Association of polymorphism of the β(1, 4)-galactosyltransferase-I gene with milk production traits in Holsteins.

The β(1,4)-galactosyltransferase-I gene (β4galt1) encodes the catalytic part of the enzyme lactose synthase, responsible of lactose synthesis in the mammary gland. The complete coding region of the gene was screened for the presence of allelic variation among a sample of 1,200 Iranian Holstein cows, using PCR-SSCP technique followed by sequencing. Nine polymorphic nucleotide sites were identified-one in exons I and VI, two in exons II and III, and three in exon V.

Associations among milk production traits and glycosylated haemoglobin in dairy cattle; importance of lactose synthesis potential.

Glucose is the major precursor of lactose synthesis in the mammary gland. Lactose the major carbohydrate and osmolyte of milk, controls milk volume and its concentration. Glycosylated haemoglobin (HbG) is a retrospective measure of mean blood glucose level and it is largely unaffected by recent physiological conditions and environmental events.

Distribution of the enzyme rhodanese in tissues of the cat (Felis catus).

The enzyme rhodanese (EC 2.8.1.