Effect of positive genetic trend for mature size on age-of-dam adjustment factors for weaning weight in Angus field records. 1994

S L Northcutt, and D E Wilson, and J A Hoekstra
Department of Animal Science, Iowa State University, Ames 50011.

Weaning weight and postweaning gain field data from the American Angus Association were used to estimate age-of-dam adjustment factors for 205-d weaning weight. A two-trait model was used to take into account all genetic information available in the breed. Correction factors were developed for age-of-dam categories by sex of calf and management (creep or no creep) within maternal-grandsire birth-year groups. The maternal-grandsire birth-year groups were included to determine the need for updating age-of-dam adjustment factors for weaning weight. The mathematical model for 205-d weight included an overall mean, weaning contemporary group, age of dam by sex of calf and management code within maternal-grandsire birth-year group, animal direct effect, maternal genetic effect, permanent environmental effect, and residual error. The model for postweaning gain included an overall mean, postweaning contemporary group, animal direct effect, and residual error. Age-of-dam additive adjustment factors differed from the current factors used for the Angus breed. Young dams did not receive as large an adjustment as the current Angus adjustments recommended. Grouping the age-of-dam categories by birth year of maternal grandsire yielded different additive adjustment factors for 205-d weight. Noncreep calves tended to have larger age-of-dam adjustments than creep-fed calves did. Results indicate the need to consider including age of dam as a fixed effect in the animal model evaluation, so that adjustment factors may be specific to the genetic changes for growth in the breed.

UI MeSH Term Description Entries
D008297 Male Males
D001835 Body Weight The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms. Body Weights,Weight, Body,Weights, Body
D002417 Cattle Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor. Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D005260 Female Females
D000367 Age Factors Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time. Age Reporting,Age Factor,Factor, Age,Factors, Age
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D000821 Animal Feed Foodstuff used especially for domestic and laboratory animals, or livestock. Fodder,Animal Feeds,Feed, Animal,Feeds, Animal,Fodders
D000822 Animal Husbandry The science of breeding, feeding and care of domestic animals; includes housing and nutrition. Animal Husbandries,Husbandries, Animal,Husbandry, Animal
D012737 Sex Factors Maleness or femaleness as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or effect of a circumstance. It is used with human or animal concepts but should be differentiated from SEX CHARACTERISTICS, anatomical or physiological manifestations of sex, and from SEX DISTRIBUTION, the number of males and females in given circumstances. Factor, Sex,Factors, Sex,Sex Factor
D014886 Weaning Permanent deprivation of breast milk and commencement of nourishment with other food. (From Stedman, 25th ed) Weanings

Related Publications

S L Northcutt, and D E Wilson, and J A Hoekstra
March 2004, Genetics and molecular research : GMR,
S L Northcutt, and D E Wilson, and J A Hoekstra
August 1996, Journal of animal science,
S L Northcutt, and D E Wilson, and J A Hoekstra
September 2011, Journal of animal science,
S L Northcutt, and D E Wilson, and J A Hoekstra
March 1999, Journal of animal science,
S L Northcutt, and D E Wilson, and J A Hoekstra
August 1991, Journal of animal science,
S L Northcutt, and D E Wilson, and J A Hoekstra
December 1999, Journal of animal science,
Copied contents to your clipboard!