Circumscribed, ulcerative skin lesions, usually situated caudal to the scapula, affected cattle in the Republic of Venda during the summer of 1981-82. The occurrence of the lesions was associated with heavy infestations of the hornfly, Haematobia meridiana. Microscopically the lesions were characterized by intense eosinophilic dermatitis. Microfilariae were seen in histological sections of one lesion, but a species identification could not be made. The possible cause of the lesions is discussed.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. 
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Jacobs, J.C.

Newsholme, S.J.

Verster, Anna J.M.

The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. 
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Circumscribed, ulcerative skin lesions, usually situated caudal to the scapula, affected cattle in the Republic of Venda during the summer of 1981-82. The occurrence of the lesions was associated with heavy infestations of the hornfly, Haematobia meridiana. Microscopically the lesions were characterized by intense eosinophilic dermatitis. Microfilariae were seen in histological sections of one lesion, but a species identification could not be made. The possible cause of the lesions is discussed

UPSpace at the University of Pretoria

Onderstepoorr J. vet. Res. , 50, H-75 (1983) BOVINE SKIN LESIONS OF POSSIBLE FILARIAL ORIGIN ASSOCIATED WITH HEAVY HORNFLY INFESTATIONS (HAEMATOBIA MERIDIANA) S. J. NEWSHOLME(l), ANNA J. M. VERSTER<2> and J. C. JACOBS<3> ABSTRACT NEWSHOLME, S. J., VERSTER, ANNA J. M. & JACOBS, J. C., 1983. Bovine skin lesions of possible filarial origin associated with heavy homfly infestations (Haematobia meridiana). Onderstepoort Journal of Veterinary Research, 50, 73--75 (1983). Circumscribed, ulcerative skin lesions, usually situated caudal to the scapula, affected cattle in the Republic of Venda during the summer of 1981-82. The occurrence of the lesions was associated with heavy infestations of the homfly, Haematobia meridiana. Microscopically the lesions were characterized by intense eosinophilic dermatitis. Microfilariae were seen in histological sections of one lesion, but a species identification could not be made. The possil:ile cause of the lesions is discussed. INTRODUCTION During the summer of 1981-82, circumscribed skin lesions affected adult cattle grazing throughout the region north of the Soutpansberg, in the Republic of Venda. This area is predominantly Mopani veld (Acocks, 1975). The lesions were first noticed in Octo-ber 1981 and their incidence increased throughout the summer. In May 1982 an estimated 5-10% of these cattle were affected. Veterinary staff in the area had not previously observed such lestons. The occurrence of these lesions was associated with the appearance of unusually large populations of biting flies which at-tended the cattle throughout the summer. This report deals with the pathology of the lesions and their possible origin. MATERIALS AND METHODS In May 1982, a biopsy specimen collected from a skin lesion on the lateral thorax of a heifer was fixed in 10% buffered formalin. Paraffin sections of this material were prepared and stained with haematoxylin and eosin (HE) according to standard procedures for light microscopy. In June 1982 skin lesions were removed surgically from the lateral thorax of 2 cows. Part of this material was fixed in formalin for li~ht microscopy, part was digested in pepsinlhydrochlonc acid and the remainder was placed in a Baermann apparatus to recover any nematodes that might be present. One millilitre of venous blood, collected into 9 me of formalin (2%) from each of 10 cattle showing lesions, was examined for microfllariae. Flies were collected from the backs of affected cattle for identification. RESULTS Clinical and macroscopic observations The lesions were well-circumscribed, slightly raised, hairless areas of thickened skin, and varied in diameter from 5-30 em. Smaller lesions were circular to oval and the largest ones were elongated dorsoventrally (Fig. 1 & 2). Lesions were frequently ulcerated, had multiple sur-face fissures (Fi~. 2), and were occasionally covered in dried blood (Ftg. 1). Small beads of fresh blood appeared if the lesions were squeezed. Most of the lesions were situated on the lateral thorax immediately caudal to the scapula (Fig. 1). Occasional lesions also occurred at various sites over the thorax and abdomen (Fig. 3). Bilateral occurrence of the lesions was a striking feature in most cases. Microscopical findings Severe eosinophilic dermatitis, which was character-ized by intense eosinophil infiltration throughout the dermis, was a consistent feature in all formalin-fixed O> Section of Pathology, Veterinary Research Institute, Ondrstepoort OliO <l> Section of Helminthology , Veterinary Research Institute, Onderste-poort OliO <J> Chief Veterinarian, Private Bag X2224, Sibasa, Republic of Venda Received 5 November 1982- Editor 73 material (Fig. 4 & 5). Eosinophils were particularly abundant around small arterioles and venules in the deep dermis (Fig. 6 & 7), where they were accompanied by a few plasma cells. Epidermal loss with associated dermal fibro{llasia was extensive (Fig. 8). Small segments of the remaming epidermis displayed moderate to severe acan-thosis and parakeratosis (Fig. 4). FIG. I Lesions caudal to the scapula FIG. 2 Ulcerated lesion on lateral thorax BOVINE SKIN LESIONS OF POSSIBLE FILARIAL ORIGIN ASSOCIATED WITH HORNFL Y INFESTATIONS FIG. 3 Lesions scattered over lateral thorax and abdomen Microfilariae occurred singly or in small groups within the rapillary dermis in several different areas of the materia from the lesion first collected (Fig. 9). They measured approximately 3 JLm in width, but their length could not be determined. Microfilariae were not seen in the lesions from the other cases. No adult parasites could be found. Parasitology No nematodes were recovered from the biopsy material, nor were microfilariae present in the blood examined. The flies collected were all identified according to Zumpt (1973) as specimens of the homfly, Haematobia meridiana. FIG. 4 Dermal inflammatory infiltrate, acanthosis and parakeratosis: HE x 100 FIG. 5 Abundant eosinophils in dermis: HE x 400 FIG. 6 Perivascular eosinophils in deep dermis: HE x 100 FIG. 7 Eosinophils around an arteriole in the deep dermis: HE X 100 74 S. J. NEWSHOLME, ANNA J. M. VERSTER & J. C. JACOBS FIG. 8 Epidermal loss and necrotic debris overlying affected dermis: HE X 30 FIG. 9 A microfilaria (arrowed) in the dermis: HE x 600 DISCUSSION The cause of these lesions could not be determined, nor was it possible to identify the species of the microfi-lariae that were seen in tissue sections of the lesion from the heifer. The abundance of eosinophils, however, did suggest a parasitic aetiology. The cattle were situated in an area where bovine parafilariosis is known to occur (Carmichael & Koster, 1978). However, lesions caused by Parafilaria bovicola are situated predominantly in the subcutis with minimal dermal and no epidermal involve-ment (Pienaar & Van den Heever, 1964). Furthermore, micro filariae of P. bovicola are markedly broader than the microfilariae in our material which, according to Levine (1968), are comparable in breadth to those of Onchocerca spp. and Stephanofilaria spp. in cattle. To our knowledge, Onchocerca spp. do not cause cutaneous lesions resembling these in cattle. Skin lesions asso-ciated with Stephanofilaria spp., which resembled the lesions in the Venda cattle both morphologically and in their bodily distribution, have been described in cattle in Indonesia in the condition known as "cascado" (Bub-berman & Kraneveld, 1933), in cattle in Australia (John-son, Parker, Norton, Jaques & Grimshaw, 1981) and in Nigeria (Oduye, 1971). Bovine stephanofilariasis has not been reported in South Africa, but ulcerative skin. lesions situated caudal to the scapula and associated with microfilariae have been described in black rhinoceros (Diceros bicornis) in Hluhluwe and Mkuzi, Zululand (Schulz & Kluge, 1960). Nematodes recovered from similar lesions in black rhinoceros from Hluhluwe were identified subsequently as Stephanofilaria dinniki Round, 1964 (Verster & Hitchins, unpublished record, 1969). Failure to find adult parasites in these lesions and the demonstration of microfilariae in only one of them do not exclude a filarial aetiology. Although Stephano-filaria has been associated with bovine skin lesions in Australia, workers often failed to find filariae in such lesions (R. W. Sutherst, CSIRO, Long Pocket Laborato-ries, lndooroopilly, Queensland, Australia, personal communication, 1981). A direct effect of the heavy fly infestations upon the development of the lesions cannot be discounted, but in our view severe eosinophilic der-matitis is not a feature of fly bites alone. Should such lesions occur in future, further investiga-tion is warranted to establish their aetiology. 75 Ai<NOWLEDGEMENTS We wish to thank Dr E. M. Nevill for identifying the flies, the staff of the Section of Pathology for preparing and staining the histological sections and the staff of the Section of Photography for preparing the photographs. REFERENCES ACOCKS, J. P. H., 1975. Veld types of South Africa. 2nd ed. Memoirs of the Botanical Survey of South Africa, No. 40, 128 pp. BUBBERMAN, C. & KRANEVELD, F. C., 1933. Overeen dermati-tis squamosa et crustosa circumscripta bij het rund in Nederlandsch-Indie, genaard cascado. I. Onderzoekingen over aard en wezen der cascado. Nederlandsch-lndische Bladen voor Diergeneeskunde, 45, 239-278. CARMICHAEL, I. H. & KOSTER, SUSAN, 1978. Bovine parafila-riosis in southern Africa: a preliminary report. Onderstepoort Jour-nal of Veterinary Research. 45, 213-214. JOHNSON, S. J., PARKER, R. J., NORTON, J. H., JAQUES, P. A. & GRIMSHAW, A. A., 1981. Stephanofilariasis in cattle. Austra-lian Veterinary Journal, 57, 411--413. LEVINE, N. D., 1968. Nematode parasites of domestic animals and of man. Minneapolis: Burgess. ODUYE, 0 . 0. , 1971. Stephanofilaria! dermatitis of cattle in Nigeria. Journal of Comparative Pathology, 81, 581-583. PIENAAR, J. G. & VAN DEN HEEVER, L. W. , 1964. Parafilaria bovicola Tubangui, 1934, in cattle in the Republic of South Africa. Journal of the South African Veterinary Medical Association, 35, 181-184. ROUND, M. C., 1964. A new species of Stephanofilaria in skin lesions from the black rhinoceros (Diceros bicornis L.) in Kenya. Journal of Helminthology, 38, 87-96. SCHULZ, K. C. A. & KLUGE, E. B .• 1960. Dermatitis in the black rhinoceros (Diceros bicornis) due to skin filariasis . Journal of the South African Veterinary Medical Association, 31 , 265-269. ZUMPT, F., 1973. The stomoxyine biting flies of the world. Stuttgart: Gustaf Fisher. 

Bovine skin lesions of possible filarial origin associated with heavy hornfly infestations (Haematobia meridiana)

https://repository.up.ac.za/bitstream/2263/50525/1/11newsholme1983.pdf

Bovine skin lesions of possible filarial origin associated with heavy hornfly infestations (Haematobia meridiana)

Abstract

Similar works

Full text

Available Versions

UPSpace at the University of Pretoria