060 ± 0.031 to 0.104 ± 0.125 and from 0.074 ± 0.041 to 0.075 ± 0.040, respectively. Genetic correlations of direct calving ease with direct birth weight ranged from 0.46 ± 0.06 to 0.50 ± 0.06 for all tested models; whereas maternal genetic correlations between these two traits ranged from 0.24 ± 0.17 to 0.25 ± 0.53. Correlations between direct and maternal genetic effects within-trait were negative and substantial for all tested models (ranging from –0.574 ± 0.125 to –0.680 ± 0.141 for calving ease and from –0.553 ± 0.122 to –0.558 ± 0.118 for birth weight, respectively), illustrating the importance of including this parameter in calving ease evaluations. Results indicate that any of the tested models could be used to reliably estimate genetic parameters for calving ease for beef cattle in the Czech Republic. However, because of advantages in computation time and practical considerations, genetic analysis using SC-LM (transformed data) is recommended.

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Estimates of phenotypic and genetic parameters for birth weight of Brown Swiss calves in Turkey using an animal model

Tropical Animal Health and Production ◽

10.1007/s11250-011-0036-6 ◽

2011 ◽

Vol 44 (5) ◽

pp. 1027-1034 ◽

Cited By ~ 1

Author(s):

A. Sahin ◽

Z. Ulutas ◽

A. Yilmaz Adkinson ◽

R. W. Adkinson

Keyword(s):

Animal Model ◽

Birth Weight ◽

Genetic Parameters ◽

Brown Swiss

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Factors affecting reproductive performance and estimates of genetic parameters of litter size in Horro sheep

The Journal of Agricultural Science ◽

10.1017/s0021859602002265 ◽

2002 ◽

Vol 139 (1) ◽

pp. 79-85 ◽

Cited By ~ 13

Author(s):

S. ABEGAZ ◽

G. DUGUMA ◽

E. NEGUSSIE ◽

U. GELMESA ◽

F. TEREFE ◽

...

Keyword(s):

Animal Model ◽

Litter Size ◽

Age Structure ◽

Reproductive Performance ◽

Genetic Improvement ◽

Genetic Parameters ◽

Factors Affecting ◽

Optimal Weight ◽

Annual Means ◽

Lambing Rate

Conception and lambing rate, and litter size were studied on data from a flock of Horro sheep. The CATMOD and GLM procedures of SAS were used for the analysis of these traits. A sire, direct additive genetic and a repeatability animal model were employed to obtain estimates of heritability and repeatability for litter size. The results obtained showed that year of mating, age and weight of ewes at mating and number of previous parities had significantly (P<0.01) affected the rate of conception and lambing while weight of rams at mating has shown no significant effect (P>0.05). An increase in both conception and lambing rates was observed with the increase in weight of ewes up to about 36 kg and declined thereafter. Ewes which previously had no or one parity had lower conception and lambing rates compared with ewes in later parities. However, a decline in both conception and lambing rates was also observed in old ewes. Year of lambing, parity and weight of ewes at mating had a highly significant (P<0.01) effect on litter size. The overall mean litter size in the flock was 1.34 with annual means ranging from 1.18 to 1.55. Litter size increased with parity from 1.26 in primiparous ewes to 1.44 for ewes of parities five and above. With respect to weight of ewes at mating, litter size increased by 2.5% for each kg increase in weight at mating. The estimates of direct heritability (h2) for litter size were 0.17, 0.11 and 0.06 under the sire, direct animal and repeatability models. Repeatability was estimated to be 0.12. Since heritability and repeatability estimates of litter size are low, genetic improvement by selection may not bring sizeable impact in increasing litter size. Therefore flock management for optimal age structure and optimal weight of ewes at mating should receive due consideration to improve rates of conception, lambing and litter size in Horro sheep.

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Erratum to: Estimates of phenotypic and genetic parameters for birth weight of Brown Swiss calves in Turkey using an animal model

Tropical Animal Health and Production ◽

10.1007/s11250-012-0214-1 ◽

2012 ◽

Vol 44 (7) ◽

pp. 1815-1815

Author(s):

A. Sahin ◽

Z. Ulutas ◽

A. Yilmaz Adkinson ◽

R. W. Adkinson

Keyword(s):

Animal Model ◽

Birth Weight ◽

Genetic Parameters ◽

Brown Swiss

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Heritability of embryonic mortalities in ostrich eggs and factors affecting hatching failure of fertile eggs during artificial incubation

Animal Production Science ◽

10.1071/an11225 ◽

2012 ◽

Vol 52 (9) ◽

pp. 806 ◽

Cited By ~ 1

Author(s):

Z. Brand ◽

S. W. P. Cloete ◽

I. A. Malecki ◽

C. R. Brown

Keyword(s):

Genetic Parameters ◽

Embryonic Mortality ◽

High Rate ◽

Industry Data ◽

Genetic Changes ◽

Factors Affecting ◽

Early Embryonic Mortality ◽

The Individual ◽

Embryonic Death ◽

Artificial Incubation

The high rate of embryonic mortality during artificial incubation of ostrich eggs is a major concern in the ostrich industry. Data from 48 126 individual egg records were available to derive genetic parameters for embryonic mortalities, modelled as a trait of the individual egg. Embryonic mortality was classified according to stage of death, i.e. early embryonic mortality that occurred before 21 days of incubation (EEM), late embryonic mortality that occurred after 21 days of incubation (LEM) and overall embryonic mortalities (OEM). LEM increased significantly for eggs laid by females >10 years old. Transfer of eggs between incubators during incubation also impaired hatchability. An increase in OEM occurred for eggs freshly set (43%) as well as for eggs stored for more than 6 days (50%). Medium heritability (h2) estimates were derived for all the embryonic death traits and ranged between 0.16 ± 0.02 for LEM and 0.22 ± 0.03 for EEM. The dam permanent environmental effect was low ranging between 0.021 ± 0.005 for LEM and 0.046 ± 0.008 for EEM. Hatchability of fertile ostrich eggs may consequently be improved by removing older females from breeding flocks, setting of eggs between 2 and 6 days after collection, and by refraining to transfer of eggs between incubators during incubation. Moderate h2 estimates indicate that breeding may be used as a tool to enhance chick production in ostriches. This contention is supported by the fact that selected breeding for chick production and liveweight appeared to result in genetic changes in embryonic mortality rates.

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Parámetros genéticos y tendencias para características de crecimiento en el ganado criollo sanmartinero en los Llanos Orientales de Colombia

Ciencia y Tecnología Agropecuaria ◽

10.21930/rcta.vol10_num2_art:142 ◽

2009 ◽

Vol 10 (2) ◽

pp. 196 ◽

Cited By ~ 1

Author(s):

Rodrigo Martínez ◽

Guillermo Onofre ◽

Nelson Polanco

Keyword(s):

Animal Model ◽

Birth Weight ◽

Environmental Effects ◽

Genetic Parameters ◽

Growth Traits ◽

Genetic Change ◽

Direct Effects ◽

Creole Cattle ◽

Maternal Heritability ◽

Daily Gain

El objetivo de este trabajo fue estimar parámetros genéticos para características de crecimiento y la tendencia de sus valores genéticos en una población de la raza bovina criolla sanmartinero, localizada en el departamento del Meta, Colombia. Se utilizó un modelo animal con efectos directos, maternos y de ambiente permanente y se analizaron las características peso al nacimiento (PN), peso al destete (PD) (ajustado a 240 d.), peso a los 16 meses (P16m), ganancia diaria de peso al destete (GPD) y ganancia diaria de peso desde el destete a los 16 meses (GP16m). Se analizaron 2.812 registros productivos de animales y se encontraron valores de heredabilidad directa moderados, variando desde 0,16 hasta 0,37 para GP16m y GPD respectivamente. Los valores de heredabilidad directa siempre fueron mayores que los de heredabilidad materna y los efectos de ambiente permanente variaron entre 0,024 ± 0,033 para PN hasta 0,067 ± 0,041 para P16m; los valores de repetibilidad fueron superiores para las características de PD (0,41) y GPD (0,37). Los valores genéticos anuales promedio para los efectos directos presentaron en general valores positivos, lo que muestra una tendencia creciente aunque con una alta variación a través de los años; por su parte, los valores genéticos maternos anuales promedio presentaron valores cercanos a cero, aunque en general su tendencia también fue creciente. A pesar de tratarse de un núcleo de conservación, donde no se ha dado selección para estas características, se encontró una tendencia genética que indica un cambio genético positivo. Genetic parameters and trends for growth traits in creole cattle sanmartinero in the eastern savannas in Colombia The aim of this work was to estimate the genetic parameters for growth traits and the tendency of their genetic values in a population of Bovine Creole cattle Sanmartinero, located in Meta, Colombia. Was used an animal model with direct and maternal effects as well as a permanent environmental effects and were analyzed birth weight, weaning weight, (adjusted at 240 d), weight at 16 months, weaning daily gain, and daily gain at 16 months. Were analyzed a total of 2812 productive records from animals and were found direct heritability moderate values, ranging between from 0.16 to 0.3 for GP16m and GP respectively. The direct heritability values always were higher than the maternal heritability values and the permanent environmental effects ranged between 0.024 ± 0.033 for PN until 0.067 ± 0.041 for P16m, but the repeatability values were higher for PD (0.41) and GPD (0.37) traits. With reference to the tendency of average yearly genetic values for direct effects, always displayed positive values and a increase tendency however a high variation between the years were found, conversely to the genetic maternal values than displayed generally values near to zero, but their tendency also was to increase. Is noteworthy than in spite of to be a conservation herd, than do not has been used for selection programs for those traits, was found a genetic tendency that suggest a positive genetic change.

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Non-Genetic Factors Affecting Birth Weight in the Lambs of Blackheads Pleven Breed

Journal of Animal Science Advances ◽

10.5455/jasa.20150326081131 ◽

2015 ◽

Vol 5 (3) ◽

pp. 1208 ◽

Cited By ~ 1

Author(s):

Miroslav Simeonov ◽

David Harmon ◽

Krym Nedelkov

Keyword(s):

Birth Weight ◽

Genetic Factors ◽

Factors Affecting

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Genetic and non-genetic factors affecting post-weaning survivability in goats

Animal Science ◽

10.1017/s0003356100020122 ◽

1991 ◽

Vol 53 (2) ◽

pp. 199-202 ◽

Cited By ~ 3

Author(s):

D. K. Singh ◽

C. S. P. Singh ◽

H. R. Mishra

Keyword(s):

Overall Survival ◽

Birth Weight ◽

Survival Rate ◽

Linear Relationship ◽

Genetic Factors ◽

Survival Rates ◽

Factors Affecting ◽

Positive Linear Relationship ◽

Filial Generation ◽

Overall Survival Rates

AbstractGenetic and non-genetic factors affecting survival during the post-weaning period from 3 to 12 months of age were assessed in 823 kids (217 Black Bengal, 410 Jamunapari × Black Bengal and 196 Beetal × Black Bengal) born during 1981-86. The overall survival rates during 3 to 6 and 6 to 12 months of age were 79·22 (s.e. 4·06) and 82·02 (s.e. 5·49)% respectively. Variation in survival rate during 3 to 6 months of age was significant due to season of their birth (P < 0·01) and birth weight (P < 0·05). Survival rate during 6 to 12 months of age varied due to genetic group (P < 0·01), sex (P < 0·05) and birth weight (P < 0·05). Type of birth (litter size), dam's weight at kidding and filial generation had no significant effect on survival rate during the post-weaning period. Birth weight of kids had a positive linear relationship with their survivability during post-weaning period. Summer-born kids had significantly lower survival rates from 3 to 6 months of age compared with those born in the winter and monsoon periods. Heritability estimates for survival rates during the post-weaning period were not significantly different from zero.

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Evaluación genética del comportamiento productivo y reproductivo en núcleos de conejos de las razas Nueva Zelanda y Chinchilla

Ciencia y Tecnología Agropecuaria ◽

10.21930/rcta.vol8_num1_art:86 ◽

2007 ◽

Vol 8 (1) ◽

pp. 69

Author(s):

Rodrigo Vásquez ◽

Rodrigo Martínez ◽

Carlos Manrique ◽

Yenny Rodríguez

Keyword(s):

New Zealand ◽

Analysis Of Variance ◽

Reproductive Behavior ◽

Genetic Parameters ◽

Genetic Factors ◽

Genetic Progress ◽

Selection Program ◽

Litter Weight ◽

Individual Weight ◽

Sources Of Variation

Se realizaron análisis de varianza y estimaciones de heredabilidad y repetibilidad para características de crecimiento, reproducción y sobrevivencia en dos núcleos de conejos de las razas Nueva Zelanda (NZ) y Chinchilla (Ch), a partir de registros sobre montas y destetes realizados a lo largo de cinco años. Entre los caracteres analizados, los factores genéticos derivados de padre y madre, así como los ambientales, constituyeron fuentes significativas de variación especialmente en la fase de cría. En cuanto las estimaciones de los parámetros genéticos, se alcanzaron valores de heredabilidad de h2= 0,00 y h2= 0,33 para los caracteres ‘peso individual al parto’ e ‘intervalo entre partos’, respectivamente en la población NZ; y de h2= 0,00 para ‘peso individual al parto’ y ‘peso camada viva al parto’ y h2= 0,40 para ‘intervalo entre partos’ en la población Ch. Se determinó que las características en la fase de cría tienden a presentar mayores valores de heredabilidad que las relacionadas con la etapa de engorde, pues los índices de heredabilidad encontrados para los caracteres ‘peso al sacrificio’, ‘peso de la canal’ y ‘rendimiento en canal’ son bajos (menores de 0,11), por lo que su inclusión en un programa de selección tendría bajo impacto sobre el progreso genético. Genetic evaluation of production and reproductive behavior in clusters of New Zealand and Chinchilla races of rabbitsAnalysis of variance and estimates of heritability and repeatability for characteristics of development, reproduction and survivorship in two clusters of New Zealand (NZ) and Chinchilla (Ch) races of rabbits were determined from registries about matings and weanings throughout a five year period. Among the characteristics analyzed, genetic factors derived from father and mother, as well as the environmental, constituted significant sources of variation, especially during the rearing phase. In regard to the estimations of genetic parameters, values of heritability were reached that varied between h2= 0.00 and h2= 0.33 for the characters ‘individual weight at birth’ and ‘interval between births’, respectively, for the NZ race; and between h2= 0.00 for ‘individual weight at birth’ and ‘live litter weight at birth’ and h2= 0.40 for ‘interval between births’ in the Ch population. It was determined that the characteristics during the rearing phase tend to show higher values of heritability than those related to the fattening stage, in which the heritability indices found for the characters ‘weight at sacrifice’, ‘slaughter weight’ and ‘slaughter yield’ are low (less than 0.11), so their inclusion in a selection program would have low impact on genetic progress.

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