Lactoferrin concentration and expression in New Zealand cows milked once or twice a day

Anim Sci J. 2020 Jan-Dec;91(1):e13331. doi: 10.1111/asj.13331.

Abstract

This study evaluated the concentration and expression of lactoferrin (LF) in cows selected for once a day (OAD) milking compared to twice a day (TAD) milking. Milk samples were collected from the Massey University TAD and OAD herds. Milk traits and expression of LF and insulin-like growth factor 1 (IGF-1) were analyzed with a general linear model that included the fixed effects of milking frequency, lactation number, interaction between milking frequency and lactation number, and as covariates proportion of F, heterosis F × J and deviation from the herd median calving date. Cows milked OAD produced milk with higher (p < .01) concentrations of protein and lactose than TAD milked cows. Compared to TAD cows, cows milked OAD had higher expression of the LF gene (1.40 vs. 1.29 folds, p = .03) and the IGF-1 gene (1.69 vs. 1.48 folds, p = .007). The correlation between the expression of LF gene and the concentration of LF in milk was strong (r = .66 p < .001), but the correlation between the expression of the IGF-1 gene and LF concentration was stronger (r = .94, p < .001). These results suggest that milking frequency affects the milk composition and expression of milk composition genes at early lactation.

Keywords: dairy cow; lactoferrin; milk; once a day; twice a day.

MeSH terms

  • Animals
  • Cattle / genetics*
  • Cattle / metabolism*
  • Female
  • Gene Expression*
  • Insulin-Like Growth Factor I / genetics
  • Insulin-Like Growth Factor I / metabolism
  • Lactation / genetics*
  • Lactation / metabolism*
  • Lactoferrin / genetics*
  • Lactoferrin / metabolism*
  • Milk / metabolism*

Substances

  • Insulin-Like Growth Factor I
  • Lactoferrin