LRH: R. Monleon and H. J. Barnes

RRH: Orchitis in broiler breeders

Case Report --

Bacterial Orchitis and Epididymo-orchitis in Broiler Breeders

R. Monleon and H. J. BarnesA

Poultry Health Management, Department of Population Health & Pathobiology, College

of Veterinary Medicine, North Carolina State University,

4700 Hillsborough St., Raleigh, NC 27606, U.S.A.

For submission to: Avian Diseases

ACorresponding Author. Dr. H. John Barnes, Poultry Health Management, Department

of Population Health & Pathobiology, College of Veterinary Medicine, North Carolina

State University, 4700 Hillsborough Street, Raleigh, NC 27606.

Tel: (919) 513-6273. Fax: (919) 513-6383. Email: john_barnes@ncsu.edu

2

SUMMARY. A unilateral case of orchitis due to Staphylococcus aureus and a bilateral

case of epididymo-orchitis due Escherichia coli are described. Male broiler breeders from

two different farms were collected and a unilateral orchitis and a bilateral epididymo-

orchitis were identified at necropsy. Bacteriology samples recovered S. aureus and E. coli

respectively. Microscopically, heterophilic interstitial-intratubular orchitis with

intralesional bacterial colonies was observed in both cases. Bacterial heterophilic

interstitial-intratubular epididymitis was observed in Case 2. Infection most likely

occurred via the ascending route.

RESUMEN. Un caso de orquitis unilateral por Staphylococcus aureus, y una epididimo-

orquitis bilateral por Escherichia coli son descritos. Machos progenitores de dos granjas

distintas fueron tomados y necropsiados, una orquitis unilateral y una epididimo-orquitis

bilateral fueron identificadas. En las muestras bacteriologicas S. aureus e E. coli fueron

identificados respectivamente. Microscopicamente, orquitis intersticial-intratubular

heterophilica con colonias bacterianas en la lesion fueron observadas en ambos casos.

Epididimitis intersticial-intratubular heterophilica bacterianas fue observada en el Caso 2.

La via ascendente fue considerada la ruta mas probable de infeccion.

3

Keywords: orchitis, epididymo-orchitis, Staphylococcus aureus, Escherichia coli,

infertility

Abbreviations: O/E/EpO = Orchitis / Epididymitis / Epididymo-orchitis

4

Broiler breeder infertility is a major concern in the poultry industry that can result

in severe economic significance. Orchitis, epididymitis and epididymo-orchitis

(O/E/EpO) cause fertility performance impairment in male breeders, thus decreasing their

productivity. In poultry, these infections have previously been associated with

Salmonella spp. (12, 13), and Escherichia coli (5, 11). Likewise, in other species,

O/E/EpO have been associated with many different agents such as Brucella ovis,

Histophilus ovsi, Arcanobacterium pyogenes, and Actinobacillus seminis in sheep (1, 4),

Brucella abortus, Actinomyces pyogenes, Mycobacterium tuberculosis in bulls (1),

Staphylococcus aureus, Escherichia coli and Proteus spp. in camels (16), and Chlamydia

trachomatis, Escherichia coli, Staphylococcus spp., and Neisseria gonorrhoeae, among

others, in humans (6, 7, 10). The amount of literature available regarding these

conditions in poultry is scarce. In the present study, two cases of orchitis are described, a

unilateral infection caused by S. aureus, and a bilateral case of epididymo-orchitis due to

E. coli.

CASE HISTORY

Case 1. During a male fertility check in which 10 male broiler breeders with

characteristics of infertility from were taken for necropsy examination from a normal

fertility house of 62 week-old broiler breeders, a bird with an abnormal testicle was

discovered.

Case 2. A male broiler breeder with abnormal testicles was found in a 28 week-

old broiler breeder flock that was experiencing increased mortality. The rooster was

5

among the birds found dead on the morning the flock was visited. It was the only male

with testicular lesions among 7 dead males that were examined.

RESULTS

Necropsy and gross pathology. Birds that were either culled in Case 1 or found

dead in Case 2 were examined for gross lesions. Upon necropsy of the 10 affected birds

in Case 1, 8 (80%) had no gross lesions, 1 (10%) had small testicles, and 1 (10%) had

unilateral orchitis. The affected testis was irregularly shaped, edematous, swollen,

yellowish in color, have fibrin on the surface, and displayed prominent vessels (Figure 1).

No other gross lesions were noted in the bird. In Case 2, 7 birds were necropsied: 3

(43%) had hip degeneration, 3 (43%) had a blocked larynx (choke), and 1 (14%) had

bilateral orchitis. The affected testes were irregular, edematous, swollen with extended

depressed areas, prominent vessels and multiple petechiae were present on the tunica

albuginea (Figure 2). On cut section, they exhibited characteristic deep dark depressed

multifocal areas. The bird was thin, dehydrated, and lacked normal body fat stores. The

cloaca was distended, and skin between the cloaca and ventral abdomen was ulcerated.

Internally, inflammatory lesions were not identified in any tissues other than the testicles.

Bacteriology. Swabs were aseptically used to obtain samples for aerobic

bacteriology from affected testicles in both cases. Heavy growth of S. aureus was

recovered in Case 1. Escherichia coli was identified from both the testes and epididymis

in Case 2.

6

Histopathology. Microscopic examination of the affected testis in Case 1

revealed intratubular-interstitial orchitis. A multicentric distribution of necrotic foci was

observed (Figure 3), with approximately 30% of the seminiferous tubules lumina filled

with fibrin, degenerated spermatozoa, heterophils, epithelial debris, macrophages, and

bacterial colonies. The least affected tubules displayed a pink eosinophilic stain material,

consistent with fibrin. Fibrin, immature granulation tissue and collagenous connective

tissue infiltrated by heterophils, lymphocytes, plasma cells, macrophages and

multinucleated giant cells were present in the interstitial tissue between necrotic foci

(Figure 4). A positive blue-staining reaction of intralesional colonies resembling grape-

like clusters were apparent when sections were stained with Gram stain (Figure 5). The

epididymis was not available for histopathology.

Microscopic examination of the affected testes and epididymis in Case 2 revealed

intratubular-interstitial epididymo-orchitis in which a multicentric coalescing distribution

of lesions resulted in inflammation and necrosis of approximately 80% of the

seminiferous tubules (Figure 6). Lumina of affected tubules were filled with fibrin,

degenerated spermatozoa, heterophils, epithelial debris, macrophages, and colonies of

rod-shaped bacteria. Fibrin, immature granulation tissue, and collagenous connective

tissue infiltrated by heterophils, lymphocytes, plasma cells, and macrophages were

present in the interstitial tissue between necrotic foci. No multinucleated giant cells were

observed. The epididymis also displayed multicentric necrotic foci (Figure 7) filled with

fibrin, degenerated spermatozoa, heterophils, epithelial debris, macrophages, and

colonies of rod-shaped bacteria (Figure 8).

7

DISCUSSION

Infertility in male broiler breeders is a serious concern in the poultry industry due

to severe economic losses associated with decreased fertility and productivity. Orchitis,

epididymitis, and epididymo-orchitis are among the leading causes of infertility. Many

cases begin as epididymitis, and progress to epididymo-orchitis (14). The milder forms

will at minimum cause aspermatogenesis, whereas the most severe can potentially

increase mortality due to fatal septicemia. (14)

Both in animals and humans, epididymitis and epididymo-orchitis occur more

commonly than only orchitis (8, 9). Epididymo-orchitis is generally observed as a

unilateral disease (1, 7); however a bilateral case of epididymo-orchitis is presented in

this study. Infectious O/E/EpO can result from two possible routes: hematogenous or

ascending. Orchitis without involvement of the epididymis most often arises by

hematogenous infection (1, 8, 9), whereas epididymitis and epididymo-orchitis, in which

organisms travel along and invade the different components of the genital tract, are most

commonly considered ascending infections (1, 8, 14, 15).

We believe that both cases described in this study occurred via the ascending

route. Despite the lack of epididymis in Case 1, the unilateral nature of the disease makes

the hematogenous route unlikely. Availability of the epididymis and evidence of

epididymo-orchitis would have been helpful to corroborate an ascending infection.

In Case 2, ulceration of the abdominal skin and a distention of the cloaca were

observed during necropsy, suggesting an underlying condition affecting the cloaca that

could have predisposed microorganisms to colonize and ascend the ductus deferens.

8

Involvement of the epididymis in the same process as the testicle also supports the

likelihood that the orchitis resulted from coliforms located in the cloaca.

Infectious orchitis and epididymo-orchitis are poorly described diseases in poultry

literature, with only a few references available (5, 11, 12, 13). These publications

reported E. coli and Salmonella spp. as the causative agents of the disease. We could not

locate references to S. aureus, as a cause of orchitis in poultry. Pyogranulomatous orchitis

due to E. coli has been described previously (5), but not as a bilateral epididymo-orchitis.

Both microorganisms are commonly found in poultry environments, and have pathogenic

capacity (2, 3). This study shows that common environmental organisms can cause

O/E/EpO in male broiler breeders via the ascending route.

Prevalence of O/P/EpO in the studied males seemed to be low; 10% in Case 1 and

14% in Case 2. However, further studies should be conducted in order to understand the

occurrence of O/E/EpO and its role in reproductive performance.

In summary, a case of infectious orchitis and a case epididymo-orchitis, both of

which most likely occurred via an ascending route of infection, are presented in this

paper. A novel isolation of Staphylococcus aureus as a testicular pathogen in poultry,

and an ascending bilateral epididymo-orchitis due to E. coli were identified. Despite low

prevalence of disease, sufficient evidence has been presented to recommend considering

infectious O/E/EpO in the differential diagnoses of male broiler breeder fertility problem.

REFERENCES

1. Acland, H. M. Reproductive System: Male. In: Thompson's special Veterinary

Pathology. M. D. MacGavin, W. W. Carlton, J. F. Zachary, eds. Mosby Inc., St. Louis,

MS. pp. 635-652. 2001.

9

2. Andreasen, C. B. Staphylococcosis. In: Diseases of poultry, 11th Ed. Y. M. Saif,

H. J. Barnes, J. R. Glisson, A. M. Fadly, L. R. McDougald, D. E. Swayne, eds. Iowa

State Press, Ames, IA. pp. 798-804. 2003.

3. Barnes, H. J., J. P. Vaillancourt, and W. B. Gross. Colibacillosis. In: Diseases of

poultry, 11th Ed. Y. M. Saif, H. J. Barnes, J. R. Glisson, A. M. Fadly, L. R. McDougald,

D. E. Swayne, eds. Iowa State Press, Ames, IA. pp. 631-656. 2003.

4. Burgess, G. W. Ovine contagious epididymitis: a review. Vet Microbiol. 7:551-

575. 1982.

5. Herenda, D. C., D. A. Franco. Poultry diseases and meat hygiene: a color atlas.

Iowa state university press, Ames, Iowa. pp.105. 1996.

6. Holmes K. K., Berger R. E., Alexander E. R. Acute epididymitis: etiology and

therapy. Arch Androl. 3:309-316. 1979.

7. Holmes, K. K. Sexually transmitted diseases: overview and clinical approach. In:

Harrison's Principles of Internal Medicine, 15th Ed. Braunwald E., A. S. Fauci, D. L.

Casper, S. L. Hauser, D. L. Longo, and J. L. Jameson. McGraw-Hill. CD-ROM Ed.

Chapter 132. 2001.

8. Krieger J. N. Epididymitis, orchitis, and related conditions. Sex Transm Dis.

11:173-181. 1984.

9. Ladd, P. W. The male genital system. In: Pathology of Domestic Animals, 3rd Ed,

Volume 3. K. V. F. Jubb, P. C. Kennedy, and N. Palmer, eds. Academic Press Inc.,

Orlando, FL. pp. 409-459. 1985.

10. Melekos M. D., and H.W. Asbach. Epididymitis: aspects concerning etiology and

treatment. J Urol. 138:83-66. 1987.

10

11. Randall, J. R., and R. L. Reece. Color Atlas of Avian Histopathology. Mosby-

Wolfe, London, UK. pp. 211-212. 1996.

12. Shivaprasad, H. L. Fowl typhoid and pullorum disease. In: Diseases of poultry:

world trade and public health implications. C. W. Beard, and M. S. McNulty, eds. Rev.

sci. tech. Off. int. Epiz.19(2):405-424. 2000.

13. Shivaprasad, H. L. Pullorum disease and fowl typhoid. In: Diseases of poultry,

11th Ed. Y. M. Saif, H. J. Barnes, J. R. Glisson, A. M. Fadly, L. R. McDougald, D. E.

Swayne, eds. Iowa State Press, Ames, IA. pp. 568-582. 2003.

14. Smith, A. T., T. H. Jones, R. D. Hunt. Veterinary Pathology, 4th Ed. Lea &

Febiger, Philadelphia, PA. pp. 1136-1137.1972.

15. Sobel J. D. New aspects of pathogenesis of lower urinary tract infections.

Urology. 26(Suppl):11-16. 1985.

16. Yagoub, S. O. Bacterial diseases of the reproductive system of camels (Camelus

dromedarius) in Eastern Sudan. J. An. Vet. Adv.. 4:642-644. 2005.

ACKNOWLEDGMENTS

The authors would like to thank Dr. Michael Martin for his involvement in this work, and

Miss C. Germain for her editorial assistance.

Figure legends.

Figure 1. Case 1, 62-wk broiler breeder, orchitis. Testicle is irregularly shaped,

edematous, swollen, yellowish color with prominent vessels and fibrin on the surface.

The opposite testicle was normal. .

Figure 2. Case 2, 28-wk broiler breeder, epididymo-orchitis. Irregular, edematous,

swollen testes with extended depressed areas, prominent vessels, and multiple petechiae

on the tunica albuginea.

Figure 3. Case 1, 62-wk broiler breeder, orchitis. Intratubular-interstitial orchitis.

Multicentric necrotic foci. H&E. Bar = 0.5 mm.

Figure 4. Case 1, 62-wk broiler breeder, orchitis. Seminiferous tubules filled with fibrin,

degenerated spermatozoa, heterophils, epithelial debris, macrophages, and colonies of

bacteria. H&E. Bar = 100 µm.

Figure 5. Case 1, 62-wk broiler breeder, orchitis. Positive blue staining reaction of

intralesional bacterial colonies. Gram. Bar = 25 µm.

Figure 6. Case 2, 28-wk broiler breeder. Intratubular-interstitial orchitis. Multicentric

coalescing necrotic foci. H&E. Bar = 0.5 mm

Figure 7. Case 2, 28-wk broiler breeder. Epididymitis. Multicentric necrotic foci. H&E.

Bar = 0.5 mm

Figure 8. Case 2, 28-wk broiler breeder. Epididymitis. Foci filled with fibrin, degenerated

spermatozoa, heterophils, epithelial debris, macrophages, and colonies of rod-shaped

bacteria. H&E. Bar = 25 µm.