Prevalence, incidence and risk factors of heifer mastitis

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Abstract

Traditionally heifers, as calves and as primiparae, have been thought of as a group as free of mastitis. Without appreciable lacteal secretion, there is reduced nutrient fluid available to support growth of intramammary pathogens. Contagious mastitis is primarily transmitted at milking time and the milking process affects the patency of the teat orifice which can increase the risk of development of environmental mastitis. Logically therefore prepartum heifers should be free of intramammary infections. During the last 20 years there have been numerous investigations describing the nature of mastitis in heifers and thus the dogma that heifers are free of this disease has been challenged. The purpose of this manuscript is to review that literature describing heifer intramammary infections that cause both subclinical and clinical disease. Mammary quarter infection prevalence ranges between 28.9–74.6% prepartum, and 12.3–45.5% at parturition. Generally, the pathogens that cause mastitis in heifers are the same as those that cause infections in the older cows. In all but one study reviewed, coagulase-negative staphylococci (CNS) are the most prevalent cause of subclinical intramammary infections in heifers. Coagulase-positive staphylococci (CPS) in some studies are the second most prevalent pathogens, while in other studies the environmental mastitis pathogens are more prevalent. The risk factors for subclinical mastitis appear to be season, herd location, and trimester of pregnancy; all suggesting that management can have an impact in control of this disease prepartum. With respect to clinical mastitis, the most prevalent mastitis pathogen has been reported to be CNS in one study and CPS, or environmental mastitis pathogens, in other studies. The heifer is most at risk for clinical mastitis during the periparturient period. Risk factors found are related to diet, mammary gland factors such as edema and leaking of milk, and factors associated with the change in management and introduction of the heifer to the milking herd.

Introduction

It is common to introduce the subject of heifer mastitis by indicating that primiparae should in theory be free of intramammary infections (IMI) at first parturition. These animals have not experienced the rigors of multiple daily milkings, and thus have had less exposure to contagious pathogens that could be transmitted during milking time. Additionally, heifers have not been challenged with milking vacuums that have been associated with a deleterious effect on the structure of the teat end. For most of the heifer’s life, the mammary gland has been immature and it would seem less likely to be in close physical contact to the environment, as contrasted with multiparous cattle. However, mastitis in heifers is not uncommon, although tending to be less prevalent than mastitis in older cows. The focus of this manuscript is the description of pre- and postpartum prevalence and incidence of clinical and subclinical mastitis in heifers and a discussion of possible risk factors associated with heifer mastitis.

Section snippets

Subclinical mastitis in heifers

Mastitis is defined as inflammation of mammary gland and not as IMI. Yet IMI and mastitis are often used interchangeably. The measure of milk somatic cell count (SCC) is an often used measure of mammary inflammation and an increase in SCC is strongly correlated with increased probability of IMI (Eberhart et al., 1979, Dohoo and Leslie, 1991). The milk SCC threshold of 200,000 cells/ml is used to distinguish milk secretion from a mammary quarter with (>200,000 cells/ml) or without (<200,000 

Clinical mastitis in heifers

Classically, clinical mastitis in heifers was best known as the “summer mastitis syndrome” and the terms summer mastitis and heifer mastitis have been used synonymously (Seno and Azuma, 1983). In a review (Shearer and Harmon, 1993) of heifer mastitis, summer mastitis is described as an acute, suppurative infection affecting non-lactating animals, both dry cows and heifers. A. pyogenes and the anaerobe Peptococcus indolicus are frequently isolated (Shearer and Harmon, 1993). Additionally,

Conclusions

Studies of heifer mastitis were done as early as the 1930s (Munch-Petersen, 1970, Palmer et al., 1941). Yet it has been during the last 20 years when most studies have been made in an attempt to more fully describe the extent and nature of this problem world wide. The summer mastitis syndrome had been often considered to be perhaps synonymous with heifer mastitis. Yet even the early studies of the 1930s revealed that the common major mastitis pathogens that are most prevalent and cause mastitis

Conflict of interest

The author (L.K. Fox) does not have a financial or personal relationship with other people or organizations that could inappropriately influence or bias the paper entitled “Prevalence, incidence and risk factors of heifer mastitis”.

References (53)

  • S.P. Oliver et al.

    Intramammary infections in primigravid, heifers near parturition

    J. Dairy Sci.

    (1983)
  • S.P. Oliver et al.

    Influence of prepartum antibiotic therapy on intramammary infections in primigravid heifers during early lactation

    J. Dairy Sci.

    (1992)
  • S.P. Oliver et al.

    Prepartum antibiotic treatment of heifers: milk production, milk quality and economic benefit

    J. Dairy Sci.

    (2003)
  • S.P. Oliver et al.

    Influence of prepartum pirlimycin hydrochloride or penicillin-novobiocin therapy on mastitis in heifers during early lactation

    J. Dairy Sci.

    (2004)
  • J.W. Pankey et al.

    Mastitis prevalence in primigravid heifers at parturition

    J. Dairy Sci.

    (1991)
  • K.I. Parker et al.

    Subclinical and clinical mastitis in heifers following the use of a teat sealant precalving

    J. Dairy Sci.

    (2007)
  • J.R. Roberson et al.

    Coagulase-positive Staphylococcus intramammary infections in primiparous dairy cows

    J. Dairy Sci.

    (1994)
  • J.R. Roberson et al.

    Ecology of Staphylococcus aureus isolated from various sites on dairy farms

    J. Dairy Sci.

    (1994)
  • J.K. Shearer et al.

    Mastitis in heifers

    Vet. Clin. North Am. Food Anim. Pract.

    (1993)
  • C. Svensson et al.

    Effects of housing, management, and health of dairy heifers on first-lactation udder health in southwest Sweden

    J. Dairy Sci.

    (2006)
  • P. Trinidad et al.

    Prevalence of intramammary infection and teat canal colonization in unbred and primigravid dairy heifers

    J. Dairy Sci.

    (1990)
  • S. Waage et al.

    Bacteria associated with clinical mastitis in dairy heifers

    J. Dairy Sci.

    (1999)
  • A.C. Whist et al.

    Streptococcus dysgalactiae isolates at calving and lactation performance within the same lactation

    J. Dairy Sci.

    (2007)
  • J. Barnouin et al.

    Predictive variables for the occurrence of early clinical mastitis in primiparous Holstein cows under field conditions in France

    Can. Vet. J.

    (2001)
  • E. Berry et al.

    Summer mastitis in England and Wales: 1992–1997

    Vet. Rec.

    (1999)
  • A.J. Bramley et al.

    Corynebacterium pyogenes mastitis among heifer calves

    Vet. Rec.

    (1977)
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