Prevalence of Staphylococcus Species During the Periparturient Period in Primiparous and Multiparous Cows1

Prevalence of Staphy/ococcus Species During the Periparturient Period in Primiparous and Multiparous Cows' K. R. MAITHEW$ Department of Animal Science University of Tennessee Knoxville 37901

R. J. HARMON and B. E. LANGLOIS Department of Animal Science University of Kentucky Lexington 40546-0215

than in multiparous cows. These data

ABSTRACT

During a 14-mo period, 77 multiparous and 36 primiparous cows were sampled to determine the prevalence of staphylococci during the periparturient period. Distal streak canal swabs were taken at 14 d prepartum, and foremilk was sampled the first 5 consecutive wk of lactation. Staphylococcus aureus was isolated from 7.6% of quarters of primiparous cows but from only .6% of quarters of multiparous cows at parturition. Prevalence in primiparous cows declined to 3.5% by the wk-1 sampling. Quarter prevalence of coagulase-negative Staphylococcus species prepartum, at parturition, and wk 1 to 5 in primiparous cows was 38.9, 27.8, 15.3, 14.6, 13.2, 15.3, and 14.6%, respectively. In multiparous cows, prevalence at these times was 50.3, 12.3, 6.2, 8.1, 10.7, 7.1, and 8.1%. Sraphylococcus chromogenes was the predominant species isolated, accounting for over 50% of the staphylococci isolated at each sampling time. Results suggest that high prevalence of staphylococci isolated prepartum is a reflection of natural skin flora and that a higher postpartum prevalence of these organisms was observed in primiparous cows

suggest also that the peripartum heifer could be a source of Staphylococcus aureus in the lactating herd. (Key words: staphylococci, mammary gland, bovine) Abbreviation key: CNS = coagulase-negative staphylococci. IMRODUCTION

The importance of udder health in the primiparous cow upon entering the milking herd cannot be overstated. Because these cows are herd replacements and will have an impact on future production and milk quality, it is imperative that primiparous cows begin the lactation with a low prevalence of IMI at parturition. Staphylococcus aureus, a contagious pathogen, still remains a common mammary pathogen. Although the major reservoir is the infected udder of lactating cows, S. aureus can persist for long periods in other body sites, including the nares, teat and skin lesions, the vagina, and infected tonsils of cows (8, 11, 18). Most of the remaining Staphylococcus species are coagulase-negative and are considered to be minor pathogens (5). Coagulase-negative staphylococci (CNS) are often the most prevalent organisms isolated from milk samples in herds using currently recommended control measures (5). Recent reports indicate that CNS can be isolated with Received January 27, 1992. Accepted February 25, 1992. high frequency from body sites, streak canals, h i s manuscript (92-5-8) is published with (he ap- and mammary secretions of nulliparous heifers proval of the director of the Kentucky Agricultural Experi(1, 18, 20). Sraphylococcus aureus IMI in nulment Station. liparous heifers have also been reported (1, 8, %o whom correspondence should be addressed. 1992 J Dairy Sci 751835-1839

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14), suggesting that sources other than the lactating cow may serve as reservoirs of S. aureus in the dairy herd. Staphylococcal IMI during the prepartum period may be deleterious to future milk production, particularly production by primiparous cows (1). Harmon and Langlois (5) indicated that SCC in C N S infected quarters may be two- to threefold higher than SCC in bacteriologically negative quarters. Timms and Schultz (17) suggested that C N S IMI can cause a decline in milk production, in contrast to the findings of Eberhart et al. (3), which suggest no decline in milk production. StaphyZococcus aureus IMI are more likely to persist into the new lactation compared with infections by other mastitis pathogens (14). Despite the availability of a variety of antibiotics and numerous reports on the sensitivity of S. aureus to antibiotics, treatment success during lactation is still very low. Therefore, persistence of S. aureus infections into lactation could be of great economic importance. The purpose of the study was to compare the prevalence of IMI caused by Staphylococcus species in primiparous and multiparous cows in the periparturient period.

presence of staphylococci. Before swabbing, teats and the lower one-third of the udder were washed and dried thoroughly with single-use paper towels. Teat ends were then scrubbed with cotton swabs soaked in 70% isopropyl alcohol. Teat orifice swabs were obtained by gently inserting a cotton-tipped swab into the distal end of the streak canal and rotating. After sampling, the swab head was carefully broken off into 4.5 ml of phosphate-buffered diluent (9), and the vial was placed on ice for transport to the laboratory. Duplicate foremilk samples were aseptically collected from cows at drying off, parturition, and weekly for 4 consecutive wk postpartum for bacteriologic analysis. Prior to sampling, the udder of each cow was washed and dried thoroughly, quarters were checked for abnormal secretion, and teat ends were scrubbed with cotton swabs soaked in 70% isopropyl alcohol. Bacterla

All samples were plated on blood-esculin agar for primary isolation. Plates were incubated for 48 h at 35'C. Staphylococci were identified by Gram reaction, catalase, coagulase tests, and sensitivity to lysostaphin, bacitracin, and novobiocin (7, 10). Staphylococci MATERIALS AND METHODS were identified to species level by the MI* Seventy-seven multiparous and 36 primipa- Staph-trac system (Analytab Products, Plainrous cows in the University of Kentucky dairy view, NY) (10). A sample was considered herd were sampled during a 14-mo period. positive when the same organism was isolated Animals were housed in a three-sided free-stall from duplicate quarter samples. barn bedded with hardwood sawdust during lactation. Heifers were housed in a three-sided RESULTS AND DISCUSSION barn with access to pasture prior to entering the herd. Cows were on pasture during the dry Quarter infection prevalence by Sraphyloperiod with access to shelter. For collection of coccus species is shown in Tables 1 and 2. teat orifice swabs, all cows were relocated to a Staphylococci were isolated from approxithree-sided open pen bam, bedded with saw- mately 50% of quarters in primiparous and dust 14 d prior to expected calving date. Ap- multiparous cows. Prevalence of S. aureus proximately 7 d prior to calving, all cows were (6.9%) prepartum in primiparous cows was moved to box stalls bedded with straw. Lactat- three times greater than in multiparous cows ing cows were teat dipped posuniUcing with a 1% iodophor teat dip, and all quarters of all (2.3%). Differences in quarter prevalence of S. aureus in primiparous cows (7.6%) compared cows received dry cow therapy at last milking with a commercial preparation containing with that in multiparous cows (.6%) was most evident at parturition. Staphylococcus aureus cephapirin. prevalence in infected quarters declined by at least 50% in both groups by early lactation. Sampllng Procedures Schultze (14) reported an unexpectedly high Teat orifice swabs were taken from all cows (13.1%)proportion of S. aureus infections in approximately 14 d prepartum to determine the primiparous cows compared with multiparous Journal of Dairy Science Vol. 75, No. 7, 1992

PREVALENCE OF

sTApHwcoccus SPECIES

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TABLE 1. Quarter prevalence of Staphylococcus species in primiparous cows in the peripartorient period and bough wk 5 of lactation" Week3

Snecies

PreDartumz

parcuritiOn3

1

aureus hominis chromogenes warnm' s. xylosus S . epidennidis S. simulans Staphylococcus spp. Total

6.9 2.8 28.5 .7 .7 2.1 3.5 .7 45.9

7.6 .7 18.8

3.5 .7 12.5 .7 .7

2

3

5

4

(46) S. S. S. S.

... .7 2.8 4.2 .7 35.5

3.5 1.4 10.4

5.6 .7 9.0

...

...

2.1 .7

.7 2.1 .7 18.8

...

... .7 ...

...

18.8

18.1

...

2.8 1.4 9.7

... 1.4 .7 2.1

3.5 1.4 9.7 .7

...

...

... 2.8 ...

18.1

18.1

'From 36 cows, 144 quarters. 2F'repartum prevalence data fiom teat orifice swabs. 3Data from duplicate foremilk samples.

cows (2.9%) during the periparturient period. New IMI by CNS in primiparous and multiparous cows during the same period were similar to those in the present study. hesence of S. aureus in heifers may be expected. Trinidad et al. (18) studied prevalence of mastitis in 116 breeding age and pregnant heifers in four herds. Of 370 quarter secretion samples collected, 14.9% were positive for S. aweus in 37.1%of heifers. However, Oliver and Mitchell (13) observed a quarter prevalence of S. aureus in the peripartum period of 1% or less. Prevalence of S. aureus isolated from teat

canals in the present study was similar to values reported previously (1, 9). Prevalence of C N S in primiparous cows remained nearly twice as high postpartum as CNS in multiparous cows. Staphylococcus chromogenes was the predominant CNS, accounting for approximately 70% of CNS isolates. Staphylococcus hominis, Staphylococcus epidennidis, and Staphylococcus simuians were isolated less frequently. Prevalence of quarter infection by Staphylococcus warneri and Staphylococcus xyiosus was greater in multiparous cows than in primiparous cows

TABLE 2. Quarter prevalence of Sraphyfococcusspecies in multiparous cows in the periparturient period and through wk 5 of laCtatiOn.1

Week3 Suecies

PreDartum2

parcuritions

S. S. S. S.

2.3 7.1 28.9 3.9

.6 .6 10.4

aureus hominis chromogenes warneri s.xylosus S . epidennidis S. simulans Staphylococcus spp. Total

2.6 3.2 1.o 3.6 52.6

... ... 1.o ... .3 13.0

1

2

.6 .3 4.2 .7

... 1.o

.6

... 7.4

3

1.0 .3 6.2

... .3 .6 -3 .3 9.0

4

1.0 1.3 8.1

5 .3

.6 6.2

.3 1.o 6.2 .7

... ...

... ...

...

.3

.3 2.1

.6 2.8

... 1.0 11.7

...

...

9.5

11.6

'From 77 cows, 308 quarters. 2Prepartum prevalence data from teat orifice swabs. 3Data from duplicate foremilk samples.

Journal of Dairy Science Vol. 75, No. 7, 1992

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MATIHEWS ET AL.

prepartum. Staphylococcus warneri and S. xylosus declined markedly by parturition in multiparous cows and were isolated infrequently in both groups by early lactation. White et al. (20) reported that S. xylosus, S. chromogenes, and S. warneri were the predominant species isolated from anatomic sites of heifers. In this study, S. chromogenes was the predominant species found in the streak canal, which is in agreement with observations concerning IMI in lactating cows (5). Boddie et al. (1) and Trinidad et al. (18) found that S. chromogenes and Staphylococcus hyicus were the predominant CNS isolated from teat canal keratin and mammary secretion samples of breeding age and pregnant heifers. Recently, it was reported that S. xylosus and Staphylococcus sciuri were isolated from fresh and used bedding materials and that these organisms are free-living in the environment (8, 20). The isolation of S. xylosus on teat skin and other external surfaces of cows may be the result of environmental contamination. The CNS data (Tables 1 and 2) are consistent with previous observations in this herd (5) and with those of Oliver and Mitchell (12). Coagulase-negative staphylococci are often the most prevalent organisms isolated from mammary secretions of lactating cows (2, 5, 19) and dry cows (13, 14). Harmon and Langlois ( 5 ) indicated that prevalence of CNS IMI ranged from 6 to 16% of quarters and from 17 to 40% of cows. Although CNS are generally associated with subclinical cases of mastitis, clinical mastitis episodes can occur (15, 16). During a 5-yr study, Smith et al. (15) reported that CNS were cultured from 9.0% of milk samples collected from quarters with clinical mastitis. Coagulase-negative staphylococcal IMI present during late lactation can be controlled by routine intramammary antibiotic treatment of all quarters of all cows at drying off. However, Harmon et al. (4) reported that 72.7% of untreated control mammary glands infected at drying off were not infected postpartum, indicating that a high rate of spontaneous elimination occurred during the dry period. Distribution and percentage of quarters infected with staphylococcal species may vary among herds (19). Many factors may influence differences, including crosscontamination between cows and heifers, source and type of bedding, condition of pastures and exercise Jonrnal of Dairy Science Vol. 75, No. 7, 1992

areas, and type of germicide in use. Harmon et al. (6) conducted a long-term study to compare the influence of 1.94% linear dodecyl benzene sulfonic acid teat dip with that of 1% iodophor

on Staphylococcus species prevalence. Results indicate that, after 20 mo, the quarter prevalence of S. aureus and CNS IMI were significantly greater in the linear dodecyl benzene sulfonic acid group than in the iodophor group. Staphylococcus aureus new IMI rate and number of new IMI were fivefold higher in the linear dodecyl benzene sulfonic acid group than in the iodophor group (6). Results of Harmon et al. (6) are in agreement with those of others (19) suggesting that the germicidal agent used for postmilking teat antisepsis may affect distribution of staphylococcal species in herds. CONCLUSIONS

Previous reports (1, 8, 18, 20) suggest that

CNS are part of the normal flora of the bovine and can be isolated with high frequency. Therefore, new CNS IMI during the prepartum period, when recommended control measures are not effective, are likely to occur. Results of this study and others (1, 14, 18) suggest that prepstaphylococcal IMI in primiparous and multiparous cows can persist into early lactation. These data suggest also that periparturn heifers could be a source of S. aureus in the lactating herd. New IMI by S. aureus at calving in primiparous cows would seem less likely when the primary reservoir is the infected mammary gland and when transmission occurs during milking. ACKNOWLEDGMENTS

Technical assistance of K. Akers and B. Smith is greatly appreciated. Authors express their appreciation to Arlene Stewart for excellent clerical assistance. Thanks are extended to J. J. Rejman for critical review of this manuscript. REFERENCES 1 Boddie, R L.,S. C. Nickerson, W.E.Owens, and J. L.Watts. 1987. Udder microflora in nonlactatingheifITS. Agri-RaCtice 8~22. 2 Devries, L.A., and H.Dekeyser. 1980. Prevalence of

PREVALENCE OF STAPHYWCOCCUS SPECIES

Werent species of coagulasanegative staphylococci on teats and in milk samples from dairy cows. J. Dairy Res. 42155. 3 Eberhart, R. J., L. J. Hutchinson, and S. B. Spencer. 1982. Relatiomhips of bulk tank somatic cell counts to prevalence Of intnuaammary infstion~and to indices of herd production. J. Food Prot. 45:1125. 4 Harmon, R. J., W. L. Crist, R. W. Hemken, and B. E. Laoglois. 1986. Prevalence of minor udder pathogens after inbramammary dry treatment. J. Dairy Sci. 69: 843. 5 Harmon, R. J.. a d B. E.Langlois. 1989. Mastitis due to coagulassnegative Staphylococcus species. AgriPractice 10:29. 6 Harmon, R J.. B. E. Langlois, K. Akers. B. A. Smith, W. L. cri~t,and R W. Hemken. 1990. Long-term influence of two germicidal teat dips on Staphylococcus species pmalence and new infection rate of Staphylococcus aureus in a dairy herd. Page 103 in Roc. Int. Mastitis Symp., Natl. Mastitis Counc., Am. Assoc. Bovine Pract., Indianapolis, IN. 7Langlois, B. E., R J. Harmon, and K. Akers. 1988. Use of lysostapbiu and Bacitracin susceptibility for routine presumptive idenlification of staphylococd of bovine origin. J. Food Rot. 51% 8 Matos. J. S., D. G. White, R. J. Harmon, aod B. E. Langlois. 1991. Isolation of Staphylococnrs aureus from sites other than the lactating mammary gland. J. Dairy Sci. 741544. 9Matthews,K.R.,R. J.Harmon,B.E.Langlois, W.L. Crist, and R.W. Hemken. 1988. Use of latex teat dip with germicide during the prepartum period. J. Dairy Sci. 71:1940. IOMatthem, K.R, S. P.Oliver, and S. H. f i g . 1990. Comparison of Vitek Gram-positive identification system with API StapbTrac system for species identification of staphylococci of bovine origin. J. Clin.

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Microbial. 28:1649. 11Newbould, FILS. 1975. The possibilities of eradicating specific infections in mastitis control. Page 382 in Int. Dairy ped. Proc., Semin. Mastitis Control,Reading, -1. 12 Oliver, S. P., and B. A. Mitchell. 1983. Susceptibility of bovine znammary gland to infectionsduring the dry period. J. Dairy Sci. 66:1162. 13 Oliver, S. P., and B. A. Mitchell. 1983. Intramammary infections in primipavid heifers near parturition. J. Dairy Sd. 66:1180. 14 Schulm. W. D. 1985. Control of new -ni infections at calving by prepartum teat dipping. J. Dairy Sci. 682094. 15 Smith,K. L., D. A. Todhunter, and P. S. Schoenberger. 1985. Environmental mastitis: cause, prevalence, prevention. J. Dairy Sci. 681531. lasmith, T. W., R J. Eberhwt, S. B. Spencer, E. M Kesler, G. L. Hargrove, R W. Wilson, and C. W. Heald. 1985. Effect of automatic backtlushing on number of new intmmammq infections,bacteria on teatcup liners, and milk iodine. J. Dairy Sci. 68:424. 17TimmS. L. L., and L. H. Schultz. 1987. Dynamics and signifkame of coagulase-negative staphylococcal intramammary infections. J. Dairy Sci. 702648. 18 Trinidad, P.. S. C. Nickerson, and T. K.Alley. 1990. Prevalence of intramammary infection and teat canal colonization in unbred and primigravid dairy heifers. J. Dairy Sci. 73107. 19Watts. J. L., and W. E. Owens. 1989. Prevalence of staphylococcal species in four dairy herds. Res. Vet. Sci. M1. 20White, D. G., R. J. Harmon, J.E.S. Matos, and B. E. Laglois. 1989. Jsolation and identification of CoagUlasGnegative Staphylococcus species from bovine body sites imd streak canals of nulliparous heiiers. J. Dairy Sci. 72:1886.

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