Biomaterial Database

Genetics statistics and relationships of teat and udder traits, somatic cell counts, and milk production. 1986

A J Seykora, and B T McDaniel

Teat lengths and diameters, udder clearance, cleft depth, and distances between teats were measured from 1967 to 1982 on Holstein cows. Numbers of observations per trait ranged from 5934 to 11,449. Cows were from six herds owned by the North Carolina Department of Agriculture and two research herds of North Carolina State University. Repeatabilities between adjacent lactations for physical traits of udder were mostly between .60 and .80. Repeatabilities between first and second lactations for average somatic cell count and mean log somatic cell count were .11 +/- .04 and .21 +/- .04. Heritabilities in first lactation were .63 for front teat length, .44 for teat diameter, .56 for rear udder clearance, .10 for cleft depth, .32 for mature equivalent milk, and .18 for somatic cell counts. Heritabilities of distances between teats ranged from .33 to .48. Cows with udder clearance higher from the ground, deeper clefts, smaller distances between teats, and teats of smaller diameter had lower somatic cell counts. Multiple regression analysis showed that dams' somatic cell counts and rear udder clearances were not significant predictors of daughters' somatic cell counts. Lactation average somatic cell counts of daughters were predicted with greater accuracy from averages of somatic cell counts of multiple lactations of dams than from single lactations of dams. Milk production and somatic cell counts seemed positively genetically correlated, more so in first than later lactations.

UI	MeSH Term	Description	Entries
D007774	Lactation	The processes of milk secretion by the maternal MAMMARY GLANDS after PARTURITION. The proliferation of the mammary glandular tissue, milk synthesis, and milk expulsion or let down are regulated by the interactions of several hormones including ESTRADIOL; PROGESTERONE; PROLACTIN; and OXYTOCIN.	Lactation, Prolonged,Milk Secretion,Lactations, Prolonged,Milk Secretions,Prolonged Lactation,Prolonged Lactations
D008321	Mammary Glands, Animal	MAMMARY GLANDS in the non-human MAMMALS.	Mammae,Udder,Animal Mammary Glands,Animal Mammary Gland,Mammary Gland, Animal,Udders
D008892	Milk	The off-white liquid secreted by the mammary glands of humans and other mammals. It contains proteins, sugar, lipids, vitamins, and minerals.	Cow Milk,Cow's Milk,Milk, Cow,Milk, Cow's
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
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
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