Avian Pathology Eye lesions in pet birds

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Nov 12, 2007 - conjunctival cryptosporidiosis, corneal dystrophy, keratitis, corneal ..... lens fibres formed constantly throughout life become compressed into.
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Eye lesions in pet birds a

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b

S. S. Tsai , J. H. Park , K. Hirai & C. Itakura

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Department of Comparative Pathology, Faculty of Veterinary Medicine , Hokkaido University , Sapporo 060, Japan b

Department of Veterinary Microbiology, Faculty of Agriculture , Gifu University , Yanagido, Gifu, 501–11, Japan Published online: 12 Nov 2007.

To cite this article: S. S. Tsai , J. H. Park , K. Hirai & C. Itakura (1993) Eye lesions in pet birds, Avian Pathology, 22:1, 95-112, DOI: 10.1080/03079459308418903 To link to this article: http://dx.doi.org/10.1080/03079459308418903

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Avian Pathology (1993) 22, 95-112

Eye lesions in pet birds S. S. TSAI,1 J. H. PARK,1 K. HIRAI2 & C. ITAKURA1 1

Department of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060 and 2Department of Veterinary Microbiology, Faculty of Agriculture, Gifu University, Yanagido, Gifu 501-11, Japan

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SUMMARY Amongst eye lesions in birds that died in quarantine, cataracts were the most common disorders (37/241, 15.4%), being prevalent in the annular pads of cockatiels (Nymphicus hollandicus), Amazon parrots (Amazona aestiva aestiva) and budgerigars (Melopsittacus undulatus). The incidence in male birds was more than twice that in females. Deposition of crystals, mostly in the cornea, was the second most frequent lesion (21/293, 8.7%), mainly found in cockatiels, parakeets (Psittacula krameri manillensis), Amazon parrots (Amazona aestiva aestiva), budgerigars and finches (Poephila gouldiae gouldiae). These corneal crystals were negative to PAS and Kossa's stains. Six parakeets (Psittacula krameri manillensis) had calcium salts deposited in the inner plexiform layer of the retina and occasionally in the iris and ciliary body. Neither inflammation nor neo-vascularization was observed when cataracts, corneal crystalline deposition, and retinal and ciliary calcification were present. Intranuclear inclusion bodies typical for papovavirus infection were found in the eyelids of six budgerigars (2.5%). Similar inclusions were simultaneously found in the pars ciliaris retinae (4, 1.7%), inner plexiform of retina (1, 0.4%) and anterior epithelium of the cornea (1, 0.4%). Other lesions such as candidial endophthalmitis, conjunctival cryptosporidiosis, corneal dystrophy, keratitis, corneal perforation and iridocyclitis, were occasional findings.

INTRODUCTION The eyes of birds and mammals give some indication of the body condition. They react to local and systemic infections or disorders. Therefore, the detection of eye lesions may be helpful in diagnosis of certain diseases. Among domestic animals, the eyes of the dog have received most attention (Mustaffa-Babjee, 1969). Most of the earlier reports on the disorders of avian eyes are confined to poultry and attributed to infectious agents, toxaemia, poisoning, nutritional deficiency, and congenital and hereditary defects. Only a few reports concerning eye lesions of non-domesticated birds are present in the scientific literature (Frost, 1961; Keymer, 1977; Tudor, 1978).

Received 21 April 1992; Accepted 13 July 1992.

95

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S. S.TSAl BTAL.

The purpose of this study is to describe some of the pathological alterations in the eyes of psittacine and passerine birds.

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MATERIALS AND METHODS A total of 241 young adult and adult birds of non-domestic species was examined for this study. They consisted of 52 cockatiels (Nymphicus hollandicus), eight lovebirds (Agapornis roseicollis), 19 Amazons (Amazona aestiva aestiva), 10 African Greys (Psittacus erithacus), 47 budgerigars (Melopsittacus undulatus), 67 parakeets (Psittacula krameri manillensis), two rosellas (Platycercus emimius), 18 lories (Trichoglossus haematod) and 18 finches (Poephila gouldiae gouldiae). The birds died during 2 weeks of quarantine in a bird shop after arrival in Japan from several foreign countries, mainly located in Asia. For histopathological examination, tissue samples were fixed in 10% buffered formalin, embedded in paraffin, sectioned, and stained with haematoxylin and eosin (H&E), Kossa's method for calcium, and periodic acid-Schiff reaction (PAS). RESULTS Based on histological examination, cataracts were the most frequent disorder in the eyes of pet birds (37/241, 15.4%). They involved cockatiels (18/52, 34.6%), finches (Poephila gouldiae gouldiae) (5/18, 27.8%), budgerigars (9/47, 19.1%), parakeets {Psittacula krameri manillensis) (4/67, 6.0%) and Amazon parrot (Amazona aestiva aestiva) (1/19, 5.3%). Both sexes were involved. The male was more susceptible than the female (64.9:35.1%). Generally, the annular pads had higher incidence and more severe lesions than the lens bodies (Table 1). Most of the lesions were observed in both equators of the annular pad, and less frequently in the anterior and posterior cortical lens fibres. In spite of the lesion distribution, the basic cataract lesions were similar. Affected lens fibres showed degenerative changes, and became fragmented and liquefied (Figure 1). The degenerative fibres were turned to Morgagnian globules, characterized by swollen, round fragments with deep eosinophilic staining. Adjacent to the lesions, the lens fibres sometimes appeared as bladder cells, which were swollen and spindle shaped, with retained nuclei. Focal proliferation of lens epithelial cells was found in the subcapsular regions of the annular pads and lens body (Figure 2). Occasionally, lens epithelial nuclei had migrated posteriorly beyond the equators to lie adjacent to the posterior lens capsule. Several lens bodies had numerous variable vesicles, which contained eosinophilic amorphous and granular material (Figure 3). These substances were similar to the protein of lens fibres. Neither inflammatory reaction nor neo-vascular formation was noticed in the cataract lens. The disorders of cornea included crystalline deposition (21, 8.7%), corneal dystrophy (1, 0.4%), acute and chronic keratitis (1 each, 0.4%), corneal perforation (1,0.4%) and papovavirus infection (1,0.4%). Corneal deposition of crystals

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Table 1. Lesion distribution of cataracts Annular pad Case no.

Sex

4319 4321 4330 4334 4335 4337 4338 4340 4344 4348 4349 4350 4352 4354 4357 4358 4359 4360

M" M F» M M M M M M M M M F M M M F F

4392 4395 4397 4399

M F F M

Parrots

4416

F

Budgerigars

4401 4439 4449 4468 4469 4470 4471 4479 4487

M M M M F F M M F

4494 4531 4537 4538 4543

M M F F F

Bird

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Cockatiels

Parakeets

Finches

1

Equator

Anterior

Posterior

Upper

Lower

+*

+* +* +* — + — — — +* +* — — +* +

+* +* +* — — — — — — — — — — +* —

+* +* +* +*

+* +* +* + + +* +* +* +* + +* +*

+* + + +* + +* +* +* + +* +*

NE

NE

+* + +*

+* — +*

NE

NE — — — NE

NE

NE

+* + +* +*

+* + +* —

+* + +*

+* + +* — +*

— — —

+*

NE

NE

NE

NE

+* — — + — +* — —

+* — — + — + — —

+* +* +* + +* + — +

+* +* +* + +* + + +

NE NE —

NE NE —

NE NE —

NE NE —

Lens body e

— — — — V — V — — — —

+ + — V —

+ V — V —

+* * — — V — — — —

+ +* +*

"M: male; *F: female; c + : degeneration; d*: liquefaction; e—: no lesion; ^NE: not examined; v: vesicle.

was frequently encountered in this study (Table 2). The affected birds included cockatiels, finches (Poephila gouldiae gouldiae), Amazon parrots (Amazona aestiva aestiva), parakeets (Psittacula krameri manillensis) and budgerigars. Both sexes were affected. The prominent lesion was multifocal depositions of crystals in different parts of the cornea (Figure 4). In all cases, neither cellular infiltration nor neovascularization was evoked, except one which coincidentally showed

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Figure 1. Cataract in cockatiel. The lens fibres of annular pad are swollen, rounded, deeper eosinophilic and liquefied. (H&E. Bar =100 /urn.)

L Figure 2. Cataract in budgerigar. The lens fibres of annular pad are swollen, individualized and associated with an increase of epithelial nuclei. (H&E. Bar = 50 pun.)

chronic keratitis. The crystals were brick-like in shape, and coloured light purple in H&E stained sections. They showed negative reaction to PAS and Kossa's stains. The frequencies of incidence were as follows: stroma (17/21,

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Figure 3. Cataract in finch. Many various sizes of vesicles appear in the lens body. Eosinophilic amorphous and granular material accumulates in the vesicles. (H&E: Bar = 100 fim.)

Figure 4. Comeal crystalline deposition in budgerigar. Brick-like crystals are deposited multifocally in the anterior epithelium, Bowman's membrane and stroma of cornea. Note no cellular reaction in the neighbouring tissue. (H&E. Bar =100 jxm.)

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81.0%) > anterior epithelium (14/21, 66.7%) > Bowman's membrane (11/21, 52.4%) > Descemet's membrane (6/21, 28.6%) > posterior epithelium (5/21, 23.8%). Occasional crystal deposition was simultaneously observed in other areas such as sclera, iris and bulbar conjunctiva (Figure 5). Table 2. Crystalline deposition in the eyes Cornea Case no.

Sex

AE"

4313 4322 4327 4337 4344 4345 4348 4358 4359

M' M M M M M M M F*

+*

Parakeets

4376 4381 4389

F F F

Parrots

4416 4419 4431 4434

F F F M

Budgerigars

4470 4479

F M

Finches

4494 4534 4567

M M M

Birds

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Cockatiels

BM*

DE'

PE*

Others

Iris Sclera Sclera Sclera Sclera

Iris Conjunctiva

Conjunctiva

"AE: anterior epithelium; 'BM: Bowman's membrane; CSM: stroma; rfDE: Decemet's membrane; 'PE: posterior epithelium; 'M: male; *F: female; * + : positive;'—: negative.

Corneal dystrophy was found in a male parakeet {Psittacula kraemeri manillensis). Histological examination revealed numerous vacuoles of variable sizes developed in the superficial layer of the anterior epithelium and in the outer stroma (Figure 6). Some vesicles in the anterior epithelium were ruptured. The inner stroma was thickened by oedema. Both Descemet's membrane and the posterior epithelium were intact. One female parakeet {Psittacula kraemeri manillensis) had conjunctival cryptsporidiosis associated with acute keratitis, severe iriditis, conjunctivitis and cataract (Figure 7). The corneal lesion was characterized by loss of the anterior epithelium and diffuse infiltration of the stroma with heterophils, particularly concentrated on the area underlying the Bowman's membrane. Stromal oedema was evident. The inner stroma had more severe oedema than the outer and showed a spongy appearance. The protozoa had a positive reaction to PAS stain. One budgerigar showed chronic keratitis. This was characterized by the formation

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S^S^^^S^i

Figure 5. /nda/ crystalline deposition in Amazon parrot. Many crystals are deposited in the iris and replace some of the iridal muscles. (H&E. Bar = 50 jum.)

Figure 6. Corneal dystrophy in parakeet. Numerous vesicles appear in the anterior epithelial layer and the anterior stroma. Some of them are ruptured. The stroma shows loose arrangement. (H&E. Bar = 50 fim.)

of neovascularization and moderate infiltration of chronic inflammatory cells (Figure 8). The associated changes included stromal oedema and hyperplasia of the anterior epithelium. Corneal perforation was encountered in one male parakeet (Psittacula krameri

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^ ? ^ ? ^ ^ ^ - - --•

^!!#6r

Figure 7. Conjunctival cryptosporidiosis in parakeet. Ovoid protozoa are attached to the mucosal layers of conjunctiva. The mucosal epithelium is hyperplastic, associated with mild infiltration of heterophils and plasma cells in the lamina propria. (H&E. Bar = 25 pun.)

-

. ;

Figure 8. Chronic keratitis in budgerigar. Neo-vascular formation and infiltration of chronic inflammatory cells are seen in the stroma of cornea. Overlying epithelial cells show hyperplasia. (H&E. Bar =100 fim.)

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,1

Figure 9. Corneal perforation in parakeet. The cornea shows neo-vascular formation and accumulation of inflammatory exudates. The edge of the perforation is covered by the hyperplastic anterior epithelium (arrowheads). The associated change is severe iriditis (arrow). (H&E. Bar = 100 \im.)

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Figure 10. Retinal calcification in parakeet. Zonal deposition of calcium salts is seen in the inner plexiform layer. The salts showed positive reaction to Kossa's stain. (H&E. Bar = 50 /urn.)

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manillensis). The affected cornea was thickened due to chronic inflammation. Overlying anterior epithelium showed irregular proliferation and extended to cover the margins of the perforation (Figure 9). Inter-epithelial oedema with formation of bulla was found in many locations. Neo-vascular growth was evident by invasion of capillaries from the limbus into the avascular stroma. There were two different tissue reactions found in the same tissue section. The outer stroma consisted of immature granulation tissue. Many newly-formed capillaries and fibroblastic tissues were established, accompanied by slight infiltration of heterophils, lymphocytes and plasma cells. The inner stroma not only had many capillaries, but also showed severe oedema and cellular reaction. There appeared to be a cellular infiltration mainly plasma cells and lymphocytes between the two zones. Both Descemet's membrane and the posterior epithelium were not discernible. Severe iridocyclitis and conjunctivitis were also detected in this eye. Retinal calcification was observed in six parakeets (Psittacula krameri manillensis) including three males and three females, the deposition site being zonally distributed. The calcium salts ranged from small granules to large plaques and were found only in the inner plexiform layer (Figure 10). The deposits showed positive reaction to Kossa's stain. Neither neo-vascularization nor inflammation was found in the neighbouring tissues. One parrot (Amazona aestiva aestiva) had a bacterial infection, involving the choroid, retina and vitreous body. The choroid was thickened due to an accumulation of inflammatory exudates. The blood vessels were hyperaemic. In the suprachoroid layer there was a massive accumulation of eosinophilic fluid mixed with a few inflammatory cells. In the inner region between the choroid and the retina, there were large aggregations of heterophils and macrophages. Large numbers of bacteria covered the inflammatory area and diffusely invaded the retina leading to its detachment and disintegration (Figure 11). Most pigmented epithelial cells had disappeared and were replaced by bacterial clumps. The nuclei of cones and rods were somewhat swollen and rounded and showed deeper eosinophilic staining. At one point, the retina was completely destroyed and replaced by large amounts of inflammatory exudates and bacterial clumps (Figure 12). The vitreous body was filled with heterophils and massive numbers of bacteria in the region adjacent to the retina. In the opposite area, neighbouring the lens side, there was proliferation of numerous fibroblasts. An inflammatory zone consisting of heterophils and macrophages developed between the two regions (Figure 13). Lens fibres showed degenerative changes and an increase of nuclei. One budgerigar had candidial infection in the lens and vitreous body. Both bodies were almost completely destroyed and lost their normal structure. Many blastospores showed a positive reaction to PAS stain and were embedded in the necrotic tissues (Figure 14). Cellular responses were minimal. In two parrots {Amazona aestiva aestiva) the eyes showed iridocyclitis. The iris and ciliary body were heavily infiltrated by inflammatory cells, most of which were heterophils and plasma cells. In an advanced case, neo-vascular proliferation was evident with a predominance of plasma cells and lymphocytes in the inflammatory reaction. Three parakeets (Psittcula krameri manillensis) showed

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Figure 11. Retinochoroiditis in Amazon parrot. Large numbers of heterophils, macrophages and bacterial clumps aggregate in the choriocapillary layer, leading to detachment of the retina. There is muck eosinophilic material associated with a few inflammatory cells in the superchoroid layer. (H&E. Bar = 20 fim.)

Figure 12. Retinitis in Amazon parrot. The retina is lost and replaced by inflammatory exudate. Numerous heterophils, macrophages and bacteria are present in the inflammed retina. (H&E. Bar = 50 fim.)

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Figure 13. Bacterial endophthalmitis in Amazon parrot. An inflammatory zone separates the vitreous body into two parts. The left side is filled with immature granulation tissue and bacteria. The right side shows oedematous change with mild infiltration by inflammatory cells. (H&E. Bar = 50 urn.)

Figure 14. Candidial endophthalmitis in budgerigar. The vitreous body shows necrotic change and contains many candidial blastospores and a few inflammatory cells. (H&E. Bar =100 fim.)

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deposition of calcium salts in the iris, and one in the ciliary body and ciliary processes (Figure 15). Lesions in iris striated musculature were uncommon, but two budgerigars showed Zenker's degeneration of muscle fibres. Adhesion of the degenerative iris to the lens was found in one of the two birds. Six budgerigars had typical intranuclear inclusion bodies for papovavirus infection in the eyelids (Table 3). Large pale or lightly basophilic inclusions were present in the germinatival cells of eyelids (Figure 16). Similar but smaller inclusion were found in the pars ciliaris retinae (four cases), the inner granular layer of retina (one) and the anterior epithelium of the cornea (one) (Figure 17). In these lesions there was no inflammatory reaction. Table 3. Intranuclear inclusion bodies in the eye of budgerigars infected naturally with papovavirus Eyelid

Pars ciliaris retinae

Inner granular layer

Anterior epithelium of cornea

69 73

+" +

-* -

-

+ -

96 211 268 272

+ + + +

+ + + +

+

Case no.

-

-

" + : positive; *—: negative.

DISCUSSION Cataracts were the most frequently encountered disorder of the eyes in this study, which were prevalent in cockatiels, finches (Poephila gouldiae gouldiae) and budgerigars. The causes of cataracts are complicated in birds, and include senility (Rigdon et al, 1959; Krehbiel, 1972; Keymer, 1977), viruses (Ridges & Flowers, 1958; Rigdon, 1959), bacteria (Hungerford, 1969), fungi (More, 1953), protozoa (Mustaffa-Babjee, 1969), nutrition (Startup, 1970), trauma (Small & Burke, 1982) and neoplasia (Frost, 1961). In mammals and birds, the most common cause of cataracts is ageing. Nuclear cataracts often occur in senile mammals, whereby lens fibres formed constantly throughout life become compressed into the centre of the lens. In this study, lesions of the annular pads were more common and severe than those of lens bodies. Most of the earlier reports indicated that avian cataract was a secondary manifestation of a primary disease. However, all of our cases had no evidence of previous damage or inflammatory response. There was a higher incidence in males than females. On the basis of these observations, we suggest that the cataracts seen in the present study might be a primary disorder of the lens as described in bobwhite quail (Krehbiel, 1972). Crystalline opacities are a primary disorder of the cornea. There are only a few reports of this condition, most of which are described in dogs (Barnett & Grimes, 1971; MacMillan et al., 1979). The opacities in their cases are round or

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Figure 15. Iridociliary calcification in parakeet. Calcium salts are deposited along the margins of the iris and ciliary processes. Note no cellular reaction adjacent to the deposition site. (H&E. Bar =100 pirn.)

•Sift

it

"j$4r+A

Wm Figure 16. Papovavirus infection of eyelid in budgerigar. The enlarged nuclei of the germinatival cells contain pale-staining inclusion bodies, associated with chromatin margination. Their cytoplasm shows ballooning degeneration. (H&E. Bar = 20 /.im.)

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Figure 17. Papovavirus infection in budgerigar. Several pale-staining intranuclear inclusion bodies are present in the cells of the inner non-pigmented (arrowheads) and outer heavily pigmented layer (arrow) of the ciliary body. (H&E. Bar = 20 fim.)

horizontally oval, consisting of a grey homogenous haze in the anterior stroma or an array of fine polychromatic crystals in the posterior stroma or both. The corneas are not inflammed. Histochemical stainings identify the crystals as a mixture of neutral fats, phospholipids, and cholesterol (MacMillan et al., 1979). We found 21 cases with crystalline deposition in the cornea and occasionally in the sclera, iris and conjunctiva. Unfortunately, the present specimens were not available for histochemical study. Calcification of the eye has been reported in the cornea in bovine malignant catarrhal fever; calcium salts are deposited in the Bowman's membrane (Jubb et al., 1960). High incidence of corneal calcification (187/190) occurs in Japanese mice of the KK strain, which has a high percentage of spontaneous diabetes mellitus (Mittle et al., 1970). However, non-diabetic mice of the CF-1 strain also have a high incidence of the similar disorder (Saunders & Rubin, 1975). In human medicine, metastatic calcification resulting from hypercalcaemia leads to deposition of calcium salts in the Bowman's membrane of the cornea (Smith, 1990). Recently, sclerochoroidal calcification has been studied in 19 patients who have normal calcium metabolism (Schachat et al., 1992). The authors suggest that it is an idiopathic disorder and the occurrence may be more common than has been realized. As far as we know, there are no reports of the deposition of calcium salts in the eyes of birds. In this study, calcification was encountered mainly in the inner plexiform layer of the retina, and less in the iris, ciliary body and processes. There was no evidence of previous tissue damage or inflammatory reaction, providing a hint that it was a kind of metastatic calcification. The

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structure of avian retina is avascular. The mechanism of the retinal calcification in the present birds might be idiopathic as those described in human sclerochoroidal calcification (Schachat et al, 1992). Papovavirus has an affinity for epithelial and lymphoreticular tissues, and endothelial cells (Pass et al., 1987; Tsai, 1987). One of the pathognomonic lesions is the presence of large pale or slightly basophilic intranuclear inclusion bodies in the various organs (Davis et al., 1981; Bernier et al., 1981). Nevertheless, eye lesions caused by papovarvirus infection have rarely been reported, although one described swollen nuclei containing intranuclear inclusion in the iris and at the corneal limbus (Randall et al., 1987). We found similar inclusions in the pars ciliaris retinae, the inner plexiform layer of retina and the anterior epithelium of the cornea in budgerigars. There appear to be no other reports of inclusions in such locations. Humans intra-ocular candidiasis attributed to intravenous drug abuse has occurred and represents one of the most serious and increasingly common complications of drug abuse (Brooks, 1989). In avian medicine, ocular candidiasis has been occasionally reported in ducks (Crispin & Barnett, 1978). We found candidial endophthalmitis in a budgerigar, in which both lens and vitreous bodies were replaced by a mixture of inflammatory exudates (entangled with candidial organisms. Conjunctival cryptosporidiosis was found in a parakeet (Psittacula krameri manillensis). Aside from conjunctivitis, the associated changes included iridocyclitis, keratitis and cataract. Conjunctivitis due to cryptosporidial infection has been reported in birds (Mason & Hartley, 1980; Mason, 1986; Randall, 1986). However, the associated lesions found in the present study need further investigation. Other lesions were occasional findings and less important in practice.

REFERENCES BARNETT, K.C. & GRIMES, T.D. (1971). Verticillate corneal dystrophy in a dog. Journal of Small Animal Practice, 12, 296-299. BERNIER, G., MORIN, M. & MARSOLAIS, G. (1981). A generalized inclusion body disease in the budgerigar (Melopsittacus undulatus) caused by a papovavirus-like agent. Avian Diseases, 25, 1083-1092. BROOKS, R.G. (1989). Prospective study of Candida endophthalmitis in hospitalized patients with candidemia. Archives of Internal Medicine, 149, 2226-2228. CRISPIN, S.M. & BARNETT, K.C. (1978). Ocular candidiasis in ornamental ducks. Avian Pathology, 7, 49-59. DAVIS, R.B., BOZEMAN, L.H., GAUDRY, D., FLETCHER, O.J., LUKERT, P.D. & DYKSTRA, M.J. (1981). A viral

disease of fledgling budgerigars. Avian Diseases, 25, 179-183. FROST, C. (1961). Experiences with pet budgerigars. Veterinary Record, 73, 621-626. HUNGERFORD, T.G. (1969). Diseases of Poultry Including Cage Birds and Pigeons (Sydney, Angus and Robertson Ltd). JUBB, K.V., SAUNDERS, L.Z. & STENIUS, P.I. (1960). Die histologischen Augenveränderungen beim

bosartigen Katarrhalfieber des Rindes. Schweizer Archiv für Tierheilkunde, 102, 392-400. KEYMER, I.F. (1977). Cataracts in birds. Avian Pathology, 6, 335-341. KREHBIEL, J.D. (1972). Cataracts in bobwhite quail. Journal of American Veterinary Medical Association, 161, 634-637. MACMILLAN, A.D., WARING, G.O., SPANGLER, W.L. & ROTH, A.M. (1979). Crystalline corneal opacities

in the Siberian husky. Journal of American Veterinary Medical Association, 175, 829-832.

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MASON, R.W. (1986). Conjunctival cryptosporidiosis in a duck. Avian Diseases, 30, 598-600. MASON, R.W. & HARTLEY, J.W. (1980). Respiratory cryptosporidiosis in a peacock chick. Avian Diseases, 24, 771-776.

Downloaded by [183.250.91.47] at 23:49 26 August 2015

MITTLE, R., GALIN, M.A., OPPERMAN, W., CAMERINI-DAVALOS, R.A. & SPIOR, D. (1970). Corneal

calcification in spontaneously diabetic mice. Investigative Ophthalmology, 9, 137-145. MORE, E.N. (1953). Aspergillus fumigatus as a cause of ophthalmitis in turkeys. Poultry Science, 32, 796-799. MUSTAFFA-BABJEE, A. (1969). Specific and non-specific condition affecting avian eyes. Veterinary Bulletin, 391, 681-687. PASS, D.A., PRUS, S.E. & RIDDELL, C. (1987). A papova-like virus infection of splendid parakeets (Neophema splendida). Avian Diseases, 31, 680-684. RANDALL, C.J. (1986). Conjunctivitis in pheasants associated with cryptosporidial infection. Veterinary Record, 118, 212-221. RANDALL, C.J., LEES, S. & INGLIS, D.M. (1987). Papovavirus-like infection in budgerigars (Melopsittacus undulatus). Avian Pathology, 16, 623-633. RIDGES, C.H. & FLOWERS, A.I. (1958). Iridocyclitis and cataracts associated with encephalomyelitis in chickens. Journal of American Veterinary Medical Association, 19, 79-84. RIGDON, R.H. (1959). Cataracts in chickens with lymphomatosis. American Journal of Veterinary Research, 20, 647-654. RIGDON, R.H., FERGUSON, T.M. & COUCH, J.R. (1959). Spontaneous cataracts in turkeys. American Journal of Veterinary Research, 20, 961-965. SAUNDERS, L.Z. & RUBIN, L.F. (1975). Ophthalmic Pathology of Animals (Switzerland, S. Karger). SCHACHAT, A.P., ROBERTSON, D.M., MIELER, W.F., SCHWARTZ, D., AUGSBURGER, J.J., SCHATZ, H. & GASS,

J.D.M. (1992). Sclerochoroidal calcification. Archives of Ophthalmology, 110, 196-199. SMALL, E. & BURKE, T.J. (1982). Diseases of the organs of special sense. In: PATRAK, M.L. (Ed.) Diseases of Cage and Aviary Birds, 2nd edn, pp. 491-496 (Philadelphia, Lea and Febiger). SMITH, M.E. (1990). Ophthalmic pathology. In: KISSANR, J.M. (Ed.) Anderson's Pathology, 8th edn, pp. 955-984 (Missouri, C. V. Mosby Company). STARTUP, C.M. (1970). The diseases of cage and aviary birds (excluding the specific diseases of the budgerigar). In: ROGERS, A. & NORRIS, K.A. (Eds) Encyclopedia of Aviculture, Volume I, pp. 46-58 (London, Blandford Press). TSAI, S.S. (1987). Pathological studies on natural and experimental infections of budgerigar fledgling disease. The Taiwan Association of Veterinary Medicine and Animal Husbandry, 50, 1-14. TUDOR, D.C. (1978). Retinal Atrophy in a parakeet. Veterinary Medicine/Small, Animal Clinicians, 73, 1456.

RESUME Lésions oculaires chez les oiseaux d'agrément Parmi les lésions oculaires observées chez des oiseaux morts en quarantaine, les cataractes se sont révélés être les troubles les plus fréquents (37/241, 15.4%). Elles sont prévalentes chez les perruches calopsittes (Nymphicus hollandicus), les amazones (Amazona aestiva aestiva) et les perruches ondulées (Melopsittacus undulatus). L'incidence est deux fois plus élevée chez les mâles que chez les femelles. Le dépôt de cristaux, principalement dans la cornée, vient en seconde position (21/293, 8.7%) et se manifeste surtout chez les perruches calopsittes, les perruches (Psittacula krameri manillensis), les amazones (Amazona aestiva aestiva), les perruches ondulées et les pinsons (Poephila gouldiae gouldiae). Ces cristaux cornéens ont des réactions négatives à l'acide périodique de Schiff et aux colorations de Kossa. Six perruches (Psittacula krameri manillensis) présentaient du sel de calcium déposé sur la couche intérieure plexiforme de la rétine et parfois aussi sur l'iris et le corps ciliaire. Lors de la présence des cataractes, du dépôt de critaux dans la cornée et de la calcification retínale et ciliaire, aucune inflammation ou néo-vascularisation n'a été ovservée. Des corps d'inclusion intranucléaires caractéristiques de l'infection à papovavirus ont été trouvés dans les paupières de six perruches ondulées (2.5%). Des inclusions similaires ont été

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trouvées dans les parties ciliaires de la rétine (4,1.7%), dans le plexiforme interne de la rétine (1, 0.4%) et l'épithélium antérieur de la cornée (1,0.4%). Les lésions suivantes ont également été décelées: endophtalmie à candida, cryptosporidiose conjonctivale, distrophie de la cornée, kératite, perforation de la cornée et iridocyclite.

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Augenläsionen bei Ziervögeln Unter den Augenläsionen bei Vögeln, die in der Quarantäne starben, waren Katarakte die häufigsten Störungen (37/241; 15.4%), überwiegend im Ringwulst von Nymphensittichen (Nymphicus hollandicus), Amazonen (Amazona aestiva aestiva) und Wellensittichen (Melopsittacus undulatus). Die Häufigkeit war bei männlichen Vögein mehr als doppelt so groß wie bei Weibchen. Die Ablagerung von Kristallen, meist in der Cornea, war die zweithäufigste Läsion (21/293, 8.7%) und wurde hauptsächlich bei Nymphensittichen, Sittichen (Psittacula krameri manillensis), Amazonen (Amazona aestiva aestiva), Wellensittichen und Finken (Poephila gouldiae gouldiae) gefunden. Diese Corneakristalle reagierten auf PAS- und Kossasche Färbung negativ. Sechs Sittiche (Psittacula krameri manillensis) hatten Ablagerungen von Kalziumsalzen in der inneren plexiformen Shicht der Retina und gelegentlich in der Iris und im Ziliarkörper. Es wurden weder Entzündungen noch Neo-vaskularisierungen beobachtet, wenn Katarakte, Cornea-Kristallablagerungen und Retina- oder Ciliarkörperverkalkungen vorhanden waren. Für eine Papovavirusinfektion typische intranukleäre Einschlußkörperchen wurden in den Augenlidern von sechs Wellensittichen (2.5%) nachgewiesen. Ähnliche Einschlüsse wurden gleichzeitig in der pars ciliaris retinae (4, 1.7%), in der inneren plexiformen Schicht der Retina (I, 0.4%) und im vorderen Epithel der Cornea (1, 0.4%) gefunden. Andere Läsionen wie Candida-Endophthalmitis, Konjunktiva-Cryptosporidiose, Corneadystrophie, Keratitis, Corneaperforation und Iridocyclitis waren vereinzelte Befunde.

RESUMEN Lesiones oculares en aves de compañía Las lesiones más comunes encontradas en aves que murieron durante una cuarentena fueron las oculares (37/241, 15.4%), siendo prevalentes en las almohadillas anulares de las cacatúas (Nymphicus hollandicus), periquitos del Amazonas (Amazona aestiva aestiva) y en los periquitos australianos (Melopsittacus undulatus). La incidencia en las aves macho fue más del doble que en las hembras. El depósito de cristales, principalmente en la córnea, fue la segunda lesión más frecuente (21/293, 8.7%), encontrándola principalmente en las cacatúas, periquitos (Psittacula krameri manillensis), periquitos del Amazonas (Amazona aestiva aestiva), periquitos australianos y pinzones (Poephila gouldiae gouldiae). Los cristales de la córnea fueron negativos a las tinciones de PAS y Von Kossa. Seis periquitos (Psittacula krameri manillensis) tenían sales de calcio depositadas en la capa plexiforme interna de la retina y ocasionalmente en el iris y el cuerpo ciliar. No se observó ni inflamación ni neo-vasculairzación asociadas a cataratas, depósito de cristal en la córnea y calcificación del cuerpo ciliar o de la retina. Se encontraron cuerpos de inclusión intranucleares típicos de una infección por papovavirus en los párpados de seis periquitos australianos (2.5%). Se observaron inclusiones similares de forma simultánea en la pars ciliaris de la retina (4, 1.7%), en la capa plexiforme interna de la retina (1, 0.4%) y en el epitelio anterior de la córnea (1, 0.4%). Otros hallazgos encontrados fueron endoftalmitis por Candida, criptosporidiosis conjuntival, distrofia corneal, queratitis, perforación corneal e iridociclitis.