the occurrence of dioctophymiasis in the Maned wolf Chrysocyon brachyurus

E. A. MATERA: A. M. S A L I B A 2 & A. M A T E R A 3

Sao Paulo, and Director, Veterinary Department, Sao Paulo Zoo, Brazil

Brazil

Professor of Pathology, Clinical Surgery and Obstetrics, Veterinary Faculty, University of

Assistant Professor of Pathological Anatomy, Veterinary Faculty, University of Sic0 Paulo,

veterinarian, si2o Paado zoo, Brazil

INTRODUCTION

The parasite Dioctophyme renale (Goeze, 1782) belongs to the family Dioctophymoidae and is found in the mammalian kidney. Its synonyms are: Eustrongylus gigas (Diesing, 185 I), Strongylus renale (Mopuin-Tandon, 1869), and Eustrongylus visceralis (Raillet, 1885). The measurements of the adult parasite are as follows: male 14-40 cm by 4-6 mm; female 20--100 cm by 5-12 mm. The parasites are blood red in colour and have trans- verse stripes. The female tapers at both ends and the posterior extremity of the male is characterised by the presence of a spicule.

In wild animals the parasite was first described in Allamand’s grison Galictis vitfata by Lutz (1901, 1924, 1925). Dacorso Filho et al. (1954) also described it in the same species. It was found in the coati Nasua nasua by Lutz (1924)~ while Rocha et al. (1965) found it in the Two-toed sloth Choloepus didactylus. The parasite was first recognised in the Maned wolf Chrymcyon brachyurus by Molin (1860). Subsequently Giovannoni and Molfi (1960) also reported three cases of dioctophymiasis in this species. The most recent reports are those given by Lamina and Brack (1966) and Faust and Scherpner (1967). Santos (1945) concludes from the literature that Maned wolves in captivity have also died from infesta- tion with Dioctophyme renale.

In this paper we are reporting on five cases of dioctophymiasis in Maned wolves kept in captivity.

PERSONAL OBSERVATIONS

All the affected animals were adults. A severe diarrhoea was present as the result of a gastro-intestinal disturbance causing listlessness. They were restless throughout the night, and they often fought with each other. In the absence of clinical investigation owing to the practical difficulties involved, the only clinical signs observed were marked irritation of the skin and shedding of hair. In the pelage tumours of various sizes were found. Faecal

C A N I D S AND FELIDS IN C A P T I V I T Y 25

examinations of all five specimens were made regularly and urine tests were carried out on two of the animals. The urine was centrifuged (1,500 rpm) for five minutes. Micro- scopic examination of the sediment showed eggs of Dioctophyrne renale.

Later at post-mortem examination the animals were found to be very thin and there were many injuries all over the body, in addition to pronounced gastritis and enteritis. In two cadavers the right kidney did not exist and in the abdominal cavity we found several nematodes. In three other cases the parasites were found in the renal pelvis, resulting in atrophy by pressure on the surrounding tissue. The kidneys were hard and a metallic noise was audible when they were cut with a knife. In one case the kidney had changed to a cyst filled with fluid and two parasites.

In all specimens the left kidney was enlarged and obvious signs of compensating hyper- trophy were shown.

Histological section of the infested kidneys showed that where the renal tissue still existed there was an increase of connective tissue, consisting mainly of collagen fibres in the interstitial tissues and within the fibrous capsule. In the lesions we found histiocytes, lymphocytes and plasma cells. Some glomeruli were normal in appearance, while others were distended and contained an homogenous substance which stained pink with eosin. Others were perfectly translucent. Hyaline casts were observed in the tubules. Part of the renal pelvis was normal while other areas, including the medullary zone, were damaged showing haematomatous and necrotic areas. In the most damaged parts only a small amount of parenchymatous tissue and proliferated connective tissue, consisting of collagen and reticulated fibres, remained. Within this tissue traces of tubules containing many hyaline casts and glomeruli were found. The left kidney was hypertrophied and contained enlarged tubules. In general, the kidney cells were flattened.

D I S C U S S I O N

All the Maned wolves which died in the Sao Paulo Zoo were infested with Dioctoplzynte renale and therefore this parasite seems to be common in the species. It is believed that fishes and molluscs are the intermediate hosts of the parasites. Gomes de Moraes (ex Santos, 1945) believes that the parasite is transmitted through eating infested fish, especially Lambaris and Acaras. These fish contain the parasite’s larvae and are regularly thrown ashore during the flooding of the rivers. Here they are found and eaten by the Maned wolves. Most authors who have investigated this parasite in the dog demonstrated that the right kidney is infested in almost every case (Dacorso Filho et al. 1954; Molin, 1860; Monteiro, 1934). In the interesting paper by Giovannoni and Molfi (1960), describing three cases of dioctophymiasis in the Maned wolf, the parasites were nearly always found in the right kidney. We have found the same to be true in all five cases. Some authors have tried to explain the phenomenon. Stefanksy and Strankowsky (1936) write (translated) : ‘The larvae of Dioctophyme renale are swallowed, enter via the vascular system and into the liver, penetrate the liver and renal capsule and finally reach the renal pelvis, where

26 CANlDS AND FELIDS IN CAPTIVITY

further development takes place.’ Both authors believe that the right kidney is more susceptible than the left one because it is nearer to the liver; this, however, is not generally accepted.

The parasite influences the animal’s condition by damaging the kidney. Because of the difficulties of investigating our animals clinically we were only able to record an itching irritation and shedding of hairs; and tumours of various sizes in the pelage. The same symptoms (in addition to regurgitation, lack of thirst, and retention of urine) were observed in the dog by Migliano and Matera (1966).

The diagnosis of the infestation is easy by taking a urine sample with a bladder- catheter. Both times we did this we found eggs of Dioctophyyme reitale in the sediment of the urine. Unfortunately, we were unable to make the same test on the three other animals. Migliano and Matera (1966) employed urography, using Hypaque (3,s- diamylacetat-~,q,6-triod-sodiumbenzoat) in association with pneumoperitoneum, in addition to urine sediment examination, in the diagnosis of this condition in the dog. The treatment consisted of nephrectomy, and this resulted in recovery.

Obviously, dioctophymiasis in the Maned wolf is a serious problem in the zoo because the species is rare and valuable and the parasite is common and fatal. We consider that in order to control this disease, the urine sediment should be examined and when the parasite is present the infested kidney should be removed.

SUMMARY

The authors describe in this paper the occurrence of five cases of dioctophymiasis in Maned wolves Chrysocyon bvachyzirus belonging to Sao Paulo Zoo. Clinical symptoms are described and the lesions found at post-mortem examination are noted. Agreeing with the veterinary literature on the subject, they also verify that the infestation is in the right kidney. Finally, they show the possibility of diagnosis by radiography and treatment by nephrectomy.

R E FE I< E NCE S

D.4COKSO FILHO, P., LANGENER, J. and DOBEREINER, J. (1954): Sobrc a infeSta@O C k S O & por L)iocto- phyme renale (Goezc, 1782) em cIes. Veterinavia, Rio de3. 8(2): 35.

FAUST, R. and S C H E R P N E R , c. (1967): A note on the gestation period of the hlancd wolf Clirysocyon hrachyurus at Frankfurt Zoo. Ivt. Zoo Yb. 7: 119.

GIOVANNONI, M. and MOLFI, A. (1960): 0 Dioctoplzyme rennle (Goeze, 1782) no Brasil. An. Fuc. M e d . Parana 3(1, 2): 99.

L A M I N A , J. and B R A C K , M. (1966): Der Nierenwurm-Dioctophyme male (Goezc, 1782, Stiles 1901) als Todesursache bei einem Mahnenwolf (Chrysocyon jubatus). Z. ParasitKde, 27(4) : 336-340. LUTZ, A. (1901): iiber einen Befund von Eustrongylus gkas in einem neuen Wirt. Zentbl. Bakt. Parasit- Kde ag(6): 256-257.

Hypaque, Winthrop Products, Inc.

CANIDS AND F E L I D S I N C A P T I V I T Y 27

LUTZ, A. (1924): Sur le Diocrophyme renalis. C. r. Sianc. SOL. Bid . 90: 696.

LUTZ, A. (1925): Dioctophyme renah (Eustrongylus gkas). c. Y . SLanc. sac. Bid. 93: 39-40.

MIGLIANO, M. F. and MATERA, E. A. (1966): Dioctorfimose em Canis fumiliaris. Esrudos sfin. wed. cirurg. cam. Notas prelim,

AIOLIN, c. (1860) ex. P R O E N C A c. (1935): Sobredoiscasos de Dioctophyine renaleem cio no Rio de Janeiro. Bol. Vet. Exercito ~ ( 3 ) : 50.

hlONTEIRO, A. C. (1934). Eustrongilose do d o . Bol. Vet. Exercito I@): 191.

ROCHA, u. F., SERRA, R. G. and GRECCHI, R. (1965): Parasitism0 por Dioctophyme renale (Goeze, 1782) em Preguica Choloepus didactyhs Linnaeus, 1758. Revta Fac. Farm. Bioquiin. S. Paula, 3(2): 325. SANTOS, E. (1945): Entre oganzbli e o tnacaco. 1st ed. Rio de Janeiro: F. Briquet.

STEFANSKY, w. and S T R A N K O W S K Y , (1936): Sur un cas de pCnCtration de StrongylegCant dans le rein droit du chien. Annls. Parasir. hum. comp. 14(1): 35.

breeding the Cape Hunting dog Lycaon pictus

a t Amsterdam Zoo D. DEKKER Biologist, Natura Artis Mngistra, Arnsterdum, Netherlands

In April 1964 the Amsterdam Zoo received a pair of Cape Hunting dogs Lycaon pictzis from Okahandja Zoopark in South-West Africa. They are housed in an outdoor enclosure, 17 ni long and 5 m wide, with a sandy floor. The enclosure is overshadowed by high trees and is situated on the northern side of a three-storeyed building in which there is a closed indoor den adjoining the enclosure. The den has a surface area of 6 sq. m and it has a barred grating on one side which can be screened with metal sheets if total seclusion is desired. The Hunting dogs use the den for sleeping in at night; they are also fed in it.

Since its arrival at the zoo each animal eats about 14 kg of meat with bone daily. A mixture of vitamins and minerals specially made up for carnivorous animals (Carnicon, manu- factured by Trouw en Co, Putten, Netherlands) is added to the meat in the proportion of 20 g per kg meat. Particular attention is paid to see that the animals receive sufficient vitamins A and D, and a balanced proportion of the minerals calcium and phosphorus. The Hunting dogs are only occasionally given a whole chicken or whole pigeon.