Selecting for Subclinical Mastitis Resistance

Animals determined to have subclinical mastitis show no clinical signs or visible changes in the milk, but they do have a SCC greater than 200,000.
Animals determined to have subclinical mastitis show no clinical signs or visible changes in the milk, but they do have a SCC greater than 200,000.
(Farm Journal)

With milk prices not predicted to see much improvement until the second half of 2019, now is an important time to reduce your bulk tank somatic cell count (SCC) and examine methods to lower the occurrence of subclinical mastitis (SCM) on the farm.

Animals determined to have subclinical mastitis show no clinical signs or visible changes in the milk, but they do have a SCC greater than 200,000. Often times, mastitis in first-lactation heifers is rarely detected before calving, because clinical signs, such as a swollen quarter, can be hard to identify.

A recent study conducted by the University of Guelph, published in the December issue of the Journal of Dairy Science, examined the genetic parameters of SCM in first-lactation animals.


A BAD WAY TO START

Heifers who enter the milking herd with SCM will often have a lower lifetime productivity and profitability in the future, according to Canadian researchers. The prevalence of SCM in first-lactation heifers is usually highest during early lactation.

SCC test-day records were collected monthly on 91 Canadian herds. Taking samples on first-lactation animals during their first 5 to 30 days in milk, scientists compared a total of 8,518 records to six alternative traits that were defined as indicators of SCM.

GENETIC SELECTION

Using both linear and threshold genetic models, the study identified strong correlations among alternative SCC traits. Based on estimated breeding values (EBV) it was determined that genetic variation for SCM resistance existed among sires, making daughters less prone to the disease.

The study found that despite low heritability, genetic selection to improve genetic resistance to SCM in early lactation of heifers is possible. Working to select animals who are genetically less likely to obtain SCM may help reduce economic losses and premature culling of first-lactation heifers.

For more on this subject, read:

Tags

Dairy - General Milk - General Milk Quality Dairy Genetics Mastitis Dairy Cattle
 

Latest News

Business
Seven Common Threads of Top-Producing Herds
Seven Common Threads of Top-Producing Herds

What are the common characteristics of top-producing herds that best the competition?

Maureen Hanson
Policy
APHIS To Require Electronic Animal ID for Certain Cattle and Bison
APHIS To Require Electronic Animal ID for Certain Cattle and Bison

APHIS issued its final rule on animal ID that has been in place since 2013, switching from solely visual tags to tags that are both electronically and visually readable for certain classes of cattle moving interstate.

Greg Henderson
Education
What Should You Financially Consider Before Investing in Technology?
What Should You Financially Consider Before Investing in Technology?

With financial challenges facing dairy farms, Curtis Gerrits with Compeer Financial, says it is essential for producers to evaluate how these technology investments impact their farm’s overall financial position.

Karen Bohnert
Business
Fairlife Forms New Partnership with Olympic Gold Medalist Katie Ledecky
Fairlife Forms New Partnership with Olympic Gold Medalist Katie Ledecky

The Katie Ledecky partnership with fairlife's Core Power will leverage her authentic recovery moments to help educate and inspire athletes of all levels around the importance of post-workout recovery.

Taylor Leach
Education
Simple Breathing Exercises for Farmers to Help with Anxiety and Stress
Simple Breathing Exercises for Farmers to Help with Anxiety and Stress

More and more people in the dairy community are struggling because they are overworked or overstressed, have trouble concentrating, feel fatigued, have trouble sleeping, have more headaches and so many other symptoms. 

Karen Bohnert
Education
Properly Prepared Beef Remains Safe; Meat Institute Calls For Guidance to Protect Workers at Beef Facilities
Properly Prepared Beef Remains Safe; Meat Institute Calls For Guidance to Protect Workers at Beef Facilities

The Meat Institute said properly prepared beef remains safe to eat and called for USDA and the CDC to provide worker safety guidance specific to beef processors to ensure workers are protected from infection.

North American Meat Institute
View More