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Coccidia in rabbits (Oryctolagus cuniculus) in Saudi Arabia
Parasitology, Vo/. 17, No.
InternarionalJoournalfor Printed in Greor Britain.
4, pp. 941-944.1987.
0020-7519/87 $3.00 + 0.00 Pergomon Journals Ltd. 8 1987 Au.walian Society for Parasilology
COCCIDIA IN RABBITS (OR YCTOLAGUS IN SAUDI ARABIA
CUMCULUS)
A. A. KASIMand Y. R. AL-SHAWA Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 1145 1, Saudi Arabia (Received 9 May 1986) Abstract-KAsm, A. A. and AL-SHAWAY. R. 1987. Coccidia in rabbits (Oryctolagm cuniculus) in Saudi Arabia. InternationalJournalfor Parasitology17: 941-944. Seven species of coccidia were identified and described for the first timeinSaudiArabiain263faecalsamulesofdomesticrabbits lOrvctolanuscuniculus~. A totalof73%ofthespecimenswerepositive,mostofthemdontained lOOO-10,000bofystspergram.Mixeh infections with three Eimeria species were common. Eimeria perforans and E. media occurred most frequently, E. magna, E. coecicola and E. irresidua were less common and E. flavescens and E. intestinalis were relatively rare.
INDEX KEY WORDS: Eimeria; rabbit; Oryctoluguscuniculus, incidence of infection; description; Saudi Arabia.
INTRODUCTION
nab; E. iwesidua; E. magna; E. media; E. perforans. The morphological characteristics of the various spor-
Eimeria
infection is common in cattle, sheep and camels in Saudi Arabia (Kasim & Al-Shawa, 1985a, b, Kasim, Hussein & Al-Shawa, 1985). To our knowledge there is no published report of Eimeria infection in rabbits in Saudi Arabia. The present study was undertaken to determine the prevalence and intensity of coccidia in domestic rabbits and to describe the sporulated oocysts of the seven species of Eimeria, which had not been previously identified in the Kingdom of Saudi Arabia. MATERIALS
ulated oocysts are shown in Figs l-9 and Table 1. A total of 73% of the animals were found positive for Eimeria species (Table 2). Mixed infections with three species occurred most frequently, and 5 1.O% of the specimens contained three to five species. The highest prevalence of infection was reported in the central region (83.3%) and the lowest in the western region (54.4%). The prevalence of the seven species of Eimeria are recorded in Table 3. Eimeria pegorans and E. media occurred most frequently and were generally the most predominant species; E. magna, E. coecicola and E. iwesidua were less common and E. jlavescens and E. intestinalis were relatively rare. The level of infection with coccidial oocysts is shown in Table 4. Most of the specimens contained lOOO-10,000 oocysts per gram. Rabbits in the central region not only had the highest prevalence, but also the highest number of oocysts per gram.
AND METHODS
Two hundred and sixty three adult domestic rabbits from farms and rabbit markets in the central, eastern and western regions of Saudi Arabia were collected during the year 1984-1985. At necropsy caecal and colon contents were removed separately and subjected to examination using a McMaster egg-counting technique (Parfitt, 19.58). Samples which were found to be negative were re-examined using the sugar flotation concentration technique. A proportion of the screened faecal suspension was incubated in a shallow layer of 2.5% (w/v) aqueous potassium dichromate solution and kept at 25-28’C and examined periodically to determine sporulation times. At least 50 sporulated oocysts from each species were measured with a 100X achromatic oil immersion objective with 10X eyepieces. AU measurements arein micrometers, and the means are in parentheses after the ranges. The coccidial species were identified using morphological and morphometric criteria (Levine & Ivens, 1972; Pelltrdy, 1974; Catchpole &Norton, 1979).
DISCUSSION Coccidial
RESULTS The
study disclosed the presence of seven species of Eimeria from the faecal samples of 363 domestic rabbits collected from three regions of Saudi Arabia. These are Eimeria coecicola; E. flavescens; E. intesti-
infection occurs widely in a high proportion of domestic rabbits throughout the three regions in Saudi Arabia, but with varying degrees of prevalence in different countries (Catchpole & Norton, 1979; Jin-Shu, 1981; Peeters, Geeroms, Froyman & Halen, 1981). Seven species of Eimeria were recognized and described for the first time in Saudi Arabian rabbits. Several authors have found that Eimeria media, E. magna, E. flavescens and E. intestinalis are the most pathogenic (Rutherford, 1943; Pellerdy, 1974; Catchpole & Norton, 1979; Norton, Catchpole &
941
A.
A.
KASIM
and Y. R. AL-SHAWA
FIGS. l-9. Photomicrographs of sporulatedoocysts of seven species of Eimeria in rabbits. 1,2. Eimeria coecicala. 1. Shows a sporocyst with a single refractle globule, 2. Shows the oocyst residuum clearly; 3. Ej7avescen.s; 4. E. intestinalis; 5. E. irresidua; 6. E. magna; 7,8. E. media. 7. Shows the oocyst residuum clearly, 8. Shows an oocyst apparently lacking a
micropyle; 9. E. p~~orans. Joyner, 1979). The data reported in Table 3 indicate that these species are common in Saudi Arabia. Our
observation on the affected rabbits displayed signs of inflammatory lesions in the small intestine and caecum. The intestinal contents were pasty and diarrhoeal and contained mucus. The rabbits were
Iistkss
and showed
a reduction
of weight.
E~~e~~
infection is most prevalent in the central region of the Kingdom. This can be explained by the fact that intensive rearing methods and poor management are commoner in this region. Our descriptions of the sporulated oocysts of
,,,.
ellipsoid
ovoid
ovoidal to ellipsoid
ellipsoid
E. irresidua
E. magna
E. media
E. peeorans
.”
pear shaped
E. intestinalis
,,,^,*, ,., ,“.
ovoid
E. jiavescens
1.18-1.83 (1.53)
1.42-1.76 (1.61)
1.38-1.54 (1.47)
1.44-1.96 (1.56)
1.47-1.59 (1.52)
,;x _.. -,.- ._,“I..““._ _..- -*“, _“.~ -..
11.3-19.5 (20.9 X 13.7)
X
14.1-26.8
15.0-22.2 (30.0 X 18.7)
X
25.5-34.3
2 1.O-26.5 (35.4 X 24.2)
X
28.7-40.0
2 1.O-26.0 (37.1 X 23.8)
X
33.0-43.0
16.8-22.0 (29.2 X 19.3)
X
24.7-34.1
17.0-25.0 (32.0 X 21.2)
X
26.8-37.5
15.5-22.1 (33.4 x 19.3) 1.42-1.98 (1.51)
1.43-2.15 (1.73)
28.4-40.0
cylindrical to elongate ellipsoid
E. coecicola X
Shape index
Size
^.
Oocyst
Shape
Eimeria species
-
+
+
+
+
+
+
Micropyle
(3.9)
3.1-5.0
(6.4)
4.4-7.2
9.0-14.2 (11.8)
-
(5.9)
4.3-7.0
-
4.1-6.6 (9.7 x 5.1)
X
8.0-l 1.4
5.Or8.5 (12.9 X 6.6)
9.3-15.6
7.0-11.5 (17.2 X 9.0)
X
11.8-20.0
7.8-10.9 (18.5 X 9.3)
X
15.7-21.9
6.3-8.1 (13.1 X 7.3)
X
10.0-16.5
6.8-10.0 (15.0 x 8.4)
X
12.5-17.2
6.0x8.9 (15.1 X 7.2)
1.67-2.25 (1.91)
1.83-2.33 (1.96)
1.83-2.33 (1.92)
1.64-2.20 (1.99)
1.54-2.04 (1.80)
1.72-2.00 (1.79)
1.75-2.43 (2.10)
11.8-19.0
3.6-6.1 (5.1)
Shape index
Size
Residuum
_.__._^_.___“__-..._ ._,~._ _~.__._I .__ _ _I. __,. _I.. __.. ___ ___ ___ -I
light pink
yellowish brown
yellowish brown
greenish brown
light brown
yellowish green
Wall colour
Sporocyst
TABLE ~-MORPHOLOGICAL AND PROPORTIONALMEASUREMENTSOF SEVEN SPECIESOF EimeriaF~oM SAUDI ARABIA
“.
24
36
48
38
56
Sporulation time (h)
944
A. A. KASIM and Y. R. AL-SHAWA
TABLE ~-THE
NUMBER OF Eimeria SPEC~XS IN RABBITS(%) IN SAUDI ARABIA
Region and number No. of Eimeria species
of rabbits
INDIVIDUAL
examined
Central 168
Eastern 105
Western 90
All of country 363
0 1 2 3 4 5 6 7
16.7 6.5 11.9 21.4 25.0 14.9 3.0 0.6
27.6 8.6 11.4 26.7 16.2 6.7 1.9 1.0
45.6 5.6 14.4 18.9 11.1 3.3 1.1 0.0
27.0 6.9 12.4 22.3 19.0 9.7 2.2 0.6
Total Positive
83.3
72.5
54.4
73.0
TABLE ~-PREVALENCE OF Eimeria SPECIES SAUDI ARABIAN RABBITS
(%)
IN
Region Eimeria species E. E. E. E. E. E. E.
coecicola fi’avescens intestinalis irresidua magna media perforans
Central
Eastern
42.3 25.0 4.2 30.4 49.4 64.9 75.0
32.4 4.8 1.9 37.1 46.7 42.9 61.9
Western 28.9 16.7 1.1 21.1 20.0 33.3 36.7
All of country 36.1 17.1 2.8 30.0 41.3 50.7 61.7
TABLE ~-THE PERCENTAGE DISTRIBUTION OF THE NUMBERS OF COCCIDIALOOCYSTSPER GRAMIN FAECALSAMPLESFROM INFECTEDRABBITS Region Oocysts/g of faeces
Central
Eastern
Western
All of country
10.7 19.3 29.3 27.1 13.6
21.1 17.1 30.3 23.7 7.9
22.4 24.5 28.6 18.4 6.1
15.8 19.6 29.5 24.5 10.6
Eimeria species from Saudi Arabian rabbits vary slightly in size and other minor characteristics from previous descriptions (Francalancia & I&nfredini, 1967; Cheissin, 1968; PellQdy, 1974; Norton et al., 1979).
REFERENCES CATCHPOLE J. & NORTON C. C. 1979. The species of Eimeria in rabbits for meat production in Britain. Parasitology 79: 249-257. CHEISSIN E. M. 1968. On the distinctness of the species Eimeria neoleporis Carvalho, 1942 from the cottontail rabbit Sylvilagus floridanus mearnsii and Eimeria coecicola Cheissin, 1947 from the tame rabbit Oryctolagus cuniculus. Acta Protozoologica 6: 5-12. FRANCALANCIA G. & MANFREDINI L. 1967. Diagnosis of species of the rabbit coccidiosis. Veterinaria Ztaliana 18: 304-310. JIN-SHU J. 1981. Survey of rabbit coccidiosis at a laboratory animal unit in the Beijing district of China. Chinese Journal of Veterinary Medicine 7: 6-7. KASIM A. A. & AL-SHAWA Y. R. 1985a. Prevalence of Eimeria in faeces of cattle in Saudi Arabia. Veterinary Parasitology 17: 95-99. KASIM A. A. & AL-SHAWA Y. R. 1985b. Coccidiain sheep (Ovis aries) in Saudi Arabia. Journal of the College of Science, King Saud University 16: 193-283. KASIM A. A., HUSSEIN H. S. & AL-SHAWA Y. R. 1985. Coccidia in camels (Camelus dromedarius) in Saudi Arabia. Journal ofProtozoology 32: 202-203. LEVINE N. D. & IVENS V. 1972. Coccidia of the Leporidae. Journal ofProtozoology 19: 572-581. NORTON C.C., CATCHPOLE J. & JOYNER L.P. 1979. Redescriptions of Eimeria irresidua Kessel& JANKIEWICZ, 1931 AND Eflavescens Marotel & Guilhon, 1941 from the domestic rabbit. Parasitology 79: 231-248. PARFITT J. W. 1958. A technique for the enumeration of helminth eggs and protozoan cysts in faeces from farm animals in Britain. Laboratory Practice I: 353-355. PEETERS J. E., GEEROMS R., FROYMANR. & HALEN P. 1981. Coccidiosis in rabbits: a field study. Research in Veterinary Science 30: 328-334. PELLBRDY L. P. 1974. Coccidia and Coccidiosis, 2nd edn. Paul Parey, Berlin and Hamburg. RUTHERFORD R. L. 1943. The life-cycle of four intestinal coccidia of the domestic rabbit. Journal of Parasitology 29: 10-32.
InternarionalJoournalfor Printed in Greor Britain.
4, pp. 941-944.1987.
0020-7519/87 $3.00 + 0.00 Pergomon Journals Ltd. 8 1987 Au.walian Society for Parasilology
COCCIDIA IN RABBITS (OR YCTOLAGUS IN SAUDI ARABIA
CUMCULUS)
A. A. KASIMand Y. R. AL-SHAWA Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 1145 1, Saudi Arabia (Received 9 May 1986) Abstract-KAsm, A. A. and AL-SHAWAY. R. 1987. Coccidia in rabbits (Oryctolagm cuniculus) in Saudi Arabia. InternationalJournalfor Parasitology17: 941-944. Seven species of coccidia were identified and described for the first timeinSaudiArabiain263faecalsamulesofdomesticrabbits lOrvctolanuscuniculus~. A totalof73%ofthespecimenswerepositive,mostofthemdontained lOOO-10,000bofystspergram.Mixeh infections with three Eimeria species were common. Eimeria perforans and E. media occurred most frequently, E. magna, E. coecicola and E. irresidua were less common and E. flavescens and E. intestinalis were relatively rare.
INDEX KEY WORDS: Eimeria; rabbit; Oryctoluguscuniculus, incidence of infection; description; Saudi Arabia.
INTRODUCTION
nab; E. iwesidua; E. magna; E. media; E. perforans. The morphological characteristics of the various spor-
Eimeria
infection is common in cattle, sheep and camels in Saudi Arabia (Kasim & Al-Shawa, 1985a, b, Kasim, Hussein & Al-Shawa, 1985). To our knowledge there is no published report of Eimeria infection in rabbits in Saudi Arabia. The present study was undertaken to determine the prevalence and intensity of coccidia in domestic rabbits and to describe the sporulated oocysts of the seven species of Eimeria, which had not been previously identified in the Kingdom of Saudi Arabia. MATERIALS
ulated oocysts are shown in Figs l-9 and Table 1. A total of 73% of the animals were found positive for Eimeria species (Table 2). Mixed infections with three species occurred most frequently, and 5 1.O% of the specimens contained three to five species. The highest prevalence of infection was reported in the central region (83.3%) and the lowest in the western region (54.4%). The prevalence of the seven species of Eimeria are recorded in Table 3. Eimeria pegorans and E. media occurred most frequently and were generally the most predominant species; E. magna, E. coecicola and E. iwesidua were less common and E. jlavescens and E. intestinalis were relatively rare. The level of infection with coccidial oocysts is shown in Table 4. Most of the specimens contained lOOO-10,000 oocysts per gram. Rabbits in the central region not only had the highest prevalence, but also the highest number of oocysts per gram.
AND METHODS
Two hundred and sixty three adult domestic rabbits from farms and rabbit markets in the central, eastern and western regions of Saudi Arabia were collected during the year 1984-1985. At necropsy caecal and colon contents were removed separately and subjected to examination using a McMaster egg-counting technique (Parfitt, 19.58). Samples which were found to be negative were re-examined using the sugar flotation concentration technique. A proportion of the screened faecal suspension was incubated in a shallow layer of 2.5% (w/v) aqueous potassium dichromate solution and kept at 25-28’C and examined periodically to determine sporulation times. At least 50 sporulated oocysts from each species were measured with a 100X achromatic oil immersion objective with 10X eyepieces. AU measurements arein micrometers, and the means are in parentheses after the ranges. The coccidial species were identified using morphological and morphometric criteria (Levine & Ivens, 1972; Pelltrdy, 1974; Catchpole &Norton, 1979).
DISCUSSION Coccidial
RESULTS The
study disclosed the presence of seven species of Eimeria from the faecal samples of 363 domestic rabbits collected from three regions of Saudi Arabia. These are Eimeria coecicola; E. flavescens; E. intesti-
infection occurs widely in a high proportion of domestic rabbits throughout the three regions in Saudi Arabia, but with varying degrees of prevalence in different countries (Catchpole & Norton, 1979; Jin-Shu, 1981; Peeters, Geeroms, Froyman & Halen, 1981). Seven species of Eimeria were recognized and described for the first time in Saudi Arabian rabbits. Several authors have found that Eimeria media, E. magna, E. flavescens and E. intestinalis are the most pathogenic (Rutherford, 1943; Pellerdy, 1974; Catchpole & Norton, 1979; Norton, Catchpole &
941
A.
A.
KASIM
and Y. R. AL-SHAWA
FIGS. l-9. Photomicrographs of sporulatedoocysts of seven species of Eimeria in rabbits. 1,2. Eimeria coecicala. 1. Shows a sporocyst with a single refractle globule, 2. Shows the oocyst residuum clearly; 3. Ej7avescen.s; 4. E. intestinalis; 5. E. irresidua; 6. E. magna; 7,8. E. media. 7. Shows the oocyst residuum clearly, 8. Shows an oocyst apparently lacking a
micropyle; 9. E. p~~orans. Joyner, 1979). The data reported in Table 3 indicate that these species are common in Saudi Arabia. Our
observation on the affected rabbits displayed signs of inflammatory lesions in the small intestine and caecum. The intestinal contents were pasty and diarrhoeal and contained mucus. The rabbits were
Iistkss
and showed
a reduction
of weight.
E~~e~~
infection is most prevalent in the central region of the Kingdom. This can be explained by the fact that intensive rearing methods and poor management are commoner in this region. Our descriptions of the sporulated oocysts of
,,,.
ellipsoid
ovoid
ovoidal to ellipsoid
ellipsoid
E. irresidua
E. magna
E. media
E. peeorans
.”
pear shaped
E. intestinalis
,,,^,*, ,., ,“.
ovoid
E. jiavescens
1.18-1.83 (1.53)
1.42-1.76 (1.61)
1.38-1.54 (1.47)
1.44-1.96 (1.56)
1.47-1.59 (1.52)
,;x _.. -,.- ._,“I..““._ _..- -*“, _“.~ -..
11.3-19.5 (20.9 X 13.7)
X
14.1-26.8
15.0-22.2 (30.0 X 18.7)
X
25.5-34.3
2 1.O-26.5 (35.4 X 24.2)
X
28.7-40.0
2 1.O-26.0 (37.1 X 23.8)
X
33.0-43.0
16.8-22.0 (29.2 X 19.3)
X
24.7-34.1
17.0-25.0 (32.0 X 21.2)
X
26.8-37.5
15.5-22.1 (33.4 x 19.3) 1.42-1.98 (1.51)
1.43-2.15 (1.73)
28.4-40.0
cylindrical to elongate ellipsoid
E. coecicola X
Shape index
Size
^.
Oocyst
Shape
Eimeria species
-
+
+
+
+
+
+
Micropyle
(3.9)
3.1-5.0
(6.4)
4.4-7.2
9.0-14.2 (11.8)
-
(5.9)
4.3-7.0
-
4.1-6.6 (9.7 x 5.1)
X
8.0-l 1.4
5.Or8.5 (12.9 X 6.6)
9.3-15.6
7.0-11.5 (17.2 X 9.0)
X
11.8-20.0
7.8-10.9 (18.5 X 9.3)
X
15.7-21.9
6.3-8.1 (13.1 X 7.3)
X
10.0-16.5
6.8-10.0 (15.0 x 8.4)
X
12.5-17.2
6.0x8.9 (15.1 X 7.2)
1.67-2.25 (1.91)
1.83-2.33 (1.96)
1.83-2.33 (1.92)
1.64-2.20 (1.99)
1.54-2.04 (1.80)
1.72-2.00 (1.79)
1.75-2.43 (2.10)
11.8-19.0
3.6-6.1 (5.1)
Shape index
Size
Residuum
_.__._^_.___“__-..._ ._,~._ _~.__._I .__ _ _I. __,. _I.. __.. ___ ___ ___ -I
light pink
yellowish brown
yellowish brown
greenish brown
light brown
yellowish green
Wall colour
Sporocyst
TABLE ~-MORPHOLOGICAL AND PROPORTIONALMEASUREMENTSOF SEVEN SPECIESOF EimeriaF~oM SAUDI ARABIA
“.
24
36
48
38
56
Sporulation time (h)
944
A. A. KASIM and Y. R. AL-SHAWA
TABLE ~-THE
NUMBER OF Eimeria SPEC~XS IN RABBITS(%) IN SAUDI ARABIA
Region and number No. of Eimeria species
of rabbits
INDIVIDUAL
examined
Central 168
Eastern 105
Western 90
All of country 363
0 1 2 3 4 5 6 7
16.7 6.5 11.9 21.4 25.0 14.9 3.0 0.6
27.6 8.6 11.4 26.7 16.2 6.7 1.9 1.0
45.6 5.6 14.4 18.9 11.1 3.3 1.1 0.0
27.0 6.9 12.4 22.3 19.0 9.7 2.2 0.6
Total Positive
83.3
72.5
54.4
73.0
TABLE ~-PREVALENCE OF Eimeria SPECIES SAUDI ARABIAN RABBITS
(%)
IN
Region Eimeria species E. E. E. E. E. E. E.
coecicola fi’avescens intestinalis irresidua magna media perforans
Central
Eastern
42.3 25.0 4.2 30.4 49.4 64.9 75.0
32.4 4.8 1.9 37.1 46.7 42.9 61.9
Western 28.9 16.7 1.1 21.1 20.0 33.3 36.7
All of country 36.1 17.1 2.8 30.0 41.3 50.7 61.7
TABLE ~-THE PERCENTAGE DISTRIBUTION OF THE NUMBERS OF COCCIDIALOOCYSTSPER GRAMIN FAECALSAMPLESFROM INFECTEDRABBITS Region Oocysts/g of faeces
Central
Eastern
Western
All of country
10.7 19.3 29.3 27.1 13.6
21.1 17.1 30.3 23.7 7.9
22.4 24.5 28.6 18.4 6.1
15.8 19.6 29.5 24.5 10.6
Eimeria species from Saudi Arabian rabbits vary slightly in size and other minor characteristics from previous descriptions (Francalancia & I&nfredini, 1967; Cheissin, 1968; PellQdy, 1974; Norton et al., 1979).
REFERENCES CATCHPOLE J. & NORTON C. C. 1979. The species of Eimeria in rabbits for meat production in Britain. Parasitology 79: 249-257. CHEISSIN E. M. 1968. On the distinctness of the species Eimeria neoleporis Carvalho, 1942 from the cottontail rabbit Sylvilagus floridanus mearnsii and Eimeria coecicola Cheissin, 1947 from the tame rabbit Oryctolagus cuniculus. Acta Protozoologica 6: 5-12. FRANCALANCIA G. & MANFREDINI L. 1967. Diagnosis of species of the rabbit coccidiosis. Veterinaria Ztaliana 18: 304-310. JIN-SHU J. 1981. Survey of rabbit coccidiosis at a laboratory animal unit in the Beijing district of China. Chinese Journal of Veterinary Medicine 7: 6-7. KASIM A. A. & AL-SHAWA Y. R. 1985a. Prevalence of Eimeria in faeces of cattle in Saudi Arabia. Veterinary Parasitology 17: 95-99. KASIM A. A. & AL-SHAWA Y. R. 1985b. Coccidiain sheep (Ovis aries) in Saudi Arabia. Journal of the College of Science, King Saud University 16: 193-283. KASIM A. A., HUSSEIN H. S. & AL-SHAWA Y. R. 1985. Coccidia in camels (Camelus dromedarius) in Saudi Arabia. Journal ofProtozoology 32: 202-203. LEVINE N. D. & IVENS V. 1972. Coccidia of the Leporidae. Journal ofProtozoology 19: 572-581. NORTON C.C., CATCHPOLE J. & JOYNER L.P. 1979. Redescriptions of Eimeria irresidua Kessel& JANKIEWICZ, 1931 AND Eflavescens Marotel & Guilhon, 1941 from the domestic rabbit. Parasitology 79: 231-248. PARFITT J. W. 1958. A technique for the enumeration of helminth eggs and protozoan cysts in faeces from farm animals in Britain. Laboratory Practice I: 353-355. PEETERS J. E., GEEROMS R., FROYMANR. & HALEN P. 1981. Coccidiosis in rabbits: a field study. Research in Veterinary Science 30: 328-334. PELLBRDY L. P. 1974. Coccidia and Coccidiosis, 2nd edn. Paul Parey, Berlin and Hamburg. RUTHERFORD R. L. 1943. The life-cycle of four intestinal coccidia of the domestic rabbit. Journal of Parasitology 29: 10-32.