Erysipelas: Potential Involvement in Urogenital Disease of the Sow

Peer reviewed Case Report Erysipelas: Potential involvement in urogenital disease of the sow

Winfried Gertenbach, PhD; Gabor Bilkei, DVM, PhD tiveness of SE vaccination is its inability to dence of periparturient vulval discharge Summary prevent the chronic form of SE. Most in- decreased, the farrowing interval dimin- Although systemic infections with Ery- vestigators agree that vaccination has little ished, and live-born litter size increased. In sipelothrix rhusiopathiae in swine are usually effect on the incidence of chronic SE, al- the absence of a control group, definitive associated with skin lesions, vegetative en- though this observation is difficult to conclusions cannot be made regarding the docarditis, and arthritis, infections may evaluate in the field. It is possible that vac- effect of vaccination against E rhusiopathiae cause abortion or influence stillbirth rate cination reduces the overall prevalence of on sow fertility. However, it is not unrea- and litter size. In a large production unit any chronic manifestation of SE. On the sonable to suggest that E rhusiopathiae was that had ceased to vaccinate against erysip- other hand, some believe that vaccination involved in the etiology of the reduced sow elas, an increased incidence of pre- and actually causes an increase in chronic SE fertility in this herd and that appropriate postparturient vulval discharge, longer far- lesions by initiating a state of hypersensitiv- vaccination subsequently protected the rowing intervals, and a reduction in live- ity to subsequent contact with the organ- sows. born litter size were reported. Anterior ism.1 In our practice, we suspect chronic vaginal swabs obtained from 21 sows Keywords: swine, sow, erysipelas, fertility SE in herds where vegetative endocarditis, shortly before parturition all yielded heavy arthritis, and cultural presence of E Received: March 6, 2001 growth of E rhusiopathiae. When a vaccina- rhusiopathiae in vulval discharge are accom- Accepted: December 11, 2001 tion program was re-instituted, the inci- panied by poor fertility and increased prevalence of abortions, stillbirths, and small litter size.3,4 This report describes the wine erysipelas (SE), caused by infec- ease, may progress to chronic SE,1 which is effect of vaccination against E rhusiopathiae tion with Erysipelothrix rhusiopathiae, characterized by proliferative lesions such on subsequent fertility in a sow herd in Soccurs in most parts of the world as arthritis or vegetative endocarditis.3 A which there had been a marked increase in and in most areas where domestic swine are form of the chronic disease that is not well occurrence of purulent periparturient vul- produced.1 The primary source of infection understood is a possible effect on the re- val discharge. There have been no previous for swine is other swine.1 The organism is productive performance of the sow herd.4 published reports concerning development believed to be transmitted directly via In addition to abortion, SE may cause fetal of SE in the urogenital system of the sow. oronasal and fecal secretions or indirectly mummification and other reproductive via environmental contamination.2 Pigs problems in the sow herd.3 Case description may be infected by ingestion of contami- The affected large commercial unit had Naturally acquired active immunity is in- nated feed or water or contamination of 1500 breeding sows with a history of SE. duced by previous infection with E skin wounds.2 In indoor production sys- During the previous 12 months, the preva- rhusiopathiae. Less clearly recognized is the tems, contamination of concrete floors lence of purulent vulval discharge in immunity that may be induced by organ- with the feces and urine of infected pigs is prepartum sows had increased from 8 to isms of low virulence, which are capable of the likely source of infection.1 Acute SE is 21%, occurring during the 1 to 2 days causing subclinical infections or mild, un- characterized clinically by sudden death prior to parturition. In the same period, noticed subacute disease. and pyrexia associated with diamond- the prevalence of purulent vulval discharge shaped skin lesions.1 In pregnant sows, Preventive methods include optimizing in postparturient sows rose from 15 to acute or subacute SE has also been associ- biosecurity and sanitation in order to pre- 34%, with a duration of >5 days postpar- 4 ated with abortion.1,3 vent direct infections. Attenuated vaccines tum and a total volume of >100 mL in and bacterins against E rhusiopathiae are older sows. Record analysis showed that 1 According to Wood, the clinical signs of commercially available.2 Vaccination fail- during that 12-month interval, compared SE may be classified as acute, subacute, or ures rarely occur but have been reported to earlier years of production, the farrow- chronic. In addition, subclinical infections, when the field strain was not contained in ing rate had decreased from 81 to 74%, which cause no visible signs of acute dis- the bacterin.4 A serious flaw in the effec- and litter size had decreased from a mean of 11.0 (SE 0.91) to 10.2 (SE 0.76) live WG, GB: Bilkei Consulting, Raubbühlstr 4, CH - 8600 Dübendorf, Switzerland. pigs per litter. This article is available online at http://www.aasv.org/shap.html. Anterior vaginal swabs obtained from 21 Gertenbach W, Bilkei G. Erysipelas: Potential involvement in urogenital disease of the sow. J Swine sows exhibiting prepartum vulval discharge Health Prod. 2002;10(5):205-207. were submitted for bacteriological culture. Journal of Swine Health and Production — Volume 10, Number 5 205 The results of these cultures revealed heavy Discussion Farrowing is accompanied by contamina- growth of E rhusiopathiae and occasional Infectious agents not commonly thought tion of the cranial vagina in nearly all sows Escherichia coli. Herd health records to be reproductive pathogens may cause and contamination of the cervix and uterus showed that vaccination against E rhusio- failure of pregnancy either through their in the majority of sows.6 While most bacte- pathiae had been discontinued 20 months general systemic effects on the sow or by ria are eliminated within 12 to 30 hours previously. infecting the fetus.4 The possible effect of after delivery, facultative pathogens may overgrow nonpathogenic microflora and An erysipelas vaccination program was re- E rhusiopathiae in this case may have been establish mildly invasive endometritis.6 instituted, with sows receiving a killed vac- caused by an ascending urogenital infection Numerous agents have been isolated from cine (Rhusilisat; Veterinaria, Zürich, Swit- or by allergic response to chronic erysipelas vulval discharges (and from uteri) of sows, zerland) at 40 and 55 days of gestation. It infection. It has been suggested that E but it is still unclear which are pathogens was necessary to administer the two doses rhusiopathiae causes reproductive problems and which are opportunistic invaders. Ery- of erysipelas vaccine in a 2-week interval in the sow and may enter the uterus of the sipelothrix rhusiopathiae may be an oppor- because of other vaccines (for E coli, Lep- sow at mating or at parturition when the 4 tunistic invader of the urogenital tract of tospira serovars, and pseudorabies virus) cervix is open. the sow, and may be able to overgrow other given during gestation. Vulval discharges are often associated with opportunistic organisms in the urogenital Twelve months after the re-institution of chronic endometritis or with swine uro- tract of the periparturient sow. It is also 5 erysipelas vaccination, the monthly preva- genital disease. Some discharges are nor- possible that soon after parturition, the lence of both prepartum vulval discharge mal physiological events, while others – urogenital organs are simultaneously colo- (mean 11.4%, SE 2.1%) and postpart- especially purulent discharges – are patho- nized by multiple organisms from the cra- urient vulval discharge (mean 16.3%, SE logical and are particularly important, as nial vagina, which may include indigenous 6 2.9%) had decreased compared to the 20- herd fertility may be significantly affected. microbes, bacterial contaminants, and month period when the sows were unvacci- Postparturient discharges represent clear- pathogens (in this case, E rhusiopathiae). nated (P<.05). Four months after vaccina- ance of placental remnants and debris from Perhaps immunological naivete of the en- 5 tion, anterior vaginal swabs obtained the uterus. The volume of vulval discharge dometrium, especially in young parity fe- prepartum from 17 of the 21 sows previ- varies considerably, as does its texture, males or in non-vaccinated sows, facilitates ously cultured revealed no growth of E ranging from an opaque, mucoid material colonization by E rhusiopathiae. 7 rhusiopathiae. flecked with debris to purulent exudate. Recovery from postpartal uterine infections In acute SE, areas of congestion may be To obtain a more objective measure of the is influenced by many factors, including found in the urinary bladder mucosa.3 efficacy of erysipelas vaccination, farrowing hormonal status of the sow, local immu- Chronic urogenital infections caused by E interval and litter size were examined for nity, and the possible influence of reduced rhusiopathiae often result in proliferative sows that farrowed in the pre-vaccination leukocyte activity and delayed immune bladder mucosal changes, ie, coagulopathy (n=3511) and post-vaccination periods response of the postpartum uterus.4 In- and fibrinous exudates.4 Mucosal hyper- (n=3702). Average parity of bred sows was creased postpartum uterine immunglobulin emia and congestion, mucosal ulceration, 2.9 during the pre-vaccination period and concentrations aid in clearing uterine infec- and accumulation of fibrinopurulent exu- 2.8 after vaccination had been reinstituted. tions.4 Approximately 80% of IgG and date over affected areas of the urinary blad- Data were analyzed by analysis of variance 60% of IgA in the uterus of the sow are der mucosa has been reported in chronic (Statistix; Analytical Software Inc, Tallahas- serum derived,8 underlining the impor- SE.5 Similar changes may occur in the early see, Florida). The differences in production tance of vaccination status of the sow postpartum endometrium as well. Because data between the 12-month pre-vaccina- against E rhusiopathiae infection. There is a tissue decomposition provides a medium tion period and the 12-month post-vacci- tendency for IgA levels to be higher in the conducive to the growth of a variety of op- nation period were evaluated by Student cervix and vagina than in the oviduct or portunistic microorganisms, retention of two-phase t-test assuming unequal vari- uterus.8 However, in response to elevated remnants of the placenta may predispose ances. All management variables were prefarrowing serum estradiol concentra- sows to mild metritis and endometritis.4 In evaluated with dependant variables (pre- tions (that rapidly decrease after parturi- this case, we suspect that the sows devel- vaccination, post-vaccination). tion), there are profound increases in the oped mild chronic postparturient en- dometritis caused by E rhusiopathiae, and The farrowing interval (mean ± SE) de- total numbers of circulating leucocytes that this infection continued throughout creased from 159.1 ± 6.1 days in the pre- (both lymphocytes and neutrophils), the lactation. It is possible that in the infected vaccination period to 146.1 ± 4.2 days in percentage of immunglobulin-bearing sows, the cervix closed normally within a the post-vaccination period (P=.04). Live- mononuclear cells, and the phagocitic ca- 9 few days of farrowing, preventing drainage born litter size increased from 10.2 ± 0.76 pacity of polymorphonuclear leucocytes. of the uterine content. In the absence of pre-vaccination to 11.7 ± 0.77 post-vacci- These alterations may increase the sow’s cyclic changes in ovarian activity during nation (P=.03). There was no difference response to infectious agents. lactation, there is inadequate endocrine (P≥.05) in numbers of stillborn pigs (pre- The reproductive and urinary tract are pre- modulation of mucosal immune responses. vaccination, 1.3 ± 0.03; post-vaccination, disposed to infection after farrowing be- Consequently, the ability of affected sows 1.2 ± 0.03) or 21-day litter weights (pre- cause of the periparturient increase in the to resolve the infection was further vaccination, 61.1 kg ± 2.1 kg; post-vacci- numbers of both nonpathogenic and facul- compromised. nation, 62.0 kg ± 1.9 kg). tative pathogens in the caudal vagina.5 206 Journal of Swine Health and Production —September and October, 2002 Other large herds owned by the same 5. Bilkei G, Bölcskei A, Goos T. Pathogene Befunde Implications aus dem Urogenitaltrakt ausgemerzter Muttersauen breeding organization in the same geo- •In herds experiencing an increase in aus einem Grossbestand. (Pathological findings in graphic area shared some managers and periparturient vulval discharges, a urogenital organs of culled sows in a large breeding technicians, who moved frequently be- culture of the discharge material is unit). Tierärztliche Praxis. 1995;23:37–41. tween the herds. Within a 30-km radius of indicated to rule out less obvious 6. Berner H. Die Bedeutung von Harnwegsin- fektionen für die Entstehung der puerperalen en- the investigated production units, the fol- causes, such as E rhusiopathiae. dometritis beim Schwein (The importance of uri- lowing infectious agents were identified in •Because of the ubiquity of E nary tract infections in the development of puer- vulval discharges of sows: Clostridium spp, rhusiopathiae and its poorly under- peral endometritis in swine). Tierärztiche Umschau. 1984;39:450–458. Actinobaculum suis (formerly Eubacterium stood ability to exist in nature, the 7. Dial GD, MacLachlan NJ. Urogenital infections suis), Klebsiella spp, Proteus spp, and E coli. possibility of eradication of the of swine. Part 1. Clinical manifestations and patho- However, E rhusiopathiae was identified organism seems remote; therefore, genesis. Comp Cont Ed Pract Vet. 1988;10:63–71. only in the case herd. In our opinion, there vaccination should be used in 8. Hussein AM, Newby TJ, Bourne FJ. Immunohis- is strong circumstantial evidence that E conjunction with good management tochemical studies of the local immune system in the reproductive tract of the sow. J Reprod Immunol. rhusiopathiae played a role in the fertility practices to control swine erysipelas. 1983;5:1–16. problems observed in this herd. 9. Magnusson U, Einarson S. Effects of exogenous References – refereed oestradiol on the number and functional capacity of Under field conditions, in large breeding circulating mononuclear and polymorhonuclear units, erysipelas vaccination is not always 1. Wood RL. Erysipelas. In: Straw BE, D‘Allaire S, Mengeling WL, Taylor DJ. Diseases of Swine. 8th ed. leucocytes in the sow. Vet Immunol Immunopathol. entirely effective in preventing disease. De- Ames, Iowa: Iowa University Press. 1999;419–430. 1990;25:235–247. spite vaccination, some sows may still be 2. Amass SF, Scholz DA. Acute nonfatal erysipelas affected by the disease, but vaccination in sows in a commercial farrow-to-finish operation. provides a worthwhile means of control for JAVMA. 1998;212:708–709. the whole herd. In this case, we noted a 3. Plonait H, Bickhardt K. Lehrbuch der Schweinekrankheiten (Study of swine diseases). Ber- marked reduction in periparturient vulval lin: Parey. 1997;105–110. discharge after erysipelas vaccination. Four 4. Bilkei G. Sauenmanagement. (Management of the months after vaccination, E rhusiopathiae breeding sow). Jena and Stuttgart: Fischer. 1996;3– was not cultured from anterior vaginal 57. swabs of 17 of the 21 sows that had been culture-positive prepartum. We have no explanation for this phenomenon other than that vaccination against SE was pro- tective in these sows.

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