HERD HEALTH
PIH-37
PURDUE UNIVERSITY • COOPERATIVE EXTENSION SERVICE • WEST LAFAYETTE, INDIANA
pork
industry
handbook
Lactation Failure in the Sow
Authors
William C. Wagner, University of Illinois
Ronnie G. Elmore, Texas A&M University
Richard F. Ross, Iowa State University
Bradford B. Smith, Oregon State University
Reviewers
Lowell Breeden, Kansas State University
Bruce Lawhom, Texas A&M University
David Meeker, Des Moines, Iowa
Donald Van Tine, Garfield, Washington
Lactation failure in swine (in the past commonly referred to as “MMA” or “mastitis, metritis, agalactia”) is a disease syndrome that results in the death of baby pigs through starvation or increased susceptibility to other diseases of the newborn. It is referred to as a syndrome to indicate that there may be several causative factors and clinical diseases that are referred to collectively as lactation failure. Because of the economic impact, lactation failure is of major importance to the pork producer.

The usual swine agalactia syndrome occurs in the very early stages of lactation. If the herdsman or attendant has been trained to recognize the signs, the disease may be evident to him at farrowing. Under the title of lactation failure, a sow can have a total lack of milk production (agalactia); but more frequently, the sow has only a reduction in normal amounts of milk secreted (hypogalactia). This hypogalactia or reduced milk production may be more difficult to recognize because piglets grow at a slower rate with only occasional deaths. The number of sows or gilts affected with this disease syndrome during a farrowing period in a given herd varies from 0% to 100% with an average of 13.1%.
Signs and Symptoms
Lactation failure can be present at farrowing time or can appear within several days after parturition. Although some hypogalactic sows are clinically normal, signs observed in affected females may include rapid breathing, depressed attitude, lack of desire to eat or drink, fever, reluctance to move about, and refusal to allow nursing. When the herdsman observes uncomfortable baby pigs, he should realize this indicates a need for closer evaluation of the sow.
Mastitis, an inflammation of the mammary glands usually caused by bacterial infections, is a frequent component in this disease syndrome. Although earlier reports have suggested that abnormalities or disease were present in other organs such as the uterus, ovaries, or adrenals, it is now agreed that the mammary glands of the sow or gilt are the primary location of the problem. The degree of agalactia varies from only one gland to the entire udder. The affected mammary glands are usually enlarged, more firm, warmer, more sensitive, and often discolored when compared to the other glands although hypogalactic sows may experience little or no change. Careful palpation of the mammary glands of each sow several times within the first 12 to 36 hours after farrowing may reveal developing hypogalactia and allow for treatment early in the syndrome. In some sows, the affected glands may show typical signs of regression similar to that seen at weaning. In these instances, the glands probably are not mastitic. Palpation prior to farrowing can be helpful in detecting sows with excessively hard or edematous (“caked”) glands. The presence of purulent discharge (pus) from the birth canal does not necessarily indicate that the sow or gilt has a uterine infection (metritis). Studies have revealed that over 60% of clinically normal sows have a vulvar discharge. Postmortem examinations of sows having agalactia indicate metritis is very infrequent in this disease condition.

Tissue changes within the affected sow are variable because of the different causative agents or management factors involved. Lactation failure can be a primary disease or secondary to other diseases. The majority of affected animals will reveal abnormal mammary gland tissues. The changes may be characteristic of mastitis, or a partially functional gland, without mastitic changes or be undergoing complete regression.
Cooperative Extension work in Agriculture and Home Economics, state of Indiana, Purdue University and U. S. Department of Agriculture cooperating. H. A. Wadsworth, Director, West Lafayette, IN. Issued in furtherance of the acts of May 8 and June 30, 1914. The Purdue University Cooperative Extension Service is an affirmative action/equal opportunity institution.