TITLE:
An Interconnection between Elevated SCC Levels in Milk around the First Artificial Insemination and Pregnancy Rate in Dairy Cows
AUTHORS:
Găvan Constantin
KEYWORDS:
Somatic Cell Count, Fertility, Pregnant Rate, Test-Day-Milk Data
JOURNAL NAME:
Open Journal of Animal Sciences,
Vol.13 No.4,
October
26,
2023
ABSTRACT: The aim of this study was to evaluate the impact of the somatic cell
count (SCC) levels measured at 28-test-day intervals or pregnancy rate at the first artificial insemination of Holstein Friesian cows. All necessary
information was taken from test day and farm records. Levels of SCC in milk, 30 days
before, and 30 days after the first artificial insemination (FAI) date were divided into 4
categories and their interconnection with pregnancy rate (PR) at FAI was
evaluated by applying logistic models. A SCC threshold of 150.000 cells/ml of milk was
used to differentiate uninfected udders and infected udders of Holstein
Friesian cows. A level of SCC > 150.000 cells/ml in milk, and a level of SCC
150.000 cells/ml in milk before FAI as
well as after FAI, was considered chronically infected udders or subclinical
intramammary infections (IMI). Data from 792 FAIs from farm and test day
records over a 4-year period (2019-2022) were evaluated. The outcome of this study
revealed that the risk for low PR at the first AI was increased in cows with infected udders (OR = 1.33, CI 0.99 - 1.78),
compared with uninfected udders. Increased levels of SCC after FAI had a negative
effect on PR, while before FAI was not affected. To achieve a good PR, mastitis control
measures must be fully adopted to a large extent around the first AI.